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Susitna‐Watana Hydroelectric Project Document
ARLIS Uniform Cover Page
Title:
Salmon escapement study, Study plan Section 9.7, Study Completion
Report SuWa 289
Author(s) – Personal:
Author(s) – Corporate:
LGL Alaska Research Associates, Inc.
Alaska Department of Fish and Game, Division of Sport Fish
AEA‐identified category, if specified:
November 2015; Study Completion and 2014/2015 Implementation Reports
AEA‐identified series, if specified:
Series (ARLIS‐assigned report number):
Susitna-Watana Hydroelectric Project document number 289
Existing numbers on document:
Published by:
[Anchorage : Alaska Energy Authority, 2015]
Date published:
October 2015
Published for:
Alaska Energy Authority
Date or date range of report:
Volume and/or Part numbers:
Study plan Section 9.7
Final or Draft status, as indicated:
Document type:
Pagination:
330 pages in various pagings
Related work(s):
Salmon escapement study, Study plan Section 9.7, errata to
Study Completion Report (November 9, 2015)
Pages added/changed by ARLIS:
Notes:
This report is dated October 2015, but it was filed with the Federal Energy Regulatory Commission
(FERC) on November 9, 2015; thus the November date in reference to Study Plan appears in the
title of this errata document.
All reports in the Susitna‐Watana Hydroelectric Project Document series include an ARLIS‐
produced cover page and an ARLIS‐assigned number for uniformity and citability. All reports
are posted online at http://www.arlis.org/resources/susitna‐watana/
Susitna-Watana Hydroelectric Project
(FERC No. 14241)
Salmon Escapement Study
Study Plan Section 9.7
Study Completion Report
Prepared for
Alaska Energy Authority
Prepared by
LGL Alaska Research Associates, Inc. &
Alaska Department of Fish and Game, Division of Sport Fish
October 2015
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page i October 2015
TABLE OF CONTENTS
1. Introduction ....................................................................................................................... 1
2. Study Objectives................................................................................................................ 1
3. Study Area ......................................................................................................................... 2
4. Methods .............................................................................................................................. 2
4.1. Objective 1: Capture, radio-tag, and track adults of five species of Pacific
salmon in the Middle and Upper Susitna River in proportion to their
abundance. Capture and tag Chinook, Coho, and Pink salmon in the Lower
Susitna and Yentna rivers. .................................................................................3
4.1.1. Fish Capture .....................................................................................3
4.1.2. Radio-tagging ...................................................................................5
4.1.3. Tagging Goals ..................................................................................6
4.1.4. Numbers and Size of Marked and Unmarked Fish at Selected
Locations ..........................................................................................7
4.1.5. Examining Handling-Induced Changes in Behavior .....................10
4.1.6. Variances ........................................................................................11
4.2. Objective 2: Determine the migration behavior and spawning locations of
radio-tagged fish in the Lower, Middle, and Upper Susitna River ..................13
4.2.1. Fixed-station Monitoring ...............................................................13
4.2.2. Aerial Telemetry Surveys ..............................................................15
4.2.3. Telemetry Data Analysis ................................................................17
4.2.4. Variances ........................................................................................20
4.3. Objective 3: Characterize adult salmon migration behavior and timing within
and above Devils Canyon ................................................................................20
4.3.1. Fixed-station Monitoring ...............................................................20
4.3.2. Aerial Telemetry Surveys ..............................................................21
4.3.3. Aerial Spawner Surveys .................................................................21
4.3.4. Using Sonar to Enumerate Salmon at the Proposed Dam Site ......22
4.3.5. Variances ........................................................................................22
4.4. Objective 4: Use available technology to document salmon spawning
locations in turbid water...................................................................................23
4.4.1. Sonar Equipment and Methods ......................................................23
4.4.2. Sonar Data Analysis and Reporting ...............................................24
4.4.3. Variances ........................................................................................24
4.5. Objective 5: Compare historical and current data on run timing, distribution,
relative abundance, and specific locations of spawning and holding salmon ..25
4.5.1. Variances ........................................................................................25
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page ii October 2015
4.6. Objective 6: Generate counts of adult Chinook Salmon spawning in the
Susitna River and its tributaries .......................................................................25
4.6.1. Variances ........................................................................................26
4.7. Objective 7: Collect tissue samples to support the Fish Genetics Study .........27
4.7.1. Variances ........................................................................................27
4.8. Objective 8: Estimate the system-wide Chinook Salmon escapement and the
Coho Salmon escapement to the Susitna River above the Yentna River, and
the distribution of those fish among tributaries of the Susitna River ..............27
4.8.1. Variances ........................................................................................29
5. Results .............................................................................................................................. 30
5.1. Objective 1: Capture, radio-tag, and track adults of five species of Pacific
Salmon in the Middle and Upper Susitna River in proportion to their
abundance. Capture and tag Chinook, Coho, and Pink salmon in the Lower
Susitna and Yentna rivers. ...............................................................................30
5.1.1. Fish Capture and Fish Tagging ......................................................31
5.1.2. Numbers and Size of Marked and Unmarked Fish Recovered at
Selected Locations .........................................................................35
5.1.3. Assessing Any Stock- and Size-selective Capture .........................37
5.1.4. Examining Handling-Induced Changes in Behavior .....................42
5.2. Objective 2: Determine the migration behavior and spawning locations of
radio-tagged fish in the Lower, Middle, and Upper Susitna River ..................44
5.2.1. Chinook Salmon.............................................................................44
5.2.2. Chum Salmon.................................................................................47
5.2.3. Coho Salmon ..................................................................................48
5.2.4. Pink Salmon ...................................................................................50
5.2.5. Sockeye Salmon .............................................................................52
5.3. Objective 3: Characterize adult salmon migration behavior and timing within
and above Devils Canyon ................................................................................53
5.3.1. Chinook Salmon.............................................................................53
5.3.2. Sockeye Salmon .............................................................................58
5.3.3. Other Species .................................................................................59
5.4. Objective 4: Use available technology to document salmon spawning
locations in turbid water...................................................................................59
5.4.1. Programmatic Summary ................................................................60
5.5. Objective 6: Generate counts of adult Chinook Salmon spawning in the
Susitna River and its tributaries .......................................................................60
5.5.1. Indian River Escapement Estimate ................................................61
5.5.2. Estimated Abundance of Chinook Salmon Upstream of Devils
Canyon ...........................................................................................62
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page iii October 2015
5.6. Objective 7: Collect tissue samples to support the Fish Genetics Study .........63
5.7. Objective 8: Estimate the system-wide Chinook Salmon escapement and the
Coho Salmon escapement to the Susitna River above the Yentna River, and
the distribution of those fish among tributaries of the Susitna River ..............63
6. Discussion......................................................................................................................... 64
6.1. Chinook ............................................................................................................64
6.1.1. Timing of Migration ......................................................................64
6.1.2. Timing of Spawning ......................................................................65
6.1.3. Distribution to Mainstem and Tributaries ......................................66
6.1.4. Mainstem Habitat and Tributary Use .............................................68
6.1.5. Abundance Estimates .....................................................................70
6.2. Chum ................................................................................................................71
6.2.1. Timing of Migration ......................................................................71
6.2.2. Timing of Spawning ......................................................................71
6.2.3. Distribution to Mainstem and Tributaries ......................................72
6.2.4. Mainstem Habitat and Tributary Use .............................................73
6.2.5. Abundance Estimates .....................................................................74
6.3. Coho .................................................................................................................75
6.3.1. Timing of Migration ......................................................................75
6.3.2. Timing of Spawning ......................................................................75
6.3.3. Distribution to Mainstem and Tributaries ......................................76
6.3.4. Mainstem Habitat and Tributary Use .............................................77
6.3.5. Abundance Estimates .....................................................................78
6.4. Pink ..................................................................................................................79
6.4.1. Timing of Migration ......................................................................79
6.4.2. Timing of Spawning ......................................................................79
6.4.3. Distribution to Mainstem and Tributaries ......................................80
6.4.4. Mainstem Habitat and Tributary Use .............................................81
6.4.5. Abundance Estimates .....................................................................82
6.5. Sockeye ............................................................................................................83
6.5.1. Timing of Migration ......................................................................83
6.5.2. Timing of Spawning ......................................................................83
6.5.3. Distribution to Mainstem and Tributaries ......................................84
6.5.4. Mainstem Habitat and Tributary Use .............................................85
6.5.5. Abundance Estimates .....................................................................86
7. Conclusions ...................................................................................................................... 87
8. Literature Cited .............................................................................................................. 87
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page iv October 2015
9. Tables ............................................................................................................................... 92
10. Figures ............................................................................................................................ 114
LIST OF TABLES
Table 4.3-1. Aerial spawner surveys conducted in the Middle and Upper River by
location and date, 2014. .................................................................................................... 93
Table 5.1-1. Number of adult salmon radio-tagged in the Susitna River Basin from 2012
to 2014, by species, fish size, and tagging location. ......................................................... 94
Table 5.2-1. Classifications for radio-tagged salmon in 2014, by species and release
location. ............................................................................................................................. 95
Table 5.2-2. The proportions of radio-tagged salmon of known destination that were
detected in the Middle and Upper rivers, and that subsequently returned
downstream to enter a Lower River tributary, or that appeared to have a mainstem
destination in the Lower River, 2014. ............................................................................... 98
Table 5.2-3. Farthest upstream detection locations for radio-tagged fish that were
eventually assigned to mainstem or tributary spawning locations downstream of
Lane Station (top panel: fish released in the Lower River; bottom panel: fish
released in the Middle River), 2014. ............................................................................... 100
Table 5.3-1. Number of salmon radio-tagged in the Lower and Middle rivers, and the
number of radio-tagged salmon that were detected at or above the Gateway
Station, above each impediment, and above the proposed dam site, 2014. .................... 101
Table 5.3-2. Details of the radio-tagged salmon that approached or passed the Middle
River impediments, 2014. ............................................................................................... 102
Table 5.3-3. Destinations of radio-tagged salmon that passed each Middle River
impediment, 2014. .......................................................................................................... 106
Table 5.3-4. Dates on which radio-tagged fish were first detected upstream of
Impediment 3 (2012-2014), with corresponding flows as measured at Tsusena and
Gold creeks. .................................................................................................................... 107
Table 5.3-5. Aerial Chinook Salmon spawning escapement surveys. Number of flights,
and date and magnitude of peak counts per stream and survey year. ............................. 108
Table 5.4-1. Survey effort and observations using DIDSON to identify Chinook Salmon
spawning behavior in turbid water, 2014. ....................................................................... 110
Table 6.2-1. Confirmed spawning salmon in slough habitats of the Middle River from
1981 to 1985, and confirmed spawning locations in 2012, 2013, and 2014................... 112
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page v October 2015
LIST OF FIGURES
Figure 3-1. Susitna River watershed showing fish capture sites (fishwheels) and the
locations of fixed-station telemetry receiver sites, 2014. ............................................... 115
Figure 4.1-1. Middle River Segment showing sites for fish capture (Site 1, PRM 124.1;
Site 2, PRM 123.0; and Site 3, PRM 126.0), sonar (ARIS; PRM 124.0), Curry
camp (PRM 124.2), and the Lane Creek (PRM 116.7) and ‘Gateway’ (PRM
130.1) fixed-station receiver sites, 2014. ........................................................................ 117
Figure 4.3-1. Extent of aerial spawner surveys in the Indian River and tributaries in and
above Devils Canyon, 2014. ........................................................................................... 118
Figure 5.1-1. Daily discharge of the Susitna River at the Gold Creek gauge from April to
November in 2012, 2013, and 2014. ............................................................................... 119
Figure 5.1-2. Daily discharge of the Susitna River at the Tsusena Creek gauge from
April to November in 2012, 2013, and 2014. ................................................................. 119
Figure 5.1-3. Median travel speeds of radio-tagged fish in four major river reaches, by
species. ............................................................................................................................ 120
Figure 5.2-1. Classifications for radio-tagged salmon released in the Lower River (left
panels) or Middle River (right panels), by species/life history stage, 2014. .................. 121
Figure 5.2-2. Relative frequencies of tributary use by radio-tagged salmon released in the
Lower River, by species, 2014. Shown as a percentage of all fish classified to a
tributary destination. ....................................................................................................... 122
Figure 5.2-3. Relative frequencies of tributary use by radio-tagged salmon released in the
Middle River, by species, 2014. ...................................................................................... 123
Figure 5.3-1. Daily numbers of radio-tagged large Chinook Salmon that approached and
passed each of the three Middle River impediments in 2014. ........................................ 124
Figure 5.3-2. Daily numbers of radio-tagged small Chinook (top panel) and Sockeye
(bottom panel) salmon that approached and passed Middle River Impediment 1 in
2014................................................................................................................................. 125
Figure 5.3-3. Daily number of radio-tagged Chinook Salmon that held below
Impediment 3 in 2014. .................................................................................................... 126
Figure 5.3-4. Flows (measured at Gold Creek) in 2012, 2013 and 2014, along with
median (solid black line), and the 10th and 90th percentile (dotted lines) historical
flows. ............................................................................................................................... 127
Figure 5.7-1. Destinations for radio-tagged Chinook Salmon released in the Lower River
in 2013. ........................................................................................................................... 128
Figure 5.7-2. Destinations for radio-tagged Chinook Salmon released in the Lower River
in 2014. ........................................................................................................................... 129
Figure 5.7-3. Destinations for radio-tagged Coho Salmon released in the Lower River in
2013 (yellow circles). ...................................................................................................... 130
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page vi October 2015
Figure 5.7-4. Destinations for radio-tagged Coho Salmon released in the Lower River in
2014 (yellow circles). ...................................................................................................... 131
LIST OF APPENDICES
Appendix A: Fish Capture and Tagging
Table A-1. Number of salmon caught and radio-tagged at two fishwheel sites and from
gillnets in the Lower River, PRM 33.4–34.2, 2014. ........................................................... 1
Table A-2. Number of Chinook Salmon caught and radio-tagged at fishwheel sites and in
gillnets in the Yentna River (RM 6 and RM 18), 2014. ..................................................... 1
Table A-3. Number of salmon radio-tagged at three fishwheel sites and in gillnets in the
Middle River, by size category, 2014. ................................................................................ 2
Table A-4. Number of salmon caught in the Lower River and Yentna River and their
length statistics, 2014. ......................................................................................................... 3
Table A-5. Number of salmon captured at three fishwheel sites and in gillnets in the
Middle River, by size category, 2014. ................................................................................ 4
Table A-6. Number of fish caught, tagged, and biosampled at the Middle River
fishwheels, 2014. ................................................................................................................ 5
Table A-7. Daily fishing effort and the number of salmon caught and radio-tagged
during gillnet operations in the vicinity of Curry, 2014. .................................................... 6
Table A-8. Summary of run-timing and catch information for salmon captured in
fishwheels located in the Middle River near Curry, by year and species. .......................... 7
Table A-9. Comparisons between the cumulative length-frequency distributions of fish
sampled in the Lower River and Yentna River using the Kolmogorov-Smirnov
(KS) two-sample test, 2014................................................................................................. 8
Table A-10. Comparisons between the cumulative length-frequency distributions of fish
sampled in the Middle River using the Kolmogorov-Smirnov (KS) two-sample
test, 2014. ............................................................................................................................ 9
Figure A-1. Daily fishing effort (hours) at two fishwheel sites in the Lower River, 2014. ......... 10
Figure A-2. Daily gillnet effort (hours) in the Lower River, by mesh size, 2014. ...................... 10
Figure A-3. Daily fishing effort (hours) at four fishwheel sites in the Yentna River, 2014. ....... 11
Figure A-4. Daily gillnet effort (hours) during tagging (top panel) and recovery (bottom
panel) operations in the Yentna River, by mesh size, 2014. ............................................. 12
Figure A-5. Daily fishing effort (hours) and rotational speed (RPM) at three fishwheel
sites in the Middle River, 2014. ........................................................................................ 12
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page vii October 2015
Figure A-6. Daily number of radio tags applied to adult salmon species captured at two
fishwheel sites and in gillnets in the Lower River, 2014. ................................................. 13
Figure A-7. Daily number of radio tags applied to adult salmon species captured at two
fishwheel sites and in gillnets in the Yentna River (RM 6), 2014. ................................... 14
Figure A-8. Daily number of radio tags applied to adult salmon species captured at three
fishwheel sites and in gillnets in the Middle River, 2014. ................................................ 15
Figure A-9. Daily catch-per-unit-effort of adult salmon species at the Lower River
fishwheels, and the Susitna River discharge at Sunshine, 2014. ...................................... 16
Figure A-10. Daily catch-per-unit-effort for Chinook and Coho salmon at the Yentna
River fishwheels, by site, 2014. ........................................................................................ 17
Figure A-11. Number of radio tags deployed in species of salmon at the Middle River
fishwheels in 2014 relative to fishwheel catches in 2012, 2013, and 2014. ..................... 18
Figure A-12. Daily catch-per-unit-effort at the Middle River fishwheels, by species, and
the Susitna River discharge at Gold Creek, 2014. ............................................................ 19
Figure A-13. Comparison of Chinook Salmon catches (top panel), relative proportion of
catches (middle panel), and cumulative proportion of catches (bottom panel), at
the Middle River fishwheels near Curry, by year. ............................................................ 20
Figure A-14. Comparison of Chum Salmon catches (top panel), relative proportion of
catches (middle panel), and cumulative proportion of catches (bottom panel), at
the Middle River fishwheels near Curry, by year. ............................................................ 21
Figure A-15. Comparison of Coho Salmon catches (top panel), relative proportion of
catches (middle panel), and cumulative proportion of catches (bottom panel), at
the Middle River fishwheels near Curry, by year. ............................................................ 22
Figure A-16. Comparison of Pink Salmon catches (top panel), relative proportion of
catches (middle panel), and cumulative proportion of catches (bottom panel), at
the Middle River fishwheels near Curry, by year. ............................................................ 23
Figure A-17. Comparison of Sockeye Salmon catches (top panel), relative proportion of
catches (middle panel), and cumulative proportion of catches (bottom panel), at
the Middle River fishwheels near Curry, by year. ............................................................ 24
Figure A-18. Daily sampling effort, and the amount of imagery reviewed (review effort),
for an ARIS sonar unit operated immediately downstream of the fishwheel at Site
1 in the Middle River, 2014. ............................................................................................. 25
Figure A-19. Catch-per-unit-effort, or the number of targets counted per hour of imagery
reviewed, on the ARIS unit located immediately downstream of the Site 1
fishwheel, 2014. ................................................................................................................ 25
Figure A-20. Comparison of the catch-per-unit-effort of adult salmon at the Site 1
fishwheel and concurrent net upstream counts of fish on the ARIS unit located
immediately downstream of the fishwheel, 2014. ............................................................ 26
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page viii October 2015
Figure A-21. Relative percentage of fish counted using ARIS at Site 1 as a function of
the distance where they were first detected in the field of view, by time period,
2014................................................................................................................................... 26
Figure A-22. Diel migration of upstream-moving fish counted using ARIS at Site 1, by
size category and time period, 2014. ................................................................................ 27
Figure A-23. Cumulative length-frequency distributions for Chinook Salmon captured in
the Lower River, by capture site, 2014. ............................................................................ 28
Figure A-24. Cumulative length-frequency distributions for Chinook and Pink salmon
caught and radio-tagged in the Lower River, by species, 2014. ....................................... 28
Figure A-25. Cumulative length-frequency distributions for Chinook Salmon radio-
tagged in the Lower River and inspected and recaptured at the Deshka River and
Montana Creek weir sites, 2014........................................................................................ 29
Figure A-26. Cumulative length-frequency distributions for Chinook Salmon captured at
RM 6 (left panel) and RM 18 (right panel) in the Yentna River, 2014. ........................... 29
Figure A-27. Cumulative length-frequency distributions for Chinook Salmon measuring
50 cm METF or greater that were caught and dart-tagged in the Yentna River
(RM 6), 2014. .................................................................................................................... 30
Figure A-28. Cumulative length-frequency distributions for Chinook Salmon dart-tagged
at Yentna RM 6 and inspected and recaptured at Yentna RM 18 (fishwheels and
gillnets combined), 2014. .................................................................................................. 30
Figure A-29. Cumulative length-frequency distributions for salmon captured in the
Middle River fishwheels, by species and capture site, 2014. ........................................... 31
Figure A-30. Cumulative length-frequency distributions for salmon caught and radio-
tagged in the Middle River, by species, 2014. .................................................................. 32
Appendix B: Daily Fish Passage at Weir and Sonar Sites in the Lower and Middle Rivers
Table B-1. Deshka River weir daily passage rates and tag recaptures, by species, 2014. ............. 1
Table B-2. Montana Creek weir daily passage rates and tag recaptures, by species, 2014. .......... 5
Table B-3. Length statistics for tagged and untagged adult salmon sampled at the Deshka
River and Montana Creek weirs, by species, 2014. ............................................................ 9
Table B-4. Daily amount of video imagery collected and reviewed at the Indian River
weir, and the net upstream count of fish, by species, 2014. ............................................... 9
Table B-5. Daily number of Chinook Salmon inspected for tags, and the number of dart-
tag recaptures, at RM 18 sites on the Yentna River, 2014. ............................................... 10
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page ix October 2015
Appendix C: Fixed-station Receiver Sites (Setup and Performance) and Mobile-tracking
Survey Effort
Table C-1. Location and antenna orientation of fixed-station receivers in the Susitna
River drainage, 2014. .......................................................................................................... 1
Table C-2. Monitoring efficiency (percent operational) of fixed-station receivers in the
Lower River Basin in 2014, by week. ................................................................................. 3
Table C-3. Monitoring efficiency (percent operational) of fixed-station receivers in the
Middle and Upper River basins in 2014, by week. ............................................................. 4
Table C-4. List of the aerial telemetry surveys conducted in 2014, by location, date, and
vehicle type (helicopter, fixed-wing). ................................................................................. 5
Appendix D: Spawning Destinations
Table D-1. Summary of monitoring effort at potential spawning sites, by species, as part
of the Habitat Suitability Criteria (HSC) component of the Fish and Aquatics
Instream Flow Study (RSP Section 8.5), 2014. .................................................................. 1
Table D-2. Summary of monitoring effort at potential spawning sites for Chinook
Salmon in the Middle River, 2014. ..................................................................................... 2
Table D-3. Summary of monitoring effort at potential spawning sites for Chum Salmon
in the Middle River, 2014. .................................................................................................. 3
Table D-4. Summary of monitoring effort at potential spawning sites for Coho Salmon in
the Middle River, 2014. ...................................................................................................... 4
Table D-5. Summary of monitoring effort at potential spawning sites for Pink Salmon in
the Middle River, 2014. ...................................................................................................... 5
Table D-6. Summary of monitoring effort at potential spawning sites for Sockeye
Salmon in the Middle River, 2014. ..................................................................................... 6
Table D-7. Details of impediment-passage events for radio-tagged fish, 2014. ............................ 7
Table D-8. Number of Chinook Salmon counted during aerial spawner surveys, by
location and survey period, 2014. ..................................................................................... 11
Table D-9. Summary of weather variability during the adult salmon aerial spawner
surveys in the Middle and Upper rivers, 2014. ................................................................. 12
Table D-10. Summary of survey condition rankings during the adult salmon aerial
spawner surveys in the Middle and Upper rivers, 2014. ................................................... 12
Figure D-1. Destinations for radio-tagged Chinook Salmon released in the Lower River
in 2012-2014. .................................................................................................................... 13
Figure D-2. Destinations for radio-tagged Chinook Salmon released in the Middle River
in 2012-2014. .................................................................................................................... 14
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page x October 2015
Figure D-3. Destinations for radio-tagged Chum Salmon released in the Lower River in
2012................................................................................................................................... 15
Figure D-4. Destinations for radio-tagged Chum Salmon released in the Middle River in
2012-2014. ........................................................................................................................ 16
Figure D-5. Destinations for radio-tagged Coho Salmon released in the Lower River in
2012-2014. ........................................................................................................................ 17
Figure D-6. Destinations for radio-tagged Coho Salmon released in the Middle River in
2012-2014. ........................................................................................................................ 18
Figure D-7. Destinations for radio-tagged Pink Salmon released in the Lower River in
2012-2014. ........................................................................................................................ 19
Figure D-8. Destinations for radio-tagged Pink Salmon released in the Middle River in
2012-2014. ........................................................................................................................ 20
Figure D-9. Destinations for radio-tagged Sockeye Salmon released in the Lower River
in 2012. ............................................................................................................................. 21
Figure D-10. Destinations for radio-tagged Sockeye Salmon released in the Middle River
in 2012-2014. .................................................................................................................... 22
Figure D-11. Potential mainstem spawning sites for radio-tagged Chinook Salmon in the
Lower River, PRM 40–104, 2012-2014. .......................................................................... 23
Figure D-12. Potential mainstem spawning sites for radio-tagged Chinook Salmon in the
Middle River (red and yellow dots), PRM 103–157, 2012 - 2014. .................................. 24
Figure D-13. Potential mainstem spawning sites for radio-tagged Chum Salmon in the
Lower River, PRM 103–157, 2012 - 2014. ...................................................................... 25
Figure D-14. Potential mainstem spawning sites for radio-tagged Chum Salmon in the
northern half of the Middle River, PRM 40–104, 2012 - 2014. ....................................... 26
Figure D-15. Potential mainstem spawning sites for radio-tagged Chum Salmon in the
southern half of the Middle River, PRM 103–157, 2012 -2014. ...................................... 27
Figure D-16. Potential mainstem spawning sites for radio-tagged Coho Salmon in the
Lower River, PRM 40–104, 2012 - 2014. ........................................................................ 28
Figure D-17. Potential mainstem spawning sites for radio-tagged Coho Salmon in the
Middle River, PRM 103–157, 2012 - 2014. ..................................................................... 29
Figure D-18. Potential mainstem spawning sites for radio-tagged Pink Salmon in the
Lower River, PRM103–157, 2012 -2014. ........................................................................ 30
Figure D-19. Potential mainstem spawning sites for radio-tagged Pink Salmon in the
Middle River, PRM 103–157, 2012 - 2014. ..................................................................... 31
Figure D-20. Potential mainstem spawning sites for radio-tagged Sockeye Salmon in the
Middle River, PRM 103–157, 2012 - 2014. ..................................................................... 32
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Page xi October 2015
Appendix E: Radio Tag Recoveries
Table E-1. Radio tag recovery information for fish released in the Lower River and
Yentna River, 2014. ............................................................................................................ 1
Table E-2. Radio tag recovery information for fish released in the Middle River, 2014. ............. 4
Appendix F: Tracking Histories of Chinook Salmon Above Impediment 3
Table F-1. Summary of migration and spawning behavior for radio-tagged Chinook
Salmon after they passed Impediment 3, 2012–2014. ........................................................ 1
Figure F-1. Tracking history of a radio-tagged Chinook Salmon (tag #537) that was
detected above Impediment 3, PRM 123–167, 2014. ......................................................... 2
Figure F-2. Tracking history of a radio-tagged Chinook Salmon (tag #787) that was
detected above Impediment 3, PRM 97–245, 2014. ........................................................... 3
Figure F-3. Tracking history of a radio-tagged Chinook Salmon (tag #27) that was
detected above Impediment 3, 2012. .................................................................................. 4
Figure F-4. Tracking history of a radio-tagged Chinook Salmon (tag #52) that was
detected above Impediment 3, 2012. .................................................................................. 5
Figure F-5. Tracking history of a radio-tagged Chinook Salmon (tag #94) that was
detected above Impediment 3, 2012. .................................................................................. 6
Figure F-6. Tracking history of a radio-tagged Chinook Salmon (tag #104) that was
detected above Impediment 3, 2012. .................................................................................. 7
Figure F-7. Tracking history of a radio-tagged Chinook Salmon (tag #113) that was
detected above Impediment 3, 2012. .................................................................................. 8
Figure F-8. Tracking history of a radio-tagged Chinook Salmon (tag #219) that was
detected above Impediment 3, 2012. .................................................................................. 9
Figure F-9. Tracking history of a radio-tagged Chinook Salmon (tag #246) that was
detected above Impediment 3, 2012. ................................................................................ 10
Figure F-10. Tracking history of a radio-tagged Chinook Salmon (tag #257) that was
detected above Impediment 3, 2012. ................................................................................ 11
Figure F-11. Tracking history of a radio-tagged Chinook Salmon (tag #266) that was
detected above Impediment 3, 2012. ................................................................................ 12
Figure F-12. Tracking history of a radio-tagged Chinook Salmon (tag #359) that was
detected above Impediment 3, 2012. ................................................................................ 13
Figure F-13. Tracking history of a radio-tagged Chinook Salmon (tag #5005) that was
detected above Impediment 3, 2012. ................................................................................ 14
Figure F-14. Tracking history of a radio-tagged Chinook Salmon (tag #5019) that was
detected above Impediment 3, 2012. ................................................................................ 15
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Figure F-15. Tracking history of a radio-tagged Chinook Salmon (tag #241) that was
detected above Impediment 3, 2013. ................................................................................ 16
Figure F-16. Tracking history of a radio-tagged Chinook Salmon (tag #272) that was
detected above Impediment 3, 2013. ................................................................................ 17
Figure F-17. Tracking history of a radio-tagged Chinook Salmon (tag #395) that was
detected above Impediment 3, 2013. ................................................................................ 18
Appendix G: Counts of Chinook Salmon at Watana Canyon Using Sonar
Table G-1. Location details for Watana Canyon sonar sites near PRM 187.1 in 2014. ................ 9
Table G-2. Operating frequencies and data collection parameters used for the ARIS
monitoring stations at Watana Canyon in 2014. ................................................................. 9
Table G-3. Percent coverage for each sonar station and combined based on wetted
channel width, wetted edge to sonar, and ensonified range at sample sites near
PRM 187.1 in Watana Canyon. .......................................................................................... 9
Table G-4. Sample effort, CPUE, and net upstream count of fish measuring 50 cm or
greater at two ARIS units located at PRM 187.1 in the Upper River, 2014. .................... 10
Table G-5. Discharge estimates based on spatial integration of velocity data for ADCP
surveys conducted in the Watana Canyon in August, 2014. ............................................. 12
Table G-6. Daily data collection parameters at the Watana Canyon sonar sites, 2014. .............. 13
Figure G-1. Photograph of the Susitna River immediately downstream of the proposed
Watana Dam Site (PRM 187.1) showing the location of the river left and river
right sonar sites and the wetted channel width. ................................................................ 15
Figure G-2. Photographs showing the ARIS mounts deployed at the left bank (left) and
right bank (right) monitoring stations. .............................................................................. 15
Figure G-3. Photographs showing the environmental boxes used to house the ARIS
systems electronic components, and power sources (battery banks are inside
action packers) for the left bank (left) and right bank (right) monitoring stations. .......... 16
Figure G-4. Still images from ARIS data showing the cobble substrate (light-colored
structure) along the left bank (left) and right bank (right) fields-of-view. ....................... 16
Figure G-5. Ortho image showing the ensonified wetted width coverage of each ARIS
unit near the Watana Dam Site, 2014. .............................................................................. 17
Figure G-6. Screen shots of Right Bank ARIS data showing echograms (left) and still
sonar imagery (right) for a resident fish (top) and Chinook Salmon (bottom). ................ 18
Figure G-7. Daily sampling effort at two ARIS sonar units located at PRM 187.1 in the
Upper River, 2014. ............................................................................................................ 19
Figure G-8. Bathymetry profiles derived from ADCP data for transects aligned with
ARIS sampling locations (PRM 187.1). ........................................................................... 20
Figure G-9. Net upstream count of fish measuring 50 cm or greater at two ARIS sonar
units located at PRM 187.1 in the Upper River, 2014. ..................................................... 21
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Figure G-10. Diel migration of fish measuring 50 cm or greater counted at two ARIS
sonar units located at PRM 187.1 in the Upper River. ..................................................... 21
Figure G-11. Percent of fish measuring 50 cm or greater counted at two ARIS sonar
units located at PRM 187.1 in the Upper River as a function of distance from the
sonar units, 2014. .............................................................................................................. 22
Figure G-12. Series of velocity profiles collected along transects using an ADCP at
Watana Canyon (PRM 187.1) in 2014. Transects are arranged from upstream
(top) to downstream (bottom) to allow for best presentation of the transect-to-
transect channel morphology. Range of sonar stations is shown for the River Left
site at Transect 3 and River Right site at Transect 6. ........................................................ 22
Figure G-13. Individual velocity profile for Transect 3 in Watana Canyon (PRM 187.1)
collected with an ADCP in 2014. This profile corresponds to the location of the
sonar station on River Left (ensonified zone illustrated). ................................................. 23
Figure G-14. Individual velocity profile for Transect 6 in Watana Canyon (PRM 187.1)
collected with an ADCP in 2014. This profile corresponds to the location of the
sonar station on River Right (ensonified zone illustrated). ............................................... 23
Figure G-15. Bathymetry in Watana Canyon (PRM 187.1) based on seven serial ADCP
transects, 2014................................................................................................................... 24
Appendix H: Chinook Salmon – Indian River Escapement Estimate for Chinook Salmon
Table H-1. Number of Chinook Salmon counted during aerial spawner surveys in the
Indian River, and the number of radio-tagged large Chinook Salmon detected, by
tag site, 2014. ...................................................................................................................... 3
Table H-2. Summary of AUC abundance estimate, mark rate at the Middle River tag site,
and the expected number of fish passed the Watana Dam sonar site, 2014. ...................... 5
Figure H-1. Number of Chinook Salmon counted during aerial spawner surveys above
Bridge 1 in the Indian River, 2014. ..................................................................................... 5
Figure H-2. Relative frequency of residence times (days) for radio-tagged Chinook
Salmon above Bridge 1 in the Indian River, 2014. ............................................................. 6
Appendix I: Estimate the System-wide Chinook Salmon Escapement and the Distribution
of Those Fish Among Tributaries of the Susitna River
Table I-1. Diagnostic tests for mark-recapture data for mainstem Susitna River Chinook
Salmon measuring 50.0–78.5 cm METF, 2014. ............................................................... 11
Table I-2. Diagnostic tests for mark-recapture data for mainstem Susitna River Chinook
Salmon measuring 78.5 cm METF or greater, 2014. ........................................................ 12
Table I-3. Estimated abundance, number of radio tags deployed, and relative weights
(number of spawners per tag) used to estimate abundance within size stratum for
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Chinook Salmon spawning upstream from the lower mainstem tagging site in the
Susitna River, 2014. .......................................................................................................... 13
Table I-4. Chinook Salmon measuring 50 cm METF or greater spawning distributions,
based on weighted abundance (Table I-3), in the mainstem Susitna River above
the Lower River tagging site, 2014. .................................................................................. 13
Table I-5. Diagnostic tests for mark-recapture data for Yentna River Chinook Salmon
>50 cm METF, 2014a........................................................................................................ 14
Table I-6. Chinook Salmon spawning distributions in the Yentna River above the RM 6
tagging site, 2014. ............................................................................................................. 15
Table I-7. Diagnostic tests for mark-recapture data for mainstem Susitna River Coho
Salmon 40-55 cm METF, 2014a. ...................................................................................... 16
Table I-8. Diagnostic tests for mark-recapture data for mainstem Susitna River Coho
Salmon >55 cm METF, 2014a. ......................................................................................... 17
Table I-9. Estimated abundance, number of radio tags deployed, and relative weights
(number of spawners per tag) used to estimate abundance within size stratum for
Coho Salmon spawning upstream from the lower mainstem tagging site in the
Susitna River, 2014. .......................................................................................................... 18
Table I-10. Coho Salmon spawning distributions, based on weighted abundance (Table I-
3), in the mainstem Susitna River above the lower river tagging site, 2014. ................... 18
Figure I-1. Empirical cumulative distribution functions (ECDF) of length (in mm) of
Chinook Salmon (METF ≥ 50 cm) marked during first event sampling at the
lower mainstem Susitna River tagging site and all recaptures during second event
sampling at the Deshka River and Montana Creek weirs, 2014. ........................................ 1
Figure I-2. Empirical cumulative distribution functions (ECDF) of length (in
millimeters, mm) of Chinook (METF ≥ 500 mm) inspected for marks and all
recaptured salmon during second event sampling at the Deshka River weir, 2014. .......... 2
Figure I-3. Empirical cumulative distribution functions (ECDF) of length (in mm) of
Chinook Salmon (METF ≥ 500 mm) inspected for marks and all recaptured
salmon during second event sampling at the Montana Creek weir, 2014. ......................... 3
Figure I-4. The 4-day lag between total weir count and radio-tagged Chinook Salmon at
the Deshka River weir, 2014. .............................................................................................. 4
Figure I-5. Empirical cumulative distribution functions of METF length (mm) of all
Chinook Salmon (> 500 mm) marked during first event at the lower Yentna River
tagging site at RM 6 and of all salmon recaptured during second event sampling at
RM 18 of the lower Yentna River, 2014. ............................................................................ 5
Figure I-6. Empirical cumulative distribution functions of METF length (mm) of
Chinook Salmon (> 500 mm) inspected for marks during second event sampling
at the Yentna RM 18 east fishwheel, and all salmon recaptured during inspection
in 2014. ............................................................................................................................... 6
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Figure I-7. Empirical cumulative distribution functions of METF length (mm) of
Chinook Salmon (>500 mm) inspected for marks during second event sampling at
the Yentna RM 18 west fishwheel, and all salmon recaptured during inspection in
2014..................................................................................................................................... 7
Figure I-8. Empirical cumulative distribution functions of METF length (mm) of
Chinook Salmon (>500 mm) inspected for marks during second event sampling
(pooled data) and all salmon recaptured during inspection at Yentna RM 18 in
2014..................................................................................................................................... 8
Figure I-9. Timing at Yentna River second event fishwheels (RM 18) of all fish caught
>500 mm METF and of recaptures. .................................................................................... 9
Figure I-10. Empirical cumulative distribution functions of METF length (mm) of all
Coho Salmon (> 400 mm) marked during first event at the lower mainstem
Susitna River tagging site and of all salmon recaptured during second event
sampling at the Deshka River and Montana Creek weirs during second event,
2014................................................................................................................................... 10
Figure I-11. Empirical cumulative distribution functions of METF length (mm) of Coho
Salmon (> 400 mm) inspected for marks during second event sampling at the
Deshka River weir, 2014 and of all salmon recaptured during inspection. ...................... 11
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LIST OF ACRONYMS, ABBREVIATIONS, AND DEFINITIONS
Abbreviation Definition
ADCP acoustic Doppler current profiler
ADF&G Alaska Department of Fish and Game
AEA Alaska Energy Authority
ARIS Adaptive Resolution Imaging Sonar
ATS Advanced Telemetry Systems, Inc.
AUC area under the curve
cfs cubic feet per second
cm Centimeter
CM Complete Mixing (test)
CPUE catch per unit effort
DIDSON Dual Frequency Identification Sonar
ECDF Empirical cumulative distribution function
EP Equal Proportion (test)
FERC Federal Energy Regulatory Commission
FOV field-of-view
ft Feet
ft/s feet per second
g Gram
GIS geographic information system
GPS global positioning system
HSC Habitat Suitability Criteria
ILP Integrated Licensing Process
in Inch
ISR Initial Study Report
km Kilometer
KS Kolmogorov-Smirnov
m Meter
mi Mile
m/s meters per second
METF mid-eye to fork
MHz Megahertz
mm Millimeter
NTU nephelometric turbidity units
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Abbreviation Definition
oz Ounce
PRM Project River Mile
RM river mile
RPM revolutions per minute
RSP Revised Study Plan
SMC Sound Metrics Corporation
SPD study plan determination
TL total length
USGS United States Geological Survey
W Watt
V Volt
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1. INTRODUCTION
This Salmon Escapement Study, Section 9.7 of the Revised Study Plan (RSP) approved by the
Federal Energy Regulatory Commission (FERC or Commission) for the Susitna-Watana
Hydroelectric Project, FERC Project No. 14241, focuses on characterizing the current
distribution, abundance, habitat use, and migratory behavior of all species of adult anadromous
salmon (Oncorhynchus spp.) across mainstem river habitats and select tributaries above the
Three Rivers Confluence (i.e., confluence of the Susitna, Chulitna, and Talkeetna rivers).
A summary of the development of this study, together with the Alaska Energy Authority’s
(AEA) implementation of it through the 2013 study season, appears in Part A, Section 1 of the
Initial Study Report (ISR) filed with FERC in June 2014. As required under FERC’s regulations
for the Integrated Licensing Process (ILP), the ISR describes AEA’s “overall progress in
implementing the study plan and schedule and the data collected, including an explanation of any
variance from the study plan and schedule.” (18 CFR 5.15(c)(1)).
Since filing the ISR in June 2014, AEA has continued to implement the FERC-approved plan for
the Salmon Escapement Study. For example:
On September 30, 2014, AEA filed a Technical Memorandum with FERC to describe
part of the methods, variances, and preliminary results of the 2014 Salmon Escapement
Study (AEA 2014a). The methods and variances described therein were focused on
activities conducted in the Middle and Upper rivers, and preliminary results were focused
on Chinook Salmon (O. tshawytscha).
On October 15, 2014, AEA held an ISR meeting for the Salmon Escapement Study.
In furtherance of the next round of ISR meetings and FERC’s SPD expected in 2016, this report
contains a comprehensive discussion of results of the Salmon Escapement Study from the
beginning of AEA’s study program in 2012, through the end of calendar year 2014. It describes
the methods and results of the Salmon Escapement Study, and explains how all Study Objectives
set forth in the Commission-approved Study Plan have been met. Accordingly, with this report,
AEA has now completed all field work, data collection, data analysis, and reporting for this
study.
2. STUDY OBJECTIVES
The study objectives were established in RSP Section 9.7.1.2, and include:
1) Capture, radio-tag, and track adults of five species of Pacific salmon (i.e., Chinook,
Chum (O. keta), Coho (O. kisutch), Pink (O. gorbuscha), and Sockeye (O. nerka)
salmon) in the Middle and Upper Susitna River in proportion to their species-specific
abundance. Capture and tag Chinook, Coho, and Pink Salmon in the Lower Susitna
River.
2) Characterize the migration behavior and spawning locations of radio-tagged salmon
in the Lower, Middle, and Upper Susitna River.
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3) Characterize adult salmon migration behavior and timing within and above Devils
Canyon.
4) If shown to be an effective sampling method, and where feasible, use sonar to aid in
documenting salmon spawning locations in turbid water in 2013 and 2014.
5) Compare historical and current data on run timing, distribution, relative abundance,
and specific locations of spawning and holding salmon.
6) Generate counts of adult Chinook Salmon spawning in the Susitna River and its
tributaries to estimate the proportions of fish with tags for populations in the
watershed.
7) Collect tissue samples to support the Fish Genetic Baseline Study (Study 9.14).
8) Estimate the system-wide Chinook Salmon escapement to the entire Susitna River,
the Coho Salmon escapement to the Susitna River above the confluence with the
Yentna River, and the distribution of Chinook, Coho, and Pink salmon among
tributaries of the Susitna River (upstream of Yentna River confluence) in 2013 and
2014.
3. STUDY AREA
As established by RSP Section 9.7.3, the study area encompassed the Susitna River from Cook
Inlet upstream to the Oshetna River, or as far upstream as Chinook Salmon were detected (Figure
3-1), with an emphasis on wherever salmon spawned in mainstem habitats of the Susitna River.
The mainstem Susitna River was divided into three segments: the Lower River (Project River
Mile [PRM] 33–102.4), Middle River (PRM 102.4–187.1), and Upper River (PRM 187.1–
261.3). RSP Section 9.7.3 used Historical River Miles (RM) which were: Lower River (RM 30–
98), Middle River (RM 98–184), and Upper River (RM 184–260). Devils Canyon extends from
approximately PRM 153.4 to PRM 166.1 (RM 150 to 163, respectively). Within Devils Canyon,
the channel constricts and increases in vertical gradient to form three potential fish passage
impediments (referred to as Impediments 1, 2, and 3) that may block or delay fish passage (see
Section 3.2 in AEA 2013a for more detail on the impediments).
4. METHODS
Descriptions of the study methods are organized below by objective. This was a multi-year
study initiated in 2012 (AEA 2012, 2013a, 2014a,c). The description of the methods below is
specific to the 2014 implementation of the study.
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4.1. Objective 1: Capture, radio-tag, and track adults of five species
of Pacific salmon in the Middle and Upper Susitna River in
proportion to their abundance. Capture and tag Chinook,
Coho, and Pink salmon in the Lower Susitna and Yentna rivers.
In 2014, the study team implemented the methods with respect to Objective 1 as described in the
Study Plan, with the exception of modifications described in Section 7.1.2 of the ISR and
variances explained below (Section 4.1.6). Tasks to address Objective 1 were listed in RSP
Section 9.7.4.1.
4.1.1. Fish Capture
4.1.1.1. Lower River
In the Lower River, two fishwheels and gillnets were used to capture adult salmon for tagging in
2014. Capture sites were located approximately 1–2 river miles upstream of the Yentna River
confluence. The fishwheels were operated from May 22 to August 26, at locations that were
fished in 2010–2013 (Figure 3-1). One fishwheel operated on the west bank of the Lower River
at PRM 33.4 for 1,153 hours, and the second fishwheel operated on the east bank at PRM 34.2
for 1,154 hours (Figure A-1). From May 22 to June 28, gillnets were fished in the vicinity of the
fishwheels for a total of 79.2 hours (Figure A-2). The gillnet sampling was conducted to
increase the probability of capture for larger Chinook Salmon, as it was expected that fishwheels
would provide length-biased samples favoring smaller fish at this site (see ISR Part A
Appendix I). The gillnets were 5.5 inch (in; stretch) or 7.5 in mesh, multi-strand web, 50–150
feet (ft) long, and 10–12 or 15–17 ft deep. Fifty-eight percent of the effort was with 7.5-in mesh
and 42 percent with 5.5-in mesh.
4.1.1.2. Yentna River
In addition, two fishwheels and gillnets were used on the lower Yentna River (RM 6) to capture
adult salmon for tagging in 2014. Capture sites were in the same locations as had been operated
for three decades (Figure 3-1). One fishwheel operated on the south bank of the Yentna River
(RM 6) for 539 hours from May 22 to June 25, and the second fishwheel operated on the north
bank of the Yentna River (RM 6) for 529 hours from May 22 to June 25 (Figure A-3). There
was effort for both fishwheels every day in 2014 until June 26, and both fishwheels achieved the
targeted effort (16 hours/day) on most days. From May 22 to June 25, gillnets (5.5 and 7.5-in
mesh) were fished in the vicinity of the fishwheels for a total of 281.8 hours (effort was split 53
and 47 percent between mesh sizes, respectively; Figure A-4).
The Study Plan provided that weirs would be used as a recapture method to support a two-event
capture-recapture experiment to estimate abundance of Chinook Salmon in the Yentna River
(RSP Section 9.7.4.8). In 2013, no suitable weir sites could be found. ISR Part C Section
7.1.2.6.1 indicated that the study team would modify the Study Plan and use fishwheels and
gillnets for tag recapture in 2014. In 2014, a new site for two fishwheels and gillnetting was
established on the Yentna River at RM 18 to recapture fish tagged at Yentna RM 6 (Figure 3-1).
One fishwheel operated on the west bank of the Yentna River (RM 18.8) for 1,525 hours from
May 24 to August 27, and the second fishwheel operated on the east bank of the Yentna River
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(RM 18.6) for 1,536 hours from May 24 to August 27 (Figure A-3). There was effort for both
fishwheels on 96 days in 2014 until August 27, and both fishwheels achieved the targeted effort
(16 hours/day) on 94 days. From May 24 to June 30, gillnets (5.5 and 7.5-in mesh) were fished
in the vicinity of the fishwheels for a total of 230.8 hours (effort was split 46 and 54 percent
between mesh sizes, respectively; Figure A-4).
4.1.1.3. Middle River
In the Middle River, three fishwheels and gillnets were used to capture adult salmon for tagging
in 2014. Two of the fishwheels were operated at the same two locations used in 1981–1985,
2012, and 2013 (sites 1 and 2), and a third fishwheel was operated at a site that was first used in
2013 (site 3; Figures 3-1 and 4.1-1). The addition of a third fishwheel represents a variance from
the Study Plan (RSP Section 9.7.4.1.1): it was added to compensate for the lack of a Devils
Canyon fishwheel (see ISR Section 7.1.2.1.2).
The Middle River fishwheels consisted of two aluminum pontoons, three baskets, and two
partially submerged live tanks for holding fish in river water. A tower and winch assembly were
used to adjust the height of the baskets and ensure that the baskets were fishing within 20
centimeters (cm; 7.9 in) of the river bottom. Net leads were installed between the fishwheels and
adjacent riverbank to direct fish away from the bank and into the path of the fishwheel baskets.
During daylight operations, crews were never away from the fishwheels for more than one hour.
From late June to mid-July, the fishwheels were left unattended overnight (from ~11:30 P.M.
until 9:00 A.M. the following morning).
From June 6 to September 7, the Site 1 fishwheel operated for 1,369 hours (61.3 percent of the
time it was in place) on the west bank of the Susitna River (PRM 124.1; Figure A-5). Excluding
the days it did not operate, daily fishing effort at Site 1 averaged 14.9 hours (range: 8.3–24
hours). The targeted amount of daily fishing effort at Site 1 varied by period: 13 hours from
June 6–11, 15–17 hours from June 12–28, 24 hours from June 29 to July 18, 12 hours from July
19 to August 28, and 10 hours from August 29 to September 7. The Site 1 fishwheel did not
operate during high water and heavy debris loads on June 26, June 27, and part of June 28.
From June 12 to September 7, the Site 2 fishwheel operated for 1,270 hours (60.6 percent of the
time it was in place) on the east bank of the river (PRM 123.0; Figure A-5). Daily fishing effort
averaged 14.8 hours (range: 8.8–24.0 hours). Targeted daily fishing effort varied at Site 2: 15–
17 hours from June 12–29, 24 hours from June 30 to July 18, 12 hours from July 19 to August
28, and 10 hours from August 29 to September 7. The Site 2 fishwheel did not operate during
high water and heavy debris loads on June 26, June 27, and part of June 28.
From June 9 to September 7, the Site 3 fishwheel operated for 1,302 hours (60.2 percent of the
time it was in place) on the west bank of the Susitna River at PRM 126.0 (Figure A-5). Daily
fishing effort averaged 14.8 hours (range: 4.8–24.0 hours). Targeted daily fishing effort varied at
Site 3: 15–17 hours from June 9–29, 24 hours from June 30 to July 18, 12 hours from July 19 to
August 29, and 10 hours from August 30 to September 7. The Site 3 fishwheel was not
operational during high water from June 26–28.
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In 2014, the study team introduced a variance to the Study Plan and used set gillnets to capture
Coho Salmon in September. RSP Section 9.7.4.1.1 stated that only fishwheels would be used to
capture adult salmon for tagging in the Middle River. The FERC SPD recommended that the
Middle River fishwheel operation extend throughout the month of September; however, as
described in ISR Part C Section 7.1.2.1.2, analysis of sonar data from 2013 showed that the
Middle River fishwheels were not effective in September when river discharge and turbidity
decreased substantially from summer conditions. ISR Part C Section 7.1.2.1.2 indicated that the
study team would modify the Study Plan and use a beach seine as an alternative capture method
in September 2014. However, beach seine sites with suitable water depth and velocity, and in
areas where fish were migrating (and not holding), were limited in the vicinity of Curry in 2014.
The study team instead used set gillnets, which can be an effective capture method when a river
is low and clear.
In 2014, Middle River fishwheel operations ended on September 7, and every second day from
September 10 to September 30 set gillnets were used to capture and tag adult Coho Salmon in
the vicinity of Curry. Gillnets used in September were 18.3 m (60 ft) long and consisted of 7.6
cm (3.0 in) or 8.9 cm (3.5 in) multi-strand mesh. Fishing effort in September totaled 150.3
hours, and all sets were made between PRM 121.9 and PRM 126.0. On June 24, a set gillnet was
used for 1.8 hours in the vicinity of Curry. This effort was simply exploratory in nature as crews
investigated a few sites for the presence of Chinook Salmon. The gillnet used in June was 36.6
m (120 ft) long, 3.0 m (10 ft) deep, and had 8.9 cm (3.5 in) multi-strand mesh.
The RSP (Section 9.7.4.1.1) indicated that at least one fishwheel would be operated in Devils
Canyon below the impediments. However, as described in ISR Section 7.1.2.1.2, it was not
feasible.
4.1.2. Radio-tagging
Pulse-coded, extended-range tags by Advanced Telemetry Systems, Inc., (ATS; Isanti, MN,
www.atstrack.com) were applied to a subset of salmon captured in the Lower River, Yentna
River, and Middle River. There were 100 unique codes on each available frequency. Model
F1835B transmitters (16 grams [g; 0.6 ounces (oz)], 30 cm [11.8 in] antenna, 96-day battery life)
were used for small Chinook (mid-eye to fork [METF] length < 50 cm [19.7 in]) and Pink
salmon; Model F1840B tags (22 g [0.8 oz], 30 cm [11.8 in] antenna, 127-day battery life) for
Chum, Coho, and Sockeye salmon; and Model F1845B tags (26 g [0.9 oz], 41 cm [16.1 in]
antenna, 162-day battery life) for large Chinook Salmon (METF ≥ 50 cm [19.7 in]). All
transmitters were equipped with a mortality sensor that changed the signal pattern to an
“inactive” mode for the remainder of the season once the tag became stationary for 24 hours. All
of the radio tags were labeled with return contact information. Each tag was tested immediately
prior to deployment to ensure it was functioning properly upon release.
In the Lower River, only uninjured Chinook Salmon with a METF length of 50 cm (19.7 in) or
greater (herein referred to as ‘large’), and Coho and Pink salmon with METF length of 40 cm
(15.7 in) or greater, were radio-tagged. In the Yentna River, only large Chinook Salmon were
radio-tagged. In the Middle River, large Chinook Salmon; Chinook Salmon measuring 30–49
cm METF (11.8–19.3 in; herein referred to as ‘small’); and Chum, Coho, Pink, and Sockeye
salmon measuring 40 cm METF (15.7 in) or greater in length, were radio-tagged. Unless
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otherwise noted, all subsequent references to adult salmon sizes refer to METF lengths. No
anesthesia was used in order to minimize handling time and tagging effects. Radio tags were
inserted through the fish’s mouth into the stomach using a piece of PVC tubing (1/3-in diameter
and 18 in long), with the tag antenna left to protrude from the mouth. All radio-tagged salmon
were measured to determine METF length (to the nearest centimeter), and Chinook and Coho
salmon were tissue sampled (axillary process) for genetic baselines (see Section 4.7).
Unlike 2013, no salmon captured in the Middle River were sampled for scales (to age) or tagged
with an external mark (i.e., spaghetti tag) in 2014. Eliminating these steps reduced the amount of
handling time and the potential for any effects of handling fish on their post-release behavior.
As stated in ISR Part A Section 4.1.8.3 and ISR Part C Section 7.1.2.1.2, scales would not be
collected in 2014 in light of the fact that size selectivity would be tested (as in 2013) and that fish
were randomly selected for tagging. RSP Section 9.7.4.1.3 indicated that a portion of fish
captured in the Middle River (in excess of those required for radio-tagging) would be spaghetti-
tagged to augment the ability to test assumptions about the representativeness of fish captured in
the fishwheels. However, once the Indian River weir was rendered inoperable in 2014 (see
Section 5.1.2.4 below for more details), it was recognized that there would be limited
opportunity to sample fish on the spawning grounds, so no spaghetti tags were applied at the
Middle River fishwheels. The inoperability of the weir also impacted the ability to assess size
selectivity. Due to this variance, the study team relied on various other means to provide insights
into capture probabilities based on size at the Middle River tag site.
To minimize any effects of holding fish in live tanks, salmon captured during daylight hours
were tagged upon capture. All fish were released immediately after tagging. All fish captured
were inspected for tags.
4.1.3. Tagging Goals
Recent (2012 and 2013) and historical (1981–1985) fishwheel catches, effectiveness, and salmon
run timing guided tag application rates over the season.
As stated in RSP Section 9.7.4.1, the goal for Chinook Salmon in the Lower River was to radio-
tag 300 fish per fishwheel; numbers tagged were 259 salmon from the west bank fishwheel, and
271 from the east bank fishwheel (Table A-1; Figure A-6). The goal for gillnetting was 100
Chinook Salmon, and 129 salmon were actually radio-tagged. For Coho Salmon at the Lower
River site, the goal was to radio-tag 300 fish per fishwheel; numbers tagged were 337 Coho
Salmon from the west bank fishwheel, and 303 fish from the east bank fishwheel (Table A-1;
Figure A-6). The difference between the goals and actual radio-tagging was the result of re-
apportioning radio tags in season according to catches. The number of Pink Salmon tagged was
similar to the tagging goal of 100 fish per fishwheel, with 106 radio-tagged from the west bank
fishwheel, and 92 from the east bank fishwheel (Table A-1; Figure A-6).
The radio-tagging goals for the Yentna River (RM 6) fishwheels were 100 fish per fishwheel;
numbers tagged were 95 salmon from the north bank fishwheel, and 95 from the south bank
fishwheel (Table A-2; Figure A-7). The goal for gillnetting was 100 Chinook Salmon; and 106
salmon were radio-tagged. Occasionally low catches in both fishwheels led to re-apportioning
the radio tags in-season.
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As stated in ISR Section 7.1.2.1.2, the revised goal for the Middle River was to radio-tag 650
Chinook Salmon (550 large and 100 small fish; from an initial goal of 400 large fish as stated in
RSP Section 9.7.4.1). As described in the Study Plan, 200 each of Chum, Coho, Pink, and
Sockeye salmon were targeted for radio-tagging in 2014. All species-specific goals were met or
exceeded with the exception of small Chinook Salmon. Final 2014 radio-tagging numbers in the
Middle River were 622 Chinook (590 large, 32 small), 200 Chum, 230 Coho, 201 Pink, and 200
Sockeye salmon (Table A-3; Figure A-8).
4.1.4. Numbers and Size of Marked and Unmarked Fish at Selected Locations
Fish were randomly selected from the fishwheels for tagging. To assess whether these fish were
representative of all fish in the river, several assumptions were tested for fish tagged at the
Lower River, Yentna River, and Middle River sites, as described in RSP Sections 9.7.4.1.5,
9.7.4.1.7, and 9.7.4.6.
4.1.4.1. Lower River and Yentna River
The assumption that radio-tagged salmon were representative of the population of salmon
passing the tagging sites was evaluated for Chinook (Lower River and Yentna River) and Coho
salmon (Lower River) in the framework of the mark-recapture experimental design.
Heterogeneity in probability of capture was investigated by fish size (METF length), and
spatially and temporally using mark-recapture diagnostic tests described by Seber (1982). These
diagnostic tests, along with model selection procedures based on test results to minimize bias in
estimates of abundance and distribution of spawners, are described more explicitly in Seber
(1982, p. 438–439) and Arnason et al. (1996).
The evaluations of the assumption of equal probability of capture and radio-tagging for all
Chinook or Coho Salmon passing the Lower River tagging site were based on characteristics of
all fish counted passing the Montana Creek and Deshka River weirs and of all marked fish
“recaptured” at these weirs. Three independent tests were performed for data from each weir site
to evaluate equal probability of capture by size and temporally, while spatial tests require d the
data from both weirs. Similar tests for Chinook Salmon, by size and temporally (but not
spatially), were conducted using fish sampled at the tagging and recapture sites on the Yentna
River. No size-selectivity tests were conducted for Pink Salmon radio-tagged in the Lower
River.
4.1.4.1.1. Temporal Equal-Proportions Test: Consistency of Chapman Model
Contingency table analysis was used with the χ2 test for independence to conduct the temporal
Equal-Proportions test (see Appendix I for details). For a weir site, the observations of numbers
of fish passing the weir by day and number of recaptures passing the weir by day were divided
into 2 to 6 pairs of cells by time period with approximately uniform sample sizes in each pair of
cells. For each pair of cells, one contained the number of recaptured fish and the second
contained the number of unmarked fish accounted for in the time period. This analysis
determined if the ratio of marked-unmarked fish observed at each weir site was independent of
time of capture at the weir.
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4.1.4.1.2. Spatial Equal Proportions Test: Consistency of Chapman Model
Contingency table analysis was used to conduct the spatial Equal-Proportions test (see
Appendix I for details). A table (2 rows x 2 columns) containing the numbers of marked and
unmarked fish observed at each of the two weir sites was used. This analysis determined if the
marked-unmarked ratios were independent of weir site.
4.1.4.1.3. Equal Probability of Capture by Size
Equal probability of capture by size was evaluated using the Kolmogorov-Smirnov (KS) two-
sample test (see Appendix I for details). For the Lower River, this test determined if the
distribution of lengths from all fish passing a weir site were similar to recaptured (radio-tagged)
fish passing the weir site. Under the null hypothesis, the probability that a fish was radio-tagged
was independent of the size of the fish, and the cumulative distribution function of the lengths of
all fish passing a weir site were expected to be similar to the function of all recaptured fish
passing that weir site.
4.1.4.2. Middle River
RSP Section 9.7.4.1.5 stated that to test whether Chinook, Chum, and Sockeye salmon passing
the Middle River fishwheels were equally vulnerable to being captured and radio-tagged, fish
would be examined on selected spawning grounds to develop two primary metrics: estimates of
the proportion of fish tagged (mark rate), and the size distributions of tagged and untagged fish.
However, ground-based stream counts and carcass surveys conducted in the first study year
(2012) did not produce adequate samples for generating these metrics (see Section 5.1.3.6 in
AEA 2013a). As an alternative to stream counts and carcass surveys, the study team
implemented a variance to the Study Plan in 2013 (ISR Section 4.1.8.3) and operated a picket
weir on the lower Indian River approximately 1.6 river miles from the confluence with the
Susitna River (Figure 3-1). The weir was designed to free-pass upstream- and downstream-
moving adult fish past underwater video cameras. The weir was located far enough upstream to
minimize the number of fish milling at the weir, yet far enough downstream to ensure that the
majority of fish returning to the river would be available to count passing through the video
chute.
Given the success of the Indian River weir in 2013, the study team proposed that the Study Plan
be modified to include similar methodology (see ISR Part A Section 4.1.5.2) in 2014, as
described in ISR Part C Section 7.1.2.1.2. Unfortunately, the Indian River weir was rendered
inoperable during a flood on June 26, 2014, prior to the onset of the majority of the salmon runs.
For Chinook Salmon, the study team considered various alternatives for estimating mark rates
and decided the best available option was to increase the number of aerial spawner surveys and
aerial telemetry surveys in the Indian River (as described further in Section 4.6.1). Apart from
the weir, there were no viable options available for collecting sufficient spawning ground
samples to estimate the mark rates of Chum and Sockeye salmon, or to directly test for size
selectivity in Chinook, Chum, and Sockeye salmon (the RSP did not call for the same effort on
Coho and Pink salmon). For this reason the study team determined that applying spaghetti tags
to fish in excess of radio-tagging requirements was not necessary. The inability to spaghetti tag
fish in excess of radio-tagging requirements, or to collect spawning ground samples to estimate
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mark rates and assess size selectivity, was a variance to the Study Plan implemented in 2014.
Results from previous study years and the analyses described in the following sections were used
to provide insight with respect to these data gaps and ensure that all project objectives were
addressed.
As explained in ISR Section 4.1.8.3, external sexing of fish was not reliable at the Middle River
fishwheels. Thus, fish sex was not recorded in 2014, a variance from the RSP (Section
9.7.4.1.7).
4.1.4.2.1. Fishwheel Effectiveness Across Time
The main assumption of this study component was that the radio tags were deployed at the
fishwheels in proportion to abundance for each species. To help evaluate this assumption at the
Middle River fishwheels, the relative effectiveness of one Middle River fishwheel (at Site 1) was
determined using sonar, from a ratio of the number of fish caught at the fishwheel to the number
of fish observed using sonar. Sonar was not used at fishwheel sites 2 and 3 because these
locations had steep banks and high river velocities that were not suitable for a fixed-site sonar.
At Site 1, fish were observed with an Adaptive Resolution Imaging Sonar (ARIS) system
operated in close proximity to the fishwheel across multiple time periods and river discharges.
ARIS was also used to qualitatively assess fish approach behavior at the fishwheel relative to
discharge and fish abundance. From June 3–25 and August 29 to September 30, one ARIS unit
operated 24 hours per day on the right bank of the Susitna River immediately downstream of the
Site 1 fishwheel (Figure 4.1-1). Daily review effort varied over the season, and ranged from a
third (20 minutes per hour) of the imagery collected each day being reviewed (e.g., June 18–25,
September 1–30) to all of the imagery collected each day being reviewed (e.g., June 3–17). The
sonar sampling area ranged from 0.7–13.6 m (2.3–44.6 ft) in June and 0.7–14.0 m (2.3–45.9 ft)
in August and September.
The catch-per-unit-effort (CPUE; fish per fishwheel hour) for each fishwheel was compared over
time and across a range of discharges to help evaluate the relative effectiveness of each
fishwheel. For example, at Site 1, CPUE and ARIS data were used inseason to determine
whether operational changes were required in order to increase fishwheel catch rates (e.g., high
ARIS counts at a time of low CPUE suggested the fishwheel was not operating effectively and
operational changes were required).
4.1.4.2.2. Differences Among Stocks
To assess whether fish from a particular spawning area were right or left bank-oriented with
respect to the capture site, the proportion of fish migrating into specific areas was compared with
the collection bank. One concern was that mainstem fish could be more vulnerable to the
fishwheels because they linger or mill upstream and downstream of capture sites. Recaptures of
radio-tagged fish at the tagging site fishwheels provided a good test of whether milling fish were
exposed to greater capture rates. In addition to quantitative and qualitative assessment of
subsequent behavior of these recaptured fish, the final destinations (mainstem/tributary) of
recaptured fish were compared with other tagged fish to determine whether fish that spawned in
the mainstem were recaptured at a higher rate.
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4.1.4.2.3. Equal Probability of Capture by Size
Since no salmon were sampled for lengths on the spawning grounds above the Middle River tag
site in 2014, size selectivity at the Middle River fishwheels could not be directly tested. Some
comparisons were made using KS tests to provide insight into the potential for size-selective
sampling. For each species, cumulative length-frequency distributions were compared for: 1)
fish captured at each of the Middle River fishwheels; and 2) fish captured at the Middle River
fishwheels and those that were radio-tagged. For the first set of comparisons, the null hypothesis
was that fish of different length were captured with equal probability, regardless of capture
location. A significant test result would indicate that the fishwheels did not capture fish of
different length equally. For the second set of comparisons, the null hypothesis was that fish had
an equal probability of being selected for tagging from those captured, regardless of length. A
significant test result would indicate that fish of different length were not selected equally for
tagging.
4.1.5. Examining Handling-Induced Changes in Behavior
As stated in RSP Section 9.7.4.1.6, an assumption of this study was that the behavior of radio-
tagged fish was not affected by the capture and handling process or by the presence of a radio tag
thereafter. The study design allowed for some fish dropping back and not resuming their
upstream migration, and these radio-tagged fish were removed from the experiment and
subsequent analyses. For the remaining fish, it was assumed that capture and tagging did not
affect final spawning destinations or migration behaviors, once they had recovered from the
tagging event and resumed migration. Four analyses were proposed in the RSP that would
provide insight into the validity of that assumption. First, comparisons of travel times between
recently-tagged and distantly-tagged fish could reveal handling effects if the recently-tagged fish
moved more slowly through a common river reach. Second, performance comparisons could
reveal handling effects if fish that were subjected to higher fishwheel holding densities (or longer
holding times) performed worse than fish with lower-density (or shorter-duration) holding
experiences. Third, examination of mark rates at spawning locations could provide an indication
of possible handling-induced changes in behavior. Finally, comparisons of post-release
migratory behavior between once-handled (fish that were never recaptured) and multiple-handled
(fish that were recaptured in the fishwheels post-release) could provide data on the effects of the
fish capture process, including any potential cumulative handling effects.
In 2014, handling-induced changes in behavior were evaluated using the first and fourth
proposed methods. In 2014, holding times and densities were always low, thus it was not
possible, nor necessary, to test whether longer times or higher densities impacted fish behavior or
survival (i.e., it was not possible to perform the second proposed test). Also, since the Indian
River weir was rendered inoperable in 2014, it was not feasible to make comparisons of mark
rates, hence the third proposed test could not be performed. For Middle River fishwheels,
potential handling effects were evaluated based on the post-release migratory behavior of
recovered vs. recently-handled fish (first proposed test), and of once-handled vs. multiple-
handled fish (fourth proposed test).
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For the Yentna River mark-recapture experiment (Table B-5), the number of dart-tagged
Chinook Salmon was deprecated based on an estimate of the proportion of radio-tagged fish not
migrating upstream.
4.1.6. Variances
RSP Section 9.7.4.1.1 stated that fishwheels would be used to capture adult salmon for tagging in
the Middle River. ISR Part C Section 7.1.2.1.2 indicated that the study team would modify the
Study Plan to add beach seining as an alternative method for sampling in September. Instead, set
gillnets were used to capture Coho Salmon in September 2014. As described in Section 4.1.1.3,
beach seine sites with suitable water depth and velocity, and in areas where fish were migrating
(and not holding), were limited in the vicinity of Curry in 2014. Gillnets proved to be an
effective alternative capture method. Relative to using fishwheels, this variance increased the
study team’s ability to achieve Objective 1.
As an alternative to stream counts and carcass surveys to obtain mark rates and length samples,
the study team implemented a variance to the Study Plan in 2013 (ISR Part A Section 4.1.8.3)
and operated a picket weir on the lower Indian River approximately 1.6 river miles from the
confluence with the Susitna River. This variance was carried over and conducted in 2014.
RSP Section 9.7.4.1.3 indicated that a portion of Chinook, Chum, and Sockeye salmon captured
in the Middle River (in excess of those required for radio-tagging) would be spaghetti-tagged to
augment the ability to test assumptions about the representativeness of fish captured in the
fishwheels. As described in Section 4.1.4.2, once the Indian River weir was rendered inoperable
in 2014, the study team recognized that there would be limited opportunity to sample fish on the
spawning grounds, so no spaghetti tags were applied at the Middle River fishwheels. This was a
variance to the Study Plan that reduced the likelihood of being able to test whether fish were
equally vulnerable to being captured and tagged over time. In lieu of this variance, the study
team used fixed-site sonar at Site 1, bank of capture comparisons, and various length-frequency
comparisons to provide insights into capture probabilities at the Middle River tag site (as
described in Section 4.1.4.2).
In addition to the variances described above, the study team also implemented several
modifications to the Study Plan methods in 2014, as proposed in ISR Section 7.1.2. RSP Section
9.7.4.1 indicated that 700 Chinook Salmon would be radio-tagged in the Yentna River in 2014.
As proposed in ISR Section 7.1.2.1.1, the study team modified the Study Plan such that all
Chinook Salmon captured at the Yentna River tag site in 2014 were marked with uniquely
numbered dart tags, of which up to 300 fish were also to receive radio tags. This modification to
the tagging strategy in the Yentna River better supported the study team’s objective (Objective 8)
to estimate Chinook Salmon escapement to the entire Susitna River (see Section 4.8.1 for more
detail).
RSP Section 9.7.4.1.1 indicated that at least one fishwheel would be operated in Devils Canyon
below the impediments from late June through late July to explore whether the sample size of
radio-tagged Chinook Salmon moving into and above the impediments could be increased.
However, as described in ISR Section 7.1.2.1.2, it was not feasible to operate a fishwheel in
Devils Canyon for a variety of reasons (e.g., uncertainty with respect to catch rates at an
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unproven site, logistical challenges, and cost). No fishwheels were operated in Devils Canyon in
2013 or 2014. The study team implemented two additional variances to the Study Plan in 2014
to compensate for the lack of a Devils Canyon fishwheel: three fishwheels were operated in the
vicinity of Curry (RSP Section 9.7.4.1.1 indicated two fishwheels would be used), and the
number of radio tags allocated to Chinook Salmon was increased to 650 (RSP Section 9.7.4.1
indicated that 400 radio tags would be used). These variances were first implemented in 2013
(ISR Section 4.1.8.1; the radio tag goal for Chinook Salmon in 2013 was increased from 400 to
560). All three of these variances were proposed modifications to the Study Plan described in
ISR Part C Section 7.1.2.1.2 that increased AEA’s ability to achieve Objective 1.
In 2014, the study team implemented a variance to the Study Plan to provide for a total of 650
Chinook Salmon to be radio-tagged in the Middle River in 2014, with a goal of tagging 550 large
(METF ≥ 50 cm [19.7 in]) and up to 100 small (METF < 50 cm [19.7 in]) Chinook Salmon.
RSP Section 9.7.4.1.2 stated that 400 large Chinook Salmon would be radio-tagged in the Middle
River. In 2013, modifications to increase the tag goal (from 400 to 560 large Chinook Salmon)
and radio tag small Chinook Salmon were both implemented as variances (ISR Sections 4.1.8.1
and 4.1.8.2). As indicated in RSP Section 4.1.8.2, small Chinook Salmon comprised a
substantial portion of the catch in 2013, so it was deemed worthwhile to apply some tags to this
segment of the population to help characterize spawning locations. The study team proposed this
change as a modification to the Study Plan in ISR Part C Section 7.1.2.1.2. In both years, this
variance increased AEA’s ability to achieve Objectives 1, 2, and 3.
RSP Section 9.7.4.1.6 indicated that AEA would assess the effects of holding time and density
on the behavior of tagged fish. Due to stipulations in the Fish Resource Permit, all fish were
tagged soon after capture in 2014, thereby reducing holding times and densities to levels that
made comparisons of post-release survival and migration behavior unnecessary. This variance
was implemented in 2013 (ISR Section 4.1.8.3) and 2014 and it was proposed as a Study Plan
modification in ISR Part C Section 7.1.2.1.2. This variance did not affect achieving study
Objective 1.
RSP Section 9.7.4.1.7 indicated that contingency table analyses would be used to compare the
sex and age composition of radio-tagged fish. However, as stated in ISR Section 4.1.8.3, early in
the 2013 field season it became clear that correctly identifying fish sex based on external
morphological characteristics would be difficult at the Middle River fishwheels. Fish sex was
therefore not recorded in 2014. Scales were also not collected from salmon in 2014, in light of
the fact that size selectivity would be tested, fish were randomly selected for tagging, and the
study team minimized the amount of handling time for each fish. Contingency table analyses
were not conducted in 2014, which was a Study Plan variance that was proposed as a
modification in ISR Part C Section 7.1.2.1.2. The same variance was implemented in 2013 (ISR
Section 4.1.8.3). Since size selectivity could not be directly tested in 2014 due to the Indian
River weir being rendered inoperable, this variance decreased the ability to assess capture
probabilities at the Middle River fishwheels (Objective 1). To meet this Objective without
recapture data, the study team relied on length-frequency comparisons and results from previous
study years to provide insights into capture probabilities based on size at the Middle River tag
site.
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4.2. Objective 2: Determine the migration behavior and spawning
locations of radio-tagged fish in the Lower, Middle, and Upper
Susitna River
In 2014, AEA implemented the methods with respect to Objective 2 as described in the Study
Plan, with the exception of modifications described in Section 7.1.2 of the ISR and variances
described below (Section 4.2.4). Tasks to address Objective 2 were listed in RSP Section
9.7.4.2.
Three groups of radio-tagged fish were tracked: 1) adult Chinook, Coho, Chum, Pink, and
Sockeye salmon radio-tagged at the Middle River fishwheels (PRM 123–126); 2) Chinook,
Coho, and Pink salmon radio-tagged in the Lower River (PRM 33–34); and 3) Chinook Salmon
radio-tagged in the lower Yentna River (Figure 3-1). The three study components and data
analyses were tightly coordinated. All mobile and fixed-station receiver data were analyzed
together, and analysis products were characterized in a consistent manner.
The primary function of the telemetry component was to track these tagged fish spatially and
temporally with a combination of fixed and mobile receivers. Time/date stamped, coded radio
signals from tags implanted in fish were recorded by fixed-station or mobile positioning. All
telemetry gear (tags and receivers) was manufactured by ATS.
The types of behavior characterized included the following:
Arrival and departure timing at specific locations/positions
Direction of travel
Residence time at specific locations/positions
Travel time between locations/positions
Identification of migratory, holding, and spawning time and locations/positions
Movement patterns in and between habitats in relation to water conditions (e.g.,
discharge, temperature, and turbidity).
These data, in conjunction with habitat descriptions, allowed characterization of migratory
behavior and final destinations for salmon in mainstem habitats (main channel, slough, side
channel, and tributary mouths) and tributaries. Spawning or final locations of tagged fish were
used to determine the number and proportion of the tagged fish of each species using mainstem
habitats.
4.2.1. Fixed-station Monitoring
Stand-alone operating telemetry arrays were deployed at strategic locations in the Lower,
Middle, and Upper River to provide migration checkpoints, develop spawning ground
inventories, and monitor the destinations of individual tagged fish. In total, 20 fixed-station
receiver sites were operated in 2014 (Figure 3-1; Table C-1). This was one more fixed-station
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monitoring site from what was proposed in the RSP Section 9.7.4.2.1 and three less sites than
were implemented in 2013 (ISR Part A, Section 4.2.1). The receiver site proposed for the Indian
River weir was not operated in 2014 since the weir was rendered inoperable by a flood.
Ten fixed-station receiver sites were operated in the Lower River in 2013 and 2014 and were
largely chosen to represent significant tributaries that were known to contain Chinook Salmon.
Eight sites were located in tributaries (Lower Yentna, Skwentna, Upper Yentna, Talkeetna,
Chulitna, Deshka Weir, Montana Creek Weir, and Middle Fork Chulitna Weir) and two sites
were located on the mainstem Susitna River (Deshka Mouth [PRM 40] and Sunshine [PRM 83]).
All Lower River sites were equipped with two antennas to detect both upstream and downstream
passage (Table C-1). In 2014, the first Lower River site began operating the week of May 19
and all sites were demobilized by the week of September 22 (Table C-2).
Middle and Upper River sites were chosen to both provide geographic separation of the Middle
River area to describe migration and spawning behaviors, and monitor at the appropriate
resolution to quantify passage through Devils Canyon and the Upper River. Five fixed-station
receiver sites were operated in the Middle River within or below Devils Canyon, all of which
were located on the mainstem Susitna River (Lane Creek area [PRM 116.7], Middle River
Gateway [PRM 130.1], Indian River confluence [PRM 142.0], Cheechako Creek [PRM 157.3],
and Chinook Creek [PRM 160.4]). One fixed-station receiver site was operated on the mainstem
Susitna River in the Middle River above Devils Canyon (Devils Island [PRM 166.9]). All
Middle River sites were equipped with at least two antennas to detect upstream and downstream
passage (Table C-1). One antenna at the Indian River site was oriented directly up the tributary
to detect fish moving into the lower Indian River. In 2014, the first Middle River site began
operating the week of April 28 and all sites were demobilized by the week of October 27 (Table
C-3).
Four fixed-station receiver sites were operated in the Upper River, all of which were located in
the mainstem Susitna River (Watana Dam site [PRM 187], Watana Creek [PRM 197], Kosina
Creek [PRM 209], and Oshetna River [PRM235]). Each of these sites was equipped with two
antennas to detect upstream and downstream passage. The Watana Creek, Kosina Creek, and
Oshetna River sites were also equipped with a third antenna to detect fish passage into the
respective tributaries (Table C-1). The first Upper River site began operating the week of April
28 and all sites were demobilized by the week of October 13 (Table C-3). All receivers scanned
Chinook Salmon tag frequencies to begin the season. Additional frequencies were scanned as
other species were captured and tagged in the fishwheels.
Fixed-station receivers were manually downloaded at least once a week. All fixed stations were
designed to cover the entire channel width of the respective tributary or mainstem Susitna River.
The Lane Creek and Watana Dam sites were operated with two receivers (all other sites had just
one receiver). Lane Creek operated with one receiver scanning the tag frequencies deployed in
the Lower River and the other receiver scanning the tag frequencies deployed in the Middle
River (Table C-1). The Watana Dam site fixed-station operated with one receiver scanning all
salmon tag frequencies and a second receiver, operating as a backup, scanning all Chinook
Salmon frequencies. Additional methods pertaining to the set-up and operation of fixed-station
receiver sites were provided in RSP Section 9.7.4.2.1.
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4.2.2. Aerial Telemetry Surveys
In 2014, aerial telemetry surveys were conducted in the Lower River by fixed-wing aircraft and
helicopter, and in the Middle and Upper River by helicopter. Survey coverage included the
mainstem Susitna River from the mouth (PRM 0) upstream to areas above the Clearwater Creek
confluence (PRM 266.6) in the Upper River, as well as most major tributaries. Surveys targeting
adult salmon began on June 11 and continued through October 30 (Table C-4). Surveys were
scheduled to cover each section of the river (Lower, Middle, and Upper rivers) at least once
every five days for helicopter surveys and every 14 days for fixed-wing surveys. Survey timing
was adjusted depending on the observed fishwheel catches in the Lower and Middle rivers.
Helicopter surveys were conducted at lower elevations (100–200 m [328–656 ft]) and at slower
speeds than possible with fixed-wing aircraft, and therefore allowed more time for signal
acquisition, higher spatial resolution, and fish habitat observations. In general, the spatial
resolution of helicopter surveys was approximately 300 m (984 ft). Higher precision was
achievable in reaches where conditions were most favorable and observers could determine
whether the fish was in off-channel or mainstem habitat. Fixed-wing aerial telemetry surveys
provided fish locations to the nearest river mile and helped to characterize the destinations of
radio-tagged fish. Although the fixed-wing surveys provided less precise spatial resolution of
fish locations (and habitat use) than the helicopter surveys, they more effectively covered the
large lineal distances of the Susitna River tributaries where higher spatial resolution was not
required.
The mainstem aerial telemetry surveys covered over 265 river miles, and multiples of that total
when side channels and braids of the Lower River were included. To allocate survey effort
efficiently and to the highest priority needs, resolution was a function of fish behavior. The
highest priority and highest resolution needs were for fish that appeared to be holding or
spawning. For migrating fish, resolution to the nearest 500 m (1,640 ft) of river was generally
sufficient. Frequent surveys enabled high-resolution and time-intensive tracking effort to
identify the exact locations of spawning and holding fish. During salmon spawning periods, the
crew used a GPS with a Geographic Information System (GIS) based map containing the
locations of each fish during the previous survey. Locations where fish were repeatedly
observed were further investigated to ensure an accurate position for the fish and look for visual
evidence of spawning activity.
Geographic coordinates were recorded for each signal detected using an integrated
communication link between the telemetry receiver and a GPS unit. The position of the fish was
determined by the position of the aircraft at the time of the highest signal power. Range testing
of the mobile aerial setup was conducted in the Middle River to confirm detection ranges for
typical flying heights, and receiver gains, as well as to work with the helicopter pilot to refine the
methods for achieving highest spatial resolution.
Tag identification and GPS coordinates were archived and systematically processed after each
survey. A data-handling script was used to extract unique tag records with the highest power
level from the receiver files generated during the survey. These records were imported into a
custom database software application (Telemetry Manager) and incorporated into a GIS-based
mapping database. Geographically and temporally stratified data for radio-tagged fish were
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provided to the habitat sampling team (Study 9.9) and Instream Flow Study (Study 8.5) to inform
their field sampling efforts.
4.2.2.1. Lower River Surveys
Aerial telemetry surveys of the Lower River and tributaries covered areas from the mouth of the
Susitna River to the confluence of the Chulitna River (PRM 102.4). From June 12 to October
30, 63 fixed-wing and helicopter surveys were conducted in the Lower River (Table C-4).
Fixed-wing telemetry surveys were conducted in the Lower River and tributaries from June 24 to
September 23. Tag frequencies for Chinook Salmon (tags released in the Lower and Middle
rivers) were scanned during Lower River fixed-wing surveys from June 24 to August 11, after
which there was little value in collecting additional detections from the inactive tags. Tag
frequencies for Coho Salmon were scanned through September 23 (except for August 8 and
August 11 in the Yentna River when no tag frequencies for Middle River Coho Salmon were
scanned). Tag frequencies for Chum, Pink, and Sockeye salmon released in the Middle River, as
well as Pink Salmon released in the Lower River, were not scanned during fixed-wing surveys in
the Lower River. These fish were tracked during helicopter surveys (Table C-4).
Helicopter telemetry surveys were conducted in the Lower River and tributaries from June 12 to
October 30. The mainstem Susitna River was highly braided in this section with side channels
and sloughs, so complete coverage with the helicopter required approximately one day of effort.
Lower River tributaries were typically surveyed for approximately three miles. More extensive
surveys were conducted in tributaries during the fall to locate pink salmon tags in tributaries.
Tag frequencies for Chinook Salmon were scanned during Lower River helicopter surveys from
June 12 to August 31. Tag frequencies were scanned through September 30 for Chum and Pink
salmon, October 16 for Sockeye Salmon, and October 30 for Coho Salmon.
4.2.2.2. Middle River Surveys
Helicopter telemetry surveys of the Middle River and tributaries were conducted from June 11 to
October 28 and covered mainstem areas from the confluence of the Chulitna River (PRM 102.4)
through Devils Canyon to the proposed Watana Dam site (PRM 187.1). The reach from the
Chulitna to Portage Creek required approximately one day to complete and was conducted on 63
days (Table C-4). The river between Devils Island (PRM 166.9) and the proposed Watana Dam
site was usually flown on the same day as the surveys of the Upper River, but also on additional
days to download fixed stations (a total of 49 days). Once adult salmon were observed entering
Devils Canyon, the Susitna River and its tributaries from Portage Creek to Devils Island were
surveyed every 1–2 days (June 28 to August 6) to ensure information on passage timing, hold
duration, and potential spawning destinations. These frequent flights continued until upstream
movement of fish in Devils Canyon had stopped. During the peak Chum and Sockeye salmon
migration and spawning periods in the Middle River, the river section from the mouth of the
Chulitna River to Devils Island was surveyed every third day (August 9 to October 28) to
monitor the movements of salmon into spawning and holding locations. The interval between
flights, shorter than the proposed 5-day interval (RSP Section 9.7.4.2.2), was proposed as a
Study Plan modification that was detailed in ISR Part C Section 7.1.2.2 and implemented in
2014. For both Middle and Upper River helicopter surveys, tag frequencies were scanned
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through August 31 for Chinook Salmon, September 30 for Chum and Pink salmon, October 28
for Sockeye Salmon, and October 30 for Coho Salmon.
The increased frequency of aerial telemetry surveys conducted on the Middle River in 2014,
from Whiskers to Portage creeks, provided multiple detections for most of the radio-tagged fish
in this portion of the river. These detections before, during, and after the spawning period
allowed for the identification of fish that were likely migrating and/or spawning in mainstem
habitats. In 2014, there was a high degree of consistency between the potential spawning sites
identified for radio-tagged Sockeye Salmon, and to a lesser degree Chum Salmon, and the
visually confirmed redd sites for these species. This consistency provided further support as to
the usefulness of using radio telemetry to detect spawning locations in mainstem habitats of the
Susitna River.
4.2.2.3. Upper River Surveys
Helicopter telemetry surveys of the Upper River and tributaries were conducted from June 11 to
October 14 and covered the mainstem areas from the proposed Watana Dam site (PRM 187.1) to
upstream of the Clearwater Creek confluence (PRM 266.6). This reach included approximately
48 relatively confined river miles. This survey required approximately one day to complete and
was conducted on 23 days (Table C-4). It took less time to complete this survey when done in
conjunction with Middle River surveys because less conveyance time was required. Helicopter
telemetry surveys of the Upper River generally were triggered by the detection of fish moving
above the Devil Creek fixed station. When tags were detected above Devils Canyon, the aerial
telemetry survey continued upstream and into the tributaries until all of the tag(s) that had passed
were located. Surveys for Chinook Salmon were conducted until the end of August.
4.2.3. Telemetry Data Analysis
4.2.3.1. Data Filtering
As in 2012 and 2013, the following criteria were set for tag detection records to be considered
valid in 2014:
1) for fixed-station receiver data, there must have been at least five detections recorded on
directional antennas per minute (single records, or records separated by more than one
minute were rejected; all detections on the pooled master antennas were ignored; the
criterion at noisy receivers was 7 signals in one minute (slight noise) or 100 hits in 60
minutes (severe noise);
2) for mobile data, single detections were allowed but were closely scrutinized on a case-by-
case basis; and
3) any detections requiring unrealistic travel times were removed.
Additional details regarding telemetry data processing were provided in Section 4.2.5.4 of the
2012 study report (AEA 2013a).
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4.2.3.2. Classifying Spawning Destinations and Holding Locations
The detection history of each individual radio-tagged salmon was examined in order to classify
the fish to one of two types of “spawning/holding destination” (Tributary vs. Mainstem
Destination) based on temporal patterns in their detection positions. Spawning and holding
locations for salmon are considered together from a biological and analytical perspective for the
study. The study team used detection histories, instead of final tag locations, to assign a
destination because salmon can drift downstream after spawning or death, obscuring the true
destination and distribution of the fish. The algorithms that were used to define potential fish
spawning behavior were developed based on assumptions about fish behavior and physiology.
The specific steps used to classify each fish are described below.
Since these classifications were based on telemetry detections, they cannot be considered as
‘confirmation of spawning’, hence terms such as ‘likely’ and ‘possible’ were used in this report
(see below). Confirmation of spawning/holding required further research, including the use of
sonar for Chinook Salmon in turbid water (Objective 4), as well as aerial, boat-based, or visual
surveys for all salmon species. As much as possible, the analyses described below were
performed in season, and provided a list of potential locations for field crews to visit for
confirmation of spawning activity.
Not all fish could be assigned to one of the two types of spawning/holding destination. For
example, several fish were excluded from analyses because they exhibited unexpected behaviors
that suggested potential handling-related effects. The detections of these fish indicated that: 1)
the fish never left the release area, 2) the tag was never detected, or 3) the fish moved only in a
downstream direction. Other tagged fish had tracking histories that suggested they never arrived
at their spawning destination and thus, these fish were assigned to a classification called “Other
Mainstem.” The Other Mainstem category comprised all fish that were included in the analyses
but which could not be assigned to one of the two destination categories.
Fish assigned to the Tributary Destination category included all salmon that moved into a
tributary river or stream flowing into the Susitna River, presumably for spawning, regardless of
whether they subsequently returned to the mainstem Susitna River. The tributary into which the
fish entered was recorded as its spawning “stock.” Any fish that entered one tributary, exited,
and subsequently entered another tributary was given a stock assignment based on the tributary
where more time was spent. Any fish that spent less than 6 days in a tributary was examined as
described below, in order to assess it as a possible mainstem spawner. The study was not
designed to identify exact spawning positions within the tributaries, so spawning locations in
tributaries were not described.
After classifying the Tributary Destination fish, all remaining fish were classified on a fish-by-
fish basis either into the Mainstem Destination or Other Mainstem category. Classifications
were assigned after displaying a fish's complete detection history over ortho-rectified aerial
imagery, and examining each detection in succession. Before proceeding with classification,
several detections were eliminated from consideration. First, movements were ignored after the
tag entered mortality mode (unless the movements indicated the tag’s sensor malfunctioned).
Second, downstream movements following the most upstream location were typically ignored as
the fish may have already been dead or moribund, unless the fish showed subsequent upstream
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movements. Third, all fish that died within two weeks of tagging were classified immediately
into the Other Mainstem category. The remaining data were examined, looking for any
geographically aggregated cluster of detections which might indicate that the fish should
potentially be included in the Mainstem Destination category. Clusters in which the last live
detection was earlier than the published species-specific spawn-timing window (Schmidt and
Bingham 1983, Barrett et al. 1985a,b, Jennings 1985, Thompson et al. 1986) were ignored as
they were considered to be aberrant data points possibly resulting from bear-kills, angler-catches,
handling related-mortalities, or other causes of mortality, and they were unlikely to have been at
their spawning destination at the time of death (n = 32 combined for 2012, 2013, 2014). Each
remaining cluster was scrutinized before placing it into one of two ‘relative spawning
probability’ groups:
Clusters were classified as “likely” spawning/holding locations based on the number of
repeat detections and density of unique detections in the same area. A likely spawning
cluster consisted of multiple unique detections in relatively close proximity to one
another. The number of unique detections was variable, but could be as few as three if
they were grouped tightly enough together; the distance between unique detections also
varied, but was generally within a few hundred meters (< 1,000 ft). In these cases, the
fish was assigned to the Mainstem Destination category.
Clusters were classified as “possible” spawning/holding locations if the cluster was made
up of fewer unique detections (sometimes only two); or, when more unique detections
were present, but the locations were loosely aggregated. Also included in this group were
clusters located in areas where fish may have been holding (rather than spawning, e.g.,
tributary mouths). These fish were also assigned to the Mainstem Destination category.
When tags were physically recovered in a known mainstem spawning area (based on data
for the 1980s studies), the recovery location was listed as a “likely” Mainstem
Destination, regardless of the nature of the detection cluster.
Salmon in the Mainstem Destination category had a cluster of detections in the potential
spawning/holding area, and a single representative location was selected from within the cluster.
The single selected point was either the last live detection, the detection with the most powerful
signal strength, or a detection that appeared to represent the center of mass of the cluster. For
each fish, the position of its potential spawning/holding location was plotted on ortho-rectified
aerial imagery in order to categorize the habitat as either Side Channel/Slough, Tributary Mouth,
or Mainstem Proper, based on the position of the potential spawning location. All tag locations
classified as spawning locations (“likely” and “possible”) following radio-telemetry analysis
were further investigated to confirm spawning and holding activity. This included the use of
sonar for Chinook Salmon in turbid water, as well as aerial, boat-based, and visual surveys for all
salmon species.
The timing of spawning events could not be confirmed using radio-telemetry. However, the
tracking data were used to estimate approximate spawn-timing windows. For each fish assigned
to Mainstem Destinations, their single representative location had an associated date. Taken
together, the dates corresponding to all the representative locations had a distribution, whose 10th
and 90th percentiles were used to describe mainstem spawn timing. For Tributary Destinations,
the dates when fish were detected within the assigned spawning tributary were used to generate a
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spawn timing distribution. Detections in mortality mode were excluded, and so were fish that
went to minor tributaries (i.e., those for which less than 10 percent of the fish in that river section
had destinations). Tributary spawn timing was described in terms of the 10th and 90th percentiles
of the dates in this distribution.
4.2.4. Variances
RSP Section 9.7.4.2.1 listed ten fixed-station receiver sites to be used in the Middle and Upper
rivers. ISR Part C Section 7.1.2.2 described a Study Plan modification to include eleven fixed-
station receiver sites in the Middle and Upper rivers in 2014, of which seven sites were listed in
RSP Section 9.7.4.2.1 (Lane Creek, Gateway, Indian River confluence, Cheechako Creek,
Chinook Creek, Devil Creek area, and Kosina Creek) and four sites were not (Indian River weir,
Watana Dam sonar site, Watana Creek, and Oshetna River). However, only ten sites were used
in 2014 (see Section 4.2.1). One of the eleven sites proposed for 2014 was planned for the
Indian River weir in order to detect radio-tagged salmon passing the weir. Since the weir was
rendered inoperable by a flood on June 26 prior to the start of the Chinook Salmon migration
into the Indian River, this fixed-station receiver site was not operated in 2014. This variance did
not affect AEA’s ability to achieve Objective 3.
RSP Section 9.7.4.2.2 indicated that aerial telemetry surveys would be scheduled at five-day
intervals with the intent to ensure a maximum of seven days between surveys with weather
contingencies. In 2014, the study team implemented a variance to the Study Plan and increased
the frequency of surveys in the Middle River to every 1-2 days between Portage Creek and
Devils Island from June 28 to August 6, and every third day between the Chulitna River and
Devils Island from August 9 to October 28 (as described in Section 4.2.2.2). This change was a
proposed Study Plan modification described in ISR Part C Section 7.1.2.2. This variance
improved the resolution of the geographic positions of tagged fish in the Middle River (below,
within, and above Devils Canyon) and helped AEA achieve study Objectives 1, 2, and 3.
4.3. Objective 3: Characterize adult salmon migration behavior and
timing within and above Devils Canyon
In 2014, AEA implemented the methods with respect to Objective 3 as described in the Study
Plan, with the exception of modifications described in ISR Part C Section 7.1.2 and variances
described below (Section 4.3.5). Tasks to address Objective 3 were listed in RSP Section
9.7.4.3.
4.3.1. Fixed-station Monitoring
A combination of aerial telemetry surveys and fixed stations below, within, and above Devils
Canyon was used to determine the migration timing and behavior of radio-tagged salmon that
passed into the Upper River (Figure 3-1). As described in Section 4.2.1, four fixed-station
receiver sites were deployed in the Upper River (Watana Dam site, Watana Creek, Kosina Creek,
and Oshetna River) at locations where they had the highest probability of detecting radio-tagged
salmon. Fixed stations deployed at the confluences with Kosina Creek and the Oshetna River
were used to guide aerial survey efforts needed to identify spawning areas in the Upper River.
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4.3.2. Aerial Telemetry Surveys
Aerial telemetry surveys were conducted via helicopter within and above Devils Canyon from
June 11 to October 28. These surveys provided location data for radio-tagged fish in areas that
were not directly monitored by fixed-station receiver sites (i.e., in the mainstem between fixed-
station receiver sites, and within tributaries). These detections assisted with the successful
tracking of fish movements within and above Devils Canyon, providing day-to-day locations,
passage timing, and hold durations. Surveys were typically flown until all radio-tagged fish
known to have passed the Devil Creek fixed station had been detected. Additional details on the
range of survey dates, survey frequency, and survey coverage were provided in Section 4.2.2,
and details regarding the 2014 Study Plan variance to increase the frequency of aerial telemetry
surveys were provided in Section 4.2.4. Aerial telemetry data were critical for the identification
of potential spawning behavior and detecting potential spawning and holding locations. The goal
of 300 m (984 ft) accuracy of geographic position when locating tagged fish, including spawning
and holding fish (RSP Section 9.7.4.2.2), was achieved by the combined effect of airspeed, flight
path, antenna direction, and receiver gain control. In addition, the aerial detections contributed
to the estimation of detection efficiencies for each fixed station. The timing and proportion of all
tagged salmon that passed Devils Canyon was calculated and compared with the remaining
tagged population, and their final spawning locations were identified. The total number of radio-
tagged fish that were detected at or above Gateway Station (PRM 130.1) was used to estimate
the proportion of fish that migrated through the Middle River and above Devils Canyon.
4.3.3. Aerial Spawner Surveys
Aerial spawner surveys (by visual observation via low-flying helicopter) to determine the
distribution and relative abundance of adult Chinook Salmon were conducted in Susitna River
tributaries within and above Devils Canyon, upstream to and including the Oshetna River. These
surveys helped to identify potential spawning locations for Chinook Salmon that may not be
represented by the radio-tagged segment of the population. A total of seven aerial spawner
survey events were conducted at approximate weekly intervals from July 14 through August 19,
2014 (Table 4.3-1). The survey extent covered the same major tributaries and clear-water areas
of the Susitna River as during 2012 and 2013 (Table 4.3-1; Figure 4.3-1). From Cheechako
Creek to the Oshetna River, a total of 18 streams were surveyed; 12 tributaries to the Susitna
River and six secondary tributaries. All streams were surveyed from their confluence up to
3,000 ft in elevation, to a predetermined barrier to anadromous fish passage, or to the stream’s
headwater origin, whichever came first.
Additionally, two lakes in the Tsisi Creek drainage were surveyed in 2014 specifically to look
for spawning Sockeye Salmon. Based on anecdotal information from a pilot that flies planes
frequently in the Upper River, Alaska Department of Fish and Game (ADF&G) staff requested
AEA extend the spawner surveys to include these locations and evaluate the claim that sockeye
salmon may to be spawning in these lakes. Five surveys of the Tsisi lakes were conducted from
late July to mid-August 2014 (Table 4.3-1).
Survey confidence was estimated independently for each stream during each survey event by
ranking three variables that may have affected the observers’ ability to see fish: 1) sun glare on
the water; 2) clarity of the water (i.e., turbidity, not white water created by rapids); and 3)
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overhanging vegetation. Variables were ranked from zero to four, where four indicated optimal
survey conditions and zero indicated poor survey conditions.
Quality-control measures included employing two observers on all surveys, with one observer
remaining consistent throughout the study. Observers communicated fish sightings to each other
and when necessary, the flight was slowed or halted until both observers had confirmed the
number of fish present. The helicopter pilot was consistent for survey events two through five.
Observer efficiency was evaluated with a one-time paired independent aerial spawner survey
during the peak of Chinook Salmon spawning in Indian River.
4.3.4. Using Sonar to Enumerate Salmon at the Proposed Dam Site
As stated in Section 1 of the FERC SPD, it was recommended that AEA evaluate the feasibility
of putting in a weir or operating a sonar counting station at or near the dam site in the next year
of study to count fish migrating through Devils Canyon (FERC 2013a). Prior to the 2013 field
season, operation of a weir near the dam site was determined to be not feasible due to the
physical limitations of a weir withstanding the normal range of discharges for the mainstem
Susitna River. In 2013, AEA assessed the feasibility of placing a sonar counting station at or
near the dam site (see ISR Appendix G). Results from 2013 field activities showed that it was
likely feasible to count salmon-sized fish and corroborate counts with radio-telemetry.
In 2014, AEA used sonar (ARIS) to count the number of salmon-sized fish passing the proposed
Watana Dam site (PRM 187.1) from July 6 to August 22. Methods describing this study
component were provided in the September 2014 Implementation and Preliminary Results
Technical Memorandum (AEA 2014a) and Appendix G. The primary objectives for this study
component were to estimate the number of net upstream-moving Chinook Salmon that passed
through the sonar beams, and to describe temporal (daily and hourly) and spatial (range of
passage) patterns of Chinook Salmon observations. AEA also implemented a variance to the
Study Plan in 2014 and collected bathymetry and water-velocity profiles (acoustic Doppler
current profiler, ADCP) at the monitoring sites to corroborate assumptions regarding the fish
migration corridor at this site.
4.3.5. Variances
RSP Section 9.7.4.2.2 indicated that aerial telemetry surveys would be scheduled at five -day
intervals. As proposed in ISR Section 7.1.2.2, AEA modified the Study Plan by increasing the
frequency of aerial telemetry surveys from the mouth of the Chulitna River to Devils Island to
three-day intervals in 2014. Increasing the frequency of aerial telemetry surveys was also
implemented as a variance in 2013 (ISR Section 4.3.5). This modification enhanced AEA’s
ability to characterize migration behavior and achieve study Objective 3.
To support further assessment of the fish migration corridor at the Watana Dam sonar site, AEA
conducted seven ADCP transects in 2014. To supplement the velocity transects, bathymetric
data were also collected. These two tasks were variances to the Study Plan that increased the
likelihood of AEA achieving study Objective 3.
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4.4. Objective 4: Use available technology to document salmon
spawning locations in turbid water
In 2014, AEA implemented the methods with respect to Objective 4 as described in the Study
Plan, with the exception of modifications described in Section 7 of the ISR and variances
described below (Section 4.4.3).
In late July 2014, AEA used a Dual Frequency Identification Sonar (DIDSON) to characterize
suspected Chinook Salmon spawning in turbid water of mainstem habitat of the Middle River.
This was a variance to the Study Plan since RSP Section 9.7.4.4 indicated that sonar would be
used to characterize any suspected salmon spawning in turbid water. As described in ISR Part A
Section 6.5, sonar was not able to differentiate between Chum, Coho, Pink, and Sockeye salmon
due to overlap in their run timing and body size. This variance was proposed as a Study Plan
modification in ISR Part C Section 7.1.2.4. The use of a DIDSON in 2014 followed the RSP
(Section 9.7.4.4), but varied from what was used in 2013 (ARIS; see ISR Part C Section 7.1.2.4),
yet both tools have similar capabilities. Potential Chinook Salmon spawning locations were
identified from historic spawning locations reported in the 1980s, and from 2012, 2013, and
2014 detections of radio-tagged fish. Sites with physical features indicative of Chinook Salmon
spawning habitat were also sampled on an opportunistic basis. Potential spawning sites that
could not be accessed by boat, or sites with physical characteristics not suitable for sonar
sampling (e.g., low water or entrained air), were not sampled.
Additional site-specific information was collected and subsequently relayed to the Fish and
Aquatics Instream Flow Study (Study 8.5) team.
4.4.1. Sonar Equipment and Methods
The sonar system consisted of a Sound Metrics Corporation (SMC) DIDSON, SMCX2 dual-axis
rotator assembly, data transmission cable, top-side control box, laptop computer with DIDSON
data acquisition software (version 5.26.06), and portable external hard drive. The system was
deployed using a pole-mounted winch that was secured to the gunwale of a jet-drive boat. Once
the sonar was lowered to an appropriate depth (which varied depending on site-specific
conditions), the SMCX2 rotator was used to pan and tilt the sonar from the surface to search for
fish activity. The system was powered by a battery bank consisting of four, 12 -volt (V), deep-
cycle batteries. The battery bank was recharged at the end of each day with a 2,000 watt (W)
Honda EU2000i generator.
At each site, the boat was moored and the DIDSON was lowered to scan for suitable substrate
and/or the presence of Chinook Salmon. If suitable substrate was observed, a scan was
performed until fish were observed, or for a maximum of 15 minutes (if no fi sh were observed).
Once fish were observed, recording of sonar imagery was initiated. If suitable substrate was not
present or no fish were observed at the sample site, the DIDSON was retrieved and the system
was relocated to another site. Only habitats with features known to support salmonid spawning
(as defined by Groot and Margolis 1991; Quinn 2005) were surveyed. Sites were excluded if:
The location was in the thalweg of the mainstem Susitna River, with no structure
providing relief from the river flow.
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The location was an area of high velocity with no holding areas (i.e., greater than 1.5
meters per second [m/s; 4.9 feet per second (ft/s)]).
The location consisted of shallow water with high velocity.
The location was in the middle of a rapid or area with high velocity.
The location had unsuitable substrate (i.e., mud, silt).
Excessive amounts of entrained air occurred at the sample location.
Data were initially collected using 10–20 m (33–66 ft) sample windows. Typically the sonar unit
was tilted down to allow the sample beams to spread along the substrate throughout as much of
the sample range as possible. In reaches with a non-uniform slope or that had obstructions
present, the DIDSON depth and tilt angle were adjusted as necessary to maximize c overage of
the substrate.
When fish were located and spawning activity was suspected, up to 30 minutes of data were
collected. Adjustments of the pan and tilt angles were made as required to maintain visual
observation of individual fish. Due to the presence of Chum Salmon at some sites, the minimum
total length (TL) for a target to be considered a Chinook Salmon was increased to 80 cm TL
(31.4 in).
Data were collected using a frame rate of eight frames per second. Data were ported directly to
external hard drives, and backed up and archived to additional hard drives after each survey.
Locational data were collected using a hand-held GPS unit to allow for geo-referencing of
sample locations.
4.4.2. Sonar Data Analysis and Reporting
Data processing involved playing back the streaming data files using DIDSON software. Files
were reviewed to note the following for each survey:
Presence or absence of Chinook Salmon. When adult salmon-sized fish were detected,
total lengths of individual fish were estimated using the software’s sizing tool.
Presence or absence of spawning behavior activities. Behavior of individual fish was
reviewed and observations of spawning activities (redd digging or covering, redd
guarding, paired fish, aggressive territorial behaviors, egg laying, milt expulsion,
quivering) were noted.
Presence or absence of redds.
4.4.3. Variances
RSP Section 9.7.4.4 indicated that sonar would be used to characterize any suspected salmon
spawning in turbid water of the mainstem habitats of the Susitna River (as indicated by radio-
telemetry analysis). As discussed in Study 9.7 ISR Part A Section 6.5 for 2013, the use of sonar
was limited particularly in shallow water, close to the shoreline, and at sites where multiple
species of similar body lengths were present. It was confirmed that many of the shallow
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locations that were not accessible for sonar use were spawning sites for Chum and Sockeye
salmon. Thus in 2014, the study team implemented a variance to the Study Plan and used sonar
only to characterize suspected Chinook Salmon spawning. This variance was proposed as a
Study Plan modification in ISR Part C Section 7.1.2.4. Although this variance limited the ability
to document spawning locations in turbid water for Chum, Coho, Pink, and Sockeye salmon in
2014, the Objective was met by demonstrating that sonar is not an effective tool given the typical
habitat conditions where these species spawn.
4.5. Objective 5: Compare historical and current data on run timing,
distribution, relative abundance, and specific locations of
spawning and holding salmon
AEA implemented the methods with respect to Objective 5 as described in the Study Plan with
no variances. Comparisons were made between this study’s results (2012–2014) and historical
results (1981–1985) that characterized the relative abundance; locations of spawning and holding
salmon; and use of mainstem, side channel, slough, and tributary habitat types by adult salmon.
Research conducted in the early 1980s provided annual abundance estimates (1983–1985)
relevant to at least four fishwheel sites along the Susitna River. These abundance estimates were
apportioned to mainstem, sloughs, and tributaries. The 1980s studies relied heavily on visual
observations of fish and abandoned late-season redds, and therefore, may have underestimated
the use and relative importance of mainstem habitats, many of which occur in turbid water
during a substantial portion of the spawning period. Another concern was that data collected
approximately 30 years ago may not characterize the current habitat use by salmon in the
mainstem Susitna River.
This study addressed both of these concerns by deploying a similarly scaled study of the
spawning runs to the Susitna River in 2012, 2013, and 2014, and by using radio telemetry and
sonar technology not available in the 1980s. Both methods provided a more rigorous
characterization of the use of mainstem habitats than methods used in the 1980s. To the extent
spawning distribution and habitat use in the current study were similar to earlier studies, the
current study greatly increased the sample size and confidence in the conclusions from studies in
both periods.
4.5.1. Variances
No variances from the methods described in the Study Plan occurred during the 2014 study
season.
4.6. Objective 6: Generate counts of adult Chinook Salmon
spawning in the Susitna River and its tributaries
The study team implemented the methods with respect to Objective 6 as described in the Study
Plan, with the exception of modifications described in Section 7.1.2 of the ISR, and variances
described below (Section 4.6.1). In 2014, this objective was addressed by attempting to operate
a weir on the Indian River (see Section 4.1.4.2) and conducting aerial spawner surveys in the
Indian River (see Section 4.3.3). The purpose of this work was to establish survey-area mark
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rates (proportion of fish tagged in different areas) that would support inferences about the
representativeness of tagging across spawning stocks. In addition, mark rates from these areas
could be used to estimate the abundance of salmon passing the tagging sites (the weir was
rendered inoperable by a flood; the ensuing study variances are described in detail in Section
4.6.1). The aerial spawner surveys were not intended to provide a direct estimate of the total
Chinook Salmon abundance. Instead, they provided a minimum count, and then helped to
establish minimum and likely tributary-specific mark rates, as was done for Portage Creek
(2012) and the Indian River (2012 and 2013) in previous years.
Concurrent aerial telemetry surveys were conducted in the Indian River in July and August 2014
to determine the number of live radio-tagged Chinook Salmon present. Protocols developed
based on 2012 and 2013 experiences were implemented in 2014 to survey the Indian River.
Multiple aerial telemetry surveys were flown bracketing the entire spawning period of Chinook
Salmon. Survey aircraft were equipped with telemetry receivers and GPS to identify positions of
radio-tagged fish.
4.6.1. Variances
RSP Section 9.7.4.6 indicated that Chinook Salmon would be examined on selected spawning
grounds to test whether fish were equally vulnerable to being captured and radio-tagged. Results
from the 2012 Adult Salmon Distribution and Habitat Utilization Study filed in February 2013
(AEA 2013a) indicated that it would be unlikely to obtain sufficient numbers of fish samples
through spawning ground surveys to provide a robust mark rate, and in-turn, an estimate of the
numbers of fish above Devils Canyon (as established during the FERC Study Dispute process).
Therefore, prior to the 2013 field season, the study team decided to replace the spawning ground
surveys with the operation of a weir and underwater video system, along with a fixed-station
receiver site, on the Indian River to enumerate tagged and untagged fish, and establish mark
rates. This change was implemented as a variance in 2013 (ISR Section 4.1.8.3) and 2014, and
was a proposed modification to the Study Plan described in ISR Part C Section 7.1.2.1.2. The
methods and approach of using weirs to obtain this information was consistent with RSP
Sections 9.7.4.1.5 and 9.7.4.6. The same two metrics (i.e., mark rate and size distribution of
tagged/untagged fish) would be developed from fish counts at the weir (and telemetry detections)
that would have been developed from spawning ground surveys. However, as described in
Sections 4.1.4.2 and 5.1.2.4, the Indian River weir was rendered inoperable by a flood on June
26, 2014, prior to the onset of the Chinook Salmon run.
In response, the study team considered alternative methods for estimating the mark rate of
Chinook Salmon in the Indian River to ensure the study objective was met. One option
considered was to install a sonar unit at or near the weir site to count passing fish. However, the
advantages of being able to install a sonar unit soon after the weir was rendered inoperable were
outweighed by the fact that multiple salmon species would be present in the river by mid-July,
and thus Chinook Salmon could not be reliably counted (since sonar cannot distinguish between
species). The study team considered conducting a gillnet operation below the Indian River weir
site to capture and sample Chinook Salmon. Although physically handling fish is a reliable
method of collecting mark-rate and length data, physical conditions in the lower river were not
suitable for gillnetting, so it was unlikely crews could capture a sufficient number of fish. Also,
there may be negative impacts on fish health due to the capture and handling process. The study
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team also considered stream walks to count Chinook Salmon, but their experiences in 2012
proved this method was unlikely to succeed.
The timing of the loss of the weir was shortly before the onset of the Chinook Salmon run into
the Indian River. Thus, an immediate adjustment was required to ensure data were collected that
would fulfill the objectives of estimating the escapement of Chinook Salmon returning to the
Indian River and establishing a mark rate that could be used to make inferences about the relative
abundance among recovery locations (e.g., above the proposed dam site). AEA decided that the
best available option to fulfill the objectives was to increase the number of aerial spawner
surveys and aerial telemetry surveys (every third day during the spawning period) in the Indian
River. Instead of using the underwater video system at the weir, fish counts from aerial spawner
surveys and area-under-the-curve (AUC) methods (Ames and Phinney 1977; English et al. 1992)
were used to generate an escapement estimate for Chinook Salmon returning to the Indian River
in 2014. The marked fraction of Chinook Salmon present in the Indian River, as well as
estimates of residence time (i.e., the length of time Chinook Salmon were present in the river)
that were required for the AUC approach were estimated from aerial detections of radio-tagged
fish. Additional information related to AUC methods is provided in Appendix H. No fish
length-frequency information was collected using these methods.
4.7. Objective 7: Collect tissue samples to support the Fish
Genetics Study
AEA implemented the methods with respect to Objective 7 as described in the Study Plan with
no variances. The task for this study component was to collect genetic samples from adult
anadromous salmon in conjunction with addressing Objectives 1 and 2. Tissue samples were
taken from all radio-tagged salmon. Sample collections were coordinated with the Genetic
Baseline Study team (see ISR Study 9.14).
4.7.1. Variances
No variances from the methods described in the Study Plan occurred during the 2014 study
season.
4.8. Objective 8: Estimate the system-wide Chinook Salmon
escapement and the Coho Salmon escapement to the Susitna
River above the Yentna River, and the distribution of those fish
among tributaries of the Susitna River
In 2014, AEA implemented the methods with respect to Objective 8 as described in the Study
Plan, with the exception of modifications described in Section 7.1.2 of the ISR, and variances
described below (Section 4.8.1). A commonly applied two-event, capture-recapture experiment
was used to estimate the annual abundance of Chinook Salmon in the entire Susitna River
drainage, and the Coho Salmon abundance in the Susitna River above the Yentna River
confluence. Due to the river channel configuration and availability of acceptable fishing sites,
the abundance of Chinook Salmon for the entire Susitna River was designed to be the sum of two
independent experiments: the abundance of Chinook Salmon in the Lower River (Susitna River
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above the Yentna confluence) plus the abundance of Chinook Salmon in the Yentna River. At
the Lower River site, the capture event was provided by fishwheels and (and gillnets for Chinook
Salmon only) operated throughout the seasonal salmon migration. Substantial effort was made
to apply radio tags in proportion to abundance. Later in the salmon migration, recaptures were
collected from tributary weir and sonar sites forming the second event of the experiment. In the
Yentna River, the capture event was also provided by fishwheels (and gillnets for Chinook
Salmon only) operated throughout the seasonal salmon migration, with effort expended to apply
radio tags and also dart tags to fish in proportion to abundance. Radio tags were applied
according to average run timing, and dart tags were applied to every healthy Chinook Salmon
measuring 50 cm (19.7 in) METF or greater. The recaptures were collected from fishwheels
(and gillnets for Chinook Salmon only) located 19.3 kilometers (km; 12 miles [mi]) farther
upstream on the Yentna River. The abundance at the fishwheel sites on the Susitna (Chinook
and Coho salmon) and Yentna (Chinook Salmon) rivers was estimated. Length and timing
information from the tagged and untagged fish was used to assess the validity of most
assumptions. Behavior of radio-tagged fish following tagging also provided information for
evaluating two critical assumptions: knowing how many tagged fish have “entered” the
experiment, and whether their behavior compromised the experiment.
Two fishwheels and drift gillnets were operated on the Lower River from May 22 to August 26,
2014, to capture fish for marking with radio tags (Table A-1; Figures A-1, A-2, and A-6). Two
fishwheels and drift gillnets were operated on the Yentna River (RM 6) from May 22 to June 25
to capture fish for marking with radio tags and dart tags (Table A-2; Figures A-3, A-4, and A-7).
Lengths of tagged and untagged fish, and a tissue sample from radio-tagged fish (for genetics
sampling), were collected at each site. Dart tags (model FT-1-94 from Floy® Tag, Seattle, WA)
were 15 cm (6 in) long, yellow, and uniquely numbered, with the unique number printed twice
on each tag. Fish at Yentna RM 6 were tagged on the left side, immediately below the dorsal fin,
with the barb on the tag inserted deep enough to lock into the dorsal pterygiophores. A hole-
punch was used to make a hole in the adipose fin as a secondary mark to detect tag loss.
Weirs on tributaries of the Lower River were used to recapture tagged fish and estimate the
proportion of each species’ run that had a tag. At the weir recapture sites, Chinook Salmon were
counted visually and tagged fish were detected by a fixed-station receiver adjacent to the weir
(Table C-2). A weir was operated on the Deshka River from May 19 to September 2, 2014,
(Table B-1) and on Montana Creek from June 4 to September 21, 2014 (Table B-2). The use of
Montana Creek as a weir site represented a variance from the proposed Willow Creek site, as
described in the ISR (Part A, Section 4.8.1). Fish length was sampled at each site for estimating
the number of Chinook Salmon (METF ≥ 50 cm [19.7 in]) and testing assumptions of the mark-
recapture experiment. Sonar was operated on the Middle Fork Chulitna River from June 20 to
August 3, 2014 (the use of sonar rather than a weir represents a variance from the RSP, as
described in the ISR, Part A, Section 4.8.1). At the sonar site, the total number of fish passing
was counted by examining the recorded sonar files post-season, and tagged fish were detected by
a fixed-station receiver adjacent to each sonar site (Table C-2).
In the Yentna River drainage, two fishwheels and gillnet operations were conducted at RM 18 to
recapture tagged Chinook Salmon from May 24 to August 27, 2014 (Figure A-3). In 2013 and
2014, this represented a variance from the RSP (Section 9.7.4.8), as detailed in the ISR (Part A,
Section 4.8.1). All Chinook Salmon were examined for a dart tag and an adipose fin punch. If a
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tag was found, the distal half of the tag, containing one of the unique tag numbers, was clipped
off and retained as an absolute record of the tag found. Fish length was also sampled at this site
for testing assumptions of the mark-recapture experiment.
A two-event, capture-recapture experiment was also used to estimate the abundance of Coho
Salmon in the Lower River. Two fishwheels were used on the Lower River (PRM 33–34) to
capture Coho Salmon for marking with radio tags, from July 6 to August 26, 2014 (Table A-1;
Figures A-1, A-2, and A-6). Coho Salmon were counted, inspected for tags, and a sample
measured for length at the weirs on the Deshka River and Montana Creek, as described above.
4.8.1. Variances
RSP Section 9.7.4.8 indicated that weirs would be operated on the Middle Fork Chulitna River
and Willow Creek among other locations to inspect fish for estimating the proportion with tags.
However, Montana Creek was selected as a weir site instead of Willow Creek in 2014. Montana
Creek had a more uniform channel configuration and lower water velocity than Willow Creek.
The two creeks were located near each other, had similar discharge and watershed
characteristics, and had similar Chinook and Coho salmon run sizes. This variance also occurred
in 2013 (ISR Part A Section 4.8.1) and did not affect AEA’s ability to achieve study Objective 8.
A weir was not operated for Chinook Salmon on the Middle Fork Chulitna River in 2013 (see
Study 9.7 ISR, Part A, Section 4.8.1) or 2014. In June of both years, the stream discharge was
too high for weir installation; instead, the sonar unit designated for Lake Creek was reassigned to
the Middle Fork Chulitna River in order to obtain the counts necessary for the abundanc e
experiment. River discharges remained too high to install the weir at a later date. While a sonar
was operated in 2014, post-season data analysis revealed that focus and aiming problems
prevented obtaining reliable counts and length measurements. This variance did not prevent
meeting the abundance and distribution objectives for the Lower River and the Susitna River
abundance estimate component of study Objective 8 in either year but required additional
assumptions for generating the Chinook Salmon escapement estimate. Without the Middle Fork
Chulitna River, it was assumed that all Chinook Salmon stocks in the Susitna River were
adequately represented by the Deshka River and Montana Creek stocks for the tag recapture
sampling. Depending upon how similar the Middle Fork Chulitna River sampling results had
been to the Deshka River and Montana Creek results, the accuracy and precision of the Lower
River Chinook Salmon abundance estimate could be affected in either a positive or negative
way.
RSP Section 9.7.4.8 indicated that weirs would be operated on the Talachulitna River and Lake
Creek in the Yentna River drainage. No weir operations occurred at either location in 2014.
Results from the 2013 (see ISR Section 4.8.1 for a description of the 2013 variance) and 2014
studies showed that stream discharges in both systems remained too high for weir installation.
As proposed in ISR Section 7.1.2.6.1, AEA modified the Study Plan and used two fishwheels
and gillnets in the Yentna River (RM 18) as recapture methods in 2014 instead of weirs. This
modification helped AEA achieve study Objective 8 in 2014.
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5. RESULTS
This section summarizes results from 2012 and 2013 and presents detailed results from the 2014
salmon escapement study. Detailed results from the 2012 and 2013 studies were summarized
elsewhere (AEA 2013a, 2014a,c; Yanusz et al. 2013).
Data developed in support of this document are available for download at http://gis.suhydro.org/
Post_ISR/09-Fish_and_Aquatics/9.7-Salmon_Escapement/ and include the files:
9_7_ESCAPE_20141219_QC3_LGL_CurrySonarData_2014.xlsx;
9_7_ESCAPE_20141219_QC3_LGL_FishwheelData_2014.xlsx;
9_7_ESCAPE_20141219_QC3_LGL_GillnetData_2014.xlsx;
9_7_ESCAPE_20141219_QC3_LGL_Susitna Salmon Flat Tables 2014.xlsx;
9_7_ESCAPE_20141219_QC3_LGL_TagRecoveryData_2014.xlsx;
9_7_ESCAPE_20141219_QC3_LGL_TelemMgr Salmon Database 2014.zip;
9_7_ESCAPE_20141219_QC3_LGL_WatanaSonarData_2014.xlsx;
9_7_ESCAPE_20150106_QC3_LGL_Turbid Water Sonar_2014.xlsx;
SuWa LGL FAQ Escapement 201407 Indian River Weir Fish Passage Database QC3
KM 20140808.xlsx.
5.1. Objective 1: Capture, radio-tag, and track adults of five species
of Pacific Salmon in the Middle and Upper Susitna River in
proportion to their abundance. Capture and tag Chinook,
Coho, and Pink salmon in the Lower Susitna and Yentna rivers.
A total of 9,286 adult salmon of five species were radio-tagged during this three-year study.
Table 5.1-1 presents the number of tags implanted and tagged fish tracked for each species in
each year of the study. While the tagged species were consistent each year in the Middle River,
they varied each year in the Lower River (Table 5.1-1) in order to assist ADF&G with fulfilling
statewide objectives regarding escapement to the Susitna River Basin.
The size of fish radio-tagged ranged from 28 cm (11.0 in) to 110 cm (43.3 in.) METF. Since
fishwheels were the primary capture method and have the potential for biased catch based on
size, several analyses for size-selective capture and tagging were conducted. When size-
selective capture was detected adjustments were made as detailed below. During each study
year, tracking began with the first tags implanted in the Lower River and continued through
October or November. Detailed results related to fish capture, tagging, and tracking in 2014 are
presented below and in Appendices A, B, and C.
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5.1.1. Fish Capture and Fish Tagging
5.1.1.1. Lower River
In the Lower River, 2,048 Chinook Salmon (1,471 large, 577 small) were caught and 659 large
Chinook Salmon were radio-tagged (Table A-1; Figure A-6, Figure A-9). The peak of Chinook
Salmon catch in the fishwheels occurred on May 29 (111 fish) and CPUE for an individual
fishwheel peaked at 5.6 Chinook Salmon per hour (west bank). Daily radio-tag deployment in
the Lower River peaked at 39 Chinook Salmon on June 5. Seventy-seven percent (129) of large
Chinook Salmon captured using gillnets in the Lower River were radio-tagged. Large Chinook
Salmon captured in the Lower River averaged 67.6 cm [26.6 in] METF and small Chinook
Salmon averaged 39.1 cm [15.4 in] METF (Table A-4).
A total of 1,513 Coho Salmon were captured in the Lower River in 2014, of which 640 were
radio-tagged at the fishwheels. The peak catch occurred on August 3 (128 fish) and CPUE for an
individual fishwheel peaked at 7.0 fish per hour (west bank). The daily number of radio tags
deployed peaked on July 28 (71 tags).
Pink Salmon were the most abundant species captured in the Lower River (13,934 fish). Daily
fishwheel catches peaked on July 20 (2,050 fish) and CPUE peaked at 130 fish per hour (west
bank). A total of 198 Pink Salmon were radio-tagged, and the most tags deployed on a single
day was 16 (July 24). Similar to Coho Salmon, Pink Salmon catches were consistently higher in
the west bank fishwheel relative to the east bank fishwheel.
A total of 6,577 Chum and 853 Sockeye salmon were also captured in the Lower River in 2014.
5.1.1.2. Yentna River
Of the 3,025 Chinook Salmon (1,357 large, 1,668 small) captured at Yentna RM 6, the majority
(87 percent) were captured in fishwheels and the remainder (13 percent) in gillnets (Table A-2).
Daily catch peaked at 275 fish on June 4. The magnitude and timing of the peak CPUE for
Chinook Salmon was very similar for the north and south bank fishwheels (Figure A-10). The
average length of large Chinook Salmon captured at Yentna RM 6 (66.9 cm [26.3 in] was similar
to that of fish captured in the Lower River, while small Chinook Salmon at Yentna RM 6
averaged 34.9 cm (13.7 in) METF, which was 4.3 cm (1.7 in) less than at the Lower River. A
total of 190 large Chinook Salmon were radio-tagged at the Yentna RM 6 fishwheels (Table A-2;
Figure A-7), which was 7.3 percent of the total fishwheel catch. In the gillnetting at Yentna RM
6, 106 large Chinook Salmon were radio-tagged, which was 27 percent of the gillnet catch.
Radio-tag deployment for Chinook Salmon at Yentna RM 6 peaked at 24 tags on June 2.
Of the 2,305 adult Chinook Salmon (1,375 large, 930 small) captured at Yentna RM 18, the
majority (95 percent) were captured in fishwheels, and the remaining 5 percent in gillnets (Table
A-2). Daily catch peaked at 171 fish on June 5. The magnitude and timing of the peak CPUE
for Chinook Salmon was very similar for the north and south bank fishwheels (Figure A-10). At
Yentna RM 18, large and small Chinook Salmon averaged 66.8 cm (22.3 in) and 37.0 cm (14.6
in) METF, respectively (Table A-4).
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5.1.1.3. Middle River
In the Middle River, 877 Chinook Salmon (672 large, 205 small) were captured in 2014 of which
876 were captured in fishwheels and one was captured in a gillnet (Table A-5,Table A-57). The
daily catch of large Chinook Salmon peaked at 58 fish on July 1 (Figure A-11), and CPUE was
highest for large Chinook on June 30 (1.6 fish/hour at Site 1; Figure A-12). The mean length of
large Chinook Salmon captured in the Middle River (71.6 cm [28.2 in]; Table A-6) was greater
than the mean length of large Chinook Salmon captured in the Lower River (67.6 cm [26.6 in])
or Yentna RM 6 (66.9 cm [26.3 in]) fishwheels (Table A-4). Radio tags were applied to 590
large and 32 small Chinook Salmon captured at the fishwheels (Table A-3; Figure A-8), which
represented 88 and 16 percent of the fish captured, respectively. Daily tag deployment peaked at
51 for large Chinook Salmon and 3 for small Chinook Salmon.
In total, 1,552 Chum Salmon were captured in the Middle River of which 1,469 were captured in
fishwheels and 83 in gillnets (Table A-5). Daily catch for Chum Salmon peaked at 89 fish on
August 11 and CPUE peaked at 3.7 fish/hour on August 10 (Site 3; Figure A-12). Chum Salmon
caught in the Middle River averaged 57.9 cm (22.8 in) METF (Table A-6). Radio tags were
applied to 200 Chum Salmon at the fishwheels, or 14 percent of the fishwheel catch (Table A-3;
Figure A-8). Daily tag deployment peaked at 12 for Chum Salmon.
A total of 377 Coho Salmon (375 large, 2 small) were captured in the Middle River of which 198
were caught in fishwheels and 42 in gillnets (Table A-5). Daily catch peaked on August 22 (30
fish) and CPUE peaked at 1.4 fish/hour at Site 3 on July 29 (Figure A-12). Coho Salmon
captured in the Middle River averaged 54 cm (22.8 in; Table A-6). A total of 230 Coho Salmon
(daily max = 13 tags) were radio-tagged in the Middle River in 2014 of which 212 were captured
at fishwheels and 18 in set gillnets (Table A-3; Figure A-8).
In total, 7,473 Pink Salmon were caught in the Middle River fishwheels in 2014 (Table A-5).
Peak daily catch was 979 fish (July 29) and peak daily CPUE was 52.0 fish/hour at Site 3 (July
29; Figure A-12). The mean length of Pink Salmon captured in the Middle River was 46 cm
(18.1 in) METF (Table A-6). A total of 201 Pink Salmon were radio-tagged (2.7 percent of all
fish caught), with a peak daily allocation of 15 tags (Table A-3; Figure A-8).
Two-hundred and thirty four Sockeye Salmon (223 large, 11 small) were caught in 2014, of
which 223 were caught at fishwheels and 11 in gillnets (Table A-5). Peak catch occurred on July
28 (13 fish) and peak CPUE occurred on July 22 and August 7 at Site 2 (0.7 fish/hour; Figure A-
12). The mean length of Sockeye Salmon was 49 cm (19.3 in) METF (Table A-6). Radio tags
were applied to 200 Sockeye Salmon (95 percent of total catch), with a peak of 13 tags deployed
on a given day (Table A-3; Figure A-8).
The largest proportion of Chum Salmon were captured at Site 1 (39.6 percent), whereas the
largest proportion of Sockeye Salmon were captured at Site 2 (42.2 percent), and the largest
proportion of Chinook (48.2 percent), Coho (59.1 percent), and Pink (58.7 percent) salmon were
captured at Site 3. In general, radio tags were deployed in proportion to catch for Chinook and
Sockeye salmon, but less so for Pink, Chum, and Coho salmon (Figure A-11).
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Seven other fish species were captured and released at the Middle River fishwheels, including 68
Rainbow Trout O. mykiss, 67 Round Whitefish Prosopium cylindraceum, 17 Arctic Grayling
Thymallus arcticus, 13 Humpback Whitefish Coregonus pidschian, 13 Longnose Sucker
Catostomus catostomus, 8 Dolly Varden Salvelinus malma, and 2 Burbot Lota lota (Table A-6).
During Middle River gillnet operations, 1 small Chinook, 83 Chum, 42 Coho, and 11 Sockeye
salmon (including one fish measuring less than 40 cm METF) were captured (Table A-5). Other
species captured during gillnetting included Rainbow Trout, Round Whitefish, Arctic Grayling,
Longnose Sucker, and Bering Cisco Coregonus laurettae.
5.1.1.4. Programmatic Summary
Catch rates in the Lower River, Yentna River, and Middle River were sufficient to achieve all of
the requirements of study Objective 1, and met or exceeded the majority of species-specific tag
goals in each of the three study years. There were only seven cases where less than 90 percent of
the allocated radio tags were deployed. These cases included large Chinook Salmon in the
Lower River in 2012 and 2013 (88 and 83 percent of tags were deployed, respectively), and in
the Yentna River in 2013 (61 percent of tags were deployed). Catches of large Chinook Salmon
at both of these locations were substantially greater than the tag goals, and not meeting the tag
targets in these cases was an artifact of investigators attempting to deploy tags proportional to
abundance over the entire run rather than due to low catch rates. The remaining three cases
occurred in the Middle River and included large Chinook Salmon in 2012 (88 percent of tags
deployed), small Chinook Salmon in 2014 (32 percent of tags deployed), and Sockeye Salmon in
2012 and 2013 (35 and 69 percent of tags deployed, respectively). In these cases, too few fish
were captured to meet the tag goals.
Factors that influenced catches over the three-year study period included the timing of ice-out,
periods of high river discharge, changes in flow patterns at the capture sites, the amount of
fishing effort, and differences in relative fish abundance among years. In the Lower River, the
timing of ice-out in 2012 was similar to past records, was approximately two weeks late in 2013,
and in 2014 was several days earlier than in the past. As a result, the start dates of fishwheel
operations in the Lower River varied: May 25 in 2012, June 3 in 2013, and May 22 in 2014.
Nonetheless, the number of Chinook Salmon captured in the Lower River among years was
similar and ranged from 1,916 (2012) to 2,063 (2013) fish. On the Yentna River, catches of
Chinook Salmon increased from 2,295 fish in 2013 to 3,033 fish in 2014. In the Middle River,
the same two fishwheel sites (sites 1 and 2) used during the 1980s studies were used successfully
from 2012 to 2014. Due to changes in flow patterns observed in 2013 that made it difficult to
operate the Site 1 fishwheel when river discharge decreased below 17,500 cfs at the Gold Creek
gauge, a third fishwheel site (Site 3) was added to increase catch rates. The addition of a third
fishwheel increased fishing effort in 2013 (starting July 17) and 2014 relative to 2012. A
substantial portion of catches in 2014 was attributed to the Site 3 fishwheel (30 percent or greater
capture of each salmon species). Despite increasing fishing effort in the Middle River, catch in
2014 was lower than in 2013 for all salmon species, but higher than in 2012 for all species
except Chum Salmon. Apart from occasional temporary shut downs due to high river discharge,
fishing effort across all locations was nearly continuous each season.
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Fishwheel effectiveness was assessed using fixed-site sonar (DIDSON in 2012/2014, ARIS in
2013) at one of the Middle River fishwheels (Site 1) in each study year. Sonar data confirmed
that the fishwheel sampling adequately covered the leading edge of the Chinook Salmon run in
June and a representative portion of the run was captured in July. In September, the sonar data
were useful for quantifying the relative abundance of passing fish (i.e., Chum, Coho, and
Sockeye salmon), particularly when river discharge and turbidity decreased and the fishwheels
could not be operated effectively at any of the sites. Under these river conditions, sonar counts
were useful for informing Coho Salmon tag rates (e.g., for gillnetting in 2014).
Sonar was also used to assess the behavior of fish as they approached the Site 1 fishwheel.
Sonar imagery collected at Site 1 showed that the vast majority of fish migrated upstream within
13 m (43 ft) of shore. As a result, lead nets were hung between the shore-side pontoons of the
Middle River fishwheels and the adjacent riverbank to increase catch rates (particularly at Site 1
where the fishwheel was held up to 50 ft offshore with spar poles at times). Information on diel
pattern obtained from the Site 1 sonar data were useful for informing the crew as to the best
times to fish in order to achieve optimal catch rates.
Limitations of using sonar to evaluate fishwheel effectiveness were evident in July and August
when large numbers of fish and multiple species were present. Under these conditions it took a
substantial amount of effort to review the imagery, and apart from large Chinook Salmon, fish
observed in the sonar imagery could not be identified by species. Fishwheel effectiveness was
difficult to assess during this period, however, by this time protocols for operating the fishwheels
under a range of river conditions had been established and there was not likely anything more
that could be done to increase fishwheel effectiveness.
For all five species of salmon, 2014 catches at the Middle River fishwheels were lower than in
2013, despite a third fishwheel being operated for the entire 2014 season (Table A-8). Except for
Chum Salmon, 2014 salmon catches were higher than in 2012. By excluding 2014 catch years at
the Site 3 fishwheel and equalizing effort for comparison across years, a different pattern
emerges. Fewer Chinook, Chum, Coho, and Pink salmon were captured in 2014 than in 2013
and 2012.
Reviewing total catch of Chinook Salmon in the Middle River fishwheels across years showed
that 2013 was the highest (952 fish), followed by 2014 (877 fish) and 2012 (566 fish). High
catches in 2013 were largely due to the abundance of small Chinook Salmon (336 fish or 55
percent of the catch). More large Chinook Salmon were captured in 2014 (672 fish) than in 2012
(422 fish) or 2013 (616 fish). The majority of Chinook Salmon were captured at the Site 1
fishwheel in 2012 (60 percent) and 2013 (82 percent), whereas only 41 percent of catch occurred
at Site 1 in 2014. Operating a third fishwheel (at Site 3) throughout the entire run in 2014
increased overall catch (48 percent of Chinook Salmon were caught at Site 3). Over eight years
of operation (1981–1985 and 2012–2014), catch of Chinook Salmon at the Middle River
fishwheels was highest in 1984 (1,589 fish) and lowest in 1981 (284 fish; Table A-8; Figure A-
13). Catches in 2012, 2013, and 2014, ranked 7th, 4th, and 5th highest among these years,
respectively.
Chum Salmon catch at the Middle River fishwheels in 2014 (1,469 fish) was similar to 2012
(1,734 fish) but was 57 percent lower than in 2013 (3,417 fish; Table A-8; Figure A-14). The
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2014 Chum Salmon catch was also similar to annual average catch from the 1980s (1,881 fish),
but during that period annual catch varied more widely (range: 861–4,228 fish).
In 2014, Coho Salmon catch of 335 fish was greater than the average from the 1980s
(average = 211 fish) and 2012 total catch (265 fish; Table A-8; Figure A-15); however, the 2014
catch was more than five times lower than 2013 (1,723 fish).
Compared with other even years, the 2014 catch of Pink Salmon (7,473 fish) was higher than in
1982 (7,302 fish) and 2012 (4,705 fish), but substantially lower than catch in 1984 (17,394 fish;
Table A-8; Figure A-16).
From 2012 to 2014, annual catch of Sockeye Salmon at the Middle River fishwheels was among
the lowest on record (Table A-8). In 2012, 2013, and 2014, a total of 100, 276, and 223 Sockeye
Salmon, respectively, were captured at the Middle River fishwheels. In the 1980s, annual
catches averaged 307 fish (range: 161–469 fish; Table A-8; Figure A-17).
5.1.2. Numbers and Size of Marked and Unmarked Fish Recovered at Selected
Locations
5.1.2.1. Deshka River Weir
An estimated 13,908 Chinook Salmon measuring 50 cm (19.7 in) METF or greater passed the
Deshka River weir during May 19 to September 2, 2014, out of a total count of 16,335 Chinook
Salmon of all sizes (Table B-1). One hundred twenty-five, or 0.9 percent, were radio-tagged fish
and were assumed to have spawned above the weir (Table B-1). The mean length of radio-
tagged Chinook Salmon released in the Lower River (69.9 cm [27.5 in]) was larger than that of
Chinook Salmon (METF ≥ 50 cm [19.7 in]) that passed the Deshka River weir (67.9 cm [26.7
in]; Table B-3).
A total of 11,578 Coho Salmon were counted at the Deshka Creek weir during July 4 to
September 2, 2014, all of which were estimated to be 40 cm (15.7 in) METF or greater (Table B-
1). Sixty-eight, or 0.59 percent, were radio-tagged fish and were assumed to have spawned
above the weir. The mean length of radio-tagged Coho Salmon released in the Lower River
(52.6 cm [20.7 in]) was smaller than that of Coho Salmon (METF ≥ 40 cm [15.7 in]) that passed
the Deshka River weir (55.8 cm [22.0 in]; Table B-3).
5.1.2.2. Montana Creek Weir
An estimated 1,212 Chinook Salmon measuring 50 cm (19.7 in) or greater passed the Montana
Creek weir during June 4 to September 21, 2014, out of a total count of 1,217 Chinook Salmon
of all sizes (Table B-2). Fifteen, or 1.2 percent, were radio-tagged fish (Table B-2) and were
assumed to have spawned above the weir. The mean length of radio-tagged Chinook Salmon
released in the Lower River (69.9 cm [27.5 in]) was slightly larger than Chinook Salmon (METF
≥ 50 cm) that passed the Montana River weir (68.7 cm [27.0 in]; Table B-3).
A total of 934 Coho Salmon were counted at the Montana Creek weir during August 3 to
September 21, 2014, all of which were estimated to be 40 cm (15.7 in) METF or greater (Table
B-2). Four, or 0.43 percent, were radio-tagged fish and were assumed to have spawned above
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the weir (Table B-2). The mean length of radio-tagged Coho Salmon released in the Lower
River (52.6 cm [20.7 in]) was smaller than that of Coho Salmon (METF ≥ 40 cm [15.7 in]) that
passed the Montana Creek weir (56.6 cm [22.3 in]; Table B-3).
5.1.2.3. Middle Fork Chulitna River Sonar
An ARIS sonar was operated on the Middle Fork Chulitna River (Figure 3-1) from June 20 to
August 3, 2014. Post-season analysis of echograms resulted in a total count of 772 Chinook
Salmon measuring 50 cm (19.7 in) METF or greater. Forty-two Chinook Salmon, or 5.4 percent,
were radio-tagged fish. Many of the sonar echograms were of poor quality, the total count
seemed unusually low, and fish lengths estimated from the sonar appeared suspiciously large,
and the data were not used further. It was determined post-season that improper focusing
occurred during data collection.
5.1.2.4. Indian River Weir
The underwater video system at the Indian River weir was operated 24 hours a day, and collected
89 hours of video footage from 1:30 P.M. on June 22 to 6:29 A.M. on June 26, 2014 (Table B-4).
Due to poor visibility, 5.2 hours of video imagery collected on June 26 was not reviewed.
Persistent rain on June 25 and June 26 contributed to high-water conditions in the Susitna
(Figures 5.1-1 and 5.1-2) and Indian rivers. At approximately 6:29 A.M. on June 26, due to high
flows and debris loading, the anchoring system failed and the majority of the weir components
were flushed approximately one mile down river. A portion of the weir components were
retrieved from July 4–8, and the remainder were retrieved on August 15 when water levels were
considerably lower. In total, three Rainbow Trout and two Round Whitefish were observed on
the video footage, but no adult salmon (Table B-4).
5.1.2.5. Programmatic Summary
The combination of Deshka River and Montana Creek weirs provided a robust second -event
sample for evaluating sources of potential bias (heterogeneity in probability) of capture for the
mainstem Susitna River Chinook and Coho salmon mark-recapture experiments. When size-
biased sampling was detected using these two sites for second event sampling, substantial
numbers of all size classes of Chinook and Coho salmon in the mainstem Susitna River were
detected at these sites, particularly at the Deshka weir site. As such, size-based capture
heterogeneity in the first event was reliably detected and the appropriate size-stratification
applied to minimize bias when estimating abundance and distribution.
In addition to evaluating size, the weir data allowed for an evaluation of the representation of
tagging across each run. Radio-tagged Chinook and Coho salmon that were recaptured at
Montana and Deshka weir proved to be tagged across the entire time-frame of the marking event,
ensuring a non-zero probability of capture for fish tagged both early and late in the run of fish
past the tagging site. As the numbers of fish that can be sampled at these two sites is “fixed” at
the escapement for these two tributaries, the precision in estimates of spawning abundance and
distribution can only be increased by increasing the number of radio-tags deployed during the
marking event, or by identifying additional viable second event sampling sites.
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Operating a floating picket weir and underwater video system in the lower Indian River did not
provide reliable second-event sampling for the Middle River tag site. In 2013, the Indian River
weir was successfully operated throughout the majority of the Chinook Salmon run; however, the
video system was shut down temporarily from July 19–20, and then permanently on August 20,
due to high-water events. In 2014, the weir was rendered inoperable due to a high-water event in
late June, prior to the onset of the Chinook Salmon run. During each of these high-water events,
discharge of the Susitna River at the Tsusena Creek gauge increased to over 20,000 cfs. At low
to moderate Indian River discharges, the site was ideal for weir installation and day-to-day
access and operation; however, discharge increased substantially during heavy rain and the
effectiveness of the site for sampling was diminished. Other tributaries in the Middle River (e.g.,
Portage Creek) would likely respond to heavy rains in a similar manner as the Indian River.
Based on these findings, tributary weirs in the Middle River are not an effective method for
assessing the numbers and size of marked and unmarked fish.
5.1.3. Assessing Any Stock- and Size-selective Capture
5.1.3.1. Use of ARIS to Assess Middle River Fishwheel Effectiveness and Fish
Approach Behavior
Catch-per-unit-effort at the Site 1 ARIS unit (located immediately downstream of the Site 1
fishwheel; see Figures 3-1 and 4.1-1), or the number of targets counted per hour of imagery
reviewed, increased over time in June (Figure A-18, Figure A-19). The ARIS CPUE was zero
during the first two days of operation (June 3–4) and only increased slightly from June 5 to June
12 (0.0–0.6 fish/hour). The ARIS CPUE showed a moderate increase from June 13 to June 17
(1.8–6.5 fish/hour), but increased substantially afterwards (10.9–37.0 fish/hour from June 18–
25). In September, CPUE at the ARIS showed peaks on September 1 (37.9 fish/hour) and
September 7 (39.0 fish/hour), but steadily declined from September 8 through September 28.
In June, trends in CPUE at the Site 1 fishwheel were similar to counts at the ARIS unit (Figure
A-20). No adult salmon were captured at the Site 1 fishwheel from June 6 to June 12. The
fishwheel CPUE was low from June 13 to June 16 (0.1–0.2 fish/hour), and peaked at 1.0
fish/hour on June 17. In September, CPUE at the Site 1 fishwheel decreased dramatically after
August 30 (0.9 fish/hour), and remained low (or zero) through September 7 when the fishwheel
was stopped for the season (Figure A-20). This trend contrasts with the ARIS CPUE which
peaked in early September and remained relatively high through mid-September (Figure A-19).
This decrease in CPUE at the Site 1 fishwheel (Figure A-20) appeared to be related to turbidity,
which decreased steadily from 66 NTU on August 29 to 21 NTU on September 7 (Figure A-19).
Similar patterns observed in ARIS and fishwheel CPUE in June indicated that the ascending limb
of the Chinook Salmon run was captured at the Middle River fishwheels. In contrast, the ARIS
data suggested low fishwheel catches of Coho Salmon in the first week of September were not
representative of abundance. From September 4–7 for example, CPUE at the ARIS ranged from
19.5–39.0 fish/hour with a net upstream count of 57–147 fish per day (during periods when the
fishwheel was operational), yet no adult salmon were captured at the Site 1 fishwheel. Low
Coho Salmon catches (Figure A-12) at the Site 1 fishwheel from late August through early
September were likely due to low turbidity and not to low relative abundance. Anticipating this
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condition, the study team switched to gillnet operations to catch and tag Coho for this part of the
run.
The proportion of targets observed on the Site 1 ARIS that were first detected within the capture
range of the Site 1 fishwheel (~ 6 m [19.7 ft]) appeared to be influenced by river discharge.
From June 3 to June 15, when fish measuring 50 cm TL (19.7 in) or greater passing Site 1 were
likely Chinook Salmon, Susitna River discharges at the Gold Creek gauge were 19,800 cubic feet
per second (cfs) or less and only 27 percent of targets were within 6 m (19.7 ft) of the transducer
(Figure A-21). From June 16 to June 25, Susitna River discharges were 21,800 cfs or greater,
and the proportion of fish passing within 6 m (19.7 ft) of the transducer increased to 47 perce nt.
From August 29 to September 30, when most fish measuring 40 cm TL (15.7 in) or greater
passing Site 1 were likely Coho Salmon, the vast majority (88 percent) of targets passed the Site
1 ARIS within 6 m of the transducer. These observations suggested that higher river discharge,
likely through water velocity, can affect the cross-channel distribution of migrating Chinook
Salmon such that they migrate closer to the bank. The effect was likely more pronounced on
Coho Salmon due to their shorter body length.
During the periods of monitoring with ARIS at Site 1, migrations were lowest in the early part of
the day. In June, 58 percent of upstream-moving fish measuring 50 cm TL (19.7 in) or greater
(presumably Chinook Salmon) passed the Site 1 ARIS between noon and midnight (Figure A-
22). Fish passage was lowest early in the morning (~1:00–5:00 A.M.). In September, fish
passage (presumably mostly Chum and Coho salmon) was more evenly distributed throughout
the day, with 58 percent of fish measuring 40 cm TL (15.7 in) or greater passing between 7:00
A.M. and 6:00 P.M. Fish passage in September was lowest early in the morning (~0:00–5:00
A.M.).
5.1.3.2. Bank Orientation & Capture Probability by Spawning Location (Middle River)
Results of contingency table tests comparing the bank of capture to the bank where fish were
assigned a spawning destination did not indicate that radio-tagged large Chinook (χ2 = 3.3; P =
0.07), Pink (χ2 = 0.1; P = 0.72), or Sockeye (χ2 = 2.7; P = 0.15) salmon were bank-oriented when
passing through the Middle River. Too few small Chinook and Chum salmon returned to left-
bank spawning areas to reliably evaluate bank orientation with a contingency table. Specifically,
95 percent (n = 21) of Chum Salmon tagged on the left bank (when looking downstream), and
100 percent (n = 82) of Chum Salmon tagged on the right bank, were assigned to right-bank
spawning areas. All small Chinook Salmon returned to spawning areas on the right bank
regardless of whether they were captured on the left (n = 2) or right (n = 17) bank.
Mainstem spawning populations did not appear more vulnerable to recapture than those fish
bound for tributaries (χ2 = 0.1; P = 0.71). Of the 34 radio-tagged salmon released and recaptured
at the Middle River fishwheels that were subsequently assigned spawning destinations, 29 (85
percent) were assigned to tributaries and five (15 percent) were assigned to mainstem areas.
Similar proportions were observed for radio-tagged fish released at the Middle River fishwheels
that were never recaptured (87 percent to tributaries and 13 percent to mainstem areas).
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5.1.3.3. Size-related Comparisons
The following subsections summarize the results of comparisons made between cumulative
length-frequency distributions of fish captured and sampled in the Lower River, Yentna River,
and Middle River. Two-sample KS tests were used to detect significant differences between the
distributions. When interpreting the results of KS tests, it was important to consider both the
sample sizes of each distribution and the P-value of the test. For example, in a case where the
sample sizes for each distribution were very large and a significant test result was obtained, it
was possible that the KS test was detecting small differences between the cumulative length-
frequency distributions that had little potential to result in any bias. Despite a significant test
result in such a case, there may be no biologically meaningful difference between the two
cumulative length-frequency distributions.
5.1.3.3.1. Lower River
Cumulative length-frequency distributions for all Chinook Salmon captured at the Lower River
tagging site showed significant differences between the size distributions of fish caught at the
west bank fishwheel, the east bank fishwheel, and mid-river gillnetting sites. Chinook Salmon
caught in mid-river gillnets were larger than fish caught in the west bank fishwheel (D = 0.442,
P < 0.001) and the east bank fishwheel (D = 0.387, P < 0.001; Figure A-23; Table A-9).
Chinook Salmon caught in the west bank fishwheel were smaller than those from the east bank
fishwheel (D = 0.111, P < 0.001; Figure A-23; Table A-9). Average lengths (METF) of Chinook
Salmon for each capture station were 75.3 cm (29.6 in) for mid-river gillnets, 57.7 cm (22.7 in)
for the west bank fishwheel, and 59.5 cm (23.4 in) for the east bank fishwheel.
For Chinook Salmon measuring 50 cm (19.7 in) METF or greater, a significant difference was
detected between the length distributions of fish captured at the Lower River tagging site and
only those fish radio-tagged at that site (D = 0.145, P < 0.001; Figure A-24; Table A-9). This
difference was due largely to the tagging strategy used at the site, which called for Chinook
Salmon less than 58 cm (22.8 in) METF to be tagged at approximately one-third the rate of
Chinook Salmon measuring 58 cm (22.8 in) METF or greater. This tagging strategy was
intended to reduce the effects of size-selective capture by the fishwheels. No significant
difference was detected between the length distributions of Chinook Salmon measuring 58 cm
(22.8 in) METF or greater caught at the Lower River site and those tagged (D = 0.03, P = 0.797;
Table A-9).
The cumulative length-frequency distributions for all Coho Salmon captured at the Lower River
tagging site was significantly different between the west bank fishwheel and the east bank
fishwheel (D = 0.083, P = 0.011; Table A-9). For Coho Salmon (METF ≥ 40 cm), the
cumulative length-frequency distributions were not significantly different between the total catch
and those tagged (D = 0.023, P = 0.886; Table A-9).
The cumulative length-frequency distributions for Pink Salmon tagged at the Lower River
tagging site were not significantly different between the west bank fishwheel and the east bank
fishwheel (D = 0.145, P = 0.14; Table A-9). For Pink Salmon, length data were collected only
for fish that were radio-tagged so no further comparisons can be made (Figure A-24).
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The cumulative length-frequency distribution for Chinook Salmon sampled at the Deshka River
weir was not significantly different than that for all radio-tagged fish above the tagging site
(D = 0.09, P = 0.101; Figure A-25).
The cumulative length-frequency distribution for Chinook Salmon sampled at the Montana
Creek weir was significantly different than that for all radio-tagged fish above the tagging site
(D = 0.13, P = 0.006; Figure A-25).
5.1.3.3.2. Yentna River
Cumulative length-frequency distributions for Chinook Salmon captured at the Yentna RM 6
tagging site showed significant differences between the size distributions of fish caught at the
south bank fishwheel, the north bank fishwheel, and mid-river gillnetting sites. Chinook Salmon
caught in mid-river gillnets were larger than fish caught in the south bank fishwheel (D = 0.519,
P < 0.001) and the north bank fishwheel (D = 0.658, P < 0.001; Figure A-26; Table A-9).
Chinook Salmon caught in the north bank fishwheel were smaller than those from the south bank
fishwheel (D = 0.155, P < 0.001; Figure A-26; Table A-9). Average lengths (METF) of Chinook
Salmon for each capture station were 72.0 cm (28.4 in) for mid-river gillnets, 48.9 cm (19.3 in)
for the south bank fishwheel, and 43.2 cm (17.0 in) for the north bank fishwheel. For Chinook
Salmon measuring 50 cm (19.7 in) METF or greater, no significant difference was detected
between the length distributions of fish captured at the Yentna RM 6 tagging site and only those
fish dart-tagged at that site (D = 0.005, P = 1.00; Figure A-27; Table A-9).
Cumulative length-frequency distributions for all Chinook Salmon captured at the Yentna RM 18
recapture site also showed significant differences between the size distributions of fish caught at
the south bank fishwheel, the north bank fishwheel, and mid-river gillnetting sites. Chinook
Salmon caught in mid-river gillnets were larger than fish caught in the south bank fishwheel
(D = 0.528, P < 0.001) and the north bank fishwheel (D = 0.671, P < 0.001; Figure A-26; Table
A-9). Chinook Salmon caught in the north bank fishwheel were smaller than those from the
south bank fishwheel (D = 0.25, P < 0.001; Figure A-26; Table A-9). Average lengths (METF)
of Chinook Salmon for each capture station were 77.9 cm (30.7 in) for mid-river gillnets, 59.3
cm (23.3 in) for the south bank fishwheel, and 50.7 cm (20.0 in) for the north bank fishwheel.
The cumulative length-frequency distribution for Chinook Salmon sampled at the Yentna RM 18
recapture site was not significantly different than that for all dart-tagged fish above the tagging
site (D = 0.036, P = 0.265; Figure A-28).
5.1.3.3.3. Middle River
In the Middle River, the cumulative length-frequency distributions for Chum Salmon at site 2
was significantly different from that at site 1 (D = 0.14, P = 0.01) and site 3 (D = 0.15, P < 0.01).
Also, Pink Salmon length distributions differed between sites 1 and 3 (D = 0.09, P = 0.04; Figure
A-29; Table A-10). Sample sizes were large for these comparisons (n: 342–449) and tagging
effort was distributed amongst the sites, so it was unlikely these differences introduced
significant bias. Among sites, mean lengths were greatest at Site 2 for Chinook (66.4 cm; 26.2
in), Chum (58.6 cm; 23.1 in), Coho (55.6 cm; 21.9 in), and Sockeye (50.0 cm; 19.7 in) salmon;
but greatest at Site 3 for Pink Salmon (46.0 cm; 18.1 in). Mean lengths were smallest at Site 1
for Chum (57.5 cm; 22.7 in), Coho (53.8 cm; 22.7 in), Pink (45.5 cm; 17.9 in), and Sockeye
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(48.5 cm; 19.1 in) salmon; but smallest at Site 3 for Chinook Salmon (62.1 cm; 24.5 in). Small
Chinook Salmon (METF < 50 cm [19.7 in]) comprised 23 percent of all Chinook Salmon caught
in 2014 (versus 35 percent in 2013); and 5 percent of Sockeye Salmon caught in 2014 measured
less than 40 cm (15.7 in) METF (versus 36 percent in 2013).
Cumulative length-frequency distributions for salmon captured at the Middle River fishwheels
were significantly different than those of radio-tagged fish for small Chinook (D = 0.77,
P < 0.01) and Pink Salmon (D = 0.15, P < 0.01), but not for large Chinook, Chum, Coho, or
Sockeye salmon (Figure A-30; Table A-10). For small Chinook and Pink salmon, these results
were consistent with tagging effort as it was not random across all sizes, but instead was limited
to the larger-sized segment of these fish captured in the fishwheels.
5.1.3.3.4. Programmatic Summary
Achieving the goals of this study was dependent in part on tagging a representative group of fish
from the entire population. However, fishwheels have been shown to be size and species
selective for adult salmon. Meehan (1961) showed that fishwheels on the Taku River caught a
larger proportion of smaller-sized Chinook Salmon compared with samples collected on the
spawning grounds. Meehan (1961) also showed that Chinook and Coho salmon were least
susceptible to recapture in a fishwheel, while Pink Salmon were most easily recaptured. In 1981
and 1982 on the Susitna River, ADF&G (1983a) compared observed and expected mark rates on
the spawning grounds and found that fishwheels operated near Curry were species selective:
Chinook and Chum salmon catches were biased low, and Pink Salmon catches were biased high.
Meehan (1961) hypothesized that size selectivity was due to larger fish avoiding the fishwheel,
or migrating in faster and deeper water away from shore, relative to smaller fish. A tendency for
large salmon to swim upstream farther from the bank than smaller ones in locations where the
river gradient is low and velocities offshore are modest also has been suggested by ADF&G
(1983a) and Hughes (2004). In contrast, there is also evidence showing that fishwheels can
catch a representative sample of salmon when deployed in areas where elevated water velo cities
force fish to migrate near shore (Link and Nass 1999).
KS tests indicated some size selectivity in capture (toward disproportionate capture of smaller-
sized fish) in the Lower River fishwheels. Size-selective sampling was detected for Chinook
Salmon radio-tagged at the Lower River site in 2013 and 2014, even where capture was achieved
using a combination of fishwheels and drift gillnets. Chinook Salmon measuring less than 58 cm
(22.8 in) METF were radio-tagged at approximately one-third the rate of larger fish based on an
analysis of data from Chinook Salmon tagged in 2012 that passed the Deshka River weir site.
These measures were not sufficient to eliminate sampling bias, but they likely reduced over-
sampling of small fish. Size-selective sampling was also detected for Coho Salmon radio-tagged
at the Lower River site in 2013 and 2014. And lastly, size selectivity was detected in the Yentna
River in 2014 for Chinook Salmon. No length data were available for the second sample event
in the Yentna drainage in 2013, so size selectivity could not be tested. Furthermore as described
above, for cases where size selectivity was detected, size-stratification provided minimally
biased estimates of abundance and distribution of spawning Chinook and Coho salmon.
In the Middle River, size selectivity could only be directly tested in one study year (2013) due to
difficulties in collecting a sufficient number of length samples on the spawning grounds. As a
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result, ancillary length-frequency comparisons (i.e., between capture sites, and between fish
captured and tagged), sonar data collected immediately below the Site 1 fishwheel, and expert
opinion were used to provide some insights into the potential for size selectivity in the Middle
River. In the first study year (2012), the study team conducted ground -based stream counts and
carcass surveys in the Indian River and Portage Creek to sample fish for mark rates and lengths.
Very few carcasses were found despite excellent survey conditions, which was likely due to
carcasses being removed from the rivers by predators. In 2013, the study team installed a picket
weir and underwater video system on the lower Indian River as a method of obtaining mark rates
and length data on the spawning grounds. Comparisons of cumulative length-frequency
distributions for large Chinook Salmon radio-tagged in the Middle River and those inspected and
recaptured at the weir showed no evidence of size-selective sampling. Too few radio-tagged fish
of the other salmon species were recaptured at the weir in 2013 to test for size selectivity. In
2014, the study team could not directly test for size-selective sampling because the Indian River
weir was rendered inoperable prior to the onset of the Chinook Salmon run and thus no length
samples were collected.
For small Chinook and Pink salmon, tagging efforts were not random at the Middle River
fishwheels in 2013 and 2014 as only the larger-sized segment of the small fish captured were
radio-tagged. This was due to the fact that the radio tags would simply not fit into the stomachs
of smaller-sized fish. For Pink Salmon, the difference in mean length between captured and
radio-tagged fish was less than 1.5 cm (0.6 in), and relatively few fish captured measured less
than 40 cm (15.7 in) METF, so it was unlikely that selecting for slightly larger-sized fish to tag
had a material effect on the study results. Small Chinook Salmon, however, comprised a
substantial portion of the total number of Chinook Salmon captured at the Middle River
fishwheels (23–35 percent in 2013 and 2014), yet only a fraction were radio-tagged (11 percent
or less). In 2014, the smallest radio-tagged Chinook Salmon measured 36 cm (14.2 in) METF,
yet 61 percent (121 of 198 fish) of small Chinook Salmon captured measured less than 36 cm
(14.2 in) METF. No radio-tagged small Chinook Salmon passed above Devils Canyon in the
three study years, so it was unlikely that any additional fish would have passed the impediments
had additional small Chinook Salmon been radio-tagged.
Additional information suggested size-selectivity did not introduce significant bias to study
results. Sonar data collected immediately downstream of the Site 1 fishwheel in the Middle
River suggested that very few fish migrated upstream at distances greater than 13 m (42.7 ft)
from the shore-based transducer, and that fish of all sizes seemed equally distributed at range
from shore. Sonar was not used at sites 2 or 3, however, the higher water velocities at these sites
suggested an even greater proportion of fish would be bank-oriented relative to Site 1. All size
classes of salmon were captured at each fishwheel, indicating that fish of all lengths had a non-
zero capture probability. And lastly, based on the experience of the study team, the Middle
River fishwheel sites were characterized as generally high gradient with moderate-to-high
offshore river velocities, which were similar features of fishwheel sites on other river systems
where the least size selectivity was encountered (Link and Nass 1999; Smith et al. 2005).
5.1.4. Examining Handling-Induced Changes in Behavior
Fish that were obviously affected by handling (those that moved only in a downstream direction,
and those that never moved) were not included in any of the behavioral analyses described in this
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report. Regardless, other fish may have also experienced handling-related changes in behavior.
One way to quantify handling-induced effects was to compare the survival and behavior of fish
that were handled twice (i.e., recaptured in fishwheels) to those of the general populations of
tagged fish, specifically, comparing the proportions tracked to spawning destinations.
Of the 590 large Chinook Salmon that were radio-tagged and released at the Middle River
fishwheels, 21 (3.6 percent) fish were recaptured at least once at the Middle River fishwheels, of
which two fish were recaptured a second time. Most of the large Chinook Salmon recaptured for
the first time were caught at the Site 3 fishwheel (14 fish), which was located the farthest
upstream, while the remainder were caught at the Site 1 (6 fish) and Site 2 (1 fish) fishwheels.
The elapsed time between tag and recapture events ranged from 14 minutes to 21 days (median =
4.1 days; n = 17). The fish recaptured 21 days after release was noted as a ‘post-spawn’ fish by
the crew. Of the 21 fish recaptured at least once, the radio tag was coded for 17 fish. Of these
17 recaptured fish, 53 percent were subsequently assigned spawning destinations (i.e., classified
into a specific tributary or mainstem spawning location); this percentage was low compared to
the overall rate of 80 percent (χ2 = 7.4; P < 0.01). Neither of the two fish recaptured twice were
assigned spawning destinations. The lower proportion of assigned destinations and relatively
long times between capture events suggested that the behavior of large Chinook Salmon handled
twice may have been negatively influenced by the recapture events, thus failing to dismiss the
possible impacts of the original capture event
Three (9.4 percent) of the 32 radio-tagged small Chinook Salmon released at the Middle River
fishwheels were recaptured (median time between capture events was 13.3 days; n = 3), all of
which were assigned spawning destinations, suggesting that the additional handling did not
substantially influence the behavior of these fish. The negligible impacts of second handling
events suggest that the original handling of these fish was benign.
Ten Pink, 8 Chum, 5 Coho, and 4 Sockeye salmon released at the Middle River fishwheels were
also recaptured. The radio tag was not coded upon recapture for one Chum and one Pink
salmon. Of the recaptured fish with known tag codes, the elapsed time between capture events
was longest for Sockeye (median = 1.4 days, n = 4), followed by Chum (median = 0.9 days, n =
7), Pink (median = 0.9 days, n = 9), and Coho (median = 0.8 days, n = 5) salmon. Seventy-one
percent of recaptured Chum Salmon were assigned spawning destinations, which was similar to
the overall rate of 80 percent (χ2 = 0.3; P = 0.60). All of the recaptured Pink, Sockeye, and Coho
salmon were assigned spawning destinations. The relatively short time period between capture
events and the large proportion of recaptured fish that were assigned spawning destinations
suggests the additional handling did not substantially influence the behavior of Chum, Coho,
Pink, or Sockeye salmon. Moreover, it was assumed that the short recapture period indicated the
fish had sufficiently recovered from the first handling event, having rejoined the migration of
untagged fish. The negligible impacts of second handling events suggest that the original
handling of these species was benign.
Another way to quantify handling-induced effects was to examine swim speeds in a given river
reach, comparing newly tagged fish to those that have had time to recover from handling. Few
fixed-station receivers monitored both Lower and Middle River frequencies, hence the best test
was to compare travel speeds of Lower-River-tagged fish from Sunshine to Lane to those of
Middle-River-tagged fish from release (near Curry) to Gateway. If the newly tagged fish were
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experiencing handling-induced effects, their travel speeds should have been slower than those of
nearby Lower-River-tagged fish. In all cases, the recently-handled Middle-River-tagged fish
travelled faster than the unhandled (Lower-River-tagged) conspecifics (Figure 5.1-3), with
effects being statistically significant for Coho Salmon (χ2 = 9.7, P = 0.0018; Chinook Salmon: χ2
= 0.8, P = 0.77; Pink Salmon: χ2 = 3.5, P = 0.061).
As a comparison among tagging sites of the relative magnitude of potential handling-induced
effects, the proportion of fish that either never left the release area or that moved only in a
downstream direction was examined. For large Chinook Salmon, the proportion was 4 percent at
the Lower River fishwheels, 10 percent at the Middle River fishwheels, and 19 percent in the
Yentna River. For Coho Salmon, the proportion was 1 percent at the Lower River fishwheels, 11
percent at the Middle River fishwheels, and 12 percent in the Yentna River. For Pink Salmon,
the proportion was 10 percent at the Lower River fishwheels, and 3 percent at the Middle River
fishwheels.
5.2. Objective 2: Determine the migration behavior and spawning
locations of radio-tagged fish in the Lower, Middle, and Upper
Susitna River
Migration behavior and spawning locations were relatively consistent among years. Of the fish
tagged in the Lower River that could be categorized to a destination, the majority (97–99 percent
of the large Chinook Salmon, 90 percent of the Chum Salmon, 93–97 percent of the Coho
Salmon, 84–99 percent of the Pink Salmon, and 100 percent of the Sockeye Salmon) had
tributary destinations, rather than mainstem ones. The Talkeetna, Yentna, Deshka, and Chulitna
rivers were the main tributary destinations. For the fish tagged in the Middle River a similar
pattern was observed, showing predominant use of tributaries for all species (tributaries were
used by 90–94 percent of the large Chinook Salmon, 83–93 percent of the small Chinook
Salmon, 76–90 percent of the Chum Salmon, 84–94 percent of the Coho Salmon, and 91–94
percent of the Pink Salmon) except Sockeye Salmon. Sockeye Salmon tagged in the Middle
River had the greatest tendency to have a mainstem destination (only 21–54 percent had tributary
destinations), which was markedly different behavior from their Lower River conspecifics, and
from all other salmon species. For fish tagged in the Middle River, Portage Creek and Indian
River were the main tributary destinations for all species (AEA 2013a, 2014c). Detailed results
related to the migration behavior and spawning locations of radio-tagged fish in 2014 are
presented below and in Appendices D and E. Destinations and potential spawning sites for
radio-tagged fish across years are shown in Figures D-1 to D-20.
5.2.1. Chinook Salmon
5.2.1.1. Fish tagged in Lower River
5.2.1.1.1. Tag Returns
Of the large Chinook Salmon radio tags deployed in the Lower River, 24 were recovered by
anglers (23 tags) or project field staff (1 tag; Table E-1). Large Chinook Salmon tags were
recovered in the Chulitna (1), Deshka (16), and Lower Susitna (1) rivers, as well as Clear (2),
Deception (1), Lake (1), Peter’s (1), and Sheep (1) creeks.
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5.2.1.1.2. Stock Classifications and Spawning and Holding Locations
Of the 656 large Chinook Salmon tagged in the Lower River, 581 (89 percent) were classified by
destination (Table 5.2-1). Of the remaining 75 tags, 44 were ignored (zero or one detection,
never moved from release site, or moved only in the downstream direction) and 31 exhibited
movements that prevented conclusive assignment to the mainstem or tributaries (see “Other
Classifications” in Table 5.2-1).
Of the 581 Chinook Salmon tracked to a destination, 7 (1 percent) went to destinations in the
mainstem Susitna River (Table 5.2-1; Figure 5.2-1). There were six potential spawning and
holding sites documented in the Lower River, including 3 within slough/side channel, 2 within
main channel, and 1 within tributary mouth habitats. There were no potential spawning sites
identified in the Middle River downstream or upstream of Devils Canyon, but there was one
potential mainstem spawning site within Devils Canyon, located at the mouth of Cheechako
Creek. Spawning was not confirmed at any of the potential spawning sites for Chinook Salmon.
Lack of confirmation was largely due to high turbidity precluding visual observation.
Of the 581 Chinook Salmon tracked to a destination, 574 (99 percent) went to tributaries. Of
these, 94.6 percent used Lower River tributaries, mainly the Yentna, Deshka, Talkeetna or
Chulitna rivers (Figure 5.2-2). The remaining 5.4 percent had tributary destinations in the
Middle River Segment below Devils Canyon, mainly in Indian River or Portage Creek. One fish
had a tributary destination above Impediment 1, in Cheechako Creek.
5.2.1.1.3. Roaming Behavior in the Middle River
Of the large Chinook Salmon tagged in the Lower River that entered the Middle River, 13.9
percent of the fish with known-classification subsequently moved downstream into a tributary
(Table 5.2-2). Roamers eventually went to either the Chulitna or Talkeetna rivers, or Montana
Creek. Some roaming fish moved far up into the Middle River before dropping back to enter
downstream tributaries (Table 5.2-3). For example, one Chinook Salmon tagged in Lower River
moved upstream to the area below Impediment 1 before dropping back to enter the Chulitna
River.
5.2.1.2. Fish Tagged in Yentna River
5.2.1.2.1. Tag Returns
Of the large Chinook Salmon radio tags deployed in the Yentna River, four were recovered by
anglers (Table E-1). Large Chinook Salmon tags were recovered in the Yentna at the mouth of
Lake Creek (2), or in Lake Creek itself (2).
5.2.1.2.2. Stock Classifications and Spawning Locations
Chinook Salmon radio-tagged in the Yentna River were expected to stay within this major
tributary, and significant movement to other Susitna River tributaries was not expected (relative
to Chinook Salmon tagged in the Lower River). As expected, 219 of the 295 Chinook Salmon
released in the Yentna River (74 percent) were classified with a Yentna destination, and 8
(3 percent) were classified in other Lower Susitna River tributaries (Little Willow and Willow
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creeks, or Deshka or Chulitna rivers; Table 5.2-1). Of the remaining 68 tags, 64 were ignored
(zero or one detection, never moved from release site, or moved only in the downstream
direction) and four exhibited movements that prevented conclusive assignment to the mainstem
or tributaries (see “Other Classifications” in Table 5.2-1).
5.2.1.2.3. Roaming Behavior in the Middle River
No fish tagged in the Yentna River migrated into the Middle River and subsequently moved
downstream into a tributary.
5.2.1.3. Fish Tagged in Middle River
5.2.1.3.1. Tag Returns
Of the large Chinook Salmon radio tags deployed in the Middle River, thirteen were recovered
by anglers (3 tags), project field staff (6 tags), or others (4 tags; Table E-2). Thirteen large
Chinook Salmon tags were recovered in the Indian (5) and Middle Susitna (Indian River
confluence; 1) rivers, at the mouth of Jack Long Creek (1), and at the Site 3 fishwheel (6).
5.2.1.3.2. Stock Classifications and Spawning Locations
Of the 590 large Chinook Salmon radio-tagged in the Middle River, 472 (80 percent) were
classified by spawning destination (Table 5.2-1). Of the remaining 118 tags, 58 were ignored
(zero or one detection, never moved from release site, or moved only in the downstream
direction) and 60 exhibited movements that prevented conclusive assignment to the mainstem or
tributaries (Table 5.2-1).
Of the 472 large Chinook Salmon tracked to a spawning and holding destination, 34 (7 percent)
went to mainstem destinations, all in the Middle River downstream of Devils Canyon (Table 5.2-
1; Figure 5.2-1; Table D-2), including 8 within slough/side channel, 4 within main channel, and
22 within tributary mouth habitats. The other 438 fish (93 percent) went to tributaries. Of these,
11 percent used Lower River tributaries (mainly Talkeetna or Chulitna rivers; Figure 5.2-3), 88.4
percent used tributaries in the Middle River below Devils Canyon (mainly Indian River or
Portage Creek; Figure 5.2-3), 2 fish (0.5 percent) used a tributary within the canyon (Cheechako
Creek), and 1 fish (0.2 percent) used an Upper River tributary (Kosina Creek).
In addition to the large Chinook Salmon described above, 32 small Chinook Salmon were radio-
tagged and released in the Middle River. For these small Chinook Salmon, 24 (75 percent) were
classified by destination (Table 5.2-1). Of the remaining 8 small Chinook Salmon tagged, 5
were ignored (never moved from release site, or moved only in the downstream direction) and 3
exhibited movements that prevented conclusive assignment to the mainstem or tributaries (see
“Other Classifications” in Table 5.2-1).
Of the 32 small Chinook Salmon tracked to a spawning destinations, 4 (17 percent) went to
destinations in the mainstem Middle River downstream from Devils Canyon (Table 5.2-1; Table
D-2; Figure 5.2-1): 3 were at the mouth of Indian River, and one was in a side channel habitat.
The other 20 fish (83 percent) went to tributaries Of these, 1 fish (5 percent) used a Lower River
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tributary (Talkeetna River; Figure 5.2-3), and the remaining 19 fish (95 percent) used tributaries
in the Middle River below Devils Canyon (mainly Indian River or Portage Creek; Figure 5.2-3).
Chinook Salmon (small and large) were tracked to 18 potential mainstem spawning and holding
sites in the Middle River between PRM 111.0 and PRM 155.9 (Table D-2). There were five sites
at which more than one radio-tagged Chinook Salmon was detected (#3, 10, 13, 15, 17). No
potential mainstem spawning sites for Chinook Salmon were identified above PRM 160. To
assess if there was spawning activity, all 18 sites were visually examined during aerial telemetry,
boat, or foot surveys (Habitat Suitability Criteria [HSC]; Table D-1); and turbid water precluded
visual confirmation of spawning activity at all sites. A DIDSON unit was used at six of the sites;
however the remaining 12 sites were not surveyed using sonar due to lack of boat access or
bathymetric features that were not conducive to sonar sampling. Holding behavior was observed
at one main channel (#10) and three tributary mouth habitats (#5, 13, 17), but no fish were
observed spawning at any of the 18 sites.
5.2.1.3.3. Roaming Behavior in the Middle River
Several fish tagged at the Curry fishwheels moved downstream into a Lower or Middle River
tributary (Table 5.2-2). For large Chinook Salmon tagged at the Curry fishwheels, 472 had
known classifications, of which 54 (11.4 percent) exhibited this roaming behavior. Most
roamers eventually went to either the Chulitna or Talkeetna rivers. Some roaming fish moved
far up into the Middle River before dropping back to enter downstream tributaries (Table 5.2-3).
For example, two Chinook Salmon tagged in Middle River moved upstream to the area below
Impediment 1 before dropping back to enter the Talkeetna River. For small Chinook Salmon
tagged at the Curry fishwheels, 24 had known classifications of which 5 (20.8 percent) exhibited
roaming behavior. The farthest upstream any of these fish reached was the Gateway site, and the
farthest downstream tributary was Talkeetna River.
5.2.2. Chum Salmon
5.2.2.1. Fish Tagged in Middle River
5.2.2.1.1. Tag Returns
Of the Chum Salmon radio tags deployed in the Middle River, one was recovered by field crew
at the mouth of 4th of July Creek (Table E-2).
5.2.2.1.2. Stock Classifications and Spawning Locations
Of the 200 Chum Salmon tagged in the Middle River, 159 (80 percent) were classified by
destination (Table 5.2-1). Of the remaining 41 tags, 10 were ignored (zero or one detection,
never moved from release site, or moved only in the downstream direction) and 31 exhibited
movements that prevented conclusive assignment to the mainstem or tributaries (Table 5.2-1).
Of the 159 Chum Salmon tracked to a spawning destination, 18 (11 percent) went to destinations
in the mainstem Middle River (Table 5.2-1; Table D-3; Figure 5.2-1), including 11 within
slough/side channel, 2 within main channel, and 5 within tributary mouth habitats. The other
141 (89 percent) went to tributaries. Of these, 30.5 percent used Lower River tributaries (mainly
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Talkeetna or Chulitna rivers; Figure 5.2-3), and 69.5 percent used tributaries in the Middle River
below Devils Canyon (mainly Indian River or Portage Creek; Figure 5.2-3).
Chum Salmon were tracked to 14 potential mainstem spawning and holding sites in the Middle
River between PRM 111.3 and PRM 155.9 (Table D-3). There were two sites at which more
than one radio-tagged Chum Salmon was detected (#7, 9). No potential mainstem spawning sites
for Chum Salmon were identified above PRM 152.3. To assess if there was spawning activity,
all 14 sites were visually examined during aerial telemetry, boat, or foot surveys. Eleven sites
were surveyed aerially (#1–6, 8, 10–14), and ten sites by boat/foot (#2, 5–13). No fish were
observed at three of the sites (#3, 4, 7; Table D-3). Six sites were too turbid to see fish during
aerial surveys (#1, 2, 6, 10, 11, 13) even though they were regularly monitored. Holding
behavior was observed at two slough/side channel (#5, 9) and three tributary mouth habitats (#8,
12, 14), while fish were observed spawning at two of the 14 sites (#5, 12). Both confirmed
spawning sites were also confirmed in 2012 and 2013.
5.2.2.1.3. Roaming Behavior in the Middle River
Several fish tagged at the Curry fishwheels moved downstream into a Lower or Middle River
tributary (Table 5.2-2). Of the classified Chum Salmon tagged at the Curry fishwheels, 28
percent returned to a downstream tributary. Chum Salmon roamed as far as the mouth of
Portage Creek before turning downstream. Most of the roamers eventually went to either the
Chulitna or Talkeetna rivers, and three went as far as Montana Creek.
5.2.3. Coho Salmon
5.2.3.1. Fish Tagged in Lower River
5.2.3.1.1. Tag Returns
Of the Coho Salmon radio tags deployed in the Lower River, 36 were recovered by anglers (35
tags) or project field staff (1 tags; Table E-1). Coho Salmon tags were recovered in the Deshka
(9), Kashwitna (2), Talachulitna (1), and Talkeetna (6) rivers; and Clear (4), Little Willow (1),
Montana (2), Rabideaux (2), Sheep (1), Sunshine (2), Trapper (2), Troublesome (1), Whiskers
(1), and Willow (2) creeks.
5.2.3.1.2. Stock Classifications and Spawning Locations
Of the 640 Coho Salmon tagged in the Lower River, 581 (91 percent) were classified by
destination (Table 5.2-1). Of the remaining 59 tags, 10 were ignored (zero or one detection,
never moved from release site, or moved only in the downstream direction) and 49 exhibited
movements that prevented conclusive assignment to the mainstem or tributaries (see “Other
Classifications” in Table 5.2-1).
Of the 581 Coho Salmon tracked to a destination, 16 (3 percent) went to destinations in the
mainstem Susitna River (Table 5.2-1; Figure 5.2-1). All sixteen potential spawning and holding
sites were in the Lower River. These sites included 13 slough/side channel and 3 tributary
mouth habitats. During the survey period, mainstem water clarity was ideal for visual
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confirmation of spawning activity; however, none of the potential spawning sites were confirmed
for spawning.
Of the 581 Coho Salmon tracked to a destination, 565 (97 percent) went to tributaries. Of these,
94.2 percent used Lower River tributaries, mainly the Yentna, Deshka, Talkeetna, or Chulitna
river (Figure 5.2-2). The remaining 5.8 percent had tributary destinations in Middle River
downstream from Devils Canyon, mainly in Whiskers Creek or Indian River.
5.2.3.1.3. Roaming Behavior in the Middle River
Of the Coho Salmon tagged in the Lower River that entered the Middle River, 40 percent of the
fish with known-classification subsequently moved downstream into a tributary (Table 5.2-2).
Most roamers eventually went to Chase or Whiskers creeks, or Chulitna River. Roaming fish
moved as far up into the Middle River as the mouth of Indian River before dropping back to
enter downstream tributaries (Table 5.2-3).
5.2.3.2. Fish Tagged in Yentna River
5.2.3.2.1. Tag Returns
Of the Coho Salmon radio tags deployed in the Yentna River, two were recovered (Table E-1),
both from Deshka River.
5.2.3.2.2. Stock Classifications and Spawning Locations
Coho Salmon radio-tagged in the Yentna River were expected to stay within this major tributary,
and significant movement to other Susitna River tributaries was not expected (relative to Coho
Salmon tagged in the Lower River). As expected, 43 of the 60 Coho Salmon released in the
Yentna River (72 percent) were classified with a Yentna destination, and 5 (8 percent) were
classified in other Lower Susitna River tributaries (Deshka or Chulitna rivers; Table 5.2-1). The
remaining 12 tags were ignored (zero or one detection, never moved from release site, or moved
only in the downstream direction; see “Other Classifications” in Table 5.2-1).
5.2.3.2.3. Roaming Behavior in the Middle River
No fish tagged in the Yentna River migrated into the Middle River and subsequently moved
downstream into a tributary.
5.2.3.3. Fish Tagged in Middle River
5.2.3.3.1. Tag Returns
Of the Coho Salmon radio tags deployed in the Middle River, two were recovered: one in the
Talkeetna River and one in Portage Creek (Table E-2).
5.2.3.3.2. Stock Classifications and Spawning Locations
Of the 230 Coho Salmon tagged in the Middle River, 184 (80 percent) were classified by
destination (Table 5.2-1). Of the remaining 46 tags, 26 were ignored (zero or one detection,
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never moved from release site, or moved only in the downstream direction) and 20 exhibited
movements that prevented conclusive assignment to the mainstem or tributaries (Table 5.2-1).
Of the 184 Coho Salmon tracked to a spawning destination, 11 (6 percent) went to mainstem
destinations: one in the Lower River (a side channel near the mouth of the Chulitna), and ten to
the Middle river (Table 5.2-1; Table D-4; Figure 5.2-1), including 5 within slough/side channel,
2 within main channel, and 3 within tributary mouth habitats. The other 173 fish (94 percent)
went to tributaries. Of these, 15 percent used Lower River tributaries (mainly Talkeetna River;
Figure 5.2-3), and 85 percent used tributaries in the Middle River downstream from Devils
Canyon (mainly Indian River or Portage Creek; Figure 5.2-3).
Coho Salmon were tracked to eight potential mainstem spawning and holding sites in the Middle
River between PRM 111.3 and PRM 155.9 (Table D-4). There were two sites at which more
than one radio-tagged Coho Salmon was detected (#3, 6). No potential mainstem spawning and
holding sites for Coho Salmon were identified above PRM 152.3. To assess if there was
spawning activity, seven sites were visually examined during aerial telemetry, boat, or foot
surveys (HSC). Seven sites were surveyed aerially (#1–6, 8), and two sites by boat/foot (#2, 7).
No fish were observed at five of the sites (#3-7; Table D-4). Two sites were too turbid to see
fish during aerial surveys (#1, 2) even though they were regularly monitored. Holding behavior
was observed at one tributary mouth habitat (#8), but no fish were observed spawning at any of
the eight sites (despite ideal water clarity for visual inspection).
5.2.3.3.3. Roaming Behavior in the Middle River
Several fish tagged at the Curry fishwheels moved downstream into a Lower or Middle River
tributary (Table 5.2-2). For Coho Salmon tagged at the Curry fishwheels, 29 percent of the
classified fish exhibited this roaming behavior. Middle River Coho Salmon roamed as far as the
mouth of Portage Creek before turning downstream, and one fish moved far enough downstream
to enter Yenta River.
5.2.4. Pink Salmon
5.2.4.1. Fish Tagged in Lower River
5.2.4.1.1. Tag Returns
Of the Pink Salmon radio tags deployed in the Lower River, two were recovered (Table E-1):
one from Willow Creek and one from Montana Creek.
5.2.4.1.2. Stock Classifications and Spawning Locations
Of the 199 Pink Salmon tagged in the Lower River, 156 (78 percent) were classified by
destination (Table 5.2-1). Of the remaining 43 tags, 20 were ignored (never moved from release
site) and 22 exhibited movements that prevented conclusive assignment to the mainstem or
tributaries (see “Other Classifications” in Table 5.2-1).
Of the 156 Pink Salmon tracked to a destination, only 1 fish (< 1 percent) was classified as
having a destination in the mainstem Susitna River (Table 5.2-1; Figure 5.2-1). It was a main
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channel site in the Lower River. Spawning was not confirmed at this location due to high
turbidity precluding visual observation.
Of the 156 Pink Salmon tracked to a destination, 155 (~99 percent) went to tributaries. Of these,
97.4 percent used Lower River tributaries, mainly the Yenta, Deshka or Chulitna rivers, or
Willow Creek (Figure 5.2-2). The remaining 2.6 percent (4 fish) had tributary destinations in
Middle River below Devils Canyon, specifically, in 4th of July Creek or Indian River.
5.2.4.1.3. Roaming Behavior in the Middle River
Of the Pink Salmon tagged in the Lower River that entered the Middle River, 33 percent of the
fish with known-classification subsequently moved downstream into a tributary, either to the
Talkeetna or Chulitna rivers. These Pink Salmon roamed as far as the mouth of Portage Creek
before turning downstream.
5.2.4.2. Fish Tagged in Middle River
5.2.4.2.1. Tag Returns
Of the Pink Salmon radio tags deployed in the Middle River, two were recovered: one in 4th of
July Creek, and one at the Montana Creek weir (Table E-2).
5.2.4.2.2. Stock Classifications and Spawning Locations
Of the 201 Pink Salmon tagged in the Middle River, 176 (88 percent) were classified by
destination (Table 5.2-1). Of the remaining 25 tags, 8 were ignored (zero or one detection, never
moved from release site, or moved only in the downstream direction) and 17 exhibited
movements that prevented conclusive assignment to the mainstem or tributaries (Table 5.2-1).
Of the 176 Pink Salmon tracked to a spawning destination, 12 (7 percent) went to destinations in
the mainstem Middle River (Table 5.2-1; Table D-5; Figure 5.2-1), including 5 with slough/side
channel, and 7 with tributary mouth habitats. The other 164 fish (93 percent) went to tributaries.
Of these, 23.9 percent used Lower River tributaries (mainly Talkeetna or Chulitna rivers; Figure
5.2-3), and 67.1 percent used tributaries in the Middle River downstream from Devils Canyon
(mainly 4th of July Creek or Indian River; Figure 5.2-3).
Pink Salmon were tracked to eight potential mainstem spawning and holding sites in the Middle
River between PRM 111.3 and PRM 155.9 (Table D-5). There were three sites at which more
than one radio-tagged Pink Salmon was detected (#1, 3, 7). No potential mainstem spawning
and holding sites for Pink Salmon were identified above PRM 148. To assess if there was
spawning activity, all eight sites were visually examined during aerial telemetry, boat, or foot
surveys (HSC). Four sites were surveyed aerially (#1, 5, 6, 8), and four sites by boat/foot (#1, 5,
6, 8). No fish were observed at two of the sites (#2, 4). Three sites were too turbid to see fish
during aerial surveys (#5, 6, 8) even though they were regularly monitored. Holding behavior
was observed at two tributary mouth habitats (#3, 7), but no fish were observed spawning at any
of the 8 sites (despite that water clarity was ideal for visual inspection). The two potential
spawning sites that Pink Salmon were observed holding in 2014 had been spawning locations in
at least one of the previous years (2012 and 2013).
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5.2.4.2.3. Roaming Behavior in the Middle River
Several fish tagged at the Curry fishwheels moved downstream into a Lower or Middle River
tributary (Table 5.2-2). For Pink Salmon tagged at the Middle River fishwheels, 39 percent of
the classified fish exhibited this roaming behavior. Most of the roamers eventually went to either
to Talkeetna River, Whiskers Creek or Chulitna River, although one fish moved far enough
downstream to enter the Yenta River. Most Middle River Pink Salmon roamed as far upstream
as the mouth of Indian River, others reached the mouth of Portage Creek, before turning
downstream.
5.2.5. Sockeye Salmon
5.2.5.1. Fish Tagged in Middle River
5.2.5.1.1. Tag Returns
Of the Sockeye Salmon radio tags deployed in the Middle River, five were recovered (Table E-2)
in the Middle Susitna River (PRM 141 and 145; 2); as well as in Chase (1), Disappointment (1),
and Larson (1) creeks.
5.2.5.1.2. Stock Classifications and Spawning Locations
Of the 200 Sockeye Salmon tagged in the Middle River, 142 (71 percent) were classified by
destination (Table 5.2-1). Of the remaining 58 tags, 9 were ignored (never moved from release
site, or moved only in the downstream direction) and 49 exhibited movements that prevented
conclusive assignment to the mainstem or tributaries (Table 5.2-1).
Of the 142 Sockeye Salmon tracked to a spawning destination, 66 (46 percent) went to
destinations in the mainstem Middle River (Table 5.2-1; Table D-6; Figure 5.2-1), all in
slough/side channel habitats. The other 76 fish (54 percent) went to tributaries. Of these, 82.2
percent used Lower River tributaries (mainly Talkeetna or Chulitna rivers; Figure 5.2-3), and
11.8 percent used tributaries in the Middle River downstream from Devils Canyon (mainly
Indian River or Portage Creek; Figure 5.2-3).
Sockeye Salmon were tracked to eight potential mainstem spawning and holding sites in the
Middle River between PRM 111.3 and PRM 155.9 (Table D-6). At seven of the eight sites,
more than one radio-tagged Sockeye Salmon was detected (#2–8). No potential mainstem
spawning sites for Sockeye Salmon were identified above PRM 146. To assess if there was
spawning activity, all eight sites were visually examined during aerial telemetry, boat, or foot
surveys (HSC). Four sites were surveyed aerially (#1, 2, 6, 7) and seven sites by boat/foot (#2–
8). No fish were observed at three of the sites (#1, 3, 4). Holding and spawning behavior was
observed at five sites (#2, 5–8). All confirmed spawning sites were also confirmed in 2012 and
2013.
5.2.5.1.3. Roaming Behavior in the Middle River
Sockeye Salmon tagged at the Curry fishwheels were the most likely species to roam (Table
5.2-2): 49 percent of the classified Sockeye Salmon did so. These Sockeye Salmon moved far up
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into the Middle River before dropping back to enter downstream tributaries. For example, three
Sockeye Salmon moved upstream to Impediment 1 (two above and one below) before dropping
back. Middle River Sockeye Salmon moved downstream to a variety of Lower River locations.
Most of the roamers eventually went to either the Chulitna or Talkeetna rivers, but one moved
far enough downstream to enter the Deshka River.
5.3. Objective 3: Characterize adult salmon migration behavior and
timing within and above Devils Canyon
5.3.1. Chinook Salmon
From 2012 to 2014, 17 large Chinook Salmon passed three impediments into the area above
Devils Canyon (12 fish in 2012, 3 in 2013, and 2 in 2014; Table F-1). Of these, seven had final
destinations that were above the proposed dam site, all in the Kosina Creek watershed (6 in 2012,
1 in 2014). A further three fish had destinations that were upstream of Devils Canyon but
downstream of Watana (2 in Devil Creek and 1 in Tsusena Creek). Detailed results related to
adult salmon migration behavior and timing within and above Devils Canyon in 2014 are
presented below (see Tables 5.3-1 and 5.3-2) and in Appendices F and G.
Of the 590 radio-tagged large Chinook Salmon tagged and released at the Middle River
fishwheels in 2014, 491 were detected at or above Gateway Station (PRM 130.1) after tagging
(Table 5.3-1). Of these 491 fish, 11 (2.2 percent) were tracked above Impediment 1 (PRM
155.2), 8 (1.6 percent) above Impediment 2 (PRM 160.2), and 2 (0.4 percent) above Impediment
3 (PRM 164.8). Thirty-four of the 656 large Chinook Salmon radio-tagged and released at the
Lower River fishwheels were detected above Gateway Station, of which two were tracked above
Impediment 1; one of which subsequently passed Impediment 2 (Tables 5.3-1 and 5.3-2; Figure
5.3-1). In addition, 32 radio-tagged small Chinook Salmon were tagged and released at the
Middle River fishwheels. Of these, 24 were detected above Gateway Station after tagging and
none passed Impediment 1 (Table 5.3-2; Figure 5.3-2).
5.3.1.1. Size of Chinook Salmon Tracked In and Above Devils Canyon
In 2014, 38 radio-tagged Chinook Salmon passed and/or approached to within 1 km (0.6 mi)
downstream of Impediment 1 (6 tagged in Lower River, 32 tagged in Middle River). The mean
length of these fish (78.9 cm [31.1 in]) was significantly larger than that of radio-tagged fish
which did not approach Impediment 1 (71.9 cm [28.3 in]; t522 = 3.10, P = 0.002). However,
there was not a significant difference in length between fish that passed Impediment 1 (77.3 cm
[30.4 in]) versus those that approached to within 1 km (0.6 mi) downstream of the Impediment
(79.7 cm [31.4 in]); Table 5.3-1; t36 = 0.53, P = 0.60). The mean length of fish that approached,
but did not pass Impediment 3 (79.0 cm [31.1 in], n = 4) was similar to that of fish that passed
Impediment 3 (n = 2; Table 5.3-1). These observations suggest that length may have been a
factor in approaching to within 1 km (0.6 mi) downstream of Impediment 1 for Chinook Salmon,
but was not a factor in successful passing of the impediments (although sample sizes for
statistical assessment of Impediment 3 passage were small).
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5.3.1.2. Behavior of Chinook Salmon At Devils Canyon
Fish showed noticeable milling or holding behavior below Impediment 1 and Impediment 3.
Fish that moved past Impediment 1 held below it for an average of 3.9 days; similar in duration
to individuals that did not pass (average 4.5 days; Table D-7). Four fish that passed
Impediment 1 did not attempt to pass Impediment 2; rather they moved into Cheechako Creek,
backed downstream to Portage Creek, or dropped downstream and died. All of the fish that
approached Impediment 2 passed it quickly (≤ 1 day; Table D-7). Three fish that passed
Impediment 2 did not attempt to pass Impediment 3; rather, they explored the area around
Chinook Creek, and eventually dropped back downstream. When considering patterns for the
six fish that approached Impediment 3, the hold times were shorter and approach dates were later
for the fish that passed as compared with those that did not pass. The two fish that passed
Impediment 3 held below it for an average of 6.8 days, whereas those that did not pass, held for
an average of 11.3 days before moving downstream (Figure 5.3-3). The two fish that passed
approached on or after July 30, where approach dates of the non-passing fish ranged from July 2
to 28.
The destination for the 13 Chinook Salmon tracked above Impediment 1 are provided in Table
5.3-3. Three of four Chinook Salmon that did not pass Impediment 2 could be conclusively
assigned to a spawning destination, with one (33 percent) of those being downstream of
Impediment 1. Three of seven Chinook Salmon that did not pass Impediment 3 could be
conclusively assigned to a spawning destination, and all 3 (100 percent) had a destination
downstream of Impediment 2. Overall, seven of the 13 Chinook Salmon that passed at least one
of the three impediments could be conclusively assigned to a spawning destination; and 4 of 7
destinations (57 percent) were downstream of the last impediment passed – two of these went to
Portage Creek, one to Cheechako Creek, and one to the mainstem near the mouth of Cheechako
Creek.
5.3.1.3. Passage Timing and Flows
In 2014, the first Chinook Salmon to successfully pass Impediment 1 passed on June 30 when
flow at the Tsusena Creek gauge was 19,400 cfs (26,000 cfs at the Gold Creek gauge; Figure
5.3-1). Other fish passed Impediment 1 on July 1 and July 6, during flows of 23,200 cfs or
greater at the Tsusena Creek gauge (27,900 cfs or greater at the Gold Creek gauge). No other
fish passed Impediment 1 until the period from July 18 to August 1, when Tsusena Creek gauge
flows ranged between 15,500 and 23,400 cfs (18,800–27,100 cfs at the Gold Creek gauge).
There was a period from July 7 to July 17 during which no fish passed, and flows ranged from
19,900 to 35,300 cfs at the Tsusena Creek gauge (24,200–36,500 at the Gold Creek gauge; Table
5.3-1; Figure 5.3-1). Both Chinook Salmon that later passed Impediment 3, had passed
Impediment 1 on the same day (July 20; Table D-7). Discharge when the two fish passed
Impediment 3 ranged from 15,900 cfs (July 30) to 16,400 cfs (August 4) at the Tsusena Creek
gauge (19,200–19,400 cfs at the Gold Creek gauge).
5.3.1.4. Behavior Upstream of Devils Canyon
Two Chinook Salmon passed Impediment 3, each showing markedly different behaviors (Figures
F-1 and F-2). One Chinook Salmon just barely passed Impediment 3, subsequently returned
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downstream of it, and eventually died in the mainstem downstream of Devils Canyon (Figure F-
1). The other Chinook Salmon travelled directly into Kosina Creek, spent 6 days therein, then
took 5 days to swim to and return from Oshetna River (40 km [25 mi] each way), before
returning to Kosina Creek (Figure F-2). This latter fish stayed in Kosina Creek for another 6
days, and then drifted out, settling just downstream of the mouth of Fog Creek.
5.3.1.5. Programmatic Summary
There was not strong or consistent evidence to suggest that body length influenced passage
success through Devils Canyon. In 2012, Chinook Salmon that passed Impediments 1 and 3
were larger on average than those than dropped back, but the differences were not statistically
significant (AEA 2013a). In 2013 and 2014, Chinook Salmon that passed the impediments were
slightly smaller on average than those that dropped back, and again the differences were not
statistically significant (AEA 2014c). In 2014, the Chinook Salmon that approached Devils
Canyon were significantly larger on average than the fish that never came within 1 km of
Impediment 1, but in 2012 and 2013 the same pattern was not observed. For large Chinook
Salmon tagged at the Middle River fishwheels in 2012 and 2014, the mean length of fish that
passed Impediment 3 was longer than that of the rest of the population (samples sizes were too
small for rigorous statistical analysis), yet the pattern was opposite in 2013 (unpublished data).
Overall, Chinook Salmon that ascended the impediments were at least 61 cm METF, but
Sockeye Salmon that passed Impediment 1 ranged from 45–49 cm METF. Given the
inconsistent results, it remains uncertain whether length is an important factor in successful
passage above the impediments.
In 2012, there were results to suggest that river flow rates influenced passage success through
Devils Canyon (AEA 2013a). In 2013, results similarly suggested that Impediment 3 passage
occurred only when Susitna River flows were lower than 19,000 cfs near Tsusena Creek (20,000
cfs at the Gold Creek gauge). In 2014, fish passage at Impediment 3 occurred only during
periods in which flow at the Tsusena Creek gauge dropped below 16,500 cfs (19,500 cfs at the
Gold Creek gauge). In all years, results were limited in sample size, and were not part of a
formal control-treatment experiment. Therefore, the degree to which lower flows played a
primary causal role in the passage of Chinook Salmon is not quantifiable. Of particular concern
is the potential confounding effects of “time of year.” Since, in all years, fish moved above the
final impediment during lower-flow periods that occurred at around the same timeframe (July
17–20 in 2012; July 13–30 in 2013; July 30 to August 4 in 2014), it is not possible to separate
out the relative importance of flows versus time of year.
Adult salmon migration behavior and timing within and above Devils Canyon has several
consistent characteristics. As we currently understand it, only large Chinook Salmon
(METF ≥ 50 cm [19.7 in]) regularly move upstream of Devils Canyon. Individuals that move
upstream of the canyon are not significantly different in size than other large Chinook Salmon.
Passage generally occurs in mid or late July. Passage events have not been observed during the
highest flow conditions (Table 5.3-1, Figure 5.3-1), yet specific flows that may trigger canyon-
passage behaviors were not evident from the data, other than that many occurred near the 10%
exceedance level.
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The main spawning destination in the Upper River is Kosina Creek, where peak counts have
ranged from 26 July to 5 August (Table 5.3-4; Figure 5.3-4; i.e., more than 2 weeks after the
radio-tagged fish were observed passing Impediment 3). Middle River spawning destinations
that are upstream of Devils Canyon and downstream of the dam site include Tsusena, Fog and
Devil creeks, where peak counts have ranged from 21 July (in Fog Creek in 1984) to 15 August
(in Fog Creek in 2013; Table 5.3-5; i.e., 2-4 weeks after radio-tagged fish were observed passing
Impediment 3). Within the canyon, Chinook Salmon spawn in Cheechako and Chinook creeks,
where peaks counts have generally been in late July or early August, although the peak count in
1985 was quite late (23 August in Chinook Creek; Table 5.3-5). Small Chinook (METF < 50 cm
[19.7 in]) and Sockeye salmon have successfully passed Impediment 1, but have always returned
downstream shortly thereafter without passing Impediment 2.
5.3.1.6. Aerial Spawner Surveys
Chinook Salmon was the only salmon species observed during aerial spawner surveys that were
flown from Cheechako Creek upstream to the Oshetna River in 2014. Adult Chinook Salmon
were observed in Middle River tributaries between Impediments 1 and 2 (Cheechako Creek),
between Impediments 2 and 3 (Chinook Creek), and above Impediment 3 (Devil and Fog
creeks). No adult salmon were observed in the mainstem Susitna River or in any Upper River
tributaries in 2014 (Table D-8).
In streams where they were observed, adult Chinook Salmon were not consistently seen over the
course of the season. They were documented in one stream during Survey 1, two streams during
Surveys 2 and 3, four streams during Surveys 4 and 5, one stream during Survey 6, and two
streams during Survey 7 (Table D-8). Peak observations occurred on July 19 in Cheechako and
Chinook creeks, July 31 in Fog Creek, and August 6 in Devil Creek.
In Cheechako Creek, the number of Chinook Salmon observed increased from 11 fish on July 14
to 16 fish on July 19. A steady decline in fish numbers was observed following July 31, and by
the final survey on August 18, zero fish were seen. Chinook Creek followed a similar trend with
five fish observed during the July 19 and July 25 surveys, two fish on the July 31 and August 6
surveys, and zero fish observed on the last two surveys.
Cheechako Creek is located between Impediment 1 and Impediment 2. It has high-gradient,
step-pools within steep-walled canyons. Chinook Salmon habitat terminates within three miles
of the Susitna River confluence at large waterfalls. The turbulent water and confined canyon
walls presented challenges to salmon observation. Nevertheless, salmon were observed
throughout this lower 3-mile reach of this creek, and groups of fish were seen holding in pools.
In Cheechako Creek, a no-fly zone around a raptor nest within the canyon prevented aerial
observation of approximately 0.5 miles of stream during the first two surveys.
Chinook Creek is located between Impediment 2 and Impediment 3. Chinook Creek has long
stretches of high-gradient cascades, but it does not have a barrier to Chinook Salmon migration
below 3,000 ft in elevation where the surveys terminated (at approximately tributary river mile
9). Regardless, fish were not seen beyond 0.5 miles upstream of the Chinook Creek confluence
with the Susitna River.
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Devil Creek is located just upstream of Devils Canyon. Devil Creek has similar geomorphology
to Cheechako Creek, featuring high-gradient, step-pools within steep-walled canyons. Chinook
Salmon habitat terminates within three miles of the Susitna River confluence at large impassable
waterfalls. The turbulent water and confined canyon walls presented challenges to salmon
observation. Nevertheless, fish were observed throughout the anadromous reach of this creek,
and groups of fish were seen holding in pools.
Low numbers of adult Chinook Salmon were observed in Fog Creek. The lower reach of Fog
Creek, where all the Chinook Salmon were observed, is dominated by high-gradient riffle
confined within a steep-walled canyon. The upper reach is much lower gradient and has long
stretches of gravel and cobble substrate that appeared suitable for Chinook Salmon spawning.
An additional five miles of a tributary to Fog Creek was also surveyed. Three adult Chinook
Salmon were observed in Fog Creek during Survey 4 on July 31; two fish were seen on Survey
5; zero on survey 6; and then one fish was observed during the final survey on August 18. The
farthest upstream observation was approximately three miles from the Fog Creek confluence
with the Susitna River.
Overall, weather conditions were favorable for observation throughout the study duration. While
weather was variable, it was not a limiting factor in observing fish and did not delay survey
completion (Table D-9). Low clouds and rain were the most influential weather factors; low
light conditions occasionally reduced visibility into the deeper water and rain on the aircraft
windows sometimes created difficult viewing conditions. Sun glare on the water was not a major
factor in limiting fish observations; polarized glasses, helicopter orientation, and survey direction
(some streams were surveyed from upstream to downstream) worked to improve visibility when
glare was present. Tall trees and overhanging vegetation partially obscured some areas of most
streams (Table D-10).
Overall, most streams had very clear water. The Black and Oshetna rivers were the only streams
of glacial origin within the study area and turbidity severely limited visibility in the Black River
and the Oshetna River downstream of the Black River confluence during all surveys. Visibility
in Watana and Jay creeks was typically poor in the lower few miles due to erosion produced
from landslides; whereas upstream of the landslides the water was clear. Kosina Creek
experienced several minor erosion events upstream of the study area which reduced visibility
slightly. The most prevalent impairment to seeing fish was white-water turbulence, which was
significant within all streams surveyed; white water was noted as limiting the observer’s ability
to find fish during all surveys (Table D-10).
5.3.1.7. Using Sonar to Enumerate Salmon at the Proposed Dam Site
Detailed results pertaining to 2014 field activities are provided in Appendix G, and a brief
summary is provided here.
During sonar operations from July 6 to August 22 at the proposed dam site, a total net-upstream
count of 24 Chinook Salmon was estimated based on the number of fish measuring 50 cm (19.7
in) TL or greater. Passage of these fish at Watana was observed from July 10 through August
22, and compared well with the passage of radio-tags at Impediment 3 on July 20. Aerial
spawner surveys were conducted between July 14 and August 19, so multiple forms of
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monitoring were occurring in the region over the same time period. The sonar array covered
approximately 58 percent of the channel width where the substrate was in the field of view and
water velocities outside the sonar range were too high (greater than 1.8 m/s [6 ft/s]) to be a
primary migration corridor. All observations of fish were within 4 m (13.1 ft) of the transducers
with most occurring at 3 m (9.8 ft). No apparent diel passage patterns were observed. Size
estimates for upstream migrants ranged from 50 to 110 cm (19.7–43.3 in) TL, with an average of
78 cm (30.7 in) TL. In addition, 213 fish measuring 40–49 cm (15.7-19.3 in) TL, and 1,044 fish
measuring less than 40 cm (15.7 in) TL, were counted at the sonar stations. Assuming the length
distribution of Chinook Salmon at Watana was the same as that at the Middle River fishwheels,
then an estimated 24.1 percent of Chinook Salmon at Watana were less than 50 cm (19.7 in).
This percentage would be a conservative estimate based on the length analysis presented in
Section 5.3.1.1 that demonstrated bigger fish were the ones approaching the impediments in
Devils Canyon. Even so, applying this conservative estimate to the sonar data, 24 Chinook
Salmon at Watana (targets ≥ 50 cm [19.7 in]) then represent 75.9 percent of the Chinook Salmon
that passed, and 8 additional Chinook Salmon measuring less than 50 cm (19.7 in) could have
passed (= 24 * 24.1 / 75.9). Note however, based on radio telemetry, no tagged Chinook Salmon
measuring less than 50 cm (19.7 in) METF have passed Impediment 3 in three seasons of study.
Considering all available information, it was estimated that greater than 90 percent of Chinook
Salmon migrating past Watana were observed by the sonar, or that about an additional 3 passage
events could have occurred.
5.3.2. Sockeye Salmon
Of the 200 radio-tagged Sockeye Salmon released at the Middle River fishwheels, 146 were
detected at or above Gateway Station (PRM 130.1; Table 5.3-1). Of these 146 fish, 3 (2.1
percent) were tracked above Impediment 1 (Tables 5.3-1 and 5.3-2; Figure 5.3-2). From 2012 –
2014, a total of 409 Sockeye Salmon were radio-tagged in the Middle River, and of these, 3 were
tracked above Impediment 1 (i.e., no Sockeye Salmon passed Impediment 1 in 2012 or 2013).
5.3.2.1. Size of Sockeye Salmon Tracked At Devils Canyon
Sixteen radio-tagged Sockeye Salmon passed and/or approached to within 1 km (0.6 mi)
downstream of Impediment 1. The mean length of these fish (48.5 cm [19.1 in]) was not
significantly different from that of fish that did not approach Impediment 1 (50.8 cm [20.0 in];
t144 = 1.7, P = 0.09). The mean body length of fish that approached, but did not pass Impediment
1 (48.8 cm [19.2 in]) was not significantly different from that of fish that passed Impediment 1
(47.3 cm [18.6 in]; Table 5.3-1; t14 = 0.44, P = 0.66). These observations indicate length was not
a factor in determining approach or successful passage of Impediment 1 for Sockeye Salmon
(although sample sizes for statistical assessment of impediment passage were small).
5.3.2.2. Behavior of Sockeye Salmon At Devils Canyon
The first Sockeye Salmon to successfully pass Impediment 1 passed on July 27 (Table D-7)
when flow at the Tsusena Creek gauge was 18,900 cfs (Figure 5.3-2; 23,900 cfs at the Gold
Creek gauge). No other Sockeye Salmon passed Impediment 1 until September 8, when two fish
were detected just above Impediment 1, but which returned downstream by the next day. From
July 27 to September 10, flows were relatively stable, averaging 15,600 cfs and ranging from
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12,900 to 18,900 cfs at the Tsusena Creek gauge (Figure 5.3-2; at Gold Creek gauge, flows
averaged 18,972, and ranged from 16,200 to 23,900 cfs). Sockeye Salmon that moved past
Impediment 1 held downstream for an average of 1.5 days before passing upstream; this is a
shorter holding time than for individuals that did not pass (average 4.7 days; Table D-7). None
of the three Sockeye Salmon that passed Impediment 1 approached Impediment 2.
All three of the Sockeye that passed Impediment 1 were later tracked to spawning destinations
that were downstream of the impediment: two went to the Chulitna River, and one to Jack Long
Creek.
5.3.2.3. Aerial Spawner Surveys
No adult Sockeye Salmon, nor Chinook Salmon, were observed during 2014 aerial surveys of the
two lakes in the Tsisi Creek drainage. Surveys were conducted approximately two weeks after
the timing of documented salmon passage above the Devils Canyon impediments and thus were
consistent with the timing of salmon presence in the Upper River. In addition, opportunistic fish
sampling was conducted in one of these lakes in late August and September and demonstrated
the presence of Lake Trout in the size range of 372-456 mm fork length (R2 Resource
Consultants 2015).
5.3.3. Other Species
No salmon species other than Chinook and Sockeye salmon were detected within Devils Canyon
in any of the three recent years of telemetry study and only Chinook Salmon were documented
above Impediment 3 of the canyon (AEA 2013a, 2014c).
5.4. Objective 4: Use available technology to document salmon
spawning locations in turbid water
Radio telemetry surveys were used to locate potential spawning locations for Chinook Salmon in
turbid water habitats of the Middle River from 2012–2014. In total, radio telemetry identified 98
radio-tagged Chinook Salmon suspected of spawning within turbid mainstem habitats of the
Middle River. The locations of these Chinook Salmon led ground crews to sample 44 potential
spawning areas, of which 18 were sampled using sonar technologies (side-scan, DIDSON, and
ARIS). Seven of the 44 potential spawning locations were repeat locations in at least two of the
three sampling years (2012-2014). Of the 18 locations sampled with sonar over the three study
years (sampling dates ranged from July 19 to July 31), Chinook Salmon spawning activity (i.e.,
nest-guarding behavior) was observed at one location in the mainstem Susitna River: near the
mouth of the Indian River (Table 5.4-1). At four turbid water locations (4th of July Creek Mouth,
Portage Creek Mouth, and two main channel habitats), Chinook Salmon were present or holding,
but exhibited no behavior indicative of spawning. The remaining 26 locations were either not
accessible by boat, were not suitable as spawning habitat, or did not contain Chinook Salmon
when viewed with sonar. Additionally, Chinook Salmon spawning behavior was confirmed
using sonar at the mouth of Jack Long Creek (2014); however, this location was not identified by
radio telemetry analysis. During the latter part of the Chinook Salmon migration in early
August, the presence of Chum Salmon at some locations made confirmation of Chinook Salmon
difficult.
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Spawning activity was not confirmed for any other salmon species using sonar technology. The
utility of using sonar to document spawning in turbid water was limited for several reasons.
First, Chum, Coho, Pink, and Sockeye salmon have a complete overlap in body size and run
timing making confirmation of species in turbid water using sonar impossible. Finally, due to
bathymetry and substrate size at many locations sonar imagery was not effective for detecting
features indicative of redds. Similarly, due to the slope of the river bed, redd digging behavior
could not be captured despite collecting several hours of imagery containing Chinook Salmon
and other salmon species in areas considered suitable for spawning. Worthy of mention, sonar
was able to confirm spawning behavior for a species of salmon at 4th of July Side Channel;
however, species ID was not able to be confirmed until water clarity increased later in the season
allowing visual confirmation of species.
5.4.1. Programmatic Summary
Over the three-year period, several limitations of the sonar method were identified. Redd
depressions were often difficult to observe in sonar imagery because of the slope of the river bed
or size of the substrate relative to the orientation of the redd depression. Tiffan et al. (2004)
found that DIDSON was more effective when Chinook Salmon redds exhibited sufficient
morphology (i.e., well-developed tailspills) and where the topography of the river bed was
somewhat smooth so that redds would not be confused with other bottom features. When a fish
swam into a redd depression (e.g., to dig), it could not be detected by the sonar. Given proper
orientation, fish could be observed on the sonar holding, swimming in and out of areas
considered to be redds, and displaying nest-guarding behavior. However, when a fish was not
oriented perpendicular to the sonar beam its acoustic signal became weak which made
identifying behavioral observations difficult. At times when multiple fish species with a large
degree of overlap in body length could be present (e.g., Chinook/Chum or
Chum/Coho/Pink/Sockeye), sonar was not able to positively identify species. This was less of an
issue for Chinook Salmon which spawned in part during a period when few other species were
present, and because they are typically much larger than most other salmon species. And lastly,
the equipment needed to operate a sonar was heavy and required a boat with a suitable gunnel-
mount. Many of the potential spawning locations were in side channels or sloughs that were too
shallow for the boat, so this limited the number of sites that could be sampled using the
equipment. Still, the study team successfully met this objective by demonstrating that sonar
technologies could be used to document spawning behaviors, but that the utility was limited,
given the current state of the technology, by bed topography and shallow depths at which salmon
spawn.
5.5. Objective 6: Generate counts of adult Chinook Salmon
spawning in the Susitna River and its tributaries
In July 2012, stream walks (visual counts) and aerial-tracking surveys proved to be ineffective
for generating counts and establishing mark rates in sections of the Indian River and Portage
Creek due to bear predation on Chinook Salmon. Thus, no escapement estimates for Chinook
Salmon above Devils Canyon were made in 2012. In 2013, a weir and underwater video system
were used to estimate an escapement of 1,137 large Chinook Salmon (mark rate of 6.3 percent)
to the Indian River. These data were used to estimate escapements of 6,952 large Chinook
Salmon above Gateway, and 48 large Chinook Salmon migrated above Devils Canyon in 2013.
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In 2014, the Indian River weir was rendered inoperable due to a flood so the study team used the
AUC method to estimate an escapement of 1,297 large Chinook Salmon in the Indian River
(mark rate of 13.2 percent). Detailed results related to counts of adult Chinook Salmon
spawning in the Susitna River and its tributaries in 2014 are presented below and in Appendix H.
5.5.1. Indian River Escapement Estimate
Chinook Salmon abundance in the Indian River was estimated using the AUC method (Appendix
H). From July 7 to August 19, 16 aerial spawner surveys were conducted in the Indian River
(Table 4.3-1). In all three river sections combined, 127 Chinook Salmon were counted on the
first survey (July 7) and three fish were counted on the last survey (August 19; Table H-1).
Observed counts peaked at 798 Chinook Salmon on July 22. Estimated observer efficiencies
ranged from 40 to 80 percent (Table H-1). The lowest observer efficiencies occurred on July 19
due to poor weather conditions. For most surveys, conditions ranged from good to excellent.
Chinook Salmon counts in the Indian River were very similar during concurrent surveys
conducted by the study team and ADF&G. ADF&G counted 558 Chinook Salmon on July 31
(S. Ivey, ADF&G, Sport Fish Division, personal communication) and the study team observers
counted 544 Chinook Salmon on August 1.
For the purpose of analysis, it was assumed that no Chinook Salmon were present in the Indian
River prior to June 26 or after August 19 (Figure H-1). No Chinook Salmon were observed at
the Indian River weir through June 25, and survey crews indicated that the three remaining live
Chinook Salmon observed on August 19 were moribund. Residence times above Bridge 1 for
radio-tagged large Chinook Salmon averaged 15.0 days and ranged from 0.1 to 60.6 days
(median = 15.6 days, n = 184; Figure H-2). Based on the observed aerial survey counts,
estimated observer efficiencies, and median residence time of radio -tagged fish, the estimated
escapement of large Chinook Salmon above Bridge 1 in 2014 was 1,297 fish (Table H-2).
Over the study period, 184 radio-tagged large Chinook Salmon were detected above Bridge 1, of
which 171 were tagged in the Middle River and 13 were tagged in the Lower River. Thus, the
mark rate of large Chinook Salmon at the Middle River fishwheels was estimated to be 13.2
percent (171 tags/1,297 fish; Table H-2).
In 2013, estimated observer efficiencies for Chinook Salmon in the Indian River during the study
team and ADF&G aerial spawner surveys ranged from 35.8 to 46.3 percent (Table H-1 in AEA
2014c). Based on the 2013 results, it is possible the 2014 estimates of observer efficiency were
biased high. For this reason the study team conducted a sensitivity analysis of the 2014
escapement estimate and mark rate to determine how sensitive calculations were to a small
decrease in observer efficiency. All else remaining constant, decreasing observer efficiencies by
15 percent for each survey and river reach led to a 29 percent increase in the escapement
estimate (from 1,297 to 1,674 fish) and a 23 percent decrease in the mark rate (from 13.2 to 10.2
percent).
5.5.1.1. Programmatic Summary
In the Middle River, efforts to count Chinook Salmon in tributaries from 2012 to 2014 were
focused on Indian River (with some minor effort in Portage Creek in 2012) for the purposes of
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estimating survey-area mark rates (to test the representativeness of tagging efforts), estimating
abundance above the tagging site, and making inferences about the relative abundance among
recovery locations. Visual counts (stream walks) in the Indian River and Portage Creek in 2012
proved difficult due to the removal of Chinook Salmon by bears. In 2013, 1,137 large Chinook
Salmon were inspected for tags at the Indian River weir, of which 72 (6.3 percent) were radio-
tagged. Based on the number of fish entering the study area, mark -recapture methods were used
to estimate that 6,952 (SE = 682) large Chinook Salmon passed the Gateway Station in the
Middle River from June 18 to July 28 in 2013. In 2014, since the Indian River weir was
rendered inoperable, AUC methods were used to generate an escapement estimate of 1,297 large
Chinook Salmon, of which 13.2 percent were tagged.
5.5.2. Estimated Abundance of Chinook Salmon Upstream of Devils Canyon
Abundance of Chinook Salmon upstream of Devils Canyon was estimated using two methods.
The first method expanded the counts of radio-tagged fish by the ‘mark rate’ (i.e., the proportion
of fish that were marked). In 2014, the mark rate was 13.2 percent: approximately one in every
7.6 large Chinook Salmon at the Middle River fishwheels was tagged (Table H-2). For this
method, it is important to understand that the positions of the fixed-station receivers and the
extensive mobile survey effort made it unlikely that any radio-tagged fish passed upstream of
Devils Canyon undetected. Since, in 2014, two radio-tagged large Chinook Salmon passed
Impediment 3, and one tagged fish passed the Watana Dam site (Tables 5.3-1 and 5.3-2), the
study team would expect that 15.2 large Chinook Salmon (2 divided by 13.2 percent) passed
Impediment 3, and 7.6 fish (1 divided by 13.2 percent) passed Watana Dam site.
In 2014, a second independent method was available to estimate the number of salmon that
passed the dam site. Specifically, a sonar was deployed at the Watana site, and a total of 24
salmon-sized targets passed during the study period. Given the species composition of the radio-
tagged fish that passed Impediment 3, coupled with that from spawner surveys, it is probable that
all of these targets were Chinook Salmon. Together, these two methods suggest that the
abundance of Chinook Salmon upstream of the dam site likely ranged from 7.6 to 24 fish.
5.5.2.1. Programmatic Summary
The abundance of Chinook Salmon passing Devils Canyon was not directly estimated in 2013 or
2014 (e.g., using mark-recapture methods). However, mark rates established for large Chinook
Salmon in the Indian River, combined with the number of radio-tagged fish present above Devils
Canyon, were used to make inferences about the relative abundance of large Chinook Salmon
above Devils Canyon. In 2013, an estimated 48 large Chinook Salmon migrated above Devils
Canyon (3 radio tags present above Devils Canyon expanded by 6.3 percent mark rate).
Although too few radio-tagged fish migrated above Devils Canyon to develop a statistically
precise estimate, an estimate of similar magnitude was produced when the peak aerial spawner
count was expanded by the estimated observer efficiency (29 fish counted expanded by 46.3
percent observer efficiency = 63 fish total).
In 2014, results from three independent study components indicated that the abundance of large
Chinook Salmon above Devils Canyon was likely on the order of magnitude of 50 fish or less,
with a portion of that number passing above the potential dam site. First, aerial spawner surveys
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of clear-water tributaries above Devils Canyon had a peak count of 12 Chinook Salmon (10 in
Devil Creek, 2 in Fog Creek). If the observer efficiencies on these surveys were as low as 40–50
percent, the peak count would expand to only 24–30 fish. Second, a net-upstream count of 24
salmon-sized fish was obtained at the Watana Canyon sonar site in 2014. Although this count
was considered a minimum estimate, there was no evidence to suggest that fish passage at the
site was significantly greater than that observed. And third, based on a 13.2 percent mark rate
for large Chinook Salmon at the Middle River tag site, the two radio-tagged fish that migrated
above Devils Canyon represented approximately 15 fish in total.
5.6. Objective 7: Collect tissue samples to support the Fish
Genetics Study
Genetic samples were collected from 4,016 Chinook, 395 Chum, 2,074 Coho, 798 Pink, and 336
Sockeye salmon across the three study years and sample locations. In 2012, 443 Chinook
Salmon were sampled. In 2013, genetic samples were collected from 1,999 Chinook, 201 Chum,
1,016 Coho, 399 Pink, and 138 Sockeye salmon. In 2014, genetic samples were collected from
659 Chinook, 640 Coho, and 198 Pink salmon in the Lower River. Genetic samples were also
collected from 296 Chinook Salmon in the Yentna River and 204 Coho Salmon in Montana
Creek. In the Middle River, genetic samples were collected from 619 Chinook (small and large
fish combined), 194 Chum, 214 Coho (199 at fishwheels, 15 in gillnets), 201 Pink, and 198
Sockeye salmon in 2014 (Table A-6). All genetic tissue samples were delivered to ADF&G’s
Gene Conservation Lab for analysis. Results were reported by the Genetic Baseline Study for
Selected Fish Species (Study 9.14).
The study team completed all tasks required to fulfill the requirements of study Objective 7.
Genetic samples were collected from adult anadromous salmon in conjunction with addressing
study objectives 1 and 2. All samples were delivered to ADF&G’s Gene Conser vation Lab for
analysis, and results were reported by the Genetic Baseline Study for Selected Fish Species
(Study 9.14).
5.7. Objective 8: Estimate the system-wide Chinook Salmon
escapement and the Coho Salmon escapement to the Susitna
River above the Yentna River, and the distribution of those fish
among tributaries of the Susitna River
In 2013, the abundance of Chinook Salmon measuring 50 cm (19.7 in) METF or greater
spawning in the Susitna River above the Lower River mainstem tagging site was 89,463
(SE = 9,523). Based on radio-telemetry tracking results (see Table 5.2-1 in the ISR), it is
estimated that Deshka, Talkeetna and Chulitna Rivers were the main destinations (Figure 5.7-1).
As discussed in Study 9.7 ISR Appendix I, no estimate was produced for the Yentna River in
2013.
In 2014, the system-wide escapement estimate for Chinook Salmon was 68,225 [SE = 10,615]
upstream of the confluence of the Yentna River and 22,267 [SE = 2,871] in the Yentna River).
Based on radio-telemetry tracking results (Table 5.2-1), it is estimated that Deshka, Talkeetna
and Chulitna Rivers were the main destinations (Figure 5.7-2) upstream of Yentna River.
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The 2014 escapement estimate (84,879; SE = 9,550) for Coho Salmon measuring 40 cm (15.7 in)
METF or greater above the Lower River tagging site was 35 percent lower than the 2013
estimate (130,026; SE = 24,342). Based on radio-telemetry tracking results (Table 5.2-1), it is
estimated that Deshka, Talkeetna and Chulitna Rivers were the main destinations in both years
(Figures 5.7-3 and 5.7-4).
Detailed results related to the 2014 escapement and distribution estimates as part of Objective 8
are provided in Appendix I.
6. DISCUSSION
This Discussion section focuses on Objective 5 of the RSP: “Compare historical and current data
on run timing, distribution, relative abundance, and specific locations of spawning and holding
salmon.” Recent and historic data pertinent to these aspects of salmon ecology are reviewed by
species for the Lower and Middle Susitna River.
Fish abundance as calculated by mark-recapture experiments (i.e., escapement estimates) were
determined in the early 1980’s (1981-1984), and recently as part of the Susitna-Watana project.
Marking target species was accomplished with visual tags or radio-tags via capture by
fishwheels. A portion of the tags were then recovered at weirs or by telemetry monitoring at
strategic locations in the basin. Historically, escapement estimates were derived for the Lower
Susitna (Sunshine Station), the Middle Susitna (Talkeetna Station), and select tributaries. More
recent (2000’s) Lower River estimates are available for salmon species except Pink Salmon, and
recent Middle River estimates are available for Chinook and Coho salmon. All studies partition
out abundance of the Yentna River so that general comparisons can be made between the
historical and recent estimates upstream of its confluence. Estimating Chinook and Coho salmon
abundance in 2013 and 2014 accomplishes Objective 8 of the Study Plan.
Habitat classifications described during studies conducted in the 1980’s (Barrett et al. 1985a,b;
Thompson et al. 1986) were not defined exactly as in the 2012-2014 studies, and should be taken
into consideration when making comparisons. Specifically, spawning habitat studies conducted
from 1981 to 1983 classified a “tributary mouth” as including the lower 1/3 mile of the tributary,
and survey sections did not sample the zone of confluence with tributary and the Susitna River.
However, in 1984, the methodological approach was modified, and spawning behavior at the
confluence of the tributary was documented for several streams in the Middle River (Barrett et
al. 1985a,b). For the purpose of analysis, only historic spawning locations that specifically
mentioned the confluence with the Susitna River were used for comparison with recent spawning
locations.
6.1. Chinook
6.1.1. Timing of Migration
Lower River
Fishwheel catches were compared among years to assess variability in the timing of migration
through the Lower River; however, it should be noted that some conditions varied across years
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(e.g., number of fishwheels operated, location of fishwheels, operational period, daily fishing
effort, river discharge, relative fish abundance). From 2012 to 2014, fishwheels were operated in
the Lower River (PRM 33–34) and Chinook Salmon were captured as early as May 22 and as
late as August 19. Peak catches occurred in early to mid-June in 2012, 2013, and 2014. This run
timing from recent studies is considerably earlier that than reported from studies in the 1980s.
In 1982 and 1983, Chinook Salmon were captured from June 28 to September 2 at the Lower
River fishwheels (ADF&G 1983b, 1984). At the Flathorn fishwheels (PRM 26–28), Chinook
Salmon were caught between June 30 and August 27 in 1984 and 1985 (Barrett et al. 1985a,b;
Thompson et al. 1986). And in 1983, Chinook Salmon were captured at the Sunshine fishwheels
(~PRM 84) from June 5 to August 18 (ADF&G 1984).
Middle River (downstream of Devils Canyon)
Fishwheels were operated in the Middle River near Curry from 1981 to 1985 and 2012 to 2014.
Again, it should be noted that many factors related to fishwheel sampling were not constant
across years. From 2012 to 2014, Chinook Salmon (all sizes combined) were captured at the
Middle River fishwheels as early as June 11 and as late as August 28 (Table A-8, Figure A-13).
This run timing was similar to historic records from the 1980s, when the earliest that a Chinook
Salmon was captured at the Middle River fishwheels was June 9 (1984) and the latest was
August 20 (1981; Table A-8, Figure A-13). The midpoint of Chinook Salmon catches ranged
from June 30 to July 3 for the years 2012 to 2014, and from June 24 to July 9 for the years 1981
to 1985. The dates of peak catch were similar over the recent 3-year period (July 2 in 2012 and
2013, and July 1 in 2014).
Middle River (upstream of Devils Canyon), Watana Dam, Upper River
Migration timing for radio-tagged Chinook Salmon passing Impediment 3 in the Middle River
was fairly consistent in recent study years and ranged from July 17–20 in 2012 (n = 12), July 13–
30 in 2013 (n = 3), and July 30 to August 4 in 2014 (n = 2). This timing was similar to that of
Chinook Salmon observed upstream of Impediment 3 during two years of aerial spawner surveys
(2012 and 2013). Furthermore, at the proposed Watana Dam site, shore-based sonar units
detected fish determined as Chinook Salmon, from July 10 to August 22 in 2014 (Appendix G)
and on July 20, 2013. There was no run timing data upstream of Devils Canyon from the 1980s
studies to compare to recent studies.
6.1.2. Timing of Spawning
Lower River and Tributaries
The migration timing of Chinook Salmon in the Lower River was slightly earlier and more
protracted for recent studies as compared to timing data from the 1980s. For Chinook Salmon
classified to the Yentna, Deshka, Chulitna or Talkeetna rivers, the 10th and 90th percentile dates
when fish were spawning ranged from June 24 to August 10. Each potential mainstem spawner
had a single location position that was selected as representative of its ‘cluster’ (see Section
4.2.3.2), and each of those representative locations had an associated date. The 10th and 90th
percentile dates for Chinook Salmon Lower River mainstem destinations ranged from June 22 to
September 2. In comparison, from 1981 through 1984, the spawning period for Chinook Salmon
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in the Lower River ranged from mid-July through mid-August, with peak spawning occurring
during the last week of July (summarized in Barrett et al. 1985a,b).
Middle River (within and downstream of Devils Canyon) and Tributaries
For Chinook Salmon classified to Indian River or Portage Creek, the 10th and 90th percentile
dates during which fish were in the tributary to which they were classified spanned from July 8
to August 6. The 10th and 90th percentile ‘representative’ dates for Chinook Salmon Middle
River mainstem destinations downstream of Devils Canyon ranged from July 12 to August 3. In
comparison, from 1981 through 1984, the spawning period for Chinook Salmon in the Middle
River was very similar ranging from mid-July through mid-August, with peak spawning
occurring during the last week of July (summarized in Barrett et al. 1985a,b). For Chinook
Salmon classified to Devils Canyon tributaries (Cheechako or Chinook creeks), the 10th and
90th percentile dates during which fish were in the tributary to which they were classified
spanned from July 17 to August 7. From 2012-2014, two Chinook Salmon were classified as
having mainstem destinations within Devils Canyon. The ‘representative’ dates for the two fish
were July 21 and September 2.
Middle River (upstream of Devils Canyon), Watana Dam, Upper River and Tributaries.
For Middle River tributaries upstream of Devils Canyon (Devils or Tsusena creeks), the 10th and
90th percentile dates ranged from July 22 to August 9. In the Upper River (i.e., in Kosina Creek
and its tributaries), date ranges were July 23 to August 11.
Aerials surveys conducted in the 1980s documented few spawners in the areas upstream of
Devils Canyon. In 1983, the single aerial survey over Devil Creek (August 1) documented the
presence of one fish. In 1984, four flights over Fog Creek found a peak count of two fish on July
21. Other than these few data points, the historical timing of spawning for Chinook Salmon
upstream of Devils Canyon was not previously documented.
6.1.3. Distribution to Mainstem and Tributaries
6.1.3.1. Radio-tags applied in Lower River
Lower River and Tributaries
During 2012-2014, Chinook Salmon tagged in the Lower River moved mostly into Lower River
tributaries. The main Lower River tributary destinations were the Yentna (13.2 percent), Deshka
(24.5 percent), Talkeetna (16.2 percent) and Chulitna (16.6 percent) rivers (Figure D-1). In
addition, 0.6 to 2.4 percent of the tagged Chinook Salmon in the Lower River were classified as
having mainstem destinations in the Lower River. Note that the percentages presented here were
not weighted according to size-specific tag rates, and are not directly comparable to the weighted
percentages. Similarly, from 1976-1984, most Chinook Salmon caught in the Lower River
moved into tributaries of the Lower River (summarized in Jennings 1985). In addition, estimated
percent distributions of Chinook Salmon were higher, historically, to the Yentna (20.0 percent)
and Deshka (35.0 percent) rivers and lower to the Chulitna River (5.0 percent); however, the
contribution of Chinook Salmon to the Talkeetna River was similar (Jennings 1985). Chinook
Salmon had no Lower River mainstem destinations during historic surveys.
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Middle River (within and downstream of Devils Canyon) and Tributaries
Each year during AEA’s studies, Chinook Salmon tagged in the Lower River moved into Middle
River tributaries. Fish used Indian River, and Whiskers, 4th of July and Portage creeks, together
accounting for 5.2 percent of the overall destinations of the Lower-River-tagged Chinook
Salmon (Figure D-1). In addition, between 0 and 0.5 percent were classified as having mainstem
destinations in the Middle River downstream of the canyon.
In 2013, two fish (0.3 percent) moved into a tributary destination that was in Devils Canyon
(Cheechako Creek). In 2014, one fish went to Cheechako Creek, and one fish had a mainstem
destination at the mouth of Cheechako Creek (combined, 0.3 percent of the overall destinations
of the 2013 Lower-River-tagged Chinook Salmon, or 0.2 percent as an average of the annual
usage over three years; Figure D-1).
Similar to 2012-2014, 5.0 percent of the Chinook Salmon caught in the Lower River, from 1976-
1984, had destinations within the Middle River (downstream from Devils Canyon) and
tributaries of the Middle River (Jennings 1985).
Middle River (upstream of Devils Canyon), Watana Dam, Upper River and Tributaries.
In 2012, two Lower-River-tagged Chinook Salmon passed Devils Canyon and moved into
Kosina Creek, an Upper River tributary. These fish represent 0.5 percent of the overall
destinations of the 2012 Lower-River-tagged Chinook Salmon, or 0.2 percent as an average of
the annual usage over three years (Figure D-1). In 2012-2014, no Lower-River-tagged Chinook
Salmon had mainstem destinations upstream of Devils Canyon. In comparison, from 1976-1984,
< 0.5 percent of Chinook Salmon had destinations upstream of Devils Canyon (Jennings 1985).
6.1.3.2. Radio-tags applied in Middle River
Lower River and Tributaries
Annually, there were Middle-River-tagged Chinook Salmon that moved to tributaries in the
Lower River. The main Lower River tributary destinations were the Talkeetna and Chulitna
rivers. From 2012-2014, these two tributaries represented an average of 11.3 percent of the
overall destinations of the Middle-River-tagged Chinook Salmon (Figure D-2). In 2013, two fish
(0.4 percent) were classified to mainstem destinations in the Lower River, but there were none so
classified in 2012 or 2014.
Middle River (within and downstream of Devils Canyon) and Tributaries
The majority of the Middle-River-tagged Chinook Salmon moved into tributaries in the Middle
River downstream of Devils Canyon. Indian River and Portage Creek were the main
destinations. From 2012-2014, Indian River and Portage Creek accounted for an average of 26.0
percent and 41.9 percent of the overall destinations of the Middle-River-tagged Chinook Salmon,
respectively (Figure D-2). Each year, a few Middle-River-tagged Chinook Salmon travelled to
destinations within Devils Canyon, including Cheechako (average 1.0 percent annually) and
Chinook (average 0.4 percent annually) creeks.
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Each year, a portion of the Middle-River-tagged Chinook Salmon were classified as having a
mainstem destination, and most of these were located in the Middle River downstream of Devils
Canyon. From 2012-2014, Middle-River mainstem destinations ranged from 5.3 to 9.8 percent
of the overall destinations of the Middle-River-tagged Chinook Salmon. In 2013, a single fish
(0.2 percent) had a mainstem destination within Devils Canyon (in the mainstem proper near the
mouth of Chinook Creek), whereas no Middle River-tagged Chinook Salmon had mainstem
locations within Devils Canyon in 2012 or 2014.
Middle River (upstream of Devils Canyon), Watana Dam, Upper River and Tributaries.
In 2014, two radio-tagged Chinook Salmon passed Devils Canyon, which was down from three
in 2013, and 12 in 2012, despite the fact that more large Chinook Salmon were tagged in the
Middle River during each successive year (590 in 2014, 536 in 2013, 352 in 2012). From 2012-
2014, tributary use upstream of Devils Canyon averaged 0.2 percent in Devil Creek, 0.1 percent
in Tsusena Creek, and 0.5 percent in Kosina Creek (Figure D-2). Wandering behavior was
evident in all three years of tagging although the degree that individual fish wandered varied
considerably. In 2012-2014, no Middle-River-tagged Chinook Salmon had mainstem
destinations upstream of Devils Canyon.
6.1.4. Mainstem Habitat and Tributary Use
Lower River and Tributaries
Telemetry results indicated that the majority of Chinook Salmon tagged in the Lower River
likely spawned in tributaries. Proportions of tributary spawners were relatively consistent among
years for Chinook Salmon (97–99 percent). Chinook Salmon used the Yentna, Deshka,
Talkeetna, and Chulitna rivers in all years.
From 2012 through 2014, 23 radio-tagged Chinook Salmon were identified with potential
spawning sites within mainstem macro habitats of the Lower River (Figure D-11). These radio-
tagged fish represented 14 distinct spawning locations (a cluster of points or an isolated point
represented one spawning location) of which three were associated with tributary
mouths/confluences. None of these potential spawning locations were visually confirmed.
Historic surveys only indicated spawning within tributaries and there was no indication of
spawning behavior observed at the confluence of tributaries in the Lower River (Barrett et
al.1985a,b, Thompson et al.1986).
Middle River (downstream of Devils Canyon) and Tributaries
Telemetry results indicated that most of the Chinook Salmon tagged in the Middle River were
most likely to have spawned in tributaries. Proportions in 2014 (93 percent) were similar to
those estimated in 2012 (90 percent; AEA 2013a) and 2013 (94 percent; AEA 2014c), as was the
main suite of Middle River tributary destinations (Indian River, Portage Creek), although relative
use of these tributaries varied among years. Analysis of salmon detection histories identified
several potential mainstem spawning locations in the Middle River which included the mouths of
tributaries, side channels, and main channel habitats.
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From 2012 to 2014, 100 radio-tagged Chinook Salmon were identified with potential spawning
sites within mainstem macrohabitats of the Middle River (Figure D-12; see section 5.4 for a
summary of results). Although numerous radio- tagged Chinook Salmon were tracked to
mainstem habitats, spawning activity was only confirmed at the confluence of tributary mouths.
These results are consistent with studies conducted in the 1980’s where Chinook Salmon were
only documented spawning within mainstem habitats at the confluence of five tributary mouths
(Chinook, Cheechako, Portage, and 4th of July creeks, and Indian River; Figure D-12; Barrett et
al. 1985a,b).
Results from three years of tagging, including the number of fish tagged and tracked via fixed
stations and mobile surveys, and the number of detections across river segments and habitats,
characterize the distribution of salmon throughout the Middle and Lower River. Specifically, the
data collected demonstrates that the licensing participant concern (study dispute issue) as to
whether radio-telemetry efforts as designed in the Study Plan were sufficient to determine
Chinook Salmon spawning sites in the Middle River between PRM102 (confluence of Middle
River with Lower River) and PRM124 (Curry) was not realized.
During the period 2012 through 2014, 1,681 and 1,478 Chinook Salmon were radio-tagged in the
Lower and Middle river, respectively. This resulted in the detection of 88 Lower River origin
and 500 Middle River origin Chinook Salmon tags at the Lane Creek telemetry fixed station
located at PRM 116.8. Also over these years and over the salmon migration season, a total of 80
complete aerial telemetry surveys were conducted over the river from PRM102 to PRM124.
Mobile telemetry surveys resulted in identifying a total of five potential spawning-holding
locations for Chinook Salmon in mainstem habitats (tributary confluence), and 10 tags having
their destination in tributaries (Lane, Whiskers, and Chase creeks) for that section of river. This
compares to a total of 95 potential spawning-holding locations identified for Chinook Salmon in
mainstem habitats, and 1,092 in tributaries upstream of PRM124.
Radio-tagged Chinook Salmon of Lower River origin had the same opportunity to choose
destinations in either section of the river. Further, documented roaming behavior supports that
Chinook Salmon of Middle River origin also have substantial opportunity to choose destinations
downstream of PRM124. These results indicate that the Middle River upstream of PRM124
includes a substantially higher proportion of spawning (95.0% of mainstem locations, 99.1% of
tributaries) than that downstream of PRM124 (5.0% of mainstem locations, 0.9% of tributaries),
and is consistent with historical studies (Barrett et al 1985). Therefore, the methodological
approach outlined in the Study Plan and respective variances provided sufficient sample size and
telemetry detections to evaluate spawning locations for adult Chinook Salmon in the Middle
River downstream and upstream of PRM124 and meet the objective of the study.
Middle River (within and upstream of Devils Canyon), Watana Dam, Upper River and
Tributaries.
No radio-tagged Chinook Salmon were tracked to potential mainstem, slough, or side-channel
locations in the Middle River upstream of Devils Canyon. The preponderance of evidence to
date suggests that the relatively low numbers (e.g., 50 – 100) of Chinook Salmon in the Upper
River are using tributaries for spawning. Tributaries and tributary mouths upstream of Devils
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Canyon with documented Chinook Salmon spawning included Cheechako, Fog, Devil, Tsusena,
and Kosina Creeks and the Oshetna River.
The first evidence of spawning within or upstream of Devils Canyon came in 1982 when
ADF&G found adult Chinook Salmon in Cheechako (n = 16) and Chinook (n = 5) creeks, along
with redds containing live eggs (ADF&G 1983b). The first scientific observations of Chinook
Salmon upstream of Devils Canyon came in 1983, when ADF&G found one adult fish in Devil
Creek (ADF&G 1984). In 1984, Chinook Salmon spawning was observed in Chinook (n = 15)
and Fog (n = 2) creeks. In 2003, presence of juvenile Chinook Salmon in Fog Creek, Kosina
Creek, and the Oshetna River, also implied past spawning activity (Buckwalter 2011). In 2012,
2013 and 2014, radio-tagged Chinook Salmon were detected and appeared to spawn in Kosina,
Tsusena or Devil creeks (AEA 2013a, 2014c). In total, AEA tracked 17 Chinook Salmon which
migrated above Impediment 3 (Figure F-1 through Figure F-17).
6.1.5. Abundance Estimates
Lower River (RM30)
Historically, Chinook Salmon average escapement was 88,000 (range 53,000 to 122,000) in the
Lower River at Sunshine Station (i.e., upstream of the Yentna River). This compares closely to
an average of 79,000 (approximate range 68,000 to 89,000) for 2013 and 2014 for the Susitna
River (upstream of the confluence of the Yentna River, Appendix I).
Middle River (RM120 / Curry)
Historically, Chinook Salmon average escapement was 13,000 (range 9,700 to 18,000) for the
Middle River at Talkeetna Station. This is 1.8 times higher than an average of 7,100 (range
6,600 to 7,700) for 2013 and 2014 (Appendix I).
Middle River (upstream of Devils Canyon), Watana Dam, and Upper River
Recent studies conducted by AEA from 2012 to 2014 provide the only available information on
the abundance of Chinook Salmon upstream of Devils Canyon. Radio-telemetry documented
Chinook Salmon passage through the canyon and into tributaries, and ARIS sonar made counting
of Chinook Salmon passing the Watana Dam site possible. Counts of 12, 3 and 2 radio-tags
passed Impediment 3 in 2012, 2013, and 2014 respectively. These counts were used to generate
escapement estimates for 2013 and 2014 of 23 and 24 salmon respectively. These three
independent metrics indicate that the population of Chinook Salmon upstream of Devils Canyon
appears to be on an order of magnitude of <100 adults, with a portion of that upstream of Watana
Dam.
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6.2. Chum
6.2.1. Timing of Migration
Lower River
Chum Salmon migrate through the Lower River from early June through at least early
September. In 2013 and 2014, Chum Salmon were captured at the Lower River fishwheels
(PRM 33-34) from June 11 to August 26, and fish were still being captured on the last day of
fishwheel operation in each year so it was likely the run continued beyond these dates. Chum
Salmon daily catches peaked on July 20 in 2013 and August 7 in 2014. This migration timing is
similar to historic reports with an earlier onset of the run in recent studies. Chum Salmon were
captured in the Lower River from June 30 to September 4 during fishwheel operations in 1981
and 1982 (ADF&G 1981, 1983b).
Middle River (downstream of Devils Canyon)
Chum Salmon begin their migration through the Middle River about a month later than in the
Lower River, early July, and continue through late September. From 2012 to 2014, Chum
Salmon were caught at the Middle River as early as July 5 and as late as September 28. This
migration timing was similar to the 1980s, when Chum Salmon were caught in fishwheels
between as early as July 10 (1983) and as late as September 15 (1981) (Table A-8, Figure A-14).
The midpoint of runs as indicated by catch was August 5–12 in 2012 to 2014, and from August
3–17 in the 1980s.
6.2.2. Timing of Spawning
Lower River and Tributaries
For Chum Salmon classified to the Yentna, Chulitna or Talkeetna rivers, the 10th and 90th
percentile dates when fish were in spawning tributaries spanned from August 7 to September 13.
This estimate of spawning timing is shorter by a couple of weeks in comparison with historic
data. From 1981 through 1984, the spawning period for Chum Salmon in the Lower River
ranged from mid-August through the first week of October, with peak spawning occurring during
the last week of August through the first week of September (summarized in Barrett et al.
1985a,b).
Middle River (downstream of Devils Canyon) and Tributaries
For spawning Chum Salmon classified to Indian River or Portage Creek, the 10th and 90th
percentile dates spanned from August 5 to 30. The 10th and 90th percentile dates for Chum
Salmon Middle River mainstem destinations downstream of Devils Canyon ranged from August
8 to September 9 indicating a slightly longer spawning window. However, both of these recent
estimates of spawn timing are shorter in comparison with historic estimates. From 1981 through
1984, the spawning period for Chum Salmon in the Middle River ranged from late July through
the first week of October, (summarized in Barrett et al. 1985a,b).
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6.2.3. Distribution to Mainstem and Tributaries
6.2.3.1. Radio-tags applied in Lower River
Lower River and Tributaries
In 2012, 400 Chum Salmon tagged in the Lower River moved mostly into Lower River
tributaries. The primary Lower River tributary destinations were the Yentna (33.6 percent),
Talkeetna (2.1 percent) and Chulitna (9.1 percent) rivers (Figure D-3). In addition, 9.2 percent
of the Lower-River-tagged Chum Salmon were classified as having mainstem destinations in the
Lower River. No Chum Salmon were tagged in the Lower River in 2013 or 2014.
In comparison, historical Chum Salmon tagging results (Merizon et al. 2010) showed that 96
percent had destinations within the Lower River and tributaries of the Lower River. The
historical contributions of Chum Salmon to the Yentna (41.0 percent) and Chulitna (4.0 percent)
rivers were similar to recent results. Historical Chum Salmon contributions to the Lower River
mainstem (26.0 percent) and Talkeetna River (11.0 percent) were higher, as compared to the
2012 tracking results.
Middle River and Tributaries
In 2012, a few of the Chum Salmon tagged in the Lower River moved into Middle River
tributaries. Fish used Indian River, 4th of July and Portage creeks, together accounting for 4.2
percent of the overall destinations of the Lower-River-tagged Chum Salmon (Figure D-3). In
addition, three fish (1.0 percent) were classified as having mainstem destinations in the Middle
River. Similarly in 2009, 4.0 percent of the Lower River caught Chum Salmon had a destination
in the Middle River and tributaries (downstream of Devils Canyon; Merizon et al. 2010).
Tributary use also was similar in a 1984 study, with use of the Indian River, Portage Creek, and
4th of July Creek. However, the proportion of mainstem use was higher historically with more
than half of the Chum Salmon having spawning destinations in mainstem habitats of the Middle
River (Barrett et al. 1985a,b). No Lower River Chum Salmon had destinations within or
upstream of Devils Canyon during recent or historic studies.
6.2.3.2. Radio-tags applied in Middle River
Lower River and Tributaries
There were Middle-River-tagged Chum Salmon that moved to tributaries in the Lower River
each year from 2012 to 2014. The main Lower River tributary destinations were the Talkeetna
and Chulitna rivers. These two tributaries represented an average of 12.7 and 2.6 percent of the
overall destinations of the Middle-River-tagged Chum Salmon, respectively (Figure D-4). In
three years of tracking, no Middle-River-tagged Chum Salmon were classified to mainstem
destinations in the Lower River.
Middle River and Tributaries
The majority of the Middle-River-tagged Chum Salmon moved into tributaries in the Middle
River downstream of Devils Canyon. Indian River and Portage Creek were the main
destinations. From 2012-2014, Indian River and Portage Creek accounted for an average of 27.5
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percent and 23.6 percent of the overall destinations of the Middle-River-tagged Chum Salmon,
respectively (Figure D-4). Each year, a portion (ranging from 10.4 to 23.9 percent) of the
Middle-River-tagged Chum Salmon were classified as having a mainstem destination, all of
which were located in the Middle River downstream of Devils Canyon. In three years of
tracking, no Middle-River-tagged Chum Salmon had destinations within or upstream of Devils
Canyon.
6.2.4. Mainstem Habitat and Tributary Use
Lower River
From 2012 to 2014, 31 radio-tagged Chum Salmon were identified with potential spawning sites
within mainstem habitat of the Lower River as based on 400 tags applied in the Lower River in
2012, and 4680 tags applied in the Middle River from 2012 – 2014 (Figure D-13). None of the
potential spawning locations were visually confirmed. During historic surveys mainstem
spawning activity was documented at 33 locations (Barrett et al. 1985a,b). Six of these historic
locations were closely associated with a potential spawning location indicated by recent studies
(Figure D-13).
Middle River and Tributaries
Recent telemetry results indicated that most of the Chum Salmon tagged in the Middle River
likely spawned in tributaries. Proportions varied among years: 76 percent in 2012 (AEA 2013a),
90 percent in 2013 (AEA 2014c), and 89 percent in 2014. Although the main suite of Middle-
River tributaries was relatively stable (Indian River, Portage Creek), the proportional use of each
tributary varied among years. Analysis of salmon detection histories identified several potential
mainstem spawning locations in the Middle River. As for the types of mainstem spawning
habitats used, Chum Salmon appeared to prefer the mouths of tributaries or side channels. No
radio-tagged Chum Salmon were tracked to potential mainstem, slough, or side-channel
locations in the Middle River upstream of Devils Canyon or in the Upper River.
From 2012 to 2014, 75 radio-tagged Chum Salmon were identified with potential spawning sites
in mainstem habitat of the Middle River (Figures D-14 and D-15). Through ground surveys,
aerial surveys, and opportunistic visual surveys, spawning was visually confirmed at seven
locations indicated by radio telemetry and 16 locations visited opportunistically. Of the visually
confirmed spawning locations, 12 were sloughs, six were side channels, and five were tributary
mouths/confluences. No Chum Salmon were confirmed spawning in main channel habitats.
Chum Salmon were observed present or holding at five potential spawning locations, but
spawning behavior was not exhibited. In comparison, historic surveys visually confirmed
spawning at 73 locations within mainstem habitats (main channel, side channel, slough, and
tributary mouth confluence) of the Middle River. Of all the slough habitats that were visually
confirmed as spawning locations during this study, all were also visually confirmed during
1980’s studies (Table 6.2-1). Similarly, all but 13 mainstem spawning locations documented
during the 1980’s surveys were closely associated with a potential spawning location indicated
by recent radio telemetry analysis (Figures D-14 and D-15).
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Results from three years of tagging, including the number of fish tagged and tracked via fixed
stations and mobile surveys, and the number of detections across river segments and habitats,
characterize the distribution of salmon throughout the Middle and Lower River. Specifically, the
data collected demonstrates that the license participant concern (study dispute issue) as to
whether radio-telemetry efforts as designed in the Study Plan were sufficient to determine Chum
Salmon spawning sites in the Middle River between PRM102 (confluence of Middle River with
Lower River) and PRM124 (Curry) was not realized.
During the period 2012 through 2014, 400 and 680 Chum Salmon were radio-tagged in the
Lower and Middle river, respectively. This resulted in the detection of 24 Lower River origin
and 215 Middle River origin Chum Salmon tags at the Lane Creek telemetry fixed station
located at PRM 116.8. Also, over these years and over the salmon migration season, a total of 80
complete aerial telemetry surveys were conducted over the river from PRM102 to PRM124.
Mobile telemetry surveys resulted in identifying a total of three potential spawning-holding
locations for Chum Salmon in mainstem habitats (tributary confluence), and 11 tags having their
destination in tributaries (Lane Creek, Whiskers Creek) for that section of river. This compares
to a total of 72 potential spawning-holding locations identified for Chum Salmon in mainstem
habitats, and 378 in tributaries upstream of PRM124.
Radio-tagged Chum Salmon of Lower River origin had the same opportunity to choose
destinations in either section of the river. Further, documented roaming behavior supports that
Chum Salmon of Middle River origin also have substantial opportunity to choose destinations
downstream of PRM124. These results indicate that the Middle River upstream of PRM124
includes a substantially higher proportion of spawning (96.0% of mainstem locations, 97.2% of
tributaries) than that downstream of PRM124 (4.0% of mainstem locations, 2.8% of tributaries),
and is consistent with historical studies (Barrett et al 1985). Therefore, implementation of the
Study Plan for radio telemetry including all variances provided sufficient sample size and
telemetry detections to evaluate spawning locations for adult Chum Salmon in the Middle River
downstream upstream of PRM124 and meet the objective of the study.
6.2.5. Abundance Estimates
Lower River (RM30)
Historically, Chum Salmon average escapement was 431,000 (range 263,000 to 765,000) in the
Lower River at Sunshine Station (i.e., upstream of the Yentna River). This is lower but modestly
similar to an average of 616,000 (range 151,000 to 1,500,000) for 2010 - 2012 for the Susitna
River (upstream of the confluence of the Yentna River; Cleary et al. 2013, Cleary et al. in prep
A, Cleary et al. in prep B).
Middle River (RM120 / Curry) and Tributaries
Historically, Chum Salmon average escapement was 28,000 (range 13,000 to 49,000) for the
Middle River at Talkeetna Station. This is very similar to an average of 26,000 for 2012 - 2014
using the proportion of radio-tags with a destination in the Middle River (4.2 percent of the
Lower River escapement).
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License participants raised the concern as to whether use of existing and recent escapement
information (2010 - 2012) in combination with new distribution data in the Middle River (2012 –
2014) as designed in the Study Plan were sufficient to evaluate Chum Salmon distribution and
abundance. AEA completed three years of radio-tagging on Chum Salmon in the Middle River,
and one year in the Lower River. In combination, these data produce the recent average
abundance estimate presented above and meet the objective of the study.
6.3. Coho
6.3.1. Timing of Migration
Lower River
Based on fishwheel catches, the migration timing of Coho Salmon through the Lower River
ranged from the end of June to early September. In 2013 and 2014 Coho Salmon were captured
from June 28 to August 31. In comparison, Coho Salmon collections were later in 1981 and
1982, ranging July 4 to September 4 (ADF&G 1981, 1983b).
Middle River (downstream of Devils Canyon)
The timing of migration for Coho Salmon through the Middle River extends from late July to at
least the end of September. In 2014, the first Coho Salmon was captured at the Middle River
fishwheels on July 22, which was similar to 2013 (July 23) but 6 days earlier than in 2012 (July
28; Table A-8, Figure A-15). In the 1980s, the beginning of Coho Salmon collections was
between July 18 (1984) and August 4 (1981). The midpoint of catches in 2014 (August 20)
occurred 5 days later than in 2012 and 2013 (August 15). In the 1980s, the midpoint of catches
ranged from August 12–23. The last Coho Salmon was captured on September 30 in 2014.
Also, sonar data collected at Curry indicated that salmon-sized fish (presumably Chum and Coho
Salmon) continued to migrate past Curry through the end of September in 2014 (Figures A-19
and A-20). Prior to 2014, the latest that a Coho Salmon had been captured at the Middle River
fishwheels was September 21 (2013), although the fishwheels were shut down for the season
between September 12 and September 21 in the 1980s.
6.3.2. Timing of Spawning
Lower River and Tributaries
For Coho Salmon classified to the Yentna, Deshka, Chulitna or Talkeetna rivers, the 10th and
90th percentile dates when fish were in assigned spawning tributaries spanned from August 7 to
September 23. Spawn timing in the mainstem appeared similar with the 10th and 90th percentile
dates for Coho Salmon Lower River mainstem destinations ranging from August 9 to September
30. This spawning timing appears to be protracted and shifted earlier in comparison with historic
data. From 1981-1984, the spawning period for Coho Salmon in the Lower River ranged from
late September through mid-October, with peak spawning occurring during the last week of
September (summarized in Barrett et al. 1985a,b).
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Middle River (downstream of Devils Canyon) and Tributaries
For Coho Salmon classified to Indian River or Portage Creek, the 10th and 90th percentile dates
when fish were in assigned spawning tributaries spanned from August 20 to October 9. The 10th
and 90th percentile dates for Coho Salmon Middle River mainstem destinations downstream of
Devils Canyon ranged from August 20 to September 26. This spawn timing appears to be
shifted earlier than historically. During the 1980s, the spawning period for Coho Salmon in the
Susitna River ranged from late September through mid-October, with peak spawning occurring
during the last week of September (summarized in Barrett et al. 1985a,b).
6.3.3. Distribution to Mainstem and Tributaries
6.3.3.1. Radio-tags applied in Lower River
Lower River and Tributaries
During 2012-2014, Coho Salmon tagged in the Lower River moved mostly into Lower River
tributaries. The primary Lower River tributary destinations were the Yentna (22.8 percent),
Deshka (12.1 percent), Talkeetna (11.6 percent) and Chulitna (24.8 percent) rivers (Figure D-5).
In addition, 2.8 to 6 percent of the Lower-River-tagged Coho Salmon were classified as having
mainstem destinations in the Lower River. Similarly, Merizon et al. (2010) estimated that most
(98 percent) Coho Salmon caught in the Lower River had destination in the Lower River and
tributaries. Using data collected in the 1980’s and 2009, the distribution of Coho Salmon to the
Yentna River ranged from 23.0 percent (1980’s) to 47.0 percent (2009). The Talkeetna and
Chulitna rivers had a combined contribution of 29.0 (1980’s) to 34.0 (2009) percent. The
remaining Lower River, including the Deshka River had contributions of 27.0 (2009) to 46.0
percent (1980’s; Barrett et al. 1985a, b; Merizon et al. 2010).
Middle River and Tributaries
Each year during recent studies, Coho Salmon tagged in the Lower River moved into Middle
River tributaries. Fish used Indian River, and Whiskers, Chase, Lane and Portage creeks,
together accounting for 2.6 percent of the overall destinations of the Lower-River-tagged Coho
Salmon (Figure D-5). In addition, between 0 and 0.6 percent were classified as having mainstem
destinations in the Middle River. In comparison, of the estimated Coho Salmon that entered the
Middle River from 1981-1984, most had destinations in Gash, Whiskers, and Chase creeks and
Indian River (Barrett et al. 1985a, b). No Coho Salmon from recent or historic studies had
destination upstream of Devils Canyon.
6.3.3.2. Radio-tags applied in Middle River
Lower River and Tributaries
There were Middle-River-tagged Coho Salmon that moved to tributaries in the Lower River
during each year of recent telemetry studies. The main Lower River tributary destinations were
the Talkeetna and Chulitna rivers. From 2012-2014, these two tributaries represented an average
of 5.6 and 13.4 percent of the overall destinations of the Middle-River-tagged Coho Salmon,
respectively (Figure D-6). In three years of tracking, there were four Middle-River-tagged Coho
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Salmon (annual percentages ranged from 0 to 1.7 percent) that were classified to mainstem
destinations in the Lower River.
Middle River and Tributaries
The majority of the Middle-River-tagged Coho Salmon moved into tributaries in the Middle
River downstream of Devils Canyon. Indian River and Portage Creek were the main
destinations. From 2012-2014, Indian River and Portage Creek accounted for an average of 37.6
percent and 9.0 percent of the overall destinations of the Middle-River-tagged Coho Salmon,
respectively (Figure D-6). Each year, a portion (ranging from 5.4 to 15.9 percent) of the Middle-
River-tagged Coho Salmon were classified as having a mainstem destination in the Middle River
downstream of Devils Canyon. In three years of tracking, no Middle-River-tagged Coho Salmon
had destinations within or upstream of Devils Canyon.
6.3.4. Mainstem Habitat and Tributary Use
Lower River and Tributaries
Telemetry results indicated that the majority of Coho Salmon tagged in the Lower River likely
spawned in tributaries. Proportions of tributary spawners were relatively consistent among years
for Coho Salmon (93–96 percent). Coho Salmon used the Yentna, Deshka, Talkeetna, and
Chulitna rivers in all years.
From 2012 to 2014, 40 radio-tagged Coho Salmon were identified with potential spawning sites
in mainstem habitats of the Lower River (Figure D-16). Seven suspected spawning locations
were at tributary mouths/confluences and the remaining were either main channel, side channel,
or slough locations. None of these potential spawning locations were visually confirmed for
spawning. During surveys conducted in the 1980’s, six mainstem spawning locations were
visually confirmed for Coho Salmon. Five of these historic spawning locations were closely
associated with locations indicated from 2012- 2014 analyses.
Middle River and Tributaries
Telemetry results indicated that most of the Coho Salmon tagged in the Middle River likely
spawned in tributaries. Proportions in 2014 (94 percent) were similar to those estimated in 2012
(84 percent; AEA 2013a) and 2013 (89 percent; AEA 2014c). The specific tributary destinations
were also similar, although relative use of these tributaries varied among years. Analysis of
salmon detection histories identified several potential mainstem spawning locations in the
Middle River. As for the types of mainstem spawning habitats used, Coho Salmon appeared to
prefer the mouths of tributaries or side channels. No radio-tagged Coho Salmon were tracked to
potential mainstem, slough, or side-channel locations in the Middle River upstream from Devils
Canyon or in the Upper River.
From 2012 to 2014, 35 radio-tagged Coho Salmon were identified with potential spawning sites
in mainstem habitat of the Middle River (Figure D-17). Through ground surveys, aerial surveys,
and opportunistic visual surveys, spawning was confirmed at three locations visited
opportunistically. Of the visually-confirmed spawning locations one was a slough, and two were
at tributary mouths/confluences (Skull and Whiskers creeks). Coho Salmon were present or
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holding at two locations (Indian River and Portage Creek) indicated by radio telemetry analysis.
During spawning surveys conducted in the 1980’s, 12 mainstem spawning locations were
visually confirmed for Coho Salmon and seven were closely associated with a location indicated
by radio telemetry analyses.
Results from three years of tagging, including the number of fish tagged and tracked via fixed
stations and mobile surveys, and the number of detections across river segments and habitats,
characterize the distribution of salmon throughout the Middle and Lower River. Specifically, the
data collected demonstrates that the licensing participant concern (study dispute issue) as to
whether radio-telemetry efforts as designed in the Study Plan were sufficient to determine Coho
Salmon spawning sites in the Middle River between PRM102 (confluence of Middle River with
Lower River) and PRM124 (Curry) was not realized.
During the period 2012 through 2014, 1,653 and 638 Coho Salmon were radio-tagged in the
Lower and Middle river, respectively. This resulted in the detection of 58 Lower River origin
and 315 Middle River origin Coho Salmon tags at the Lane Creek telemetry fixed station located
at PRM 116.8. Also over these years and over the salmon migration season, a total of 80
complete aerial telemetry surveys were conducted over the river from PRM102 to PRM124.
Mobile telemetry surveys resulted in identifying a total of four potential spawning-holding
locations for Coho Salmon in mainstem habitats (tributary confluence), and 61 tags having their
destination in tributaries (Lane, Whiskers, Chase, Stash, and Gash creeks) for that section of
river. This compares to a total of 31 potential spawning-holding locations identified for Coho
Salmon in mainstem habitats, and 320 in tributaries upstream of PRM124.
Radio-tagged Coho Salmon of Lower River origin had the same opportunity to choose
destinations in either section of the river. Further, documented roaming behavior supports that
Coho Salmon of Middle River origin also have substantial opportunity to choose destinations
downstream of PRM124. These results indicate that the Middle River upstream of PRM124
includes a substantially higher proportion of spawning (88.6% of mainstem locations, 84.0 % of
tributaries) than that downstream of PRM124 (11.4% of mainstem locations, 16.0% of
tributaries), and is consistent with historical studies (Barrett et al 1985). Therefore,
implementation of the Study Plan for radio telemetry including all variances provided sufficient
sample size and telemetry detections to evaluate spawning locations for adult Coho Salmon in
the Middle River downstream and upstream of PRM124 and meet the objective of the study.
6.3.5. Abundance Estimates
Lower River (RM30)
Historically, Coho Salmon average escapement was 44,000 (range 15,000 to 95,000) in the
Lower River at Sunshine Station (i.e., upstream of the Yentna River). This is almost half of an
average of 102,000 (range 73,000 to 132,000) for the period 2010 - 2014 for the Susitna River
(upstream of the confluence of the Yentna River; Cleary et al. 2013, Cleary et al. in prep A,
Cleary et al. in prep B, Appendix I).
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Middle River (RM120 / Curry) and Tributaries
Historically, Coho Salmon average escapement was 1,600 (range 800 to 2,400) for the Middle
River at Talkeetna Station. This is approximately on quarter of recent estimate of 7,200 (range
6,200 to 8,300) based on 2013 and 2014 data (Cleary et al. 2013, Cleary et al. in prep A, Cleary
et al. in prep B, Appendix I).
6.4. Pink
6.4.1. Timing of Migration
Lower River
Pink Salmon migrate through the Lower River from late June to the end of August. In 2013 and
2014, Pink Salmon were captured at the Lower River fishwheels from June 23 to August 25.
This was very similar to historic timing from the early 1980s. In 1981 and 1982, Pink Salmon
catches occurred from June 28 to August 30 (ADF&G 1981, 1983b) and in 1985Pink Salmon
were caught at the Flathorn fishwheels from June 22 to September 1 (Thompson et al. 1986).
Middle River (downstream of Devils Canyon)
From 2012 to 2014, Pink Salmon were captured at the Middle River fishwheels as early as July 8
and as late as September 4 (Table A-8, Figure A-16). In the 1980s, Pink Salmon were caught
with a similar migration timing, as early as July 7 in 1984 to as late as August 29 in 1981 and
1984. The midpoint of catches from 2012 to 2014 ranged from July 31 to August 8, which was
similar to those observed in the 1980s (August 1–8).
6.4.2. Timing of Spawning
Lower River and Tributaries
For Pink Salmon classified to the Yentna, Deshka, Chulitna or Talkeetna rivers, the 10th and
90th percentile dates when fish were in spawning tributaries spanned from August 6 to 29. The
10th and 90th percentile dates for Pink Salmon Lower River mainstem destinations ranged from
July 31 to August 30. In comparison, from 1981 through1984, the spawning period for Pink
Salmon in the Lower River was similar. Historic Pink Salmon spawning ranged from late July
through early September, with peak spawning occurring during the first two weeks of August
(summarized in Barrett et al. 1985a, b).
Middle River (downstream of Devils Canyon) and Tributaries
For Pink Salmon classified to Indian River or to 4th of July or Portage creeks for spawning, the
10th and 90th percentile dates when fish were in the spawning tributaries spanned from July 31
to August 20. The 10th and 90th percentile dates for Pink Salmon Middle River mainstem
destinations downstream of Devils Canyon ranged from August 5 to 27. In comparison the
historic spawn timing was similar from 1981 through 1984, the spawning period for Pink Salmon
in the Middle River ranged from late July through early September, with peak spawning
occurring during the second and third week of August (summarized in Barrett et al. 1985a,b).
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6.4.3. Distribution to Mainstem and Tributaries
6.4.3.1. Radio-tags applied in Lower River
Lower River and Tributaries
During 2012-2014, Pink Salmon tagged in the Lower River moved mostly into Lower River
tributaries. The main Lower River tributary destinations were the Yentna (21.6 percent), Deshka
(12 percent), Talkeetna (5 percent) and Chulitna (21.3 percent) rivers, and Willow (7 percent)
and Montana (5.5 percent) creeks (Figure D-7). In addition, 0.6 to 14.7 percent of the Lower-
River-tagged Pink Salmon were classified as having a mainstem destination in the Lower River.
Similarly, Barrett et al. (1985a, b) indicated that, historically, most of the Pink Salmon caught in
the Lower River also had destinations in the Lower River and Tributaries. In 1984, this included
about 10.0 percent to the Yentna, 60.0 percent to tributaries between the Yentna and Sunshine
Station, and the remaining 30.0 percent had destination upstream of Sunshine Station.
Middle River and Tributaries
Each year, Pink Salmon tagged in the Lower River moved into Middle River tributaries. Fish
used Indian River, and Lane, 4th of July, Gold and Portage creeks, together accounting for 3
percent of the overall destinations of the Lower-River-tagged Pink Salmon (Figure D-7). In
2013, one fish (0.9 percent) was classified as having mainstem destinations in the Middle River
(at the mouth of 4th of July Creek). Similarly, from 1981-1984, most Pink Salmon with
destinations in the Middle River ended up in tributaries. The three most important tributary
destinations were tributaries used in recent years, Indian River, 4th of July Creek and Lane Creek
(Barrett et al. 1985a,b). No Lower-River-tagged Pink Salmon had destinations within or
upstream of Devils Canyon either historically or in recent studies.
6.4.3.2. Radio-tags applied in Middle River
Lower River and Tributaries
Annually, there were Middle-River-tagged Pink Salmon that moved to tributaries in the Lower
River during each year of recent studies. The main Lower River tributary destinations were the
Talkeetna and Chulitna rivers. From 2012-2014, these two tributaries represented an average of
11.7 and 2.2 percent of the overall destinations of the Middle-River-tagged Pink Salmon,
respectively (Figure D-8). In three years of tracking, no Middle-River-tagged Pink Salmon were
classified to mainstem destinations in the Lower River.
Middle River and Tributaries
The majority of the Middle-River-tagged Pink Salmon moved into tributaries in the Middle
River downstream of Devils Canyon. Indian River and 4th of July and Portage creeks were the
main destinations, accounted for an average of 34.7, 9.6 and 10.7 percent of the overall
destinations of the Middle-River-tagged Pink Salmon, respectively (Figure D-8). Each year, a
portion (ranging from 5.5 to 9.0 percent) of the Middle-River-tagged Pink Salmon were
classified as having a mainstem destination, all of which were located in the Middle River
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downstream of Devils Canyon. In three years of tracking, no Middle-River-tagged Pink Salmon
had destinations within or upstream of Devils Canyon.
6.4.4. Mainstem Habitat and Tributary Use
Lower River and Tributaries
Telemetry results indicated that the majority of Pink Salmon tagged in the Lower River likely
spawned in tributaries. Proportions of tributary spawners were more variable for Pink Salmon
(84–97 percent) compared to Chinook or Coho salmon. Pink Salmon used the Yentna and
Deshka rivers in all three years, and used Willow and Montana creeks and Talkeetna and
Chulitna rivers to extents that varied among years (AEA 2013a, 2014c).
In contrast to 2013, when 16 percent of the Lower River Pink Salmon were classified to
mainstem destinations (AEA 2014c), 1–3 percent were so classified in 2012 and 2014 (AEA
2013a). The difference can most likely be explained by lower tracking effort in tributaries in
2013, thus biasing Pink Salmon classifications away from tributary designations, and creating the
appearance of a higher proportion of mainstem spawning. With higher effort of tributary
tracking in 2012 and 2014, the mainstem spawning results were likely more realistic than in
2013.
From 2012 through 2014, 12 radio-tagged Pink Salmon were identified with potential spawning
sites within mainstem habitats of the Lower River (Figure D-18). Of these, eight were associated
with tributary mouths/confluences. Spawning was not visually confirmed for any Lower River
potential spawning locations for Pink Salmon. Similarly, during spawning surveys conducted in
the 1980’s, Pink Salmon spawning was not observed within mainstem habitats of the Lower
River.
Middle River and Tributaries
Telemetry results indicated that most of the Pink Salmon tagged in the Middle River likely
spawned in tributaries. Proportions in 2014 (93 percent) were similar to those estimated in 2012
(94 percent; AEA 2013a) and 2013 (91 percent; AEA 2014c), as were the primary Middle River
tributary destinations (4th of July Creek, Indian River, Portage Creek), although the relative use
of these tributaries varied among years. Analysis of salmon detection histories identified several
potential mainstem spawning locations in the Middle River. As for the types of mainstem
spawning habitats used, Pink Salmon appeared to prefer the mouths of tributaries or side
channels. No radio-tagged Pink Salmon were tracked to potential mainstem, slough, or side-
channel locations in the Middle River upstream of Devils Canyon nor in the Upper River.
From 2012 through 2014, 21 radio-tagged Pink Salmon were identified with potential spawning
sites within mainstem habitats of the Middle River (Figure D-19). Spawning was visually
confirmed at three locations (Indian River Mouth, 4th of July Creek Mouth, and Lane Creek
Mouth) as indicated by radio telemetry and at three additional locations (Portage, Gold, and 5th
of July creek mouths) visually confirmed during opportunistic surveys. Spawning surveys
conducted in the 1980’s visually confirmed spawning by Pink Salmon at twenty locations; four
were tributary mouth confluences (Fourth of July, Skull, and Portage creeks and Indian River)
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and 16 were slough habitats (Table 6.2-1). Nine of the historic spawning locations were closely
associated with potential spawning locations indicated by recent studies.
Results from three years of tagging, including the number of fish tagged and tracked via fixed
stations and mobile surveys, and the number of detections across river segments and habitats,
characterize the distribution of salmon throughout the Middle and Lower River. Specifically, the
data collected demonstrates that the licensing participant concern (study dispute issue) as t o
whether radio-telemetry efforts as designed in the Study Plan were sufficient to determine Pink
Salmon spawning sites in the Middle River between PRM102 (confluence of Middle River with
Lower River) and PRM124 (Curry) was not realized.
During the period 2012 through 2014, 796 and 631 Pink Salmon were radio-tagged in the Lower
and Middle river, respectively. This resulted in the detection of 28 Lower River origin and 328
Middle River origin Pink Salmon tags at the Lane Creek telemetry fixed station located at PRM
116.8. Also over these years and over the salmon migration season, a total of 80 complete aerial
telemetry surveys were conducted over the river from PRM102 to PRM124. Mobile telemetry
surveys resulted in identifying a total of three potential spawning-holding locations for Pink
Salmon in mainstem habitats (tributary confluence), and 39 tags having their destination in
tributaries (Lane and Whiskers creeks) for that section of river. This compares to a total of 18
potential spawning-holding locations identified for Pink Salmon in mainstem habitats, and 373 in
tributaries upstream of PRM124.
Radio-tagged Pink Salmon of Lower River origin had the same opportunity to choose
destinations in either section of the river. Further, documented roaming behavior supports that
Pink Salmon of Middle River origin also have substantial opportunity to choose destinations
downstream of PRM124. These results indicate that the Middle River upstream of PRM124
includes a substantially higher proportion of spawning (85.7% of mainstem locations, 90.5% of
tributaries) than that downstream of PRM124 (14.3% of mainstem locations, 9.5% of tributaries),
and is consistent with historical studies (Barrett et al 1985). Therefore, implementation of the
Study Plan for radio telemetry including all variances provided sufficient sample size and
telemetry detections to evaluate spawning locations for adult Pink Salmon in the Middle River
downstream and upstream of PRM124 and meet the objective of the study.
6.4.5. Abundance Estimates
Lower River (RM30) and Middle River (RM120 / Curry)
Historically, Pink Salmon average escapement was 388,000 (range 40,000 to 1,017,000) in the
Lower River at Sunshine Station (i.e., upstream of the Yentna River), and average escapement
was 46,000 (range 1,000 to 117,000) for the Middle River at Talkeetna Station. No escapement
estimates were made for recent studies.
Licensing participants posited that an escapement estimate was needed for Pink Salmon (FERC
2013b). In the 1980’s Pink Salmon abundance estimates varied 120- to 50-fold from year to year
and seven-fold between even year returns (ADF&G 1983b, 1985a,b). Recent data from
ADF&G’s Deshka River weir showed that even year returns varied 40-fold from 2004-2012
(AEA 2013b). Due to this wide inter-annual variation documented for Pink Salmon abundance,
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two years of abundance estimates would provide little, or no, additional value for determining
impacts of project developments.
6.5. Sockeye
6.5.1. Timing of Migration
Lower River
Sockeye Salmon migrate through the Lower River from approximately late May to the start of
September. In recent years (2013 and 2014), Sockeye Salmon were captured at the Lower River
fishwheels from June 4 to August 26. This migration timing is similar to historic records. Based
on Lower River fishwheel catches from 1982 to 1984, the migration timing for the first run of
Sockeye Salmon ranged from May 26 - June 28 with peak migration occurring during mid-June
(Barrett et al. 1985a,b; Thompson et al. 1986). Similarly, fishwheel catches from 1981-1984
describe the migration timing for the second run of Sockeye Salmon as occurring from June 27
(1982) to September 12 (1982) with peak migrations occurring from mid-to late July (Barrett et
al. 1985,a,b; Thompson et al. 1986)
Middle River (downstream of Devils Canyon)
Migration timing for Sockeye Salmon in the Middle River has been relatively consistent across
the years. From 2012 to 2014, Sockeye Salmon were captured between June 15 and September
10 (Table A-8, Figure A-17). This run timing and duration was similar to the 1980s, when the
earliest that a Sockeye Salmon was captured was June 26 (1984) and the latest was September 18
(1982). Consistent with 2012 and 2013, catches of Sockeye Salmon in 2014 were relatively low
and sporadic through July and August. The midpoint of catch in 2014 (August 1) was consistent
with previous records, although earlier than 1981 to 1983, 1985, and 2013 (range: August 5–7),
and similar to 1984 and 2012 (range: July 30 to August 1).
6.5.2. Timing of Spawning
Lower River and Tributaries
For Sockeye Salmon classified as spawning in the Yentna, Chulitna or Talkeetna rivers, the 10th
and 90th percentile dates when fish were spawning spanned from August 7 to September 13.
From 2012-2014, three Sockeye Salmon were classified as having mainstem destinations in the
Lower River. The spawn timing for the three fish was earlier than that estimated for tributary
spawning (July 17 and 25) but was similar to historic timing. In 1981 through 1984, the
spawning period for Sockeye Salmon in the Lower River ranged from mid-to late July for the
first run and from late August through early October for the second run. Peak spawning for the
second run occurred during the last week of August through mid-September (summarized in
Barrett et al. 1985a, b).
Middle River (downstream of Devils Canyon) and Tributaries
For Sockeye Salmon classified as spawning in Indian River or Portage Creek, the 10th and 90th
percentile dates when fish were in the spanned from July 26 to September 7. The 10th and 90th
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percentile dates for Sockeye Salmon Middle River mainstem destinations downstream of Devils
Canyon were later than in tributaries and occurred over a shorter duration. Mainstem dates
ranged from August 16 to September 20 during recent studies. Historic data indicates that
Middle River Sockeye Salmon spawning was more similar to timing of recent mainstem
spawners and was protracted as spawning continued into October. From 1981 through 1984, the
spawning period for Sockeye Salmon in the Susitna River ranged from late August through early
October, with the peak spawning occurring during the last week of August through mid-
September (summarized in Barrett et al. 1985a, b).
6.5.3. Distribution to Mainstem and Tributaries
6.5.3.1. Radio-tags applied in Lower River
Lower River and Tributaries.
In 2012, 100 Sockeye Salmon tagged in the Lower River moved mostly into Lower River
tributaries. The overwhelming majority moved into the Yenta River (96 percent), however fish
also used Deshka (1 percent) and Chulitna (2 percent) rivers (Figure D-9). None of the Lower-
River-tagged Sockeye Salmon were classified as having mainstem destinations in the Lower
River. Similarly, most Sockeye Salmon destinations from historic surveys in the Lower River
were within tributaries (Fair 2009; Yanusz et al. 2011a, b). The Yentna River received up to
80.0 percent of the Sockeye Salmon distribution while the Talkeetna and Chulitna river basins
followed in importance with 14.5 and 5.0 percent distribution, respectively. In the 1980s,
however, the Yentna River was estimated as having 48.0 percent of the Sockeye Salmon
distribution while the Talkeetna and Chulitna Rivers made up the 46.0 percent (ADFG 1981,
1982; Barrett et al. 1985a, b; Thompson et al. 1986).
Middle River and Tributaries
Sockeye Salmon tagged in the Lower River in 2012 did not use any Middle River tributaries.
However, a single fish (1 percent) was classified as having a mainstem destination in the Middle
River. Historically, about 1.0 (1980’s) to 2.0 (2007-2008) percent of Sockeye Salmon had
destinations within the Middle River and tributaries (ADFG 1981, 1982; Barrett et al. 1985a,b;
Thompson et al. 1986; Fair 2009; Yanusz et al. 2011a,b). Of the Sockeye Salmon that had
destinations in the Middle River, 98.0 percent had mainstem destinations (sloughs) while < 1.0
percent had a destination in Indian River. No Sockeye Salmon, from either the recent or historic
data set, had destinations within or upstream of Devils Canyon.
6.5.3.2. Radio-tags applied in Middle River
Lower River and Tributaries
There were Middle-River-tagged Sockeye Salmon that moved to tributaries in the Lower River
during each year of recent studies. The main Lower River tributary destinations were the
Talkeetna and Chulitna rivers. From 2012-2014, these two tributaries represented an average of
10.2 and 9.2 percent of the overall destinations of the Middle-River-tagged Sockeye Salmon,
respectively (Figure D-10). In 2013 three fish (3.3 percent) were classified to mainstem
destinations in the Lower River, but there were none so classified in 2012 or 2014.
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Middle River and Tributaries
Middle-River-tagged Sockeye Salmon were the most likely group to be classified with a
mainstem destination in the Middle River, with annual proportions ranging from 46.5 to 78.7
percent in 2012-2014. Many of the remaining fish moved into tributaries in the Middle River
downstream from Devils Canyon. Indian River, and 4th of July and Portage creeks were the
main destinations, accounting for an average of 3.9, 1.3 and 4.9 percent of the overall
destinations of the Middle-River-tagged Sockeye Salmon, respectively (Figure D-10). In three
years of tracking, no Middle-River-tagged Sockeye Salmon had destinations within or upstream
of Devils Canyon.
6.5.4. Mainstem Habitat and Tributary Use
Lower River and Tributaries
From 2012 through 2014, no radio-tagged Sockeye Salmon were identified with potential
spawning sites in mainstem habitats of the Lower River (based on 100 tags applied in the Lower
River in 2012, and 409 tags applied in the Middle River from 2012 – 2014). Similarly, spawning
surveys conducted during the 1980’s found no evidence of Sockeye Salmon spawning in Lower
River mainstem habitats.
Middle River and Tributaries
For Sockeye Salmon, the percent tracked into tributaries varied among years (21–54 percent),
but never approached the levels seen for other salmon species in the Middle River, or for
Sockeye Salmon in the Lower River. Primary Middle River tributaries used included Indian
River and Portage Creek. Analysis of salmon detection histories identified several potential
mainstem spawning locations in the Middle River. As for the types of mainstem spawning
habitats used, Sockeye Salmon showed a stronger preference for sloughs. Of particular interest
to Sockeye Salmon in all three years were Slough 8A, Slough 9, and Slough 11 (e.g., in 2014, 46
spawning Sockeye Salmon were classified to these three sloughs, i.e., 32 percent of the number
classified to a destination, and 70 percent of the total number that were classified to a mainstem
destination). No radio-tagged Sockeye Salmon were tracked to potential mainstem, slough, or
side-channel locations in the Middle River upstream of Devils Canyon or in the Upper River.
From 2012 through 2014, 104 radio-tagged Sockeye Salmon were identified with potential
spawning sites within mainstem habitats of the Middle River. Ten locations indicated by radio
telemetry were visually confirmed for spawning by Sockeye Salmon (Figure D-20). This
included nine sloughs (Table 6.2-1) and one side channel (Side Channel 21). Sockeye Salmon
were present or holding at two locations (Portage Creek Mouth and 4th of July Side Channel), but
spawning behavior was not observed. Additionally, opportunistic surveys visually confirmed
spawning at two locations. Spawning surveys conducted in the 1980’s visually confirmed 27
mainstem spawning locations for Sockeye Salmon (Figure D-20; Table 6.2-1). Of these, 23 were
within slough habitats, three were within main channel or side channel habitats, and one was at
the confluence of a tributary mouth (Portage Creek). Thirteen of the 27 historic spawning
locations for Sockeye Salmon were closely associated with a potential spawning location
indicated by radio telemetry.
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Results from three years of tagging, including the number of fish tagged and tracked via fixed
stations and mobile surveys, and the number of detections across river segments and habitats,
characterize the distribution of salmon throughout the Middle and Lower River. Specifically, the
data collected demonstrates that the licensing participant concern (study dispute issue) as to
whether radio-telemetry efforts as designed in the Study Plan were sufficient to determine
Sockeye Salmon spawning sites in the Middle River between PRM102 (confluence of Middle
River with Lower River) and PRM124 (Curry) was not realized.
During the period 2012 through 2014, 100 and 409 Sockeye Salmon were radio-tagged in the
Lower and Middle river, respectively. This resulted in the detection of three Lower River origin
and 237 Middle River origin Sockeye Salmon tags at the Lane Creek telemetry fixed station
located at PRM 116.8. Also over these years and over the salmon migration season, a total of 80
complete aerial telemetry surveys were conducted over the river from PRM102 to PRM124.
Mobile telemetry surveys resulted in identifying one potential spawning/holding location for
Sockeye Salmon and zero tags having their destination in tributaries for that section of river. This
compares to a total of 104 potential spawning-holding locations identified for Sockeye Salmon in
mainstem habitats, and 41 in tributaries upstream of PRM124.
Radio-tagged Sockeye Salmon of Lower River origin had the same opportunity to choose
destinations in either section of the river. Further, documented roaming behavior supports that
Sockeye Salmon of Middle River origin also have substantial opportunity to choose destinations
downstream of PRM124. These results indicate that the Middle River upstream of PRM124
includes a substantially higher proportion of spawning (100% of mainstem locations, 97.6% of
tributaries) than that downstream of PRM124 (0% of mainstem locations, 2.4% of tributaries),
and is consistent with historical studies (Barrett et al 1985). Earlier Sockeye Salmon studies,
applying ~550 radio-tags to Sockeye Salmon in the Lower River (Yanusz et al. 2011a,b), did not
track any of those fish to destinations in the Middle River downstream of PRM124. Therefore,
implementation of the Study Plan for radio telemetry including all variances and other recent
studies provided sufficient sample size and telemetry detections to evaluate spawning locations
for adult Sockeye Salmon in the Middle River downstream and upstream of PRM124 and meet
the objective of the study.
6.5.5. Abundance Estimates
Lower River (RM30)
Historically, Sockeye Salmon average escapement was 122,000 (range 71,000 to 152,000) in the
Lower River at Sunshine Station (i.e., upstream of the Yentna River). This is higher than but
modestly comparable to an average of 88,000 (range 70,000 to 107,000) for 2006 - 2008 for the
Susitna River (upstream of the confluence of the Yentna River; Yanusz et al. 2007, 2011a, b).
Middle River (RM120 / Curry) and Tributaries
Historically, Sockeye Salmon average escapement was 2,400 (range 1,300 to 3,600) for the
Middle River at Talkeetna Station. This is very similar to an average of 2,000 for 2007 - 2008
using the proportion of radio-tags with a destination in the Middle River (2.4 percent of the
Lower River escapement). None of the radio-tags applied in the Lower River in 2012 had a
destination in the Middle River.
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License participants raised the concern as to whether using existing and recent escapement
information (2006 - 2008) in combination with new distribution data in the Middle River (2012 –
2014) as designed in the Study Plan were sufficient to evaluate Sockeye Salmon distribution and
abundance. AEA completed three years of radio-tagging on Sockeye Salmon in the Middle
River, and one year in the Lower River. In combination, these data produced confirming
information of the distribution of sockeye salmon and the recent average abundance estimate
presented above and met the objective of the study.
License participants raised the concern as to whether a contemporary escapement estimate was
not needed for Sockeye Salmon (FERC 2013b). ADFG released a total of 1,524 radio tags in
Sockeye Salmon from 2006-2008 which provided Susitna River basin wide distribution and
abundances (327,732 – 418,197) for each year (Yanusz et al. 2007, 2011a,b). Furthermore,
recent research were consistent with historical data from the 1980’s, as well as AEA studies
which demonstrated the low proportional contribution of Sockeye Salmon to the Middle River
relative to the Susitna River basin.
7. CONCLUSIONS
From 2012 to 2014, the study team completed three consecutive years of adult salmon
escapement studies on the Susitna River. The 2012 Adult Salmon Distribution and Habitat
Utilization Study (AEA 2012) was an AEA-sponsored initiative that successfully met all seven
study objectives and helped to refine the scope and methods of the 2013–2014 studies. The 2013
Salmon Escapement Study (Study 9.7; AEA 2014c) met seven of the eight study objectives
outlined in RSP Section 9.7.1.2 and adopted both of the modifications outlined in FERC’s
February 1 SPD as part of the approved Study Plan. The 2014 Salmon Escapement Study (Study
9.7), as reported herein and earlier by AEA (2014a), successfully met all eight study objectives
as outlined in the Study Plan. The study team has completed all field work, data analysis, and
reporting related to the Salmon Escapement Study (Study 9.7).
8. LITERATURE CITED
AEA. 2012. Revised Study Plan: Susitna-Watana Hydroelectric Project FERC Project No.
14241. December 2012. Prepared for the Federal Energy Regulatory Commission by the
Alaska Energy Authority, Anchorage, Alaska. http://www.susitna-watanahydro.org
/study-plan.
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8.5, Part C. Susitna-Watana Hydroelectric Project, FERC Project No. 14241. June 2014.
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October, 1984. Report No. 6. Alaska Department of Fish and Game, Susitna Hydro
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downstream movement of adult Chinook Salmon in rivers. Fisheries Research 44: 37-46
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using bootstrap and related methods. Biometrics 47:255-268.
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distribution of Susitna River chum Oncorhynchus keta and coho O. kisutch salmon, 2010.
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Cleary, P.M., R.J. Yanusz, J.W. Erickson, D.J. Reed, R.A. Neustel, and N.J. Szarzi (in prep a)
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coho O. kisutch salmon, 2011. Alaska Department of Fish and Game, Fishery Data
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keta and coho O. kisutch salmon, 2012. Alaska Department of Fish and Game, Fishery
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salmon, 2009. Fishery Manuscript Series No. 09-01. Alaska Department of Fish and
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escapement based on the area-under-the-curve method. Can. J. Fish. Aquat. Sci. 49:
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river bottom profiles from a Dual-frequency Identification Sonar (DIDSON). Alaska
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Federal Energy Regulatory Commission (FERC), Office of Energy Projects. 2013a. Study Plan
Determination for the Susitna-Watana Hydroelectric Project. Susitna-Watana
Hydroelectric Project No. 14241-000. Issuance: 20130201-3041.
Federal Energy Regulatory Commission (FERC), Office of Energy Projects. 2013b. Director’s
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000. Issuance: 20130426-3001.
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pp.
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Sciences 61: 103-109.
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Clyde Consultants and Entrix. Final Report to Alaska Power Authority.
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of the American Fisheries Society 90: 490-494.
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Department of Fish and Game Fishery Data Series No. 10-72, Anchorage, Alaska.
Quinn, T.P. 2005. The behavior and ecology of Pacific salmon and trout. University of
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Smith, J.J., M.R. Link, and B.D. Cain. 2005. Development of a long-term monitoring project to
estimate abundance of Chinook Salmon in the Copper River, Alaska, 2001-2004. Alaska
Fishery Research Bulletin 11 (2): 118-134.
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October, 1985. Technical Data Report No. 13, Alaska Department of Fish and Game,
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Columbia River with a dual-frequency identification sonar. North American Journal of
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Anchorage.
Yanusz, R.J., R.A. Merizon, T.M. Willette, D.G. Evans and T.R. Spencer. 2011a. Inriver
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121–125.
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9. TABLES
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Table 4.3-1. Aerial spawner surveys conducted in the Middle and Upper River by location and date, 2014.
River Section Waterbody
Miles
Surveyed
Middle River -Cheechako Creek Susitna 155.9 2.4 14-Jul 19-Jul 26-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Below Impediment 3 Chinook Creek Susitna 160.4 8.7 14-Jul 19-Jul 26-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Middle River -Devil Creek Susitna 164.8 2.5 14-Jul 19-Jul 26-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Above Impediment 3 Fog Creek Susitna 179.3 19.3 14-Jul 19-Jul 25-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Fog Creek Tributary L1 Fog 5.1 7.6 14-Jul 19-Jul 25-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Bear Creek Susitna 184.0 5.7 14-Jul 19-Jul 25-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Bear Creek Tributary R1 Bear 0.8 8.2 14-Jul 19-Jul 25-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Tsusena Creek Susitna 184.4 3.6 15-Jul 19-Jul 25-Jul 31-Jul 6-Aug 12-Aug 18-Aug
Upper River -Deadman Creek Susitna 188.4 0.3 15-Jul 19-Jul 25-Jul 31-Jul 7-Aug 13-Aug 19-Aug
Within Reservoir Watana Creek Susitna 196.9 21.3 15-Jul 20-Jul 25-Jul 1-Aug 7-Aug 13-Aug 19-Aug
Watana Creek Tributary R5 Watana 8.6 8.6 15-Jul 20-Jul 25-Jul 1-Aug 7-Aug 13-Aug 19-Aug
Kosina Creek Susitna 209.2 18.8 15-Jul 20-Jul 25-Jul 1-Aug 7-Aug 12-Aug 18-Aug
Gilbert Creek Kosina 6.2 6 15-Jul NS2 NS2 1-Aug 7-Aug 13-Aug 19-Aug
Tsisi Creek Kosina 7.3 6.4 15-Jul NS2 26-Jul 1-Aug 7-Aug 12-Aug 18-Aug
Tsisi Lake 1 Tsisi 7.2 2.8 NS1 NS1 26-Jul 1-Aug 7-Aug 12-Aug NS1
Tsisi Lake 2 Tsisi 10.6 5.2 NS1 NS1 26-Jul 1-Aug 7-Aug 12-Aug 18-Aug
Jay Creek Susitna 211.0 13.3 15-Jul 20-Jul 26-Jul 1-Aug 7-Aug 13-Aug 19-Aug
Upper River -Goose Creek Susitna 232.9 11.2 15-Jul 20-Jul 26-Jul 1-Aug 7-Aug 13-Aug 19-Aug
Above Reservoir Oshetna River Susitna 235.1 26.3 15-Jul 20-Jul 26-Jul 1-Aug NS2 13-Aug 19-Aug
Black River Oshetna 6.2 15-Jul 20-Jul 26-Jul 1-Aug NS2 13-Aug 19-Aug
1 No survey - surveys targeting Sockeye Salmon began July 25-26.
2 No survey - high and/or turbid water prevented survey.
Confluence
Project River
Mile Survey Dates
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Table 5.1-1. Number of adult salmon radio-tagged in the Susitna River Basin from 2012 to 2014, by species,
fish size, and tagging location.
Tagging Total
Species (and Fish Size)Location 2012 2013 2014 (All Years)
Chinook Salmon (Largea)Lower River 442 580 659 1,681
Yentna River 0 425 296 721
Middle River 352 536 590 1,478
Total (All Locations)794 1,541 1,545 3,880
Chinook Salmon (Smalla)Middle River 0 67 32 99
Chum Salmon Lower River 400 0 0 400
Middle River 279 201 200 680
Total (All Locations)679 268 232 1,179
Coho Salmon Lower River 399 596 658 1,653
Middle River 184 242 212 638
Total (All Locations)583 838 870 2,291
Pink Salmon Lower River 401 197 198 796
Middle River 230 200 201 631
Total (All Locations)631 397 399 1,427
Sockeye Salmon Lower River 100 0 0 100
Middle River 70 139 200 409
Total (All Locations)170 139 200 509
Total (All Species)Lower River 1,742 1,373 1,515 4,630
Yentna River 0 425 296 721
Middle River 1,115 1,385 1,435 3,935
Total (All Locations)2,857 3,183 3,246 9,286
a MEF ≥ 50 cm for large Chinook Salmon; MEF < 50 cm for small Chinook Salmon.
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Table 5.2-1. Classifications for radio-tagged salmon in 2014, by species and release location.
Chinook
(< 50 cm)
Sockeye
Salmon
Chum
Salmon
Classification (PRM)
Lower
River
Middle
River
Yentna
River
Middle
River
Lower
River
Middle
River
Lower
River
Middle
River
Yentna
River
Middle
River
Middle
River
Tributary Destinations (total)574 438 227 20 155 164 565 173 48 76 141
Yentna River (32.4)113 0 219 0 20 1 46 1 43 0 0
Deshka River (44.9)136 0 4 0 24 0 89 0 3 1 0
Willow Creek (52.2)30 0 2 0 13 1 15 0 0 0 0
Little Willow Creek (55.6)22 0 1 0 5 0 15 0 0 0 0
Kashwitna River (64.7)16 1 0 0 5 1 9 1 0 0 0
Caswell Creek (67.4)0 0 0 0 1 0 15 0 0 0 0
Sheep Creek (70.1)6 0 0 0 1 0 4 1 0 0 0
Goose Creek (76.9)3 1 0 0 0 1 10 0 0 0 0
Montana Creek (80.9)16 5 0 0 7 5 11 2 0 0 3
Rabideux Creek (87.4)0 0 0 0 0 0 10 1 0 0 0
Sunshine Creek (88.1)1 0 0 0 0 0 26 4 0 0 0
Birch Creek (93.5)2 1 0 0 1 0 10 3 0 0 0
Trapper Creek (95.0)0 0 0 0 0 1 12 1 0 0 0
Talkeetna River (101.1)89 25 0 1 5 33 88 8 0 41 30
Chulitna River (102.4)109 15 1 0 69 11 172 4 2 25 10
Whiskers Creek (104.8)1 1 0 1 0 11 11 9 0 1 0
Chase Creek (110.5)0 1 0 0 0 0 6 6 0 0 0
Trib 113.7 (113.7)0 0 0 0 0 0 0 1 0 0 0
Slash Creek (114.8)0 0 0 0 0 0 0 2 0 0 0
Gash Creek (115.1)0 0 0 0 0 1 0 4 0 0 0
Lane Creek (117.1)0 3 0 2 0 0 1 4 0 0 0
5th of July Creek (127.3)0 0 0 0 0 1 0 0 0 0 0
4th of July Creek (134.3)0 8 0 0 2 26 0 4 0 0 3
Gold Creek (140.1)0 6 0 0 0 0 0 0 0 0 0
Indian River (141.8)17 182 0 8 2 61 14 98 0 2 49
Jack Long Creek (148.2)0 3 0 0 0 0 0 2 0 1 0
Portage Creek (152.3)12 183 0 8 0 10 1 17 0 5 46
Cheechako Creek (155.9)1 2 0 0 0 0 0 0 0 0 0
Kosina Creek (209.1)0 1 0 0 0 0 0 0 0 0 0
Pink SalmonChinook Salmon (≥ 50 cm)Coho Salmon
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Table 5.2-1. Continued.
Chinook
(< 50 cm)
Sockeye
Salmon
Chum
Salmon
Classification (PRM)
Lower
River
Middle
River
Yentna
River
Middle
River
Lower
River
Middle
River
Lower
River
Middle
River
Yentna
River
Middle
River
Middle
River
Mainstem Destinations (total)7 34 0 4 1 12 16 11 0 66 18
Mainstem Proper 2 4 0 0 1 0 0 2 0 0 2
Downstream of Lane (117.1)2 0 0 0 1 0 0 0 0 0 1
no prior spawn location 2 0 0 0 1 0 0 0 0 0 1
Upstream of Lane (117.1)0 4 0 0 0 0 0 2 0 0 1
no prior spawn location 0 3 0 0 0 0 0 2 0 0 1
was in Portage Creek 0 1 0 0 0 0 0 0 0 0 0
Tributary Mouths 2 22 0 3 0 7 3 3 0 0 5
Trapper Mouth (44.9)0 0 0 0 0 0 1 0 0 0 0
Montana Mouth (80.9)0 0 0 0 0 0 1 0 0 0 0
Rabideux Mouth (87.4)0 0 0 0 0 0 1 0 0 0 0
Talkeetna Mouth (101.0)1 0 0 0 0 0 0 0 0 0 0
Lane Mouth (117.1)0 1 0 0 0 0 0 0 0 0 0
no prior spawn location 0 0 0 0 0 0 0 0 0 0 0
was up Talkeetna River 0 1 0 0 0 0 0 0 0 0 0
5th of July Mouth (127.3)0 3 0 0 0 1 0 0 0 0 1
4th of July Mouth (134.3)0 3 0 0 0 3 0 0 0 0 1
no prior spawn location 0 1 0 0 0 2 0 0 0 0 1
was up 4th of July Creek 0 1 0 0 0 1 0 0 0 0 0
was up Indian River 0 1 0 0 0 0 0 0 0 0 0
Gold Mouth (140.1)0 1 0 0 0 0 0 0 0 0 1
Indian Mouth (141.8)0 10 0 3 0 3 0 2 0 0 1
no prior spawn location 0 8 0 1 0 3 0 2 0 0 1
was up Indian River 0 2 0 2 0 0 0 0 0 0 0
Portage Mouth (152.3)0 4 0 0 0 0 0 1 0 0 1
no prior spawn location 0 2 0 0 0 0 0 0 0 0 1
was up Portage Creek 0 2 0 0 0 0 0 1 0 0 0
Cheechako Mouth (155.9)1 0 0 0 0 0 0 0 0 0 0
Pink SalmonChinook Salmon (≥ 50 cm)Coho Salmon
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Table 5.2-1. Continued.
Chinook
(< 50 cm)
Sockeye
Salmon
Chum
Salmon
Classification (PRM)
Lower
River
Middle
River
Yentna
River
Middle
River
Lower
River
Middle
River
Lower
River
Middle
River
Yentna
River
Middle
River
Middle
River
Side Channels & Sloughs 3 8 0 1 0 5 13 6 0 66 11
Slough 8A (129.2)0 0 0 0 0 0 0 0 0 23 0
Slough 9 (131.4)0 0 0 0 0 0 0 0 0 10 1
Slough 11 (138.6)0 1 0 0 0 0 0 0 0 13 0
no prior spawn location 0 1 0 0 0 0 0 0 0 12 0
was up Portage Creek 0 0 0 0 0 0 0 0 0 1 0
Slough 21 (145.1)0 0 0 0 0 0 0 0 0 0 0
Other areas 3 7 0 1 0 5 13 6 0 20 10
no prior spawn location 3 6 0 1 0 5 11 5 0 20 9
was up Deshka River 0 0 0 0 0 0 2 0 0 0 0
was up Chulitna River 0 0 0 0 0 0 0 0 0 0 1
was up Indian River 0 1 0 0 0 0 0 0 0 0 0
was up Portage Creek 0 0 0 0 0 0 0 1 0 0 0
Other Classifications (total)75 118 68 8 43 25 59 46 12 58 41
Other Mainstem 31 60 4 3 22 17 49 20 0 49 31
Max Zone downstream of Lane 30 0 4 0 22 0 48 0 0 0 0
Max Zone upstream of Lane 1 60 0 3 0 17 1 20 0 49 31
Downstream Only 16 40 46 4 0 4 4 17 6 8 1
Near Release Site 13 17 10 1 20 3 2 8 1 1 7
No or Single Detections 15 1 8 0 1 1 4 1 5 0 2
Total Tags Released 656 590 295 32 199 201 640 230 60 200 200
Notes:
Fish that were detected on several occasions within a limited area were classified with a 'Mainstem Destination' (either in side-channel/slough locations, in a tributary mouth, or in the mainstem proper). Some of the fish
that showed the ‘Mainstem Destination’ detection pattern did so after entering a spawning tributary (those that had at least one live detection in the mainstem location and that spent less than 6 days in the tributary location
are noted in the table – otherwise the mainstem detection was ignored and the fish was assigned to the tributary location). Tags that were recovered or returned were included in this table either under the 'Other
Mainstem' classification (if the recovery date was outside of the range of probable spawning dates) or within the row that was associated with the recovery location (if recoveries were from within a tributary, or were in
a possible mainstem spawning location).
Pink SalmonChinook Salmon (≥ 50 cm)Coho Salmon
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Table 5.2-2. The proportions of radio-tagged salmon of known destination that were detected in the Middle
and Upper rivers, and that subsequently returned downstream to enter a Lower River tributary, or that
appeared to have a mainstem destination in the Lower River, 2014.
Tagged in Lower River
Classification
Chinook
Salmon
Pink
Salmon
Coho
Salmon
Reached Lane Station 37 6 26
Unknown Destination 1 0 1
Known Classification (a)1 36 6 25
Mid/Upper-Susitna Tributary 30 4 15
Mid/Upper-Susitna Mainstem 1 0 0
Returned Downstream (b)1 5 2 10
Lane Creek 0 0 1
Chase Creek 0 0 2
Whiskers Creek 0 0 3
Chulitna River 3 1 3
Talkeetna River 1 1 0
Sunshine Creek 0 0 1
Montana Creek 1 0 0
Proportion Roaming (c)1 13.9%33.3%40.0%
Tagged in Middle River
Classification / Fate
Chinook
Salmon
(≥ 50 cm)
Chinook
Salmon
(< 50 cm)
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
Tagged at Curry 590 32 201 230 200 200
Other Classification (from Table Table 5.2-1)118 8 25 46 58 41
Other Mainstem 60 3 17 20 49 31
Downstream Only 40 4 4 17 8 1
Near Release Site 17 1 3 8 1 7
No / Single Detections 1 0 1 1 0 2
Known Classification (a)1 472 24 176 184 142 159
Tributary above Curry 385 16 98 121 8 98
Susitna Mainstem above Curry 33 3 10 9 65 17
Returned Downstream (b)1 54 5 68 54 69 44
Mainstem Destination 1 1 2 2 1 1
Lane Creek 3 2 0 4 0 0
Gash Creek 0 0 1 4 0 0
Slash Creek 0 0 0 2 0 0
Trib 113.7 0 0 0 1 0 0
Chase Creek 1 0 0 6 0 0
Whiskers Creek 1 1 11 9 1 0
Chulitna River 15 0 11 4 25 10
Talkeetna River 25 1 33 8 41 30
Trapper Creek 0 0 1 1 0 0
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Table 5.2-2. Continued.
Tagged in Middle River
Classification / Fate
Chinook
Salmon
(≥ 50 cm)
Chinook
Salmon
(< 50 cm)
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
Birch Creek 1 0 0 3 0 0
Rabideux Creek 0 0 0 1 0 0
Sunshine Creek 0 0 0 4 0 0
Montana Creek 5 0 5 2 0 3
Sheep Creek 0 0 0 1 0 0
Goose Creek 1 0 1 0 0 0
Kashwitna River 1 0 1 1 0 0
Willow Creek 0 0 1 0 0 0
Deshka River 0 0 0 0 1 0
Yentna River 0 0 1 1 0 0
Proportion Roaming (c)1 11.4%20.8%38.6%29.3%48.6%27.7%
Notes:
1 c = b / a
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Table 5.2-3. Farthest upstream detection locations for radio-tagged fish that were eventually assigned to
mainstem or tributary spawning locations downstream of Lane Station (top panel: fish released in the Lower
River; bottom panel: fish released in the Middle River), 2014. Project river miles are shown in parentheses.
Tagged in Lower River
Farthest Upstream Location
Chinook
Salmon
Pink
Salmon
Coho
Salmon
Lane Station (116.7)2 1 8
Near Curry (124.2)1 0 0
4th of July Ck. Mouth (134.3)0 0 1
Indian R. mouth (141.8)0 0 1
Powerline (145.7)1 0 0
Portage Ck. Mouth (152.3)0 1 0
Below Impediment 1 (155.2)1 0 0
Total number that reached Lane
Station, then were assigned a
downriver destination 5 2 10
Tagged in Middle River
Farthest Upstream Location
Chinook
Salmon
(≥ 50 cm)
Chinook
Salmon
(< 50 cm)
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
Near Curry (124.2)32 3 27 30 41 35
Gateway (130.1)6 2 9 6 5 2
4th of July mouth (134.3)1 0 0 1 0 0
Slough 11 mouth (138.7)0 0 0 1 0 0
Gold Creek mouth (140.1)0 0 0 0 1 0
Indian R. mouth (141.8)8 0 29 10 7 2
Powerline (145.7)1 0 0 1 3 1
Jack Long Ck. Mouth (148.2)0 0 0 0 3 1
Portage Ck. Mouth (152.3)4 0 3 5 6 3
Below Impediment 1 (155.2)2 0 0 0 1 0
Above Impediment 1 (155.2)0 0 0 0 2 0
Total number released in the
Middle River, then were assigned
a downriver destination 54 5 68 54 69 44
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Table 5.3-1. Number of salmon radio-tagged in the Lower and Middle rivers, and the number of radio-
tagged salmon that were detected at or above the Gateway Station, above each impediment, and above the
proposed dam site, 2014.
Radio At or Above Above Above Above Above
Species Tags Gateway Impediment 1 Impediment 2 Impediment 3 Dam Site
Tag Site Applied (PRM 130.1)(PRM 155.2)(PRM 160.2)(PRM 164.8)(PRM 187.1)
Chinook Salmon (Large)
Tagged in Lower River 659 34 2 1 0 0
Tagged in Middle River 590 491 11 8 2 1
Total Tagged 1,249 525 13 9 2 1
Chinook Salmon (Small)
Tagged in Middle River 32 24 0 0 0 0
Chum Salmon
Tagged in Middle River 200 154 0 0 0 0
Coho Salmon
Tagged in Lower River 640 17 0 0 0 0
Tagged in Middle River 230 170 0 0 0 0
Total Tagged 870 187 0 0 0 0
Pink Salmon
Tagged in Lower River 198 5 0 0 0 0
Tagged in Middle River 201 164 0 0 0 0
Total Tagged 399 169 0 0 0 0
Sockeye Salmon
Tagged in Middle River 200 146 3 0 0 0
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Table 5.3-2. Details of the radio-tagged salmon that approached or passed the Middle River impediments, 2014.
Chinook Salmon (≥ 50 cm) that Passed Impediment 3 (PRM 164.4)
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
537 Curry, Site Three 4 Jul 80 Male 20 Jul 20 Jul 4 Aug Just above I3, then mort DS
787 Curry, Site Two 11 Jul 78 Undetermined 20 Jul 20 Jul 30 Jul Kosina (8/2-8/7), Oshetna (8/9), then Kosina (8/12-18),
drfited to below Fog Ck.
Chinook Salmon (≥ 50 cm) that Passed Impediment 2 (PRM 160.2) but not Impediment 3 (PRM 164.4)
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
17 Curry, Site One 14 Jun 70 Undetermined 30 Jun 30 Jun -Below I3, then Cheechako (7/10) then Portage (7/14-
8/6) then mort DS
139 Curry, Site One 21 Jun 61 Undetermined 24 Jul 28 Jul -Cheechako (7/25-26) then mort near Chinook Creek
222 Curry, Site Two 24 Jun 75 Undetermined 6 Jul 18 Jul -Below I3, then mort DS
516 Curry, Site One 4 Jul 87 Undetermined 1 Aug 1 Aug -Cheechako to Chinook mouths, then Cheechako (8/9)
then out, mort at mouth
882 Curry, Site Three 16 Jul 51 Undetermined 25 Jul 1 Aug -Chinook mouth then Cheechako (8/3-9) then mort DS
903 Curry, Site Three 17 Jul 78 Undetermined 23 Jul 24 Jul -Below I3, mort between Chinook and I3
5531 Lower River, gill net 12 Jun 93 n/a 18 Jul 18 Jul -Below I3, then in Cheechako (8/12) and at mouth (8/15-
9/2)
Chinook Salmon (≥ 50 cm) that Passed Impediment 1 (PRM 155.2) but not Impediment 2 (PRM 160.2)
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
221 Curry, Site One 24 Jun 92 Undetermined 20 Jul --Portage (7/10), just Above I1, then Below I1, drifted as
mort DS
828 Curry, Site Three 13 Jul 55 Undetermined 18 Jul --Cheechako Stn, then Portage
868 Curry, Site Three 15 Jul 94 Male 23 Jul --Cheechako (7/31-8/1 and 8/6-8/12), mouth (to 8/18)
then drifted DS to below Portage
5702 Lower River, gill net 23 May 91 n/a 1 Jul --0.75 mi above Cheechako Stn, then in Cheechako
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Table 5.3-2. Continued.
Chinook Salmon (≥ 50 cm) that Approached Impediment 1 (PRM 155.2) but did not Pass
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
23 Curry, Site Two 14 Jun 63 Undetermined ---Below I1, Portage (7/25-8/4), then mort DS
33 Curry, Site Two 15 Jun 63 Undetermined ---Below I1, then Talkeetna
40 Curry, Site Two 16 Jun 68 Undetermined ---Below I1, then Portage
91 Curry, Site Three 19 Jun 92 Undetermined ---Below I1, then Portage
103 Curry, Site One 20 Jun 81 Undetermined ---mort Below I1
108 Curry, Site Two 20 Jun 99 Undetermined ---Below I1, Portage (7/22-23) then DS
111 Curry, Site Three 20 Jun 97 Undetermined ---Portage (7/4-7/5), Below I1, Portage (7/19-onwards)
166 Curry, Site One 22 Jun 63 Undetermined ---
Below I1, Portage (7/14), Portage mouth (7/22-8/4),
mort DS
198 Curry, Site One 23 Jun 78 Undetermined ---Below I1, then Talkeetna
237 Curry, Site One 25 Jun 93 Male ---Below I1, Indian (7/22-8/6) then DS
239 Curry, Site One 25 Jun 87 Female ---Below I1, then Portage
244 Curry, Site Two 25 Jun 84 Undetermined ---
Below I1, then Portage (mid-Aug onward, incl mort
8/20)
264 Curry, Site One 28 Jun 78 Undetermined ---Below I1, then Gold Creek
300 Curry, Site One 29 Jun 66 Undetermined ---Portage mouth , Below I1, then up Portage
359 Curry, Site Three 30 Jun 59 Undetermined ---Below I1, then mort DS
562 Curry, Site One 5 Jul 79 Undetermined ---Below I1, then Portage
611 Curry, Site Three 5 Jul 91 Undetermined ---Below I1, then Portage
621 Curry, Site One 6 Jul 87 Undetermined ---Below I1, then Portage
668 Curry, Site Three 6 Jul 80 Undetermined ---Below I1, then Portage
716 Curry, Site One 8 Jul 95 Undetermined ---Below I1, then mort DS
818 Curry, Site Two 13 Jul 64 Undetermined ---Below I1, then Indian (7/26-8/5) then mort DS of mouth
5242 Lower River, East Bank 4 Jun 75.5 n/a ---Chulitna, Below I1, then Chulitna
5255 Lower River, East Bank 7 Jun 83 n/a ---Deshka, Below I1, then Portage
5384 Lower River, West Bank 17 Jun 73.5 n/a ---Below I1, then mort DS
5408 Lower River, gill net 31 May 93 n/a ---Below I1, then Portage
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Table 5.3-2. Continued.
Chinook Salmon (< 50 cm) that Approached Impediment 1 (PRM 155.2) but did not Pass
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
574 Curry, Site One 5 Jul 41 Undetermined ---Below I1, Portage (7/25-8/4), then Indian (8/9), then
back to Portage (8/15-onwards)
Sockeye Salmon That Passed Impediment 1 (PRM 155.2) but not Impediment 2 (PRM 160.2)
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
785 Curry, Site Two 11 Jul 48 Undetermined 27 Jul --
Cheechako Stn, dropback, held below I1, moved into
Jack Long (9/5), then mort DS
955 Curry, Site Three 19 Jul 49 Undetermined 8 Sep --
Detected above I1 for a single survey (9/8), then
moved into Chulitna
2214 Curry, Site Three 8 Aug 45 Undetermined 8 Sep --
Chulitna (8/13-19), moved above I1 for a single survey
(9/8), then wandered
Sockeye Salmon That Approached Impediment 1 (PRM 155.2) but did not Pass
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
647 Curry, Site Two 6 Jul 60 Undetermined ---Below I1, then mort DS
837 Curry, Site Two 14 Jul 47 Undetermined ---Below I1, then mort DS
1053 Curry, Site One 23 Jul 46 Undetermined ---
Portage (1 survey), Below I1, then Side-channel
outside Slough 21
1260 Curry, Site Three 26 Jul 48 Undetermined ---
Below I1 four times interspersed by wandering, then
mort DS
1293 Curry, Site Two 27 Jul 55 Undetermined ---Below I1, then Talkeetna
1346 Curry, Site Two 28 Jul 45 Undetermined ---Below I1 , then mort DS
1404 Curry, Site Two 29 Jul 43 Undetermined ---Below I1 , then mort DS
1851 Curry, Site Two 4 Aug 54 Female ---Below I1 , then mort DS
2076 Curry, Site Two 7 Aug 45 Undetermined ---Below I1, then into 4th of July Slough
2156 Curry, Site One 8 Aug 42 Undetermined ---Below I1 , then mort DS
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Table 5.3-2. Continued.
Sockeye Salmon That Approached Impediment 1 (PRM 155.2) but did not Pass
Tag
Number Capture/ Release Site
Capture
Date
METF
Length
(cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
2157 Curry, Site One 8 Aug 45 Undetermined ---Below I1, Portage, Below I1, Side Channel 21
2606 Curry, Site One 13 Aug 51 Undetermined ---
Below I1 three times interspersed by wandering, then
mort DS
2770 Curry, Site One 15 Aug 53 Male ---
Below I1 twice interspersed by wandering, the Side
Channel 21
Notes:
Fish characteristics include 'tag numbers' (unique numbers assigned to each individual radio-tagged fish), capture and release site, capture date, METF (mid-eye to fork length, in cm) and sex.
Tracking details include the date of first detections above each impediment, and a comment about the general movments of the fish. Top panel: Chinook salmon (≥ 50 cm) that passed Impediment
3. Second panel: Chinook salmon (≥ 50 cm) that passed Impediment 2, but not Impediment 3. Third panel: Chinook salmon (≥ 50 cm) that passed Impediment 1, but not Impediment 2. Fouth
panel: Chinook salmon (≥ 50 cm) that approached within 1 km of Impediment 1, but did not pass. Fifth panel: Chinook salmon (< 50 cm) that approached within 1 km of Impediment 1, but did not
pass. Fifth panel: Chinook salmon (< 50 cm) that approached within 1 km of Impediment 1, but did not pass. Sixth panel: Sockeye salmon that passed Impediment 1, but not Impediment 2.
Seventh panel: Sockeye salmon that approached within 1 km of Impediment 1, but did not pass.
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Table 5.3-3. Destinations of radio-tagged salmon that passed each Middle River impediment, 2014.
Sockeye
Salmon
Passed I1
but not I2
Passed I2
but not I3 Passed I3 Total
Passed I1
but not I2
Grand
Total
Classification
Tributary Destinations
Chulitna River 2 2
Jack Long Creek 1 1
Portage Creek 1 1 2 2
Cheechako Creek 2 1 3 3
Kosina Creek 1 1 1
Mainstem Destinations
Mouth of Cheechako 1 1 1
Unknown Destination 1 4 1 6 6
Total 4 7 2 13 3 16
Downstream from Impediment
Number 1 3 0 4 3 7
Percent 33%100%0%57%100%70%
Notes:
An “I” refers to “impediment.” Shaded cells refer to areas that are located downstream of the impediment in question.
Chinook Salmon (≥ 50 cm)
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Table 5.3-4. Dates on which radio-tagged fish were first detected upstream of Impediment 3 (2012-2014), with corresponding flows as measured at
Tsusena and Gold creeks.
Flow at I-1
Passage (cfs)
Flow at I-2
Passage (cfs)
Flow at I-3
Passage (cfs)
Flow at I-1
Passage (cfs)
Flow at I-2
Passage (cfs)
Flow at I-3
Passage (cfs)
Chinook Salmon (≥ 50 cm) that Passed Impediment 3 in 2012
27 15 Jul 2012 16 Jul 2012 18 Jul 2012 15,800 16,500 15,200 18,608 19,252 17,774
52 7 Jul 2012 7 Jul 2012 17 Jul 2012 17,800 17,800 15,800 21,302 21,302 19,042
94 8 Jul 2012 12 Jul 2012 17 Jul 2012 20,800 16,400 15,800 26,550 20,060 19,042
104 18 Jul 2012 18 Jul 2012 20 Jul 2012 15,200 15,200 15,000 17,774 17,774 17,320
113 15 Jul 2012 15 Jul 2012 19 Jul 2012 15,800 15,800 14,900 18,608 18,608 17,407
219 15 Jul 2012 16 Jul 2012 19 Jul 2012 15,800 16,500 14,900 18,608 19,252 17,407
246 13 Jul 2012 14 Jul 2012 20 Jul 2012 15,600 15,500 15,000 18,755 18,275 17,320
257 15 Jul 2012 16 Jul 2012 20 Jul 2012 15,800 16,500 15,000 18,608 19,252 17,320
266 15 Jul 2012 16 Jul 2012 19 Jul 2012 15,800 16,500 14,900 18,608 19,252 17,407
359 12 Jul 2012 12 Jul 2012 17 Jul 2012 16,400 16,400 15,800 20,060 20,060 19,042
5005 17 Jul 2012 17 Jul 2012 17 Jul 2012 15,800 15,800 15,800 19,042 19,042 19,042
5019 9 Jul 2012 17 Jul 2012 18 Jul 2012 24,600 15,800 15,200 31,067 19,042 17,774
Chinook Salmon (≥ 50 cm) that Passed Impediment 3 in 2013
241 13 Jul 2013 14 Jul 2013 16 Jul 2013 14,383 15,410 16,672 16,178 18,233 18,632
272 13 Jul 2013 14 Jul 2013 30 Jul 2013 14,383 15,410 18,848 16,178 18,233 19,657
395 11 Jul 2013 12 Jul 2013 13 Jul 2013 16,876 15,058 14,383 20,272 17,985 16,178
Chinook Salmon (≥ 50 cm) that Passed Impediment 3 in 2014
537 20 Jul 2014 20 Jul 2014 4 Aug 2014 21,400 21,400 16,400 25,900 25,900 19,200
787 20 Jul 2014 20 Jul 2014 30 Jul 2014 21,400 21,400 15,900 25,900 25,900 19,400
Gold CreekTsusena CreekFirst
Detection
Above I-3
First
Detection
Above I-2
First
Detection
Above I-1
Tag
Number
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Table 5.3-5. Aerial Chinook Salmon spawning escapement surveys. Number of flights, and date and magnitude of peak counts per stream and survey
year. The number of radio-tagged Chinook Salmon that were classified to each stream (see Table 5.2-1) is included for 2012-2014.
Stream # FlightsDate of Peak CountPeak Count# FlightsDate of Peak CountPeak Count# FlightsDate of Peak CountPeak Count# FlightsDate of Peak CountPeak CountCheechako Cr 9 6 Aug 16 2 1 Aug 25 7 1 Aug 29 11 24 Jul 18
Chinook Cr 5 6 Aug 5 2 1 Aug 8 7 1 Aug 15 11 23 Aug 1
Devil Cr 5 na 0 1 1 Aug 1 6 na 0 11 na 0
Fog Cr 0 0 4 21 Jul 2 3 na 0
Bear Cr 0 0 4 na 0 3 na 0
Tsusena Cr 0 0 4 na 0 3 na 0
Deadman Cr 0 0 3 na 0 0
Watana Cr 0 0 2 na 0 0
Kosina Cr 0 0 0 0
Jay Cr 0 0 0 0
Goose Cr 0 0 0 0
Oshetna Cr 0 0 0 0
19831982 19851984
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Table 5.3-5. Continued.
Stream # FlightsDate of Peak CountPeak CountClassified Radio-tagged Fish# FlightsDate of Peak CountPeak CountClassified Radio-tagged Fish# FlightsDate of Peak CountPeak CountClassified Radio-tagged FishCheechako Cr 4 30 Jul 5 6 5 26 Jul 40 6 6 19 Jul 16 3
Chinook Cr 4 5 Aug 5 3 5 26 Jul 2 1 6 19/25 Jul 5 0
Devil Cr 4 5 Aug 7 1 5 26 Jul 25 1 6 6 Aug 10 0
Fog Cr 4 30 Jul 1 0 5 9/15 Aug 2 0 6 31 Jul 3 0
Bear Cr 4 na 0 0 5 na 0 0 6 na 0 0
Tsusena Cr 4 na 0 0 5 9 Aug 4 1 6 na 0 0
Deadman Cr 4 na 0 0 5 na 0 0 6 na 0 0
Watana Cr 4 na 0 0 5 na 0 0 6 na 0 0
Kosina Cr 4 5 Aug 16 6 5 26 Jul 3 0 6 na 0 1
Jay Cr 4 na 0 0 5 na 0 0 6 na 0 0
Goose Cr 4 na 0 0 5 na 0 0 6 na 0 0
Oshetna Cr 4 na 0 0 5 na 0 0 5 na 0 0
2012 2013 2014
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Table 5.4-1. Survey effort and observations using DIDSON to identify Chinook Salmon spawning behavior in turbid water, 2014.
Date Sample Location Latitiude Longitude
DIDSON
Used
Chinook
Observed
Spawning
Observed
Redds
Observed Comments
19-Jul Gateway Slough 62.67643 -149.89302 Yes No --
19-Jul Mainstem gravel bar, d/s PRM 133 62.70674 -149.84082 No No --
19-Jul 4th of July Slough (60 m u/s of outlet)62.71587 -149.80301 Yes No --
19-Jul Mainstem side channel, PRM 135.5 62.72485 -149.75978 No No --Inaccessible by boat
19-Jul Slough 10 62.73838 -149.74134 No No --No potential sampling
sites
19-Jul Slough 11 62.74281 -149.72163 No No --Inaccessible by boat
20-Jul Slough ?1 "Hidden Slough"62.58162 -150.04994 Yes No --
20-Jul Side channel, near PRM 117 62.53213 -150.10708 Yes No --Entrained air and river
velocity precluded
usable sonar imagery
20-Jul Mainstem d/s 4th of July Creek mouth 62.71481 -149.80823 Yes Yes No No Individuals observed
milling/holding
20-Jul 4th of July Slough (30 m u/s of outlet)62.71558 -149.80345 No No --
20-Jul 4th of July Slough (100 m u/s outlet)62.71701 -149.80208 No No --Large cobble substrate
21-Jul Portage Creek mouth, river right 62.83034 -149.38153 No No --
21-Jul Mainstem d/s Portage Cr. mouth, river right 62.83035 -149.38403 Yes Yes No No Individuals observed
milling/holding
21-Jul Mainstem d/s Portage Cr. mouth, river right 62.83116 -149.38715 No No --
21-Jul Mainstem u/s Jack Long Cr. mouth, river left 62.82270 -149.49220 No No --Sand substrate
21-Jul Mainstem u/s Jack Long Cr. mouth, river left 62.82264 -149.49434 No No --Large cobble substrate
21-Jul Mainstem d/s Jack Long Cr. mouth, river left 62.82243 -149.49821 Yes Yes Yes Yes Individual observed
guarding and holding
21-Jul Mainstem d/s Jack Long Cr. mouth, river left 62.82150 -149.50507 Yes No --
21-Jul Mainstem d/s Gold Cr. mouth, river left 62.76779 -149.69141 No No --
21-Jul Mainstem d/s Sherman Cr. mouth, river left 62.7131 -149.81103 No No --
21-Jul Mainstem d/s Skull Cr. mouth, river left 62.67699 -149.86920 No No --
22-Jul Side channel entrance u/s Indian R., river right 62.79191 -149.62464 No No --Areas of upwelling
22-Jul Side channel exit u/s Indian R., river right 62.78956 -149.63977 No No --
22-Jul Mainstem below side channel, river right 62.78861 -149.64438 No No --Sand substrate
22-Jul Mainstem at Beaver impoundment exit, river right 62.78752 -149.65044 No No --
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Table 5.4-1. Continued.
Date Sample Location Latitiude Longitude
DIDSON
Used
Chinook
Observed
Spawning
Observed
Redds
Observed Comments
22-Jul Mainstem d/s Indian R. delta (10 m), river right 62.78514 -149.65891 Yes Yes No No Individuals observed
milling/holding
22-Jul Mainstem d/s Indian R. delta, over flow channel, river
right
62.78413 -149.66248 No No --
22-Jul Mainstem d/s Indian R. slough entrance 62.78296 -149.66805 Yes Yes No No Individuals observed
milling/holding
22-Jul Mainstem d/s Indian R., river right 62.78145 -149.67789 No No --
22-Jul Mainstem d/s Indian R. slough exit 62.77943 -149.68706 Yes No --
23-Jul Slough u/s Gold Cr., river left 62.77146 -149.68672 No No --Sand and large cobble
substrate
23-Jul Mainstem d/s Gold Cr., river right 62.76829 -149.69449 No No --
23-Jul Mainstem d/s Gold Cr., river right 62.76650 -149.71121 Yes Yes No No Traveling u/s observed
23-Jul Mainstem channel d/s Curry unnamed tributary delta,
river right
62.59989 -150.03344 No No --
25-Jul Confirmation: d/s Portage Cr Mouth 62.83044 -149.38871 Yes Yes No No Individuals observed
milling/holding
25-Jul Confirmation: d/s Jack Long Cr Mouth 62.82243 -149.49821 Yes Yes No No Individual observed
milling/holding
25-Jul Confirmation: d/s 4th of July Cr Mouth 62.71475 -149.80908 Yes Yes No Yes Individual observed
milling/holding
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Table 6.2-1. Confirmed spawning salmon in slough habitats of the Middle River from 1981 to 1985, and
confirmed spawning locations in 2012, 2013, and 2014.
Project
River
Slough Mile 2012 2013 2014 2012 2013 2014 2012 2013 2014 2012 2013 2014
1 103.2 X X
2 104.3 X X X
3B 105.5 X X X X X
3A 105.7 X X X
4 108.9
5 111.3 X X X
6 111.9
6A 115.9 X X X
7 116.6
8 117.2 X X X
Bushrod 117.8 X X
8D 125.2 X X
8C 125.2 X X X
8B 125.7 X X X
Moose 126.7 X X X
A'128.0 X X
A 128.3 X X X
8A 129.5 X X X X X X X X X X X
B 130.0 X X X
9 131.7 X X X X X X X X
9B 132.5 X X
9A 136.3 X X X X X X
10 137.1 X X X X X
11 138.7 X X X X X X X X X
12 138.2
13 138.9 X X X
14 139.4 X
15 140.6 X X X
16 141.1 X X
Confirmed Spawning
Coho Salmon
(1981-1985)
Confirmed Spawning
Chum
Salmon
Coho
Salmon
Pink
Salmon
Sockeye
Salmon
Sockeye SalmonChum Salmon Pink Salmon
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Table 6.2-1. Continued.
Project
River
Slough Mile 2012 2013 2014 2012 2013 2014 2012 2013 2014 2012 2013 2014
17 142.3 X X X
18 142.5 X -
19 143.2 X X X X X X
20 143.6 X X X
21 145.2 X X X X X X X X X
22 147.6 X X X X X
21A 148.6 X X
Note:
Historic data (1981 - 1985) was synthesized from Barrett et al. (1985) and Thompson et al. (1986)
Results from 2012 - 2014 also include some confirmed spawning locations provided by R2USA
(1981-1985) Confirmed Spawning
Chum
Salmon
Coho
Salmon
Pink
Salmon
Sockeye
Salmon
Chum Salmon Coho Salmon Pink Salmon Sockeye Salmon
Confirmed Spawning
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10. FIGURES
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Figure 3-1. Susitna River watershed showing fish capture sites (fishwheels) and the locations of fixed-station telemetry receiver sites, 2014.
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Figure 3-1 (cont). Susitna River watershed showing fish capture sites (fishwheels) and the locations of fixed-station telemetry receiver sites, 2014.
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Figure 4.1-1. Middle River Segment showing sites for fish capture (Site 1, PRM 124.1; Site 2, PRM 123.0;
and Site 3, PRM 126.0), sonar (ARIS; PRM 124.0), Curry camp (PRM 124.2), and the Lane Creek (PRM
116.7) and ‘Gateway’ (PRM 130.1) fixed-station receiver sites, 2014.
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Figure 4.3-1. Extent of aerial spawner surveys in the Indian River and tributaries in and above Devils Canyon, 2014.
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Figure 5.1-1. Daily discharge of the Susitna River at the Gold Creek gauge from April to November in 2012,
2013, and 2014. Historical (1949-2011) median, and 10th and 90th percentile discharges are shown for
reference. Source: USGS National Water Information System (http://waterdata.usgs.gov/nwis).
Figure 5.1-2. Daily discharge of the Susitna River at the Tsusena Creek gauge from April to November in
2012, 2013, and 2014. Source: USGS National Water Information System (http://waterdata.usgs.gov/nwis).
0
15,000
30,000
45,000
60,000
75,000
90,000
4-14-114-215-15-115-215-316-106-206-307-107-207-308-98-198-299-89-189-2810-810-1810-2811-711-1711-27Discharge (cfs)Date (m/d)
2014 2013 2012 10/90th Percentiles (1949-2011)Median (1949-2011)
Susitna at
Gold Creek
0
15,000
30,000
45,000
60,000
75,000
4-14-114-215-15-115-215-316-106-206-307-107-207-308-98-198-299-89-189-2810-810-1810-2811-711-1711-27Discharge (cfs)Date (m/d)
2014
2013
2012
Susitna at
Tsusena Creek
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Figure 5.1-3. Median travel speeds of radio-tagged fish in four major river reaches, by species. Error bars
represent 95% confidence in the median value (generated using the method recommended in Zar 1984).
Statistical comparisons (see text) were done using Kruskal-Wallis tests; overlapping error bars do not
preclude statistical significance.
0 5 10 15 20 25 30 35
Chinook salmon
Chum salmon
Coho salmon
Pink salmon
Sockeye salmon
Travel Speed (km/d)
Gateway to Indian
Curry to Gateway
Sunshine to Lane
Deshka to Sunshine
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Figure 5.2-1. Classifications for radio-tagged salmon released in the Lower River (left panels) or Middle
River (right panels), by species/life history stage, 2014. Top panels: Relative use of tributary and mainstem
destinations, shown as a percentage of the total number of fish that were classified to a destination. Middle
Panels: Relative use of mainstem habitats (side-channel/slough locations, tributary mouths, and the mainstem
proper), shown as a percentage of the total number of fish that were classified with a 'Mainstem Destination'.
Bottom Panel: Relative use of various sloughs and side-channel locations, shown as a percentage of the total
number of fish that were classified with a 'Side-channel/Slough Mainstem Destination'. See text and Table
5.2-1 for more detailed classifications.
0%
20%
40%
60%
80%
100%
Chinook
Salmon
Pink
Salmon
Coho
SalmonRelative FrequencyTributary Mainstem
General Classification
Releases from Lower River
0%
20%
40%
60%
80%
100%
Chinook
Salmon
Pink
Salmon
Coho
SalmonRelative FrequencyMainstem Proper Tributary Mouths Side-channel / Sloughs
Mainstem Use
Releases from
Lower
River
0%
20%
40%
60%
80%
100%
Chinook
(≥ 50 cm)
Chinook
(< 50 cm)
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
General Classification
Releases from Middle River
0%
20%
40%
60%
80%
100%
Chinook
(≥ 50 cm)
Chinook
(< 50 cm)
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
Mainstem Use
Releases from Middle River
0%
20%
40%
60%
80%
100%
Chinook
(≥ 50 cm)
Chinook
(< 50 cm)
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
SalmonRelative FrequencySlough 8A
Slough 9
Slough 11
Slough 21
Side-channels
Side -channel / Slough Use -Releases from Middle River
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Figure 5.2-2. Relative frequencies of tributary use by radio-tagged salmon released in the Lower River, by
species, 2014. Shown as a percentage of all fish classified to a tributary destination. Shown as a percentage of
all fish classified to a tributary destination.
Relative Frequency0%
10%
20%
30%
40%
50%Pink Salmon
0%
10%
20%
30%
40%
50%YentnaDeshkaWillowLittle WillowKashwitnaCaswellGooseSheepMontanaSunshineBirchRabideuxTrapperTalkeetnaChulitnaWhiskersChaseLane4th of JulyIndianPortageCheechakoKosinaOtherStock
Coho Salmon
0%
10%
20%
30%
40%
50%
Chinook Salmon
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Figure 5.2-3. Relative frequencies of tributary use by radio-tagged salmon released in the Middle River, by
species, 2014.hown as a percentage of all fish classified to a tributary destination.
Relative Frequency0%
15%
30%
45%
60%Chinook Salmon (≥ 50 cm)
0%
15%
30%
45%
60%Coho Salmon
0%
15%
30%
45%
60%Chinook Salmon (< 50 cm)
0%
15%
30%
45%
60%Pink Salmon
0%
15%
30%
45%
60%MontanaTalkeetnaChulitnaOther Lower SuWhiskersChaseTrib 113.7SlashGashLane5th of July4th of JulyGoldIndianJack LongPortageCheechakoKosinaStock
Chum Salmon
0%
15%
30%
45%
60%Sockeye Salmon
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Figure 5.3-1. Daily numbers of radio-tagged large Chinook Salmon that approached and passed each of the
three Middle River impediments in 2014. Orange bars: fish that approached but did not pass. Blue bars:
fish that approached and successfully passed. Figures show the date of first detection above the impediment
(blue) or the date of first detection below the impediment (orange). Also shown is the average daily flow of
the Susitna River as measured at the Tsusena Creek gauge. An “I” refers to “Impediment.”
0
1
2
3
4
5
6
7
8
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
6/10 6/13 6/16 6/19 6/22 6/25 6/28 7/1 7/4 7/7 7/10 7/13 7/16 7/19 7/22 7/25 7/28 7/31 8/3 8/6 8/9 8/12 8/15 8/18 8/21 8/24 8/27 8/30 9/2 9/5 9/8 9/11Number of Fish at I1Tsusena Discharge (cfs)Date (m/d)
Chinook Salmon (≥ 50 cm)
Impediment 1 (PRM 155.2)
0
1
2
3
4
5
6
7
8
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
6/10 6/13 6/16 6/19 6/22 6/25 6/28 7/1 7/4 7/7 7/10 7/13 7/16 7/19 7/22 7/25 7/28 7/31 8/3 8/6 8/9 8/12 8/15 8/18 8/21 8/24 8/27 8/30 9/2 9/5 9/8 9/11Number of Fish at I3Tsusena Discharge (cfs)Passed
Approached (did not pass)
Chinook Salmon (≥ 50 cm)
Impediment 3 (PRM 164.4)
0
1
2
3
4
5
6
7
8
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
6/10 6/13 6/16 6/19 6/22 6/25 6/28 7/1 7/4 7/7 7/10 7/13 7/16 7/19 7/22 7/25 7/28 7/31 8/3 8/6 8/9 8/12 8/15 8/18 8/21 8/24 8/27 8/30 9/2 9/5 9/8 9/11Number of Fish at I2Tsusena Discharge (cfs)Chinook Salmon (≥ 50 cm)
Impediment 2 (PRM 160.2)
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Figure 5.3-2. Daily numbers of radio-tagged small Chinook (top panel) and Sockeye (bottom panel) salmon
that approached and passed Middle River Impediment 1 in 2014. Orange bars: fish that approached but did
not pass. Blue bars: fish that approached and successfully passed. Figures show the date of first detection
above the impediment (blue) or the date of first detection below the impediment (orange). Also shown is the
average daily flow of the Susitna River as measured at the Tsusena Creek gauge. An “I” refers to
“Impediment.” No Chinook Salmon measuring less than 50 cm (19.7 in) METF or Sockeye Salmon
approached or passed Impediment 2 or Impediment 3.
0
1
2
3
4
5
6
7
8
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
6/10 6/13 6/16 6/19 6/22 6/25 6/28 7/1 7/4 7/7 7/10 7/13 7/16 7/19 7/22 7/25 7/28 7/31 8/3 8/6 8/9 8/12 8/15 8/18 8/21 8/24 8/27 8/30 9/2 9/5 9/8 9/11Number of Fish at I1Tsusena Discharge (cfs)Date
Approached (did not pass)
Passed
Sockeye Salmon
Impediment 1 (PRM 155.2)
0
1
2
3
4
5
6
7
8
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
6/10 6/13 6/16 6/19 6/22 6/25 6/28 7/1 7/4 7/7 7/10 7/13 7/16 7/19 7/22 7/25 7/28 7/31 8/3 8/6 8/9 8/12 8/15 8/18 8/21 8/24 8/27 8/30 9/2 9/5 9/8 9/11Number of Fish at I1Tsusena Discharge (cfs)Date
Approached (did not pass)
Passed
Chinook Salmon (< 50 cm)
Impediment 1 (PRM 155.2)
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Figure 5.3-3. Daily number of radio-tagged Chinook Salmon that held below Impediment 3 in 2014. Each of
the two fish is shown using a unique color. Passage dates can be read by noting the date after which each of
the tags disappears from the chart. Also shown is the average daily flow of the Susitna River as measured at
the Tsusena Creek gauge.
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
0
1
2
3
6/21 6/23 6/25 6/27 6/29 7/1 7/3 7/5 7/7 7/9 7/11 7/13 7/15 7/17 7/19 7/21 7/23 7/25 7/27 7/29 7/31 8/2 8/4 8/6Tsusena Discharge (cfs)Radio-tagged Large Chinook SalmonDate
Tag 787
Tag 537
Flow
Chinook Salmon (≥ 50 cm)that Passed Impediment 3 (PRM 164.4)
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Figure 5.3-4. Flows (measured at Gold Creek) in 2012, 2013 and 2014, along with median (solid black line),
and the 10th and 90th percentile (dotted lines) historical flows. Plotted along the flow curves are passage
events (yellow dots), where the dot size is scaled to indicate the number of fish that passed. Passage events
and corresponding discharge are presented in Table 5.3-4.
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
50,000
55,000
1-Jun8-Jun15-Jun22-Jun29-Jun6-Jul13-Jul20-Jul27-Jul3-Aug10-Aug17-Aug24-Aug31-AugGold Creek Discharge (cfs)Chinook Salmon Passage at Devils Canyon Impediment 1
2012 2013 2014
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
50,000
55,000
1-Jun8-Jun15-Jun22-Jun29-Jun6-Jul13-Jul20-Jul27-Jul3-Aug10-Aug17-Aug24-Aug31-AugGold Creek Discharge (cfs)Chinook Salmon Passage at Devils Canyon Impediment 2
2012 2013 2014
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
50,000
55,000
1-Jun8-Jun15-Jun22-Jun29-Jun6-Jul13-Jul20-Jul27-Jul3-Aug10-Aug17-Aug24-Aug31-AugGold Creek Discharge (cfs)Chinook Salmon Passage at Devils Canyon Impediment 3
2012 2013 2014
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Figure 5.7-1. Destinations for radio-tagged Chinook Salmon released in the Lower River in 2013.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination. Data from Table 5.2-1
in the ISR. Proportions are calculated from the total numbers of tags released, after excluding fish with one
or fewer detections, that never moved, or moved only downstream.
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Figure 5.7-2. Destinations for radio-tagged Chinook Salmon released in the Lower River in 2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination. Data from Table 5.2-1.
Proportions are calculated from the total numbers of tags released, after excluding fish with one or fewer
detections, that never moved, or moved only downstream.
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Figure 5.7-3. Destinations for radio-tagged Coho Salmon released in the Lower River in 2013 (yellow circles).
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination. Data from Table 5.2-1
in the ISR. Proportions are calculated from the total numbers of tags released, after excluding fish with one
or fewer detections, that never moved, or moved only downstream.
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Figure 5.7-4. Destinations for radio-tagged Coho Salmon released in the Lower River in 2014 (yellow circles).
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination. Data from Table 5.2-1.
Proportions are calculated from the total numbers of tags released, after excluding fish with one or fewer
detections, that never moved, or moved only downstream.
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Appendix A: Fish Capture and Tagging
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Table A-1. Number of salmon caught and radio-tagged at two fishwheel sites and from gillnets in the Lower
River, PRM 33.4–34.2, 2014.
Table A-2. Number of Chinook Salmon caught and radio-tagged at fishwheel sites and in gillnets in the
Yentna River (RM 6 and RM 18), 2014.
Radio Tag
Species Target West Bank East Bank Gillnet Total
Chinook Salmon Caught 921 959 168 2,048
Tagged2 700 259 271 129 659
Chum Salmon Caught 2,295 4,282 0 6,577
Coho Salmon Caught 910 603 0 1,513
Tagged 600 337 303 640
Pink Salmon Caught 10,063 3,871 0 13,934
Tagged 200 106 92 198
Sockeye Salmon Caught 396 453 4 853
Total Caught 14,585 10,168 172 24,925
(all species)Tagged 1,500 702 666 129 1,497
1 Total caught includes all adult salmon regardless of size, as well as all recaptured fish.
2 Adult fish measuring 50 cm METF or greater.
FishwheelCaught1/
Tagged
South North Gillnet Total
Yentna River (RM 6)Caught 1,213 1,413 399 3,025
Tagged2 300 95 95 106 296
East West
Yentna River (RM 18)Caught 1,440 743 122 2,305
1 Total caught includes all adult salmon regardless of size, as well as all recaptured fish.
2 All tagged Chinook Salmon measured 50 cm METF or greater.
Radio Tag
Target
FishwheelCaught1/
TaggedLocation
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Table A-3. Number of salmon radio-tagged at three fishwheel sites and in gillnets in the Middle River, by size category, 2014.
Species Large Small Total Large Small Total Large Small Total Large Small Total Large Small Total
Chinook Salmon 247 17 264 75 2 77 268 13 281 0 0 0 590 32 622
Chum Salmon 60 0 60 53 0 53 87 0 87 0 0 0 200 0 200
Coho Salmon 73 0 73 14 0 14 125 0 125 18 0 18 230 0 230
Pink Salmon 73 0 73 27 0 27 101 0 101 0 0 0 201 0 201
Sockeye Salmon 54 0 54 89 0 89 57 0 57 0 0 0 200 0 200
Total 507 17 524 258 2 260 638 13 651 18 0 18 1,421 32 1,453
Notes:
Large Chinook Salmon measured 50 cm METF or greater; and large Chum, Coho, Pink, and Sockeye salmon measured 40 cm METF or greater.
Fishwheels
Gill Net All Gear CombinedSite 1 (PRM 124.1)Site 2 (PRM 123.0)Site 3 (PRM 126.0)
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Table A-4. Number of salmon caught in the Lower River and Yentna River and their length statistics, 2014.
Location Total
Species Name Catch Min Max Mean n
Lower River
Chinook Salmon (≥ 50 cm)a 1,471 50.0 105.0 67.6 1,431
Chinook Salmon (< 50 cm)a 577 27.0 49.5 39.1 561
Total Chinook Salmon 2,048
Chum Salmon 6,577 ----
Coho Salmon 1,513 28.0 68.0 52.5 1,361
Pink Salmon 13,934 40.0 56.5 44.8 198
Sockeye Salmon 849 32.4 69.0 49.3 592
Yentna River (RM 6)
Chinook Salmon (≥ 50 cm)a 1,357 50.0 109.0 66.9 1,355
Chinook Salmon (< 50 cm)a 1,668 21.5 49.5 34.9 1,666
Total Chinook Salmon 3,025
Yentna River (RM 18)
Chinook Salmon (≥ 50 cm)a 1,375 50.0 110.0 66.8 1,367
Chinook Salmon (< 50 cm)a 930 24.0 49.5 37.0 924
Total Chinook Salmon 2,305
a Total catch by size category estimated from length samples.
Length (cm METF)
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Table A-5. Number of salmon captured at three fishwheel sites and in gillnets in the Middle River, by size category, 2014.
Species Large Small Total Large Small Total Large Small Total Large Small Total Large Small Total
Chinook Salmon 273 84 357 79 18 97 320 102 422 0 1 1 672 205 877
Chum Salmon 581 0 581 417 0 417 471 0 471 83 0 83 1,552 0 1,552
Coho Salmon 111 1 112 25 0 25 197 1 198 42 0 42 375 2 377
Pink Salmon 3,011 0 3,011 73 0 73 4,389 0 4,389 0 0 0 7,473 0 7,473
Sockeye Salmon 59 4 63 92 2 94 62 4 66 10 1 11 223 11 234
Total 4,035 89 4,124 686 20 706 5,439 107 5,546 135 2 137 10,295 218 10,513
Notes:
Totals include all tagged fish recaptured at the fishwheels (30 large Chinook, 2 small Chinook, 8 Chum, 5 Coho, 10 Pink, and 3 Sockeye salmon). Large Chinook Salmon measured 50 cm
METF or greater; and large Chum, Coho, Pink, and Sockeye salmon measured 40 cm METF or greater.
Gill Net
Fishwheels
All Gear CombinedSite 1 Site 2 Site 3
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Table A-6. Number of fish caught, tagged, and biosampled at the Middle River fishwheels, 2014.
Total Radio-
Species Name Catch a tagged Min Max Mean n
Chinook Salmon (≥ 50 cm)672 590 50 108 71.6 624 589
Chinook Salmon (< 50 cm)204 32 27 49 35.9 198 30
Chum Salmon 1,469 200 45 69 57.9 1,102 194
Coho Salmon 333 212 33 65 54.0 324 199
Pink Salmon 7,473 201 32 67 45.7 955 201
Sockeye Salmon 213 200 33 61 49.3 217 198
Arctic Grayling 17 -13 36 20.9 16 -
Burbot 2 -15 15 15.0 2 -
Dolly Varden 8 -20 43 32.4 5 6
Longnose Sucker 13 -14 38 29.8 13 -
Rainbow Trout 68 -16 53 27.3 63 -
Round Whitefish 67 -13 37 26.2 65 -
Humpback Whitefish 13 -18 41 31.0 11 9
b Total catch includes recaptures for all salmon, and small (MEF < 40 cm) Coho and Sockeye salmon.
a Salmon are measured from mid-eye to fork of tail (MEF); other species are fork lengths (FL).
d An additonal 18 Coho Salmon were captured using gillnets and radio-tagged; of which 15 were tissue-sampled.
MEF / Fork Length (cm) b Tissue
Samplesc
c No tissue samples were collected from Arctic Grayling, Burbot, Longnose Sucker, Rainbow Trout, or Round Whitefish
because the required sample sizes had been met prior to the 2014 field season.
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Table A-7. Daily fishing effort and the number of salmon caught and radio-tagged during gillnet operations
in the vicinity of Curry, 2014.
Date
Chinook
Salmon
(Small)
Sockeye
Salmon
Chum
Salmon
Coho
Salmon
24-Jun 1 1.8 1 0 0 0 0
10-Sep 2 16.4 0 2 16 14 3
12-Sep 2 16.0 0 1 5 5 3
14-Sep 1 8.0 0 0 7 7 3
16-Sep 1 8.0 0 3 1 2 1
18-Sep 2 16.0 0 2 17 9 5
20-Sep 2 16.0 0 2 19 4 2
22-Sep 2 16.0 0 0 9 0 0
24-Sep 2 16.0 0 1 3 0 0
26-Sep 2 16.0 0 0 3 0 0
28-Sep 2 16.0 0 0 3 0 0
30-Sep 1 6.0 0 0 0 1 1
Total 152.1 1 11 83 42 18
Notes:
Two of the coho salmon captured on September 20 were recaptures. One of the 11 sockeye salmon caught was a
jack (MEF < 40 cm). Fishing sites were located between PRM 121.9 and 126.0.
Coho
Salmon
Tagged
Total Effort
(net hours)
Number
of
Crews
Adult Salmon Catch
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Table A-8. Summary of run-timing and catch information for salmon captured in fishwheels located in the
Middle River near Curry, by year and species.
Species 1981 1982 1983 1984 1985 2012 2013 2014
Date First Fish Caught 6-15 6-15 6-10 6-9 6-20 6-18 6-16 6-11
Date Last Fish Caught 8-20 8-6 7-31 7-29 8-16 8-9 8-28 8-24
Midpoint of Catch Date (50%)6-24 7-3 6-25 6-25 7-9 7-3 6-30 7-2
Peak Daily Catch (Date)6-23 7-4 6-22 6-22 7-8 7-2 7-2 7-1
Peak Daily Catch (Fish)31 55 82 165 98 62 78 70
Total Catch (Fish)284 791 1,064 1,589 1,098 566 952 876
Date First Fish Caught 7-20 7-25 7-10 7-15 7-17 7-10 7-13 7-5
Date Last Fish Caught 9-15 9-14 9-9 9-7 9-12 9-1 9-9 9-5
Midpoint of Catch Date (50%)8-17 8-12 8-3 8-6 8-7 8-7 8-5 8-12
Peak Daily Catch (Date)8-6 8-13 8-2 8-5 8-6 8-2 8-3 8-11
Peak Daily Catch (Fish)87 168 78 366 166 181 259 89
Total Catch (Fish)1,276 1,736 861 4,228 1,305 1,734 3,417 1,469
Date First Fish Caught 8-4 8-2 7-22 7-18 8-3 7-28 7-23 7-22
Date Last Fish Caught 9-19 9-11 9-6 8-31 9-12 8-31 9-21 9-3
Midpoint of Catch Date (50%)8-23 8-18 8-12 8-12 8-18 8-15 8-15 8-20
Peak Daily Catch (Date)8-29 8-19 8-15 8-4 8-20 8/11,8/15 8-17 8-22
Peak Daily Catch (Fish)16 15 10 21 18 21 139 30
Total Catch (Fish)182 229 93 350 203 265 1,723 335
Date First Fish Caught 7-18 7-22 7-20 7-7 7-15 7-16 7-8 7-16
Date Last Fish Caught 8-29 8-26 8-23 8-29 8-28 8-31 9-4 8-30
Midpoint of Catch Date (50%)8-8 8-6 8-1 8-4 8-5 8-6 8-3 7-31
Peak Daily Catch (Date)8-6 8-5 8-1 8-5 8-6 8-2 8-3 7-29
Peak Daily Catch (Fish)39 1,199 67 2,052 147 548 1,422 979
Total Catch (Fish)234 7,302 589 17,394 1,172 4,705 15,695 7,473
Date First Fish Caught 7-17 7-16 7-6 6-26 7-16 7-2 6-15 6-29
Date Last Fish Caught 9-12 9-18 9-4 9-8 9-4 8-22 9-10 9-3
Midpoint of Catch Date (50%)8-5 8-5 8-5 8-1 8-7 7-30 8-5 8-1
Peak Daily Catch (Date)8-5 8-5 8/2,8/12,8/13 7-30 8-6 7-21 8-15 7-28
Peak Daily Catch (Fish)44 16 10 34 29 8 16 13
Total Catch (Fish)469 161 201 379 324 100 276 223
Sockeye Salmon
Year
Chinook Salmon
Chum Salmon
Coho Salmon
Pink Salmon
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FERC Project No. 14241 Appendix A – Page 8 October 2015
Table A-9. Comparisons between the cumulative length-frequency distributions of fish sampled in the Lower
River and Yentna River using the Kolmogorov-Smirnov (KS) two-sample test, 2014.
Sample 1 Sample 2 n1 n 2 Dmax P-value
Lower River
Chinook Salmon
East bank fishwheel West bank fishwheel 937 937 0.111 < 0.001
East bank fishwheel Gillnet 937 164 0.387 < 0.001
West bank fishwheel Gillnet 937 164 0.442 < 0.001
Total catch (METF ≥ 50 cm)Tagged (METF ≥ 50 cm)1,503 656 0.145 < 0.001
Total catch (METF ≥ 58 cm)Tagged (METF ≥ 58 cm)1,086 569 0.030 0.797
Coho Salmon
East bank fishwheel West bank fishwheel 551 810 0.083 0.011
Total catch (METF ≥ 40 cm)Tagged (METF ≥ 40 cm)1,349 640 0.023 0.886
Pink Salmon (METF ≥ 40 cm)
East bank fishwheel West bank fishwheel 90 107 0.145 0.140
Yentna River
Chinook Salmon @ RM6
South bank fishwheel North bank fishwheel 1,213 1,410 0.155 < 0.001
South bank fishwheel Gillnet 1,213 398 0.519 < 0.001
North bank fishwheel Gillnet 1,410 398 0.658 < 0.001
Total catch (METF ≥ 50 cm)Tagged (METF ≥ 50 cm)1,355 1,277 0.005 1.000
Chinook Salmon @ RM18
South bank fishwheel North bank fishwheel 739 1,435 0.250 < 0.001
South bank fishwheel Gillnet 739 118 0.528 < 0.001
North bank fishwheel Gillnet 1,435 118 0.671 < 0.001
Length-Frequency Distributions Sample Size
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FERC Project No. 14241 Appendix A – Page 9 October 2015
Table A-10. Comparisons between the cumulative length-frequency distributions of fish sampled in the
Middle River using the Kolmogorov-Smirnov (KS) two-sample test, 2014.
Sample 1 Sample 2 n 1 n 2 Dmax P-value
Chinook Salmon (Large)
Site 1 fishwheel catch Site 2 fishwheel catch 339 95 0.12 0.22
Site 1 fishwheel catch Site 3 fishwheel catch 339 388 0.04 1.00
Site 2 fishwheel catch Site 3 fishwheel catch 95 388 0.12 0.19
Total catch (METF ≥ 50 cm)Tagged (METF ≥ 50 cm)624 589 0.01 1.00
Chinook Salmon (Small)
Total catch (METF < 50 cm)Tagged (METF < 50 cm)198 32 0.77 < 0.01
Chum Salmon
Site 1 fishwheel catch Site 2 fishwheel catch 399 342 0.14 0.00
Site 1 fishwheel catch Site 3 fishwheel catch 399 361 0.04 0.93
Site 2 fishwheel catch Site 3 fishwheel catch 342 361 0.15 < 0.01
Total catch (METF ≥ 40 cm)Tagged (METF ≥ 40 cm)1,102 200 0.08 0.25
Coho Salmon
Site 1 fishwheel catch Site 2 fishwheel catch 108 25 0.24 0.20
Site 1 fishwheel catch Site 3 fishwheel catch 108 191 0.05 1.00
Site 2 fishwheel catch Site 3 fishwheel catch 25 191 0.24 0.15
Total catch (METF ≥ 40 cm)Tagged (METF ≥ 40 cm)324 212 0.04 1.00
Pink Salmon
Site 1 fishwheel catch Site 2 fishwheel catch 440 66 0.06 1.00
Site 1 fishwheel catch Site 3 fishwheel catch 440 449 0.09 0.04
Site 2 fishwheel catch Site 3 fishwheel catch 66 449 0.1 0.66
Total catch Tagged 955 201 0.15 < 0.01
Sockeye Salmon
Site 1 fishwheel catch Site 2 fishwheel catch 60 93 0.1 0.93
Site 1 fishwheel catch Site 3 fishwheel catch 60 64 0.08 1.00
Site 2 fishwheel catch Site 3 fishwheel catch 93 64 0.09 1.00
Total catch (METF ≥ 40 cm)Tagged (METF ≥ 40 cm)217 200 0.04 1.00
Length-Frequency Distributions Sample Size
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FERC Project No. 14241 Appendix A – Page 10 October 2015
Figure A-1. Daily fishing effort (hours) at two fishwheel sites in the Lower River, 2014.
Figure A-2. Daily gillnet effort (hours) in the Lower River, by mesh size, 2014. Fishing Effort (h) Date (m/d)
0
3
6
9
12
15
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25Effort
West Bank
0
3
6
9
12
15
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25East Bank
0
1
2
3
4
5
5/225/245/265/285/306/16/36/56/76/96/116/136/156/176/196/216/236/256/27Fishing Effort (h)Date (m/d)
7.5-in Mesh
5.5-in Mesh
Gillnet
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Figure A-3. Daily fishing effort (hours) at four fishwheel sites in the Yentna River, 2014. Fishing Effort (h) Date (m/d)
0
5
10
15
20
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25RM 6 -South Bank
0
5
10
15
20
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25RM 6 -North Bank
0
5
10
15
20
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25RM 18 -South Bank
0
5
10
15
20
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25RM 18 -North Bank
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Figure A-4. Daily gillnet effort (hours) during tagging (top panel) and recovery (bottom panel) operations in
the Yentna River, by mesh size, 2014.
Figure A-5. Daily fishing effort (hours) and rotational speed (RPM) at three fishwheel sites in the Middle
River, 2014. Fishing Effort (hours) Date (m/d)
0
5
10
15
20
5/225/245/265/285/306/16/36/56/76/96/116/136/156/176/196/216/236/256/276/297.5-in Mesh
5.5-in Mesh
Yentna River (RM 6)
0
5
10
15
20
5/225/245/265/285/306/16/36/56/76/96/116/136/156/176/196/216/236/256/276/29Yentna River (RM 18 )
Date (m/d)Fishing Effort (h)Rotational Speed (RPM)0
2
4
6
8
0
4
8
12
16
20
24
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/4Effort RPM
Site 1 (west bank)
0
2
4
6
8
0
4
8
12
16
20
24
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/4Site 2 (east bank)
0
2
4
6
8
0
4
8
12
16
20
24
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/4Site 3 (west bank)
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Figure A-6. Daily number of radio tags applied to adult salmon species captured at two fishwheel sites and in
gillnets in the Lower River, 2014.
Date (m/d)Radio Tags Applied0
10
20
30
40
5/225/296/56/126/196/267/37/107/177/247/318/78/148/21Gillnet
East Bank
West Bank
Chinook
Salmon
0
5
10
15
20
5/225/296/56/126/196/267/37/107/177/247/318/78/148/21Pink
Salmon
0
20
40
60
80
5/225/296/56/126/196/267/37/107/177/247/318/78/148/21Coho
Salmon
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Figure A-7. Daily number of radio tags applied to adult salmon species captured at two fishwheel sites and in
gillnets in the Yentna River (RM 6), 2014. Radio Tags Applied Date (m/d)
0
5
10
15
20
25
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/15Gillnet
North Bank
South Bank
Chinook
Salmon
0
1
2
3
4
5
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/15Coho
Salmon
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FERC Project No. 14241 Appendix A – Page 15 October 2015
Figure A-8. Daily number of radio tags applied to adult salmon species captured at three fishwheel sites and
in gillnets in the Middle River, 2014.
Date (m/d)Radio Tags Applied0
15
30
45
60
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Gillnet
Site 3 (west bank)
Site 2 (east bank)
Site 1 (west bank)
Large Chinook Salmon (≥ 50 cm METF)
0
1
2
3
4
5
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Small Chinook Salmon (< 50 cm METF)
0
5
10
15
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Sockeye
Salmon
0
5
10
15
20
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Pink
Salmon
0
5
10
15
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Chum
Salmon
0
5
10
15
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Coho
Salmon
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Figure A-9. Daily catch-per-unit-effort of adult salmon species at the Lower River fishwheels, and the
Susitna River discharge at Sunshine, 2014. Catch-per-unit-effort (fish per hour)Discharge (cfs)Date (m/d)
0
20,000
40,000
60,000
80,000
100,000
0
1
2
3
4
5
6
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/20Chinook Salmon
0
20,000
40,000
60,000
80,000
100,000
0
20
40
60
80
100
120
140
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/20Discharge
East
West
Pink Salmon
0
20,000
40,000
60,000
80,000
100,000
0
20
40
60
80
100
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/20Coho Salmon
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Figure A-10. Daily catch-per-unit-effort for Chinook and Coho salmon at the Yentna River fishwheels, by
site, 2014.
Date (m/d)Catch-per-unit-effort (fish per hour)0
2
4
6
8
10
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25North Fishwheel
South Fishwheel
RM 6 -Chinook Salmon
0
3
6
9
12
15
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25RM 6 -Coho Salmon
0
2
4
6
8
10
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25RM 18 -Chinook Salmon
0
5
10
15
20
25
30
35
5/225/276/16/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/25RM 18 -Coho Salmon
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Figure A-11. Number of radio tags deployed in species of salmon at the Middle River fishwheels in 2014
relative to fishwheel catches in 2012, 2013, and 2014.
Date (m/d)Fishwheel CatchTags Deployed0
5
10
15
20
0
250
500
750
1,000
1,250
1,500
6-66-136-206-277-47-117-187-258-18-88-158-228-299-52012 catch (4705)
2013 catch (15695)
2014 catch (7472)
2014 tags (200)
Pink Salmon
0
2
4
6
8
10
12
14
0
50
100
150
200
250
300
6-66-136-206-277-47-117-187-258-18-88-158-228-299-52012 catch (1734)
2013 catch (3417)
2014 catch (1469)
2014 tags (200)
Chum Salmon
0
3
6
9
12
15
0
50
100
150
6-66-136-206-277-47-117-187-258-18-88-158-228-299-52012 catch (264)
2013 catch (1711)
2014 catch (334)
2014 tags (212)
Coho Salmon
0
10
20
30
40
50
60
0
10
20
30
40
50
60
70
6-66-136-206-277-47-117-187-258-18-88-158-228-299-52012 catch (422)
2013 catch (616)
2014 catch (672)
2014 tags (590)
Chinook
Salmon
0
2
4
6
8
10
12
14
0
2
4
6
8
10
12
14
6-66-136-206-277-47-117-187-258-18-88-158-228-299-52012 catch (92)
2013 catch (176)
2014 catch (213)
2014 tags (200)
Sockeye Salmon
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Figure A-12. Daily catch-per-unit-effort at the Middle River fishwheels, by species, and the Susitna River
discharge at Gold Creek, 2014.
Date (m/d)Catch-per-unit-effort (fish per hour)Discharge (cfs)0
10,000
20,000
30,000
40,000
50,000
0.0
0.5
1.0
1.5
2.0
6/96/146/196/246/297/47/97/147/197/247/298/38/88/138/188/238/289/29/7Discharge
Site 1
Site 2
Site 3
Large
Chinook Salmon
0
10,000
20,000
30,000
40,000
50,000
0.0
0.2
0.4
0.6
0.8
6/96/146/196/246/297/47/97/147/197/247/298/38/88/138/188/238/289/29/7Sockeye Salmon
0
10,000
20,000
30,000
40,000
50,000
0
10
20
30
40
50
60
6/96/146/196/246/297/47/97/147/197/247/298/38/88/138/188/238/289/29/7Pink Salmon
0
10,000
20,000
30,000
40,000
50,000
0
1
2
3
4
6/96/146/196/246/297/47/97/147/197/247/298/38/88/138/188/238/289/29/7Chum Salmon
0
10,000
20,000
30,000
40,000
50,000
0.0
0.5
1.0
1.5
2.0
6/96/146/196/246/297/47/97/147/197/247/298/38/88/138/188/238/289/29/7Coho Salmon
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Figure A-13. Comparison of Chinook Salmon catches (top panel), relative proportion of catches (middle
panel), and cumulative proportion of catches (bottom panel), at the Middle River fishwheels near Curry, by
year. These data include Chinook Salmon of all size categories and catches at two (1981-2012) or three (2013
and 2014) fishwheels.
Date (m/d)
0.0
0.2
0.4
0.6
0.8
1.0
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Cumulative Proportion of Catch0
30
60
90
120
150
180
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Catch (# fish)1981
1982
1983
1984
1985
2012
2013
2014
Chinook
Salmon
0.00
0.02
0.04
0.06
0.08
0.10
0.12
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Relative Proportion of Catch
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Figure A-14. Comparison of Chum Salmon catches (top panel), relative proportion of catches (middle panel),
and cumulative proportion of catches (bottom panel), at the Middle River fishwheels near Curry, by year.
These data include adult Chum Salmon of all size categories and catches at two (1981-2012) or three (2013
and 2014) fishwheels.
Date (m/d)
0.0
0.2
0.4
0.6
0.8
1.0
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Cumulative Proportion of Catch0
50
100
150
200
250
300
350
400
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Catch (# fish)1981
1982
1983
1984
1985
2012
2013
2014
Chum
Salmon
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Relative Proportion of Catch
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Figure A-15. Comparison of Coho Salmon catches (top panel), relative proportion of catches (middle panel),
and cumulative proportion of catches (bottom panel), at the Middle River fishwheels near Curry, by year.
These data include adult Coho Salmon of all size categories and catches at two (1981-2012) or three (2013 and
2014) fishwheels.
Date (m/d)
0.0
0.2
0.4
0.6
0.8
1.0
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Cumulative Proportion of Catch0
20
40
60
80
100
120
140
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Catch (# fish)1981
1982
1983
1984
1985
2012
2013
2014
Coho
Salmon
0.00
0.02
0.04
0.06
0.08
0.10
0.12
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Relative Proportion of Catch
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Figure A-16. Comparison of Pink Salmon catches (top panel), relative proportion of catches (middle panel),
and cumulative proportion of catches (bottom panel), at the Middle River fishwheels near Curry, by year.
These data include adult Pink Salmon of all size categories and catches at two (1981-2012) or three (2013 and
2014) fishwheels.
Date (m/d)
0.0
0.2
0.4
0.6
0.8
1.0
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Cumulative Proportion of Catch0
500
1,000
1,500
2,000
2,500
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Catch (# fish)1981
1982
1983
1984
1985
2012
2013
2014
Pink
Salmon
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Relative Proportion of Catch
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Figure A-17. Comparison of Sockeye Salmon catches (top panel), relative proportion of catches (middle
panel), and cumulative proportion of catches (bottom panel), at the Middle River fishwheels near Curry, by
year. These data include adult Sockeye Salmon of all size categories and catches at two (1981-2012) or three
(2013 and 2014) fishwheels.
Date (m/d)
0.0
0.2
0.4
0.6
0.8
1.0
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Cumulative Proportion of Catch0
10
20
30
40
50
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Catch (# fish)1981
1982
1983
1984
1985
2012
2013
2014
Sockeye
Salmon
0.00
0.02
0.04
0.06
0.08
0.10
6/66/116/166/216/267/17/67/117/167/217/267/318/58/108/158/208/258/309/49/99/149/199/249/29Relative Proportion of Catch
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 25 October 2015
Figure A-18. Daily sampling effort, and the amount of imagery reviewed (review effort), for an ARIS sonar
unit operated immediately downstream of the fishwheel at Site 1 in the Middle River, 2014.
Figure A-19. Catch-per-unit-effort, or the number of targets counted per hour of imagery reviewed, on the
ARIS unit located immediately downstream of the Site 1 fishwheel, 2014. ARIS data were included,
regardless of whether the Site 1 fishwheel was operational. Imagery collected after June 17 was subsampled
and the counts were expanded to full hourly counts. From June 3 to June 25, targets measuring 50 cm or
greater were included; whereas from August 29 to September 30, targets measuring 40 cm or greater were
included. Data on two days when CPUE was less than zero were excluded (-0.8 fish/hour on September 25
and -1.1 fish/hour on September 27). Turbidity measurements recorded at Site 1 and an overlay of Susitna
River discharge at the Gold Creek gauge are also shown.
0
4
8
12
16
20
24
6/36/86/136/186/236/287/37/87/137/187/237/288/28/78/128/178/228/279/19/69/119/169/219/26Effort (h)Date (m/d)
Sampling Effort (h)
Review Effort (h)
Discharge at Gold Cr
0
50
100
150
200
250
300
350
0
5
10
15
20
25
30
35
40
45
6/36/86/136/186/236/287/37/87/137/187/237/288/28/78/128/178/228/279/19/69/119/169/219/26Turbidity (NTU)ARIS CPUE (fish/hour)Date (m/d)
CPUE
Turbidity
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 26 October 2015
Figure A-20. Comparison of the catch-per-unit-effort of adult salmon at the Site 1 fishwheel and concurrent
net upstream counts of fish on the ARIS unit located immediately downstream of the fishwheel, 2014.
Imagery collected after June 17 was subsampled and the counts were expanded to full hourly counts. From
June 3 to June 25, targets measuring 50 cm or greater were included; whereas from August 29 to September
30, targets measuring 40 cm or greater were included. An overlay of Susitna River discharge at the Gold
Creek gauge is also shown.
Figure A-21. Relative percentage of fish counted using ARIS at Site 1 as a function of the distance where they
were first detected in the field of view, by time period, 2014. From June 3 to June 25, targets measuring 50
cm or greater were included; whereas from August 29 to September 30, targets measuring 40 cm or greater
were included. Discharges (cfs) refer to the Susitna River at the Gold Creek gauge.
Discharge at Gold Cr
0.0
0.2
0.4
0.6
0.8
1.0
1.2
0
50
100
150
200
250
6/36/86/136/186/236/287/37/87/137/187/237/288/28/78/128/178/228/279/19/69/119/169/219/26Fishwheel CPUE (fish/hour)Net Upstream ARIS CountDate (m/d)
ARIS Count
Fishwheel CPUE
0
3
6
9
12
15
18
21
24
27
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16Percent of ARIS CountsDistance from ARIS Unit (m)
June 3-15, n = 255 (13,300-19,800 cfs)
June 16-25, n = 770 (21,800-25,700 cfs)
Aug 29-Sep 30, n = 1305 (6,190-22,500 cfs)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 27 October 2015
Figure A-22. Diel migration of upstream-moving fish counted using ARIS at Site 1, by size category and time
period, 2014. Top panel: 24 hours of imagery collected, all imagery reviewed. Middle panel: 24 hours of
imagery collected, 8 hours of imagery reviewed each day. Chinook Salmon were the main species being
captured at the Site 1 fishwheel through late June. Bottom panel: 24 hours of imagery collected, 8 hours of
imagery reviewed each day. Chum and Coho salmon were presumably the predominant species migrating
through the Middle River in September. ARIS CountsTime of Day (hour)
0
10
20
30
40
01234567891011121314151617181920212223METF ≥ 50 cm (n = 522)
METF 40-49 cm (n = 29)
June 4-9 and June 12-17
0
5
10
15
20
25
30
01234567891011121314151617181920212223METF ≥ 50 cm (n = 342)
METF = 40-49 cm (n = 37)
June 19-24
0
10
20
30
40
50
60
01234567891011121314151617181920212223METF ≥ 50 cm (n = 864)
METF = 40-49 cm (n = 119)
September 1 -20 and September 22 -29
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 28 October 2015
Figure A-23. Cumulative length-frequency distributions for Chinook Salmon captured in the Lower River,
by capture site, 2014.
Figure A-24. Cumulative length-frequency distributions for Chinook and Pink salmon caught and radio-
tagged in the Lower River, by species, 2014.
Mid-eye to Fork Length (cm)Cumulative Proportion0.0
0.2
0.4
0.6
0.8
1.0
20 30 40 50 60 70 80 90 100 110
Chinook Salmon
West Bank
East Bank
Gillnet
Mid-eye to Fork Length (cm)Cumulative Proportion0.0
0.2
0.4
0.6
0.8
1.0
30 40 50 60 70 80 90 100 110 120 130
Chinook Salmon
Caught
Radio-tagged
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60
Pink Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 29 October 2015
Figure A-25. Cumulative length-frequency distributions for Chinook Salmon radio-tagged in the Lower
River and inspected and recaptured at the Deshka River and Montana Creek weir sites, 2014.
Figure A-26. Cumulative length-frequency distributions for Chinook Salmon captured at RM 6 (left panel)
and RM 18 (right panel) in the Yentna River, 2014.
Cumulative Proportion Mid-eye to Fork Length (cm)
0.0
0.2
0.4
0.6
0.8
1.0
30 40 50 60 70 80 90 100 110 120
Montana Weir
Chinook Salmon
Tagged in
Lower River
Inspected at
Weir
Recaptures
at Weir
0.0
0.2
0.4
0.6
0.8
1.0
30 40 50 60 70 80 90 100 110 120
Deshka Weir
Chinook Salmon
Cumulative ProportionMid-eye to Fork Length (cm)
0.0
0.2
0.4
0.6
0.8
1.0
20 30 40 50 60 70 80 90 100 110 120
RM 6
South Bank
North Bank
Gillnet
0.0
0.2
0.4
0.6
0.8
1.0
20 30 40 50 60 70 80 90 100 110 120
RM 18
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 30 October 2015
Figure A-27. Cumulative length-frequency distributions for Chinook Salmon measuring 50 cm METF or
greater that were caught and dart-tagged in the Yentna River (RM 6), 2014.
Figure A-28. Cumulative length-frequency distributions for Chinook Salmon dart-tagged at Yentna RM 6
and inspected and recaptured at Yentna RM 18 (fishwheels and gillnets combined), 2014.
0.0
0.2
0.4
0.6
0.8
1.0
50 60 70 80 90 100 110Cumulative ProportionMid-eye to Fork Length (cm)
Caught
Dart-tagged
Mid-eye to Fork Length (cm)Cumulative Proportion0.0
0.2
0.4
0.6
0.8
1.0
20 30 40 50 60 70 80 90 100 110 120
Chinook Salmon
Tagged at Yentna RM 6
Inspected for Tags
Recaptures
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 31 October 2015
Figure A-29. Cumulative length-frequency distributions for salmon captured in the Middle River fishwheels,
by species and capture site, 2014.
Mid-eye to Fork Length (cm)Cumulative Proportion0.0
0.2
0.4
0.6
0.8
1.0
25 35 45 55 65 75 85 95 105 115
Chinook Salmon
(Large)
Site 1
Site 2
Site 3
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70
Sockeye Salmon
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70
Pink Salmon
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70
Coho Salmon
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70
Chum Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix A – Page 32 October 2015
Figure A-30. Cumulative length-frequency distributions for salmon caught and radio-tagged in the Middle
River, by species, 2014.
Mid-eye to Fork Length (cm)Cumulative Proportion0.0
0.2
0.4
0.6
0.8
1.0
45 55 65 75 85 95 105 115
Chinook Salmon
(≥ 50 cm METF)
Captured in the
Middle River
Radio-tagged
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70 75
Sockeye Salmon
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60
Pink Salmon
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70 75 80
Chum Salmon
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70
Coho Salmon
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50
Chinook Salmon
(< 50 cm METF)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 October 2015
Appendix B: Daily fish passage at weir and sonar sites in the Lower and
Middle rivers
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 1 October 2015
Table B-1. Deshka River weir daily passage rates and tag recaptures, by species, 2014.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Count Count
19-May 2 2 0 0 0 0 0 0 0
20-May 3 5 0 0 0 0 0 0 0 0
21-May 4 9 0 0 0 0 0 0 0 0
22-May 10 19 0 0 0 0 0 0 0 0
23-May 8 27 1 0 0 0 0 0 0 0
24-May 9 36 1 0 0 0 0 0 0 0
25-May 15 51 0 0 0 0 0 0 0 0
26-May 25 76 0 0 0 0 0 0 0 0
27-May 6 82 2 0 0 0 0 0 0 0
28-May 7 89 0 0 0 0 0 0 0 0
29-May 93 182 1 0 0 0 0 0 0 0 0
30-May 14 196 4 0 0 0 0 0 0 0 0
31-May 39 235 3 0 0 0 0 0 0 0 0
01-Jun 13 248 4 0 0 0 0 0 0 0 0
02-Jun 166 414 6 0 0 0 0 0 0 0 0
03-Jun 214 628 9 0 0 0 0 0 0 0 0
04-Jun 86 714 8 0 0 0 0 0 0 0 0
05-Jun 454 1,168 8 0 0 0 0 0 0 0 0
06-Jun 735 1,903 10 0 0 0 0 0 0 0 0
07-Jun 715 2,618 5 0 0 0 0 0 0 0 0
08-Jun 608 3,226 6 0 0 0 0 0 0 0 0
09-Jun 1,065 4,291 5 0 0 0 0 0 0 0 0
10-Jun 2,279 6,570 8 0 0 0 0 0 0 0 0
11-Jun 1,463 8,033 7 0 0 0 0 0 0 0 0
12-Jun 1,033 9,066 5 0 0 0 0 0 0 0 0
13-Jun 994 10,060 8 0 0 0 0 0 0 0 0
14-Jun 666 10,726 1 0 0 0 0 0 0 0 0
15-Jun 758 11,484 0 0 0 0 0 0 0 0 0
16-Jun 955 12,439 4 0 0 0 0 0 0 0 0
17-Jun 712 13,151 3 0 0 0 0 0 0 0 0
18-Jun 455 13,606 5 0 0 0 0 0 0 0 0
Chinook Salmon Coho Salmon Chum Salmon Sockeye SalmonPink Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 2 October 2015
Table B-1. Continued.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Count Count
19-Jun 320 13,926 1 0 0 0 0 0 0 0 0
20-Jun 432 14,358 1 0 0 0 0 0 0 0 0
21-Jun 278 14,636 5 0 0 0 0 0 0 0 0
22-Jun 206 14,842 1 0 0 0 0 0 0 0 0
23-Jun 556 15,398 0 0 0 0 0 0 0 0 0
24-Jun 92 15,490 2 0 0 0 0 0 0 0 0
25-Jun 163 15,653 0 0 0 0 0 0 0 0 0
26-Jun 94 15,747 0 0 0 0 0 0 0 0 0
27-Jun 14 15,761 0 0 0 0 0 0 0 0 0
28-Jun 0 15,761 0 0 0 0 0 0 0 0 0
29-Jun 0 15,761 1 0 0 0 0 0 0 0 0
30-Jun 10 15,771 0 0 0 0 0 0 0 0 0
01-Jul 36 15,807 0 0 0 0 0 0 0 0 0
02-Jul 37 15,844 0 0 0 0 0 0 0 0 0
03-Jul 101 15,945 0 0 0 0 0 0 0 0 0
04-Jul 11 15,956 0 5 5 1 1 0 0 0 0
05-Jul 43 15,999 0 2 7 0 1 0 0 0 0
06-Jul 18 16,017 0 0 7 9 10 0 0 0 0
07-Jul 15 16,032 0 2 9 21 31 0 0 0 0
08-Jul 11 16,043 0 4 13 12 43 0 0 0 0
09-Jul 10 16,053 0 0 13 6 49 0 0 0 0
10-Jul 33 16,086 0 3 16 26 75 2 2 0 0
11-Jul 28 16,114 0 11 27 68 143 0 2 0 0
12-Jul 19 16,133 0 16 43 207 350 1 3 1 1
13-Jul 29 16,162 0 18 61 156 506 0 3 0 1
14-Jul 4 16,166 0 9 70 172 678 1 4 0 1
15-Jul 11 16,177 0 23 93 564 1,242 2 6 0 1
16-Jul 11 16,188 0 36 129 3,012 4,254 7 13 6 7
17-Jul 13 16,201 0 11 140 3,100 7,354 13 26 0 7
18-Jul 10 16,211 0 34 174 6,466 13,820 5 31 0 7
19-Jul 4 16,215 0 85 259 10,630 24,450 4 35 0 7
Chinook Salmon Coho Salmon Chum Salmon Sockeye SalmonPink Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 3 October 2015
Table B-1. Continued.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Count Count
20-Jul 2 16,217 0 88 347 4,350 28,800 1 36 0 7
21-Jul 12 16,229 0 132 479 11,144 39,944 5 41 4 11
22-Jul 3 16,232 0 82 561 3,351 43,295 2 43 0 11
23-Jul 7 16,239 0 155 716 10,275 53,570 2 45 0 11
24-Jul 0 16,239 0 139 855 7,837 61,407 4 49 2 13
25-Jul 2 16,241 0 136 991 3,686 65,093 2 51 3 16
26-Jul 3 16,244 0 487 1,478 3,367 68,460 3 54 1 17
27-Jul 3 16,247 0 296 1,774 2,976 71,436 2 56 1 18
28-Jul 1 16,248 0 79 1,853 1,610 73,046 1 57 0 18
29-Jul 0 16,248 0 58 1,911 731 73,777 1 58 1 19
30-Jul 2 16,250 0 412 2,323 1,650 75,427 3 61 0 19
31-Jul 2 16,252 0 123 2,446 642 76,069 4 65 0 19
01-Aug 0 16,252 0 19 2,465 107 76,176 1 66 0 19
02-Aug 0 16,252 0 80 2,545 482 76,658 1 67 0 19
03-Aug 2 16,254 0 65 2,610 240 76,898 0 67 0 19
04-Aug 5 16,259 0 12 2,622 144 77,042 9 76 0 19
05-Aug 2 16,261 0 152 2,774 194 77,236 5 81 2 21
06-Aug 1 16,262 0 308 3,082 192 77,428 0 81 0 21
07-Aug 2 16,264 0 262 3,344 152 77,580 1 82 1 22
08-Aug 1 16,265 0 364 3,708 134 77,714 3 85 0 22
09-Aug 3 16,268 0 385 4,093 79 77,793 1 86 0 22
10-Aug 0 16,268 0 376 4,469 73 77,866 0 86 0 22
11-Aug 2 16,270 0 418 4,887 31 77,897 2 88 2 24
12-Aug 3 16,273 0 177 5,064 15 77,912 0 88 1 25
13-Aug 3 16,276 0 210 5,274 14 77,926 0 88 0 25
14-Aug 6 16,282 0 179 5,453 41 77,967 2 90 0 25
15-Aug 5 16,287 0 265 5,718 19 77,986 3 93 0 25
16-Aug 5 16,292 0 380 6,098 17 78,003 2 95 0 25
17-Aug 7 16,299 0 2,810 8,908 34 78,037 5 100 0 25
18-Aug 7 16,306 0 153 9,061 11 78,048 4 104 0 25
19-Aug 8 16,314 0 184 9,245 19 78,067 2 106 0 25
Chinook Salmon Coho Salmon Chum Salmon Sockeye SalmonPink Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 4 October 2015
Table B-1. Continued.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Count Count
20-Aug 1 16,315 0 128 9,373 12 78,079 0 106 0 25
21-Aug 5 16,320 0 103 9,476 3 78,082 1 107 0 25
22-Aug 1 16,321 0 130 9,606 2 78,084 0 107 0 25
23-Aug 0 16,321 0 137 9,743 3 78,087 0 107 0 25
24-Aug 0 16,321 0 102 9,845 1 78,088 1 108 0 25
25-Aug 2 16,323 0 142 9,987 2 78,090 1 109 1 26
26-Aug 0 16,323 0 159 10,146 1 78,091 0 109 0 26
27-Aug 2 16,325 0 284 10,430 3 78,094 1 110 0 26
28-Aug 5 16,330 0 418 10,848 8 78,102 0 110 0 26
29-Aug 0 16,330 0 649 11,497 9 78,111 0 110 0 26
30-Aug 0 16,330 0 0 11,497 0 78,111 0 110 0 26
31-Aug 2 16,332 0 28 11,525 0 78,111 0 110 0 26
01-Sep 3 16,335 0 31 11,556 0 78,111 0 110 0 26
02-Sep 0 16,335 0 22 11,578 0 78,111 0 110 0 26
Total 16,335 125 11,578 78,111 110 26
Chinook Salmon Coho Salmon Chum Salmon Sockeye SalmonPink Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 5 October 2015
Table B-2. Montana Creek weir daily passage rates and tag recaptures, by species, 2014.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Comment
29-May 1
30-May 0
31-May 0
01-Jun 1
02-Jun 0
03-Jun 0
04-Jun 0 0 0 0 0 0 0 0 0 Weir installed 6/4
05-Jun 0 0 1 0 0 0 0 0 0
06-Jun 0 0 0 0 0 0 0 0 0
07-Jun 0 0 1 0 0 0 0 0 0
08-Jun 0 0 1 0 0 0 0 0 0
09-Jun 0 0 2 0 0 0 0 0 0
10-Jun 0 0 2 0 0 0 0 0 0
11-Jun 0 0 0 0 0 0 0 0 0
12-Jun 0 0 1 0 0 0 0 0 0
13-Jun 0 0 0 0 0 0 0 0 0
14-Jun 0 0 0 0 0 0 0 0 0
15-Jun 0 0 2 0 0 0 0 0 0
16-Jun 0 0 0 0 0 0 0 0 0
17-Jun 0 0 2 0 0 0 0 0 0
18-Jun 0 0 0 0 0 0 0 0 0
19-Jun 0 0 0 0 0 0 0 0 0
20-Jun 0 0 0 0 0 0 0 0 0
21-Jun 0 0 0 0 0 0 0 0 0
22-Jun 0 1 0 0 0 0 0 0 0
23-Jun 1 1 0 0 0 0 0 0 0
24-Jun 0 4 0 0 0 0 0 0 0
25-Jun 3 4 0 0 0 0 0 0 0
26-Jun 0 4 1 0 0 0 0 0 0 Weir topped
27-Jun 0 4 0 0 0 0 0 0 0 Weir topped
28-Jun 0 4 0 0 0 0 0 0 0 Weir topped
Chinook Salmon Coho Salmon Pink Salmon Chum Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 6 October 2015
Table B-2. Continued.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Comment
29-Jun 0 4 0 0 0 0 0 0 0 Weir topped
30-Jun 0 4 0 0 0 0 0 0 0 Weir topped
01-Jul 0 11 0 0 0 0 0 0 0
02-Jul 7 25 0 0 0 0 0 0 0
03-Jul 14 57 0 0 0 0 0 0 0
04-Jul 32 85 0 0 0 0 0 0 0
05-Jul 28 119 0 0 0 0 0 0 0
06-Jul 34 253 0 0 0 0 0 0 0
07-Jul 134 320 0 0 0 0 0 1 1
08-Jul 67 324 0 0 0 0 0 0 1
09-Jul 4 403 0 0 0 0 0 0 1
10-Jul 79 455 0 0 0 0 0 2 3
11-Jul 52 477 0 0 0 0 0 10 13
12-Jul 22 493 0 0 0 0 0 1 14
13-Jul 16 545 0 0 0 0 0 2 16
14-Jul 52 594 0 0 0 0 0 9 25
15-Jul 49 2 0 0 0 0 0 3 28
16-Jul 12 615 0 0 0 0 0 4 32
17-Jul 9 645 0 0 0 0 0 12 44
18-Jul 30 647 0 0 0 0 0 9 53
19-Jul 2 768 0 0 0 0 0 8 61
20-Jul 121 797 0 0 0 0 0 28 89
21-Jul 29 823 0 0 0 1 1 6 95
22-Jul 26 900 0 0 0 0 1 16 111
23-Jul 77 905 0 0 0 2 3 45 156
24-Jul 5 997 0 0 0 8 11 43 199
25-Jul 92 1,031 0 0 0 118 129 161 360
26-Jul 34 1,033 0 0 0 34 163 74 434
27-Jul 2 1,040 0 0 0 17 180 15 449
28-Jul 7 1,071 0 0 0 23 203 59 508
29-Jul 31 1,120 0 0 0 36 239 121 629
Chinook Salmon Coho Salmon Pink Salmon Chum Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 7 October 2015
Table B-2. Continued.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Comment
30-Jul 49 1,129 0 0 0 28 267 71 700
31-Jul 9 1,134 0 0 0 34 301 89 789
01-Aug 5 1,139 0 0 0 64 365 159 948
02-Aug 5 1,146 0 0 0 69 434 189 1,137
03-Aug 7 1,159 0 2 2 46 480 202 1,339
04-Aug 13 1,172 0 0 2 68 548 372 1,711
05-Aug 13 1,177 0 0 2 91 639 357 2,068
06-Aug 5 1,188 0 1 3 70 709 152 2,220
07-Aug 11 1,192 0 3 6 59 768 239 2,459
08-Aug 4 1,193 0 0 6 49 817 97 2,556
09-Aug 1 1,193 0 1 7 67 884 171 2,727
10-Aug 0 1,196 0 2 9 37 921 127 2,854
11-Aug 3 1,199 0 3 12 42 963 179 3,033
12-Aug 3 1,200 0 7 19 49 1,012 140 3,173
13-Aug 1 1,201 0 3 22 35 1,047 227 3,400
14-Aug 1 1,203 0 7 29 29 1,076 196 3,596
15-Aug 2 1,204 0 21 50 57 1,133 524 4,120
16-Aug 1 1,205 0 5 55 12 1,145 90 4,210
17-Aug 1 1,207 0 6 61 17 1,162 60 4,270
18-Aug 2 1,208 0 2 63 21 1,183 66 4,336
19-Aug 1 1,208 0 6 69 12 1,195 114 4,450
20-Aug 0 1,208 0 3 72 8 1,203 90 4,540
21-Aug 0 1,208 0 6 78 4 1,207 111 4,651
22-Aug 0 1,208 0 4 82 10 1,217 134 4,785
23-Aug 0 1,208 0 1 83 3 1,220 149 4,934
24-Aug 0 1,211 0 3 86 3 1,223 135 5,069
25-Aug 3 1,213 0 32 118 9 1,232 249 5,318
26-Aug 2 1,215 0 5 123 4 1,236 92 5,410
27-Aug 2 1,215 0 52 175 6 1,242 134 5,544 Weir partially topped
28-Aug 0 1,215 0 87 262 2 1,244 112 5,656 Weir topped
29-Aug 0 1,215 0 1 263 0 1,244 3 5,659 Weir partially topped
Chinook Salmon Coho Salmon Pink Salmon Chum Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 8 October 2015
Table B-2. Continued.
Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Count Count Count Count Comment
30-Aug 0 1,215 0 3 266 1 1,245 11 5,670 Weir topped
31-Aug 0 1,215 0 4 270 0 1,245 40 5,710 Weir topped until 15:30
01-Sep 0 1,215 0 2 272 8 1,253 50 5,760
02-Sep 0 1,215 0 26 298 3 1,256 97 5,857
03-Sep 0 1,215 0 62 360 6 1,262 71 5,928
04-Sep 0 1,215 0 9 369 0 1,262 38 5,966
05-Sep 0 1,215 0 46 415 3 1,265 69 6,035
06-Sep 0 1,215 0 59 474 1 1,266 110 6,145
07-Sep 0 1,215 0 12 486 0 1,266 46 6,191
08-Sep 0 1,215 0 8 494 2 1,268 45 6,236
09-Sep 0 1,215 0 16 510 0 1,268 60 6,296
10-Sep 0 1,217 0 113 623 1 1,269 40 6,336
11-Sep 2 1,217 0 82 705 1 1,270 48 6,384
12-Sep 0 1,217 0 12 717 0 1,270 18 6,402
13-Sep 0 1,217 0 41 758 0 1,270 17 6,419
14-Sep 0 1,217 0 45 803 0 1,270 25 6,444
15-Sep 0 1,217 0 31 834 0 1,270 17 6,461
16-Sep 0 1,217 0 23 857 0 1,270 15 6,476
17-Sep 0 1,217 0 16 873 0 1,270 15 6,491
18-Sep 0 1,217 0 32 905 0 1,270 12 6,503
19-Sep 0 1,217 0 25 930 0 1,270 5 6,508 Weir partially topped
20-Sep 0 1,217 0 0 930 0 1,270 0 6,508
21-Sep 0 1,217 0 4 934 0 1,270 3 6,511
Total 1,217 15 934 1,270 6,511
Chinook Salmon Coho Salmon Pink Salmon Chum Salmon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 9 October 2015
Table B-3. Length statistics for tagged and untagged adult salmon sampled at the Deshka River and
Montana Creek weirs, by species, 2014.
Table B-4. Daily amount of video imagery collected and reviewed at the Indian River weir, and the net
upstream count of fish, by species, 2014.
Species Tagged
Not
Tagged Total Tagged
Not
Tagged Total
Chinook Salmon (≥ 50 cm METF)
Min 50.0 50.0 50.0 50.0 51.0 50.0
Max 98.0 94.5 98.0 88.5 107.0 107.0
Mean 66.1 68.8 67.9 66.4 69.1 68.7
n 125 251 376 15 226 241
Chinook Salmon (< 50 cm METF)
Min -34.5 34.5 -48.0 48.0
Max -49.5 49.5 -48.0 48.0
Mean -46.8 46.8 ---
n -45 45 -1 1
Coho Salmon (≥ 40 cm METF)
Min 40.0 44.0 40.0 52.0 40.0 40.0
Max 61.0 64.5 64.5 58.5 64.0 64.0
Mean 54.4 56.2 55.8 55.1 56.6 56.6
n 68 304 372 4 213 217
Deshka River Weir Montana Creek Weir
Date
Sample
Effort (h)
Review
Effort (h)
Rainbow
Trout
Round
Whitefish
22-Jun 10.5 10.5 0 0
23-Jun 24.0 24.0 0 1
24-Jun 24.0 24.0 1 0
25-Jun 24.0 24.0 2 1
26-Jun 6.5 1.3 0 0
Total 89.0 83.8 3 2
Net Upstream Count
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Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 10 October 2015
Table B-5. Daily number of Chinook Salmon inspected for tags, and the number of dart-tag recaptures, at
RM 18 sites on the Yentna River, 2014.
Daily Cum.Dart Cum.
Date Count Count Tags Tags
24-May 3 3 0 0
25-May 9 12 0 0
26-May 16 28 0 0
27-May 38 66 3 3
28-May 17 83 1 4
29-May 10 93 0 4
30-May 16 109 0 4
31-May 4 113 1 5
01-Jun 6 119 0 5
02-Jun 19 138 1 6
03-Jun 118 256 3 9
04-Jun 149 405 1 10
05-Jun 171 576 3 13
06-Jun 135 711 5 18
07-Jun 114 825 0 18
08-Jun 113 938 5 23
09-Jun 112 1,050 4 27
10-Jun 104 1,154 3 30
11-Jun 94 1,248 2 32
12-Jun 127 1,375 3 35
13-Jun 131 1,506 2 37
14-Jun 99 1,605 5 42
15-Jun 110 1,715 5 47
16-Jun 91 1,806 2 49
17-Jun 48 1,854 2 51
18-Jun 40 1,894 3 54
19-Jun 44 1,938 1 55
20-Jun 66 2,004 1 56
21-Jun 53 2,057 1 57
22-Jun 20 2,077 0 57
23-Jun 23 2,100 0 57
24-Jun 43 2,143 1 58
25-Jun 45 2,188 2 60
26-Jun 16 2,204 0 60
27-Jun 5 2,209 0 60
28-Jun 5 2,214 0 60
29-Jun 4 2,218 0 60
30-Jun 10 2,228 1 61
01-Jul 3 2,231 0 61
02-Jul 5 2,236 0 61
03-Jul 2 2,238 0 61
04-Jul 9 2,247 0 61
05-Jul 6 2,253 0 61
06-Jul 5 2,258 0 61
07-Jul 5 2,263 0 61
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix B – Page 11 October 2015
Table B-5. Continued.
Daily Cum.Dart Cum.
Date Count Count Tags Tags
09-Jul 0 2,266 0 61
10-Jul 0 2,266 0 61
11-Jul 1 2,267 0 61
12-Jul 1 2,268 0 61
13-Jul 4 2,272 0 61
14-Jul 3 2,275 0 61
15-Jul 2 2,277 0 61
16-Jul 0 2,277 0 61
17-Jul 3 2,280 0 61
18-Jul 0 2,280 0 61
19-Jul 2 2,282 0 61
20-Jul 0 2,282 0 61
21-Jul 1 2,283 0 61
22-Jul 2 2,285 0 61
23-Jul 2 2,287 0 61
24-Jul 2 2,289 0 61
25-Jul 2 2,291 0 61
26-Jul 0 2,291 0 61
27-Jul 1 2,292 0 61
28-Jul 1 2,293 0 61
29-Jul 2 2,295 0 61
30-Jul 3 2,298 0 61
31-Jul 0 2,298 0 61
01-Aug 0 2,298 0 61
02-Aug 0 2,298 0 61
03-Aug 1 2,299 0 61
04-Aug 0 2,299 0 61
05-Aug 0 2,299 0 61
06-Aug 1 2,300 0 61
07-Aug 1 2,301 0 61
08-Aug 1 2,302 0 61
09-Aug 1 2,303 0 61
10-Aug 0 2,303 0 61
11-Aug 0 2,303 0 61
12-Aug 0 2,303 0 61
13-Aug 0 2,303 0 61
14-Aug 0 2,303 0 61
15-Aug 0 2,303 0 61
16-Aug 0 2,303 0 61
17-Aug 1 2,304 0 61
18-Aug 0 2,304 0 61
19-Aug 0 2,304 0 61
20-Aug 0 2,304 0 61
21-Aug 0 2,304 0 61
22-Aug 1 2,305 0 61
Total 2,305 61
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 October 2015
Appendix C: Fixed-station receiver sites (setup and performance) and
mobile-tracking survey effort
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 1 October 2015
Table C-1. Location and antenna orientation of fixed-station receivers in the Susitna River drainage, 2014.
Site Location
Receiver
No.
Project
River Mile Latitude Longitude River Bank Antenna Antenna Orientation
Lower Yentna 12 61.66359 -150.62567 Right 1 Downstream Yentna River
2 Upstream Yentna River
Skwentna 14 61.87268 -151.35259 Right 1 Downstream Skwentna River
2 Upstream Skwentna River
Upper Yentna 17 62.16243 -151.53392 Left 1 Downstream Yentna River
2 Upstream Yentna River
Deshka Mouth 8 40 61.69127 -150.30632 Right 1 Downstream Sustina River
2 Upstream Susitna River
Sunshine 18 83 62.17300 -150.17428 Left 1 Downstream Sustina River
2 Upstream Susitna River
Talkeetna 9 62.34754 -150.01463 Left 1 Downstream Talkeetna River
2 Upstream Talkeetna River
Chulitna 29 62.55397 -150.23167 Left 1 Downstream Chulitna River
2 Upstream Chulitna River
Deshka Weir 20 61.78585 -150.34572 Right 1 Downstream Deshka River
2 Upstream Deshka River
Montana Creek Weir 27 62.10556 -150.04861 Right 1 Downstream Montana Creek
2 Upstream Montana Creek
Middle Fork Chulitna Weir 28 63.05900 -149.58222 Left 1 Downstream Middle Fork Chulitna River
2 Upstream Middle Fork Chulitna River
Lane Creek 5,10 117 62.52792 -150.11407 Right 1 Downstream Susitna River
2 Upstream Susitna River
3 Across Susitna River
Gateway 15 130 62.67645 -149.89303 Right 1 Downstream Susitna River
2 Upstream Susitna River
Indian River 25 142 62.78530 -149.65793 Right 1 Downstream Susitna River
2 Upstream Susitna River
3 Up Indian River
Cheechako 40 157 62.80794 -149.25392 Left 1 Downstream Susitna River
2 Upstream Susitna River
Chinook Creek 45 160 62.80176 -149.16079 Left 1 Downstream Susitna River
2 Upstream Susitna River
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FERC Project No. 14241 Appendix C – Page 2 October 2015
Table C-1. Continued.
Site Location
Receiver
No.
Project
River Mile Latitude Longitude River Bank Antenna Antenna Orientation
Devils Island 50 167 62.80926 -149.00268
Mainstem
island 1 Downstream Susitna River
2 Upstream Susitna River
Watana Dam site 56, 57 187 62.82342 -148.53477 Right 1 Downstream Susitna River
2 Upstream Susitna River
Watana Creek 59 197 62.82987 -148.25578 Right 1 Downstream Susitna River
2 Upstream Susitna River
3 Up Watana Creek
Kosina Creek 60 209 62.78389 -147.93802 Right 1 Downstream Susitna River
2 Upstream Susitna River
3 Up Kosina Creek
Oshetna River 65 235 62.63997 -147.38348 Left 1 Downstream Susitna River
2 Upstream Susitna River
3 Up Oshetna River
1 These stations were located primarily on tributaries; river bank orientations are with respect to the tributary not the Susitna River.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 3 October 2015
Table C-2. Monitoring efficiency (percent operational) of fixed-station receivers in the Lower River Basin in 2014, by week.
Week
Lower
Yentna
Upper
Yentna
Skwentna
River
Deshka
Mouth
Deshka
Weir
Montana
Weir
Sunshine
Mouth
Talkeetna
Station
Chulitna
Station
Middle
Chulitna
4/28 - 5/4 nd nd nd nd nd nd nd nd nd nd
5/5 - 5/11 nd nd nd nd nd nd nd nd nd nd
5/12 - 5/18 nd nd nd nd nd nd nd nd nd nd
5/19 - 5/25 100 nd nd 100 100 nd 100 nd nd nd
5/26 - 6/1 100 100 100 100 100 nd 100 100 nd nd
6/2 - 6/8 100 100 100 100 100 100 100 100 100 nd
6/9 - 6/15 100 100 100 100 100 100 100 100 100 nd
6/16 - 6/22 100 100 100 100 100 100 100 100 100 100
6/23 - 6/29 100 100 100 100 100 100 100 100 100 100
6/30 - 7/6 100 50 100 100 100 100 100 100 100 100
7/7 - 7/13 100 0 100 100 54 100 100 100 100 100
7/14 - 7/20 100 0 100 100 25 100 100 100 100 100
7/21 - 7/27 100 0 100 100 91 100 100 100 100 100
7/28 - 8/3 100 44 100 100 100 100 100 100 100 100
8/4 - 8/10 100 43 100 100 100 100 100 100 100 100
8/11 - 8/17 100 64 100 100 100 100 100 100 100 nd
8/18 - 8/24 100 13 100 100 100 100 100 100 100 nd
8/25 - 8/31 100 12 nd 100 100 100 100 100 100 nd
9/1 - 9/7 100 7 nd 100 100 100 100 100 100 nd
9/8 - 9/14 100 100 nd 100 nd 100 100 100 100 nd
9/15 - 9/21 100 nd nd 100 nd 100 100 100 100 nd
9/22 - 9/28 100 nd nd 100 nd 100 100 100 100 nd
9/29 - 10/5 nd nd nd nd nd nd nd nd nd nd
10/6 - 10/12 nd nd nd nd nd nd nd nd nd nd
10/13 - 10/19 nd nd nd nd nd nd nd nd nd nd
10/20 - 10/26 nd nd nd nd nd nd nd nd nd nd
10/27 - 11/2 nd nd nd nd nd nd nd nd nd nd
Notes:
Grey: Receiver not scanning; Red: Unknown malfunction.
Percentages were calculated as the number of hours of recorded receiver activity divided by the number of hours for which it was deployed, summed by week; "nd" = 'not
deployed'. Receivers were considered active in a given hour if at least one fish detection, beacon-tag hit, or noise event was recorded during the hour.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix C – Page 4 October 2015
Table C-3. Monitoring efficiency (percent operational) of fixed-station receivers in the Middle and Upper River basins in 2014, by week.
Week
Lane
Station
(LR Tags)
Lane
Station
(MR Tags)Gateway
Indian
River Cheechako Chinook
Devils
Station
Watana
Dam Site
Watana
Creek
Kosina
Creek
Oshetna
Creek
4/28 - 5/4 nd nd nd 100 nd nd nd nd nd 100 nd
5/5 - 5/11 nd nd nd 100 nd nd nd nd nd 100 nd
5/12 - 5/18 nd nd nd 100 nd nd nd nd nd 94 nd
5/19 - 5/25 100 100 nd 100 nd nd nd nd nd 78 100
5/26 - 6/1 100 100 nd 100 nd nd nd nd nd 100 100
6/2 - 6/8 99 100 nd 100 nd nd nd nd nd 100 100
6/9 - 6/15 100 100 100 100 100 100 34 nd 62 100 100
6/16 - 6/22 100 100 100 100 100 100 93 nd 91 100 100
6/23 - 6/29 100 9 100 100 100 100 99 nd 24 100 100
6/30 - 7/6 100 94 58 100 100 100 88 nd 79 100 100
7/7 - 7/13 100 100 100 100 100 100 100 100 100 100 100
7/14 - 7/20 100 100 100 100 100 100 100 100 100 100 100
7/21 - 7/27 100 100 100 100 100 100 100 100 100 100 100
7/28 - 8/3 100 100 100 100 100 100 74 100 100 100 100
8/4 - 8/10 100 100 100 100 100 100 100 100 100 100 100
8/11 - 8/17 100 100 100 100 100 100 100 100 100 100 100
8/18 - 8/24 100 100 100 100 100 100 100 100 100 100 100
8/25 - 8/31 100 100 100 100 100 100 100 100 100 100 100
9/1 - 9/7 100 100 100 100 100 100 100 30 100 100 100
9/8 - 9/14 100 100 100 100 100 100 100 94 100 100 100
9/15 - 9/21 100 100 100 100 100 100 100 100 100 100 100
9/22 - 9/28 100 100 100 100 100 100 100 100 100 100 100
9/29 - 10/5 100 100 nd 100 100 100 100 100 100 100 100
10/6 - 10/12 nd nd nd 100 100 nd 100 100 100 100 100
10/13 - 10/19 nd nd nd 100 nd nd 100 100 nd 100 nd
10/20 - 10/26 nd nd nd 100 nd nd 100 nd nd nd nd
10/27 - 11/2 nd nd nd 100 nd nd 100 nd nd nd nd
Notes:
Two receivers were deployed at Lane Station, one to monitor tags released in the lower river ('LR tags') and one for tags released in the middle river ('MR Tags').
Yellow: Low power/dead battery; Grey: Receiver not scanning; Orange: station damaged by wildlife.
Percentages were calculated as the number of hours of recorded receiver activity divided by the number of hours for which it was deployed, summed by week; "nd" = 'not deployed'.
Receivers were considered active in a given hour if at least one fish detection, beacon-tag hit, or noise event was recorded during the hour.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix C – Page 5 October 2015
Table C-4. List of the aerial telemetry surveys conducted in 2014, by location, date, and vehicle type (helicopter, fixed-wing).
Zone From:To:6-116-126-166-176-186-216-226-246-256-266-286-297-17-27-47-57-77-87-97-107-117-127-13MOB - Little Susitna River --
MOB - Beyond Confluence --H
MOB - Confluence - Yentna 3.5 32.4 H H F H H H F H
MOB - Yentna River 32.4 -H H H F F H H H F H
MOB - Yentna - Deshka 32.4 45.0 H H H F H H H F H
MOB - Deshka River 44.9 -H H H F H H H F H
MOB - Willow and Little Willow cr 52.2 55.6 H H H F H H H F H
MOB - Kashwitna River 64.7 -H H H H H H F H
MOB - Deshka - Kashwitna 45.0 64.7 H H H F H H H F H
MOB - Caswell Creek 67.4 -
MOB - Sheep Creek 70.1 -H H H H F H
MOB - Goose Creek 76.9 -F H
MOB - Kashwitna - Montana 64.7 80.7 H H H F H H H F H
MOB - Montana Creek 80.9 -H H H H H H F H
MOB - Montana - Sunshine 80.7 88.5 H H H F H H H F H
MOB - Sunshine Creek 88.1 -H H H H
MOB - Rabideux Creek 87.4 -H H H H H H H
MOB - Birch Creek 93.5 -
MOB - Talkeetna River 101.0 -H H H F H H H H F H
MOB - Chulitna River 101.7 -H H F H H H H F H
MOB - Sunshine - Talkeetna 88.5 102.3 H H H F H H H H H F H
MOB - Talkeetna - Lane 102.3 116.7 H H H H H H H H H H
MOB - Whiskers Creek 104.8 -H H H H H H H H H
MOB - Trib off zone 95 110.5 -
MOB - Lane - Gateway 116.7 130.1 H H H H H H H H H H H
MOB - Lane Creek 117.1 -H H H H H H
MOB - 5th of July Creek 127.3 -H
MOB - Slough 8A 129.2 129.8 H H H H H H H
MOB - Gateway - 4th of July 130.1 134.3 H H H H H H H H
MOB - Slough 9 131.4 133.5 H H H H H H
MOB - Sherman Creek 134.1 -
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix C – Page 6 October 2015
Table C-4. Continued.
Zone From:To:6-116-126-166-176-186-216-226-246-256-266-286-297-17-27-47-57-77-87-97-107-117-127-13MOB - 4th of July Creek 134.3 -H H H H H H H H
MOB - 4th of July - Slough 11 134.3 140.2 H H H H H H H H
MOB - Slough 11 138.6 -H H H H H H H
MOB - Gold Creek 140.1 -H H H H H H H H
MOB - Slough 11 - Indian 140.1 142.0 H H H H H H H H
MOB - Indian trib 141.8 -H H H H H H H H
MOB - Indian - Slough 21 142.0 145.7 H H H H H H H H
MOB - Slough 21 145.1 145.6 H H H H H H H H
MOB - above Powerline 145.7 146.0 H H H H H H H H
MOB - abv Powerline - Portage 146.0 152.3 H H H H H H H H H
MOB - Jack Long Creek 148.2 -H H H H H
MOB - Portage trib 152.3 -H H H H H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 H H H H H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.3 H H H H H H H H H H H H
MOB - Cheechako Creek 155.9 -H H H H H H H H H H
MOB - Cheechako - Impediment2 157.3 160.2 H H H H H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.4 H H H H H H H H H H H
MOB - Chinook Creek 160.4 -H H H H H H H
MOB - Chinook - Impediment3 160.4 164.8 H H H H H H H H H H H
MOB - Devils Creek 164.8 -H H H H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 H H H H H H H H H H H H
MOB - Devil Stn - Fog 166.9 179.4 H H H H H H
MOB - Fog Creek 179.3 -H H H H H H
MOB - Fog - Dam Site 179.4 187.2 H H H H H H
MOB - Tsusena Creek 184.5 -H H H H H H
MOB - Dam Site - Deadman 187.2 189.4 H H H H H H
MOB - Deadman Creek 189.4 -H H H H H
MOB - Deadman - Watana 189.4 196.9 H H H H H H
MOB - 'Creek 192'194.8 -H
MOB - Watana Creek 196.9 -H H H H H H H
MOB - Wantana - Kosina 196.9 209.2 H H H H H H
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix C – Page 7 October 2015
Table C-4. Continued.
Zone From:To:6-116-126-166-176-186-216-226-246-256-266-286-297-17-27-47-57-77-87-97-107-117-127-13MOB - Kosina Creek 209.2 -H H H H H H
MOB - Kosina - Jay Creek 209.2 211.0 H H H H H
MOB - Jay Creek 211.0 -H H H H H
MOB - Jay - Goose 211.0 232.9 H H H H H
MOB - Goose Creek (Upper River)232.9 -H H H H H
MOB - Goose - Oshetna 232.9 235.1 H H H H H
MOB - Oshetna River 235.1 -H H H H H
MOB - Oshetna - Tyone 235.1 247.3 H
MOB - Tyone River 247.3 -H
MOB - Tyone - Clearwater Cr 247.3 266.6
MOB - Clearwater Creek 266.6 -
MOB - above Clearwater Cr 266.6 -
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix C – Page 8 October 2015
Table C-4. Continued.
Zone From:To:7-147-167-177-197-207-217-227-237-257-267-287-297-318-18-38-48-58-68-78-88-98-108-11MOB - Little Susitna River --
MOB - Beyond Confluence --H H
MOB - Confluence - Yentna 3.5 32.4 H H F H H H F H H
MOB - Yentna River 32.4 -H H F H H H H F H F
MOB - Yentna - Deshka 32.4 45.0 H H F H H H F H H
MOB - Deshka River 44.9 -H H F/H H H F F/H H
MOB - Willow and Little Willow cr 52.2 55.6 H H F/H H H F F/H H
MOB - Kashwitna River 64.7 -H H F F/H H H F/H H
MOB - Deshka - Kashwitna 45.0 64.7 H H F H H H F H H
MOB - Caswell Creek 67.4 -H H H H H H
MOB - Sheep Creek 70.1 -H H F H H H H F/H H
MOB - Goose Creek 76.9 -H H F H H H F/H H
MOB - Kashwitna - Montana 64.7 80.7 H H F H H H H F H H
MOB - Montana Creek 80.9 -H H F H H H H F/H H
MOB - Montana - Sunshine 80.7 88.5 H H F H H H H H F H H
MOB - Sunshine Creek 88.1 -H H H H H H H H H
MOB - Rabideux Creek 87.4 -H H H H H H H H H H
MOB - Birch Creek 93.5 -H H H H H H
MOB - Talkeetna River 101.0 -H H F H H H H H H F H H
MOB - Chulitna River 101.7 -H H F H H H H H F F/H H
MOB - Sunshine - Talkeetna 88.5 102.3 H H F H H H H H H F H H
MOB - Talkeetna - Lane 102.3 116.7 H H H H H H H H H H
MOB - Whiskers Creek 104.8 -H H H H H H H H H
MOB - Trib off zone 95 110.5 -H
MOB - Lane - Gateway 116.7 130.1 H H H H H H H H H H H
MOB - Lane Creek 117.1 -H H H H H H H H H H
MOB - 5th of July Creek 127.3 -H H H
MOB - Slough 8A 129.2 129.8 H H H H H H H H H H
MOB - Gateway - 4th of July 130.1 134.3 H H H H H H H H H H
MOB - Slough 9 131.4 133.5 H H H H H H H H H H
MOB - Sherman Creek 134.1 -
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 9 October 2015
Table C-4. Continued.
Zone From:To:7-147-167-177-197-207-217-227-237-257-267-287-297-318-18-38-48-58-68-78-88-98-108-11MOB - 4th of July Creek 134.3 -H H H H H H H H H H
MOB - 4th of July - Slough 11 134.3 140.2 H H H H H H H H H H
MOB - Slough 11 138.6 -H H H H H
MOB - Gold Creek 140.1 -H H H H H H H H H H
MOB - Slough 11 - Indian 140.1 142.0 H H H H H H H H H H
MOB - Indian trib 141.8 -H H H H H H H H H H H
MOB - Indian - Slough 21 142.0 145.7 H H H H H H H H H H
MOB - Slough 21 145.1 145.6 H H H H H H H H H H
MOB - above Powerline 145.7 146.0 H H H H H H H H H H
MOB - abv Powerline - Portage 146.0 152.3 H H H H H H H H H H H
MOB - Jack Long Creek 148.2 -H H H H H H H H H H
MOB - Portage trib 152.3 -H H H H H H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 H H H H H H H H H H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.3 H H H H H H H H H H H H H H H H
MOB - Cheechako Creek 155.9 -H H H H H H H H H H H H H H H H
MOB - Cheechako - Impediment2 157.3 160.2 H H H H H H H H H H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.4 H H H H H H H H H H H H H H H H
MOB - Chinook Creek 160.4 -H H H H H H H H H H H H H H H H
MOB - Chinook - Impediment3 160.4 164.8 H H H H H H H H H H H H H H H H
MOB - Devils Creek 164.8 -H H H H H H H H H H H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 H H H H H H H H H H H H H H H H
MOB - Devil Stn - Fog 166.9 179.4 H H H H H H H
MOB - Fog Creek 179.3 -H H H H H
MOB - Fog - Dam Site 179.4 187.2 H H H H H H
MOB - Tsusena Creek 184.5 -H H H H H
MOB - Dam Site - Deadman 187.2 189.4 H H H H H
MOB - Deadman Creek 189.4 -H H H H H
MOB - Deadman - Watana 189.4 196.9 H H H H H
MOB - 'Creek 192'194.8 -H
MOB - Watana Creek 196.9 -H H H H H
MOB - Wantana - Kosina 196.9 209.2 H H H H H
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 10 October 2015
Table C-4. Continued.
Zone From:To:7-147-167-177-197-207-217-227-237-257-267-287-297-318-18-38-48-58-68-78-88-98-108-11MOB - Kosina Creek 209.2 -H H H H
MOB - Kosina - Jay Creek 209.2 211.0 H H H
MOB - Jay Creek 211.0 -H H H
MOB - Jay - Goose 211.0 232.9 H H
MOB - Goose Creek (Upper River)232.9 -H H H
MOB - Goose - Oshetna 232.9 235.1 H H H
MOB - Oshetna River 235.1 -H H
MOB - Oshetna - Tyone 235.1 247.3 H
MOB - Tyone River 247.3 -H
MOB - Tyone - Clearwater Cr 247.3 266.6 H
MOB - Clearwater Creek 266.6 -H
MOB - above Clearwater Cr 266.6 -H
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 11 October 2015
Table C-4. Continued.
Zone From:To:8-128-138-158-168-178-188-198-218-228-248-258-278-288-298-308-319-29-39-49-59-69-89-9MOB - Little Susitna River --
MOB - Beyond Confluence --H H H
MOB - Confluence - Yentna 3.5 32.4 H F H H H H F/H H H
MOB - Yentna River 32.4 -H F H H H H H F/H H H
MOB - Yentna - Deshka 32.4 45.0 H H F H H H H H F/H H H
MOB - Deshka River 44.9 -H H F H H H H H F/H H H
MOB - Willow and Little Willow cr 52.2 55.6 H H F H H H H H H F H H
MOB - Kashwitna River 64.7 -H H F H H H H H H F H H
MOB - Deshka - Kashwitna 45.0 64.7 H H F H H H H H F/H H H
MOB - Caswell Creek 67.4 -H H H H H H H H H
MOB - Sheep Creek 70.1 -H H F H H H H H F H H
MOB - Goose Creek 76.9 -H H F H H H H H H F H H
MOB - Kashwitna - Montana 64.7 80.7 H H F H H H H H F/H H H
MOB - Montana Creek 80.9 -H H F H H H H H H F H H
MOB - Montana - Sunshine 80.7 88.5 H H F H H H H H F/H H H
MOB - Sunshine Creek 88.1 -H H H H H H H H H H
MOB - Rabideux Creek 87.4 -H H H H H H H H H H
MOB - Birch Creek 93.5 -H H H H H H H H H H
MOB - Talkeetna River 101.0 -H H F F/H H H H H F/H H H
MOB - Chulitna River 101.7 -H H F F/H H H H H F H H
MOB - Sunshine - Talkeetna 88.5 102.3 H H F H H H H H F/H H H H
MOB - Talkeetna - Lane 102.3 116.7 H H H H H H H H H H
MOB - Whiskers Creek 104.8 -H H H H H H H H H H
MOB - Trib off zone 95 110.5 -H
MOB - Lane - Gateway 116.7 130.1 H H H H H H H H H H H H
MOB - Lane Creek 117.1 -H H H H H H H H H H
MOB - 5th of July Creek 127.3 -H H H H H H
MOB - Slough 8A 129.2 129.8 H H H H H H H H H H
MOB - Gateway - 4th of July 130.1 134.3 H H H H H H H H H H
MOB - Slough 9 131.4 133.5 H H H H H H H H H H
MOB - Sherman Creek 134.1 -
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 12 October 2015
Table C-4. Continued.
Zone From:To:8-128-138-158-168-178-188-198-218-228-248-258-278-288-298-308-319-29-39-49-59-69-89-9MOB - 4th of July Creek 134.3 -H H H H H H H H H H
MOB - 4th of July - Slough 11 134.3 140.2 H H H H H H H H H H
MOB - Slough 11 138.6 -H H H H H H H H H H
MOB - Gold Creek 140.1 -H H H H H H H H H H
MOB - Slough 11 - Indian 140.1 142.0 H H H H H H H H H H
MOB - Indian trib 141.8 -H H H H H H H H H H
MOB - Indian - Slough 21 142.0 145.7 H H H H H H H H H H
MOB - Slough 21 145.1 145.6 H H H H H H H H H H
MOB - above Powerline 145.7 146.0 H H H H H H H H H H
MOB - abv Powerline - Portage 146.0 152.3 H H H H H H H H H H
MOB - Jack Long Creek 148.2 -H H H H H H H H H H
MOB - Portage trib 152.3 -H H H H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 H H H H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.3 H H H H H H H H H H
MOB - Cheechako Creek 155.9 -H H H H H H H H H H
MOB - Cheechako - Impediment2 157.3 160.2 H H H H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.4 H H H H H H H H H H
MOB - Chinook Creek 160.4 -H H H H H H H H H H
MOB - Chinook - Impediment3 160.4 164.8 H H H H H H H H H H
MOB - Devils Creek 164.8 -H H H H H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 H H H H H H H H H H
MOB - Devil Stn - Fog 166.9 179.4 H H H H H H H
MOB - Fog Creek 179.3 -H H H H H H H
MOB - Fog - Dam Site 179.4 187.2 H H H H H H
MOB - Tsusena Creek 184.5 -H H H H
MOB - Dam Site - Deadman 187.2 189.4 H H H H H
MOB - Deadman Creek 189.4 -H H H H H
MOB - Deadman - Watana 189.4 196.9 H H H H H
MOB - 'Creek 192'194.8 -H H
MOB - Watana Creek 196.9 -H H H H H
MOB - Wantana - Kosina 196.9 209.2 H H H H H H
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 13 October 2015
Table C-4. Continued.
Zone From:To:8-128-138-158-168-178-188-198-218-228-248-258-278-288-298-308-319-29-39-49-59-69-89-9MOB - Kosina Creek 209.2 -H H H H H H
MOB - Kosina - Jay Creek 209.2 211.0 H H H H
MOB - Jay Creek 211.0 -H H H
MOB - Jay - Goose 211.0 232.9 H H H H
MOB - Goose Creek (Upper River)232.9 -H H H H
MOB - Goose - Oshetna 232.9 235.1 H H H H
MOB - Oshetna River 235.1 -H H H H
MOB - Oshetna - Tyone 235.1 247.3 H
MOB - Tyone River 247.3 -
MOB - Tyone - Clearwater Cr 247.3 266.6 H
MOB - Clearwater Creek 266.6 -
MOB - above Clearwater Cr 266.6 -
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 14 October 2015
Table C-4. Continued.
Zone From:To:9-119-149-159-169-179-189-209-219-239-249-259-3010-110-210-710-810-910-1410-1510-1610-1710-2810-2910-30MOB - Little Susitna River --
MOB - Beyond Confluence --H H H
MOB - Confluence - Yentna 3.5 32.4 H H H H H H H
MOB - Yentna River 32.4 -H H H H H H H
MOB - Yentna - Deshka 32.4 45.0 H H H H H H H
MOB - Deshka River 44.9 -H H F H H H H H
MOB - Willow and Little Willow cr 52.2 55.6 H F H H H H H H
MOB - Kashwitna River 64.7 -H F H H H H H H H
MOB - Deshka - Kashwitna 45.0 64.7 H F H H H H H H H
MOB - Caswell Creek 67.4 -H H H H H H H
MOB - Sheep Creek 70.1 -H F H H H H H H H
MOB - Goose Creek 76.9 -H F H H H H H H
MOB - Kashwitna - Montana 64.7 80.7 H F H H H H H H H
MOB - Montana Creek 80.9 -H F H H H H H H H
MOB - Montana - Sunshine 80.7 88.5 H H H F H H H H H
MOB - Sunshine Creek 88.1 -H H H H H H H H
MOB - Rabideux Creek 87.4 -H H H H H H H H
MOB - Birch Creek 93.5 -H H H H H H H
MOB - Talkeetna River 101.0 -H H H F H H H H H
MOB - Chulitna River 101.7 -H H H F H H H H H H
MOB - Sunshine - Talkeetna 88.5 102.3 H H H F H H H H H H H
MOB - Talkeetna - Lane 102.3 116.7 H H H H H H H H
MOB - Whiskers Creek 104.8 -H H H H H H H H H
MOB - Trib off zone 95 110.5 -
MOB - Lane - Gateway 116.7 130.1 H H H H H H H H H H H
MOB - Lane Creek 117.1 -H H H H H H H H H H
MOB - 5th of July Creek 127.3 -H H
MOB - Slough 8A 129.2 129.8 H H H H H H H H H H H
MOB - Gateway - 4th of July 130.1 134.3 H H H H H H H H H H H
MOB - Slough 9 131.4 133.5 H H H H H H H H H H H
MOB - Sherman Creek 134.1 -
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 15 October 2015
Table C-4. Continued.
Zone From:To:9-119-149-159-169-179-189-209-219-239-249-259-3010-110-210-710-810-910-1410-1510-1610-1710-2810-2910-30MOB - 4th of July Creek 134.3 -H H H H H H H H H H
MOB - 4th of July - Slough 11 134.3 140.2 H H H H H H H H H H H
MOB - Slough 11 138.6 -H H H H H H H H H H H
MOB - Gold Creek 140.1 -H H H H H H H H H
MOB - Slough 11 - Indian 140.1 142.0 H H H H H H H H H H H
MOB - Indian trib 141.8 -H H H H H H H H H H H
MOB - Indian - Slough 21 142.0 145.7 H H H H H H H H H H H
MOB - Slough 21 145.1 145.6 H H H H H H H H H H H
MOB - above Powerline 145.7 146.0 H H H H H H H H H H H
MOB - abv Powerline - Portage 146.0 152.3 H H H H H H H H H H H
MOB - Jack Long Creek 148.2 -H H H H H H H H H
MOB - Portage trib 152.3 -H H H H H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 H H H H H H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.3 H H H H H H H H H H H
MOB - Cheechako Creek 155.9 -H H H H H H H H H
MOB - Cheechako - Impediment2 157.3 160.2 H H H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.4 H H H H H H H H H
MOB - Chinook Creek 160.4 -H H H H H H H H
MOB - Chinook - Impediment3 160.4 164.8 H H H H H H H H H
MOB - Devils Creek 164.8 -H H H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 H H H H H H H H H
MOB - Devil Stn - Fog 166.9 179.4 H H H
MOB - Fog Creek 179.3 -H H H
MOB - Fog - Dam Site 179.4 187.2 H H H
MOB - Tsusena Creek 184.5 -H H H
MOB - Dam Site - Deadman 187.2 189.4 H H H
MOB - Deadman Creek 189.4 -H H H
MOB - Deadman - Watana 189.4 196.9 H H H
MOB - 'Creek 192'194.8 -H
MOB - Watana Creek 196.9 -H H H
MOB - Wantana - Kosina 196.9 209.2 H H H
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix C – Page 16 October 2015
Table C-4. Continued.
Zone From:To:9-119-149-159-169-179-189-209-219-239-249-259-3010-110-210-710-810-910-1410-1510-1610-1710-2810-2910-30MOB - Kosina Creek 209.2 -H H H
MOB - Kosina - Jay Creek 209.2 211.0 H H H
MOB - Jay Creek 211.0 -H H H
MOB - Jay - Goose 211.0 232.9 H H H
MOB - Goose Creek (Upper River)232.9 -H H H
MOB - Goose - Oshetna 232.9 235.1 H H H
MOB - Oshetna River 235.1 -H H H
MOB - Oshetna - Tyone 235.1 247.3 H H H
MOB - Tyone River 247.3 -H H H
MOB - Tyone - Clearwater Cr 247.3 266.6
MOB - Clearwater Creek 266.6 -
MOB - above Clearwater Cr 266.6 -
PRM Survey Date (m-d)
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 October 2015
Appendix D: Spawning destinations
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix D – Page 1 October 2015
Table D-1. Summary of monitoring effort at potential spawning sites, by species, as part of the Habitat
Suitability Criteria (HSC) component of the Fish and Aquatics Instream Flow Study (RSP Section 8.5), 2014.
Survey Date Presence Spawning Presence Spawning Presence Spawning
11-Aug
Slough 10 North Fork
Slough 10 East Fork
Slough 9A
4th of July Side Channel X
12-Aug
Oxbow 1
Unnamed Slough RR (PRM 121.3 )
Slough 9
5th of July Slough
13-Aug
4th of July Side Channel X
4th of July Creek Mouth X X
Sherman Creek Mouth
Skull Creek Mouth
Deadhorse Creek Mouth
Oxbow 2
14-Aug
Jack Long Creek Mouth
Indian River Mouth X X
Slough 22 X X
30-Aug
Unnammed Slough RL (near PRM 119)
Mainstem RL a (near PRM 114)
Oxbow 1
Slough 22 X X X X
31-Aug
Slough 21
Slough 19 X X X X
Slough 16
Slough 15
Slough 10 North Fork X
Slough 10 East Fork X X
Slough 9A X X
Side Channel (PRM 131.5)X X
Side Channel(PRM 137)X X
Notes:
a Sample site located bewteen Gash Creek and Oxbow 1.
RL indicates a sampling site located on river left; RR indicates a site on river right.
Sockeye Pink Chum
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix D – Page 2 October 2015
Table D-2. Summary of monitoring effort at potential spawning sites for Chinook Salmon in the Middle River, 2014.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Presence Holding Spawning
1 681 Lane Creek Tributary Mouth 20-Jul DIDSON X
2a 515 Lane Creek - Gateway Side Channel 20-Jul Boat
*Aerial
3 373, 749, 677 5th of July Creek Tributary Mouth *Aerial
4 663 Lane Creek - Gateway Main Channel NA Boat
5 319 4th of July Creek Tributary Mouth 20-Jul DIDSON X
25-Jul DIDSON X
6 809 4th of July Side Channel Side Channel 19-Jul DIDSON X
20-Jul Boat/Visual X
7a 233 Gateway - Slough 11 Main Channel 19-Jul Boat
8a 673 Slough/Side Channel 10 Side Channel 19-Jul Boat
9a 768 Slough/Side Channel 11 Side Channel 19-Jul Boat/Visual
10 291, 634, 708 Gateway - Slough 11 Main Channel 23-Jul DIDSON X
11 695 Gold Creek Tributary Mouth 21-Jul Boat X
12a 335 Slough 11 - Slough 21 Side Channel 23-Jul Boat
13 cluster Indian River Tributary Mouth 22-Jul DIDSON X
14a 714 Slough 11 - Slough 21 Main Channel NA NA
15a 390, 540 Side Channel 21 Side Channel *Boat/Aerial
16 444 Slough 21 - Portage Creek Main Channel NA NA
17 cluster Portage Creek Tributary Mouth 21-Jul DIDSON X
25-Jul DIDSON X
18a 5531 Chinook Creek Tributary Mouth *Aerial
a Indicates a site that was visually assessed and considered too difficult to access with boat-mounted DIDSON.
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Too turbid to assess
Site not surveyed
Site not surveyed
Site not surveyed
Site not visited
Too turbid to assess
Site not visited
Site not surveyed
Fish Observed
Site not surveyed
Too turbid to assess
Too turbid to assess
Site not visited
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix D – Page 3 October 2015
Table D-3. Summary of monitoring effort at potential spawning sites for Chum Salmon in the Middle River, 2014.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Presence Holding Spawning
1 2024 Talkeetna - Lane Creek Main Channel *Aerial
2 2628 Lane Creek - Gateway Side Channel *Aerial
3 2201 5th of July Creek Tributary Mouth 12-Aug HSC X
*Aerial X
4 3331 Slough 8D Slough *Aerial X
5 3082 Slough 8A Slough 10-Sep Aerial X X
24-Sep HSC X X
6 1923 Gateway - Slough 11 Side Channel *Aerial/Boat
7 1998, 2120, 2169 Slough 9 Slough 12-Aug HSC X
8 2981 4th of July Creek Tributary Mouth 13-Aug HSC X
*Aerial X
9 2078, 3238, 3426 4th of July Side Channel Side Channel 11-Aug HSC X
13-Aug HSC X
10 2929 Slough 11 - Indian River Main Channel *Aerial/Boat
11 2177 Slough 11 - Indian River Main Channel *Aerial/Boat
12 2746 Indian River Tributary Mouth 14-Aug HSC X
10-Sep Aerial X X
13 3094 Indian River - Slough 21 Main Channel *Aerial/Boat
14 2329 Portage Creek Tributary Mouth *Aerial X
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Too turbid to assess
Fish Observed
Too turbid to assess
Too turbid to assess
Too turbid to assess
Too turbid to assess
Too turbid to assess
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix D – Page 4 October 2015
Table D-4. Summary of monitoring effort at potential spawning sites for Coho Salmon in the Middle River, 2014.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Presence Holding Spawning
1a 3639 Lane Creek - Gateway Main Channel *Aerial
2 2901 Oxbow 2 Side Channel *Aerial/Boat
3 2932, 3371 Gateway - Slough 11 Side Channel *Aerial X
4 1830 Slough 13 Slough *Aerial X
5 1881 Slough 11 - Indian River Main Channel *Aerial X
6 3370, 3398 Indian River Tributary Mouth *Aerial X
7 3396 Slough 22 Slough 30-Aug HSC X
8 1960 Portage Creek Tributary Mouth 10-Sep Aerial X
a Indicates a site that was visually assessed and not considered suitable for spawning based on physical characteristics
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Fish Observed
Too turbid to assess
Too turbid to assess
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix D – Page 5 October 2015
Table D-5. Summary of monitoring effort at potential spawning sites for Pink Salmon in the Middle River, 2014.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Presence Holding Spawning
1 1709, 1856 Side Channel 6A Side Channel *Boat/Aerial
2 2019 5th of July Creek Tributary Mouth 12-Aug HSC X
3 1663, 1664, 2926 4th of July Creek Tributary Mouth 11-Aug HSC X X
13-Aug HSC X X
4 2432 4th of July Side Channel Side Channel 11-Aug HSC X
13-Aug HSC X
5 2423 Gateway - Slough 11 Main Channel *Boat/Aerial
6 1537 Slough 11 - Slough 21 Side Channel *Boat/Aerial
7 1300, 2033 Indian River Tributary Mouth 14-Aug HSC X X
8 2198 Side Channel 21 Side Channel *Boat/Aerial
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Fish Observed
Too turbid to assess
Too turbid to assess
Too turbid to assess
Too turbid to assess
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix D – Page 6 October 2015
Table D-6. Summary of monitoring effort at potential spawning sites for Sockeye Salmon in the Middle River, 2014.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Presence Holding Spawning
1 2056 Slough 8D Slough *Aerial X
2 cluster Slough 8A Slough 10-Sep Aerial X X
24-Sep HSC X X
3 cluster Slough 9 Slough 12-Aug HSC X
4 1392, 1914, 2076 4th of July Side Channel Side Channel 11-Aug HSC X
13-Aug HSC X
5 cluster Slough 10 Slough 11-Aug HSC X
31-Aug HSC X X
23-Sep HSC X X
6 cluster Slough 11 Slough 10-Sep Aerial X X
21-Sep HSC X X
7 cluster Slough/Side Channel 21 Slough/SideChannel 30-Aug Aerial X X
31-Aug HSC X
10-Sep Aerial X X
22-Sep HSC X X
8 cluster Slough 22 Slough 14-Aug HSC X
30-Aug HSC X X
b Indicates a site that was visually assessed and not considered suitable for spawning based on physical characteristics
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Fish Observed
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix D – Page 7 October 2015
Table D-7. Details of impediment-passage events for radio-tagged fish, 2014.
Chinook Salmon (≥ 50 cm) that Passed Impediment 3
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
537 20 Jul 20 Jul 4 Aug 4.5 0.5 8.0 21,400 21,400 16,400
787 20 Jul 20 Jul 30 Jul 2.5 0.5 5.5 21,400 21,400 15,900
Average 20 Jul 20 Jul 2 Aug 3.5 0.5 6.8 21,400 21,400 16,150
Chinook Salmon (≥ 50 cm) That Passed Impediment 2 but not Impediment 3
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
17 30 Jun 30 Jun -1.0 0.5 4.5 19,600 19,600 -
139 24 Jul 28 Jul -7.0 1.0 d.n.a.18,100 16,800 -
222 6 Jul 18 Jul -1.0 0.5 17.0 23,800 19,000 -
516 1 Aug 1 Aug -10.5 0.5 d.n.a.16,000 16,000 -
882 25 Jul 1 Aug -4.5 0.5 d.n.a.17,900 16,000 -
903 23 Jul 24 Jul -0.5 0.5 10.5 18,100 18,100 -
5531 18 Jul 18 Jul -2.5 0.5 13.0 19,000 19,000 -
Average 18 Jul 22 Jul 3.9 0.6 11.3 18,929 17,786
Chinook Salmon (≥ 50 cm) That Passed Impediment 1 but not Impediment 2
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
221 20 Jul --4.5 d.n.a.-21,400 --
828 18 Jul --2.5 d.n.a.-19,000 --
868 23 Jul --5.5 d.n.a.-18,100 --
5702 1 Jul --3.0 d.n.a.-23,300 --
Average 16 Jul 3.9 -20,450
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix D – Page 8 October 2015
Table D-7. Continued.
Chinook Salmon (≥ 50 cm) That Approached Impediment 1 but did not Pass
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
23 ---3.0 -----
33 ---4.5 -----
40 ---1.5 -----
91 ---4.5 -----
103 ---25.5 -----
108 ---5.0 -----
111 ---4.5 -----
166 ---1.5 -----
198 ---1.5 -----
237 ---4.0 -----
239 ---1.5 -----
244 ---13.5 -----
264 ---7.5 -----
300 ---2.5 -----
359 ---1.5 -----
562 ---1.5 -----
611 ---2.5 -----
621 ---12.0 -----
668 ---0.5 -----
716 ---0.5 -----
818 ---1.0 -----
5242 ---2.0 -----
5255 ---3.0 -----
5384 ---5.5 -----
5408 ---1.5 -----
Average 4.5
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FERC Project No. 14241 Appendix D – Page 9 October 2015
Table D-7. Continued.
Chinook Salmon (< 50 cm) That Approached Impediment 1 but did not Pass
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
574 ---1.5 -----
Average -1.5 -
Sockeye Salmon That Passed Impediment 1 but not Impediment 2
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
785 27 Jul --0.5 d.n.a.-18,900 --
955 8 Sep --1.0 d.n.a.-14,400 --
2214 8 Sep --3.0 d.n.a.-14,400 --
Average 25 Aug 1.5 -15,900
Sockeye Salmon That Approached Impediment 1 but did not Pass
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
647 ---1.5 -----
837 ---1.5 -----
1053 ---1.5 -----
1260 ---20.5 -----
1293 ---2.5 -----
1346 ---1.5 -----
1404 ---1.5 -----
1851 ---3.0 -----
2076 ---3.5 -----
2156 ---1.0 -----
2157 ---10.5 -----
2606 ---5.5 -----
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix D – Page 10 October 2015
Table D-7. Continued.
Sockeye Salmon That Approached Impediment 1 but did not Pass
Tag
Number
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3
Hold Time
Below I1
(d)
Hold Time
Below I2
(d)
Hold Time
Below I3
(d)
Flow at I-1
Passage
(cfs)
Flow at I-2
Passage
(cfs)
Flow at I-3
Passage
(cfs)
2770 ---7.0 -----
Average 4.7
Notes:
Details include the date of first detections above each impediment, the duration of holding time below each impediment, and the flow (measured at Tsusena Creek) at
the time of the first detection upstream of the impediment. "d.n.a" = Did Not Approach next upstream impediment. Top panel: Chinook salmon (≥ 50 cm) that passed
Impediment 3. Second panel: Chinook salmon (≥ 50 cm) that passed Impediment 2, but not Impediment 3. Third panel: Chinook salmon (≥ 50 cm) that passed
Impediment 1, but not Impediment 2. Fouth panel: Chinook salmon (≥ 50 cm) that approached within 1 km of Impediment 1, but did not pass. Fifth panel: Chinook
salmon (< 50 cm) that approached within 1 km of Impediment 1, but did not pass. Sixth panel: Sockeye salmon that passed Impediment One, but not Impediment
Two. Seventh panel: Sockeye salmon that approached within 1 km of Impediment 1, but did not pass.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix D – Page 11 October 2015
Table D-8. Number of Chinook Salmon counted during aerial spawner surveys, by location and survey period, 2014.
River Section Waterbody
Miles
Surveyed
Jul 14 -
Jul 15
Jul 19 -
Jul 20
Jul 25 -
Jul 26
Jul 31 -
Aug 1
Aug 6 -
Aug 7
Aug 12 -
Aug 13
Aug 18-
Aug 19
Between Impediment 1 & 2 Cheechako Creek Susitna 155.9 2.4 11 16 8 13 7 0 0
Between Impediment 2 & 3 Chinook Creek Susitna 160.4 8.7 0 5 5 2 2 0 0
Middle River -Devil Creek Susitna 164.8 2.5 0 0 0 2 10 5 2
Above Impediment 3 Fog Creek Susitna 179.3 19.3 0 0 0 3 2 0 1
Fog Creek Tributary L1 Fog 5.1 7.6 0 0 0 0 0 0 0
Bear Creek Susitna 184.0 5.7 0 0 0 0 0 0 0
Bear Creek Tributary R1 Bear 0.8 8.2 0 0 0 0 0 0 0
Tsusena Creek Susitna 184.4 3.6 0 0 0 0 0 0 0
Upper River -Deadman Creek Susitna 188.4 0.3 0 0 0 0 0 0 0
Within Reservoir Watana Creek Susitna 196.9 21.3 0 0 0 0 0 0 0
Watana Creek Tributary
R5 Watana 8.6 8.6 0 0 0 0 0 0 0
Kosina Creek Susitna 209.2 18.8 0 0 0 0 0 0 0
Gilbert Creek Kosina 6.2 6 0 NS2 NS2 0 0 0 0
Tsisi Creek Kosina 7.3 6.4 0 NS2 0 0 0 0 NS1
Tsisi Lake 1 Tsisi 7.2 2.8 NS1 NS1 0 0 0 0 0
Tsisi Lake 2 Tsisi 10.6 5.2 NS1 NS1 0 0 0 0 0
Jay Creek Susitna 211.0 13.3 0 0 0 0 0 0 0
Upper River -Goose Creek Susitna 232.9 11.2 0 0 0 0 0 0 0
Above Reservoir Oshetna River Susitna 235.1 26.3 0 0 0 0 NS2 0 0
Black River Oshetna 6.2 0 0 0 0 NS2 0
1 No survey - surveys targeting Sockeye Salmon began July 25-26.
2 No survey - high and/or turbid water prevented survey.
Confluence
Project River
Mile
Survey Dates
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FERC Project No. 14241 Appendix D – Page 12 October 2015
Table D-9. Summary of weather variability during the adult salmon aerial spawner surveys in the Middle
and Upper rivers, 2014.
Table D-10. Summary of survey condition rankings during the adult salmon aerial spawner surveys in the
Middle and Upper rivers, 2014.
Date Sunny
Partly
Cloudy Overcast Showers Rain Wind
July 14-15 X X X X
July 19-20 X X X
July 25-26 X X X X X
July 31-Aug 1 X X X X
Aug 6-7 X X X
Aug 12-13 X X
Aug 18-19 X X X X
Weather Condition
Variable Average Rank
Observed
Range
Standard
Deviation
Sun Glare 4 3 to 4 0.5
Water clarity 3 0 to 4 0.8
Vegetation Cover 3 1 to 4 0.8
Notes:
Variables were ranked from 0 to 4, with 4 being optimal and 0 being poor.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix D – Page 13 October 2015
Figure D-1. Destinations for radio-tagged Chinook Salmon released in the Lower River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination. Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections, that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 14 October 2015
Figure D-2. Destinations for radio-tagged Chinook Salmon released in the Middle River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections, that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 15 October 2015
Figure D-3. Destinations for radio-tagged Chum Salmon released in the Lower River in 2012. Proportions
classified to tributary destinations are shown in yellow circles. The proportion classified to any mainstem
destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion of fish that
were tracked but that could not be conclusively assigned to a destination Proportions are calculated from the
total numbers of tags released, after excluding fish with one or fewer detections, that never moved, or moved
only downstream.
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FERC Project No. 14241 Appendix D – Page 16 October 2015
Figure D-4. Destinations for radio-tagged Chum Salmon released in the Middle River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections, that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 17 October 2015
Figure D-5. Destinations for radio-tagged Coho Salmon released in the Lower River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections, that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 18 October 2015
Figure D-6. Destinations for radio-tagged Coho Salmon released in the Middle River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 19 October 2015
Figure D-7. Destinations for radio-tagged Pink Salmon released in the Lower River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections, that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 20 October 2015
Figure D-8. Destinations for radio-tagged Pink Salmon released in the Middle River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections, that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 21 October 2015
Figure D-9. Destinations for radio-tagged Sockeye Salmon released in the Lower River in 2012. Proportions
classified to tributary destinations are shown in yellow circles. The proportion classified to any mainstem
destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion of fish that
were tracked but that could not be conclusively assigned to a destination Proportions are calculated from the
total numbers of tags released, after excluding fish with one or fewer detections, that never moved, or moved
only downstream.
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FERC Project No. 14241 Appendix D – Page 22 October 2015
Figure D-10. Destinations for radio-tagged Sockeye Salmon released in the Middle River in 2012-2014.
Proportions classified to tributary destinations are shown in yellow circles. The proportion classified to any
mainstem destination is shown in an arbitrarily-placed pink circle. In the green circle shows the proportion
of fish that were tracked but that could not be conclusively assigned to a destination Proportions are
calculated from the total numbers of tags released, after excluding fish with one or fewer detections, that
never moved, or moved only downstream.
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FERC Project No. 14241 Appendix D – Page 23 October 2015
Figure D-11. Potential mainstem spawning sites for radio-tagged Chinook Salmon in the Lower River, PRM
40–104, 2012-2014. Red dots indicate locations of individual radio-tagged fish.
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FERC Project No. 14241 Appendix D – Page 24 October 2015
Figure D-12. Potential mainstem spawning sites for radio-tagged Chinook Salmon in the Middle River (red
and yellow dots), PRM 103–157, 2012 - 2014. Colored dots (red, yellow, or green) indicate individual radio-
tagged fish. Green dots also include locations that did not have a radio-tagged fish, but spawning was
confirmed during opportunistic surveys. Black dots indicate spawning locations by project river mile
confirmed during historic surveys (summarized in Barrett et al. 1985a,b and Thompson et al. 1986). Multiple
green dots within an inset indicate a location that was confirmed for spawning and not each individual fish.
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FERC Project No. 14241 Appendix D – Page 25 October 2015
Figure D-13. Potential mainstem spawning sites for radio-tagged Chum Salmon in the Lower River, PRM
103–157, 2012 - 2014. Colored dots (red, yellow, or green) individual radio-tagged fish. Black dots indicate
spawning locations confirmed during historic surveys (summarized in Barrett et al. 1985a,b and Thompson et
al. 1986).
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FERC Project No. 14241 Appendix D – Page 26 October 2015
Figure D-14. Potential mainstem spawning sites for radio-tagged Chum Salmon in the northern half of the
Middle River, PRM 40–104, 2012 - 2014. Colored dots (red, yellow, or green) indicate individual radio-
tagged fish. Green dots also include locations that did not have a radio-tagged fish, but spawning was
confirmed during opportunistic surveys. Black dots indicate spawning locations by project river mile
confirmed during historic surveys (summarized in Barrett et al. 1985a,b and Thompson et al. 1986). Multiple
green dots within an inset indicate a location that was confirmed for spawning and not each individual fish.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix D – Page 27 October 2015
Figure D-15. Potential mainstem spawning sites for radio-tagged Chum Salmon in the southern half of the
Middle River, PRM 103–157, 2012 -2014. Colored dots (red, yellow, or green) indicate individual radio-
tagged fish. Green dots also include locations that did not have a radio-tagged fish, but spawning was
confirmed during opportunistic surveys. Black dots indicate spawning locations by project river mile
confirmed during historic surveys (summarized in Barrett et al. 1985a,b and Thompson et al. 1986). Multiple
green dots within an inset indicate a location that was confirmed for spawning and not each individual fish.
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FERC Project No. 14241 Appendix D – Page 28 October 2015
Figure D-16. Potential mainstem spawning sites for radio-tagged Coho Salmon in the Lower River, PRM 40–
104, 2012 - 2014. Red dots represent individual radio-tagged fish. Black dots indicate spawning locations
confirmed during historic surveys (summarized in Barrett et al. 1985a,b and Thompson et al. 1986).
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FERC Project No. 14241 Appendix D – Page 29 October 2015
Figure D-17. Potential mainstem spawning sites for radio-tagged Coho Salmon in the Middle River, PRM
103–157, 2012 - 2014. Colored dots (red, yellow, or green) indicate individual radio-tagged fish. Green dots
also include locations that did not have a radio-tagged fish, but spawning was confirmed during opportunistic
surveys. Black dots indicate spawning locations by project river mile confirmed during historic surveys
(summarized in Barrett et al. 1985a,b and Thompson et al. 1986). Multiple green dots within an inset indicate
a location that was confirmed for spawning and not each individual fish.
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FERC Project No. 14241 Appendix D – Page 30 October 2015
Figure D-18. Potential mainstem spawning sites for radio-tagged Pink Salmon in the Lower River, PRM103–
157, 2012 -2014. Red dots represent individual radio-tagged fish.
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FERC Project No. 14241 Appendix D – Page 31 October 2015
Figure D-19. Potential mainstem spawning sites for radio-tagged Pink Salmon in the Middle River, PRM
103–157, 2012 - 2014. Colored dots (red, yellow, or green) indicate individual radio-tagged fish. Green dots
also include locations that did not have a radio-tagged fish, but spawning was confirmed during opportunistic
surveys. Black dots indicate spawning locations by project river mile confirmed during historic surveys
(summarized in Barrett et al. 1985a,b and Thompson et al. 1986). Multiple green dots within an inset indicate
a location that was confirmed for spawning and not each individual fish.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix D – Page 32 October 2015
Figure D-20. Potential mainstem spawning sites for radio-tagged Sockeye Salmon in the Middle River, PRM
103–157, 2012 - 2014. Colored dots (red, yellow, or green) indicate individual radio-tagged fish. Green dots
also include locations that did not have a radio-tagged fish, but spawning was confirmed during opportunistic
surveys. Black dots indicate spawning locations by project river mile confirmed during historic surveys
(summarized in Barrett et al. 1985a,b and Thompson et al. 1986). Multiple green dots within an inset indicate
a location that was confirmed for spawning and not each individual fish.
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 October 2015
Appendix E: Radio Tag Recoveries
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix E – Page 1 October 2015
Table E-1. Radio tag recovery information for fish released in the Lower River and Yentna River, 2014.
Species Tag Date Recovery
(Release Location)Number Recovered Description Latitude Longitude Method
Chinook Salmon,5245 23 Jun Clear Cr., Talkeetna trib.62.3799 -150.0162 angler
METF ≥ 50 cm 5285 22 Jun Deshka River mouth 61.6976 -150.3173 angler
(Lower River)5337 30 Jun Clear Creek (Chunilna), river mile 1.75 62.3799 -150.0162 angler
5340 14 Jun Deshka River 61.7294 -150.3192 angler
5374 18 Jun Deshka River mouth 61.6976 -150.3173 angler
5378 18 Jun Deshka River 61.7294 -150.3192 angler
5402 31 May Deshka River mouth 61.6976 -150.3173 angler
5416 4 Jun Deshka River mouth 61.6976 -150.3173 angler
5476 16 Jun Deshka River mouth 61.6976 -150.3173 angler
5492 1 Jul Deshka River, river mile 17 61.7886 -150.3398 angler
5494 30 Jun Lake Creek mouth 61.9092 -150.9096 angler
5552 15 Jun Susitna R., 3/4 mi. below Montana Cr.62.0720 -150.1022 angler
5563 11 Aug Peters Creek, 8mi. upstream from Petersville bridge 62.4611 -150.7463 angler
5566 5 Aug Middle Fork Chulitna River, by Parks Highway crossing 63.2553 -149.2454 angler
5686 14 Jul Sheep Creek mouth 61.9712 -150.0875 angler
5693 1 Jul Deshka River, 3 miles up 61.7418 -150.3119 angler
5755 14 Jun Deshka River above river mile 7 61.7886 -150.3398 angler
5757 13 Jun Deshka River mouth 61.6976 -150.3173 angler
5774 14 Jun Deshka River mouth 61.6976 -150.3173 angler
5871 14 Jun Deshka River mouth 61.6976 -150.3173 angler
5876 14 Jun Deshka River 61.7294 -150.3192 angler
5881 22 Jun Deshka River, 3/4mi. below Laub's homestead 61.7475 -150.3215 angler
5889 1 Aug Deception Creek, at Four Mile Road 61.7479 -149.9343 field crew
5893 25 Jun Deshka River, 2 mi. upstream 61.7294 -150.3192 angler
Chinook Salmon,6513 28 Jul Lake Creek 61.9307 -150.9127 angler
METF ≥ 50 cm 6696 11 Jul Lake Cr. about 1 mi. upstream from Yentna 61.9307 -150.9127 angler
(Yentna River)6724 20 Jun Yentna River, mouth of Lake Cr.61.9092 -150.9096 angler
6753 16 Jun Yentna River, mouth of Lake Creek, McDougal Slough 61.9092 -150.9096 angler
Recovery Location 1
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix E – Page 2 October 2015
Table E-1. Continued.
Species Tag Date Recovery
(Release Location)Number Recovered Description Latitude Longitude Method
Coho Salmon 5298 30 Jul Little Willow Creek 61.8101 -150.1020 angler
(Lower River)5300 1 Aug Deshka River mouth 61.6976 -150.3173 angler
5398 21 Aug Talkeetna River 62.3393 -150.1042 angler
5946 11 Aug Sunshine Creek 62.1782 -150.1032 angler
5983 24 Aug Trapper Creek [assume at the mouth]62.2551 -150.1723 angler
5985 8 Aug Deshka mouth 61.6976 -150.3173 angler
6031 22 Aug Talkeetna River, foot of Mainstem 62.3287 -150.1136 angler
6055 9 Aug Talkeetna River, 2.5 miles upstream 62.3484 -150.0578 angler
6105 9 Aug Talkeenta River 62.3393 -150.1042 angler
6108 18 Jul Deshka River mouth 61.6976 -150.3173 angler
6127 1 Aug Deshka River 61.7294 -150.3192 angler
6137 4 Aug Willow Creek mouth 61.7833 -150.1671 angler
6140 6 Aug Kashwitna River, 0.25 up from mouth 61.9146 -150.0964 angler
6156 24 Aug Trapper Creek [assume at the mouth]62.2531 -150.1680 angler
6157 16 Aug Rabideux Creek mouth 62.1750 -150.1933 angler
6182 16 Aug Clear Creek 62.3799 -150.0162 angler
6202 4 Aug Whiskers Creek 62.3770 -150.1720 angler
6210 15 Aug Deshka River (Moose Creek at Oilwell Rd.)61.7538 -150.3265 angler
6213 15 Aug Clear Creek 62.3799 -150.0162 angler
6244 6 Aug Deshka mouth 61.6976 -150.3173 angler
6253 21 Aug Talkeetna River, ~2 miles up 62.3463 -150.0754 angler
6260 10 Aug Clear Creek mouth (Chunilna)62.3799 -150.0162 angler
6260 31 Aug Clear Creek (Talkeenta River)62.3799 -150.0162 angler
6264 1 Aug Deshka River mouth 61.6976 -150.3173 angler
6285 27 Aug Kashwitna River, 0.5 mile up from RR Bridge 61.9383 -150.0455 angler
6296 15 Aug Willow Creek mouth 61.7833 -150.1671 angler
6341 11 Aug Montana Creek mouth 62.1045 -150.0757 angler
6393 23 Aug Talachulitna, Mouth 61.8658 -151.4143 angler
6413 20 Aug Troublesome Creek, Mouth 62.6546 -150.2399 angler
6420 15 Aug Deshka River, about 1 mile upstream 61.7294 -150.3192 angler
Recovery Location 1
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Table E-1. Continued.
Species Tag Date Recovery
(Release Location)Number Recovered Description Latitude Longitude Method
Coho Salmon 6429 16 Aug Sunshine Creek, 100 yards above Susitna confluence 62.1782 -150.1032 angler
(Lower River)6459 31 Jul Deshka River 61.7294 -150.3192 field crew
6488 17 Aug Little Willow mouth 61.7986 -150.1519 angler
6489 17 Aug Montana Creek mouth 62.1045 -150.0757 angler
6495 19 Aug Sheep Creek 61.9915 -150.0725 angler
6498 29 Aug Talkeetna River 62.3393 -150.1042 angler
Coho Salmon 6806 24 Aug Deshka River, ~4 miles up 61.7538 -150.3265 other
(Yentna River)6851 6 Aug Deshka weir 61.7856 -150.3450 field crew
Pink Salmon 5058 6 Aug Willow Creek, downstream of Deception Creek mouth 61.7788 -150.1259 angler
(Lower River)5174 30 Jul Montana Creek 62.1056 -150.0486 angler
1 Recovery coordinates were estimated based on the site description; radio tag recoveries only.
Recovery Location 1
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Table E-2. Radio tag recovery information for fish released in the Middle River, 2014.
Tag Date Recovery
Species Number Recovered Description Latitude Longitude Method
Chinook Salmon 48 16 Jul Indian River 62.8263 -149.6484 other
(METF ≥ 50 cm)48 16 Jul Indian River 62.8263 -149.6484 other
160 19 Aug Indian River (mile 266.7 on RR)62.8394 -149.6435 other
245 3 Jul Susitna River at Indian 62.7845 -149.6596 angler
297 7 Aug Twin Bridges South of Curry 62.8394 -149.6435 angler
333 1 Jul LGL Fishwheel 3 62.6374 -149.9775 field crew
388 2 Jul LGL Fishwheel 3 62.6374 -149.9775 field crew
459 25 Aug LGL Fishwheel 3 62.6374 -149.9775 field crew
564 29 Jul LGL Fishwheel 3 62.6374 -149.9775 field crew
590 29 Jul LGL Fishwheel 3 62.6374 -149.9775 field crew
739 22 Jul LGL Fishwheel 3 62.6374 -149.9775 field crew
806 3 Oct Mouth of Jack Long 62.8227 -149.4976 other
812 10 Aug Indian River mouth 62.7845 -149.6596 angler
Chum Salmon 1680 4 Sep 4th of July Mouth 62.7156 -149.8053 field crew
Coho Salmon 2130 22 Aug Portage Creek 62.8384 -149.3741 angler
2810 27 Aug Talkeetna River, just below Clear Creek 62.3799 -150.0162 angler
Pink Salmon 1664 4 Sep 4th of July Mouth 62.7156 -149.8053 field crew
2073 20 Aug Montana Creek Weir 62.1056 -150.0486 field crew
Sockeye Salmon 1346 26 Sep in a slough at PRM141 62.7832 -149.6696 other
1927 12 Oct RM 145, ouside Slough 21 62.8137 -149.5802 other
1950 7 Aug Larson Creek 62.3708 -149.8563 angler
2330 10 Oct Chase Creek 62.4447 -150.1321 other
2609 11 Sep Disappointment Creek (trib to Talkeetna R)62.4556 -149.6672 other
1 Recovery coordinates were estimated based on the site description
Recovery Location 1
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Appendix F: Tracking histories of chinook salmon above Impediment 3
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Table F-1. Summary of migration and spawning behavior for radio-tagged Chinook Salmon after they passed Impediment 3, 2012–2014.
Max Max Max Max Total
Tag Capture Length Spawning First Last Upstream Upstream Downstream Downstream Live
Number Date (cm)Sex Area Live Live Days Location Distance Days Location Distance Days Days1
2012
27 22 Jun 78 TL Undetermined Chinook 28 Jul 5 Aug 8 Kosina Mouth 80 11 Curry 60 8 26
52 25 Jun 89 TL Undetermined Kosina 20 Jul 9 Aug 20 ------28
94 29 Jun 81 TL Undetermined Devil 23 Jul 5 Aug 13 Fog 30 4 Cheechako 19 12 31
104 29 Jun 66 TL Undetermined Portage 24 Jul 30 Jul 6 Above Devil Creek 30 10 ---10
113 30 Jun 84 TL Undetermined Kosina 26 Jul 7 Aug 12 ------19
219 2 Jul 73 TL Male Kosina 23 Jul 26 Jul 3 Above Kosina 30 1 ---7
246 3 Jul 85 TL Female Kosina 23 Jul 26 Jul 3 ------6
257 3 Jul 89 TL Female Portage 30 Jul 17 Aug 18 Devil Creek 24 13 ---28
266 4 Jul 101 TL Male Portage 24 Jul 6 Aug 13 Near Fog 44 15 ---19
359 6 Jul 93 TL Male Portage 6 Aug 11 Aug 5 Kosina 93 26 ---25
5005 26 May -Undetermined Kosina 23 Jul 31 Jul 8 ---Portage 103 16 30
5019 28 May 87 MEF Undetermined Kosina 23 Jul 11 Aug 19 ------24
2013
241 21 Jun 64 MEF Undetermined Unknown -30 Aug -Near headwater --Below Talkeetna --45
272 23 Jun 64 MEF Undetermined Devils 30 Jul 12 Aug 14 Devils Creek 0 0 Devils Creek 0 0 13
395 26 Jun 65 MEF Undetermined Tsesena 22 Jul 1 Aug 11 near Deadman Creek 6.5 1 Tsusena Creek 0 0 19
2014
537 4 Jul 80 MEF Male Unknown -9 Aug -Just Above I-3 -----36
787 11 Jul 78 MEF Undetermined Kosina 2 Aug 18 Aug *17 *Oshetna 40 5 ---20 *
* Motion sensor malfunctioned. Mortality date is approximate.
1 Total days the fish was alive after passing Impediment 3 (accounts for the 1 day that tags must be motionless before going into mortality mode).
Notes:
Distances are in kilometers (1 km = 0.62 mi)
Spawning Period Explorations Before Spawning Downstream After Spawning
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Figure F-1. Tracking history of a radio-tagged Chinook Salmon (tag #537) that was detected above Impediment 3, PRM 123–167, 2014.
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Figure F-2. Tracking history of a radio-tagged Chinook Salmon (tag #787) that was detected above Impediment 3, PRM 97–245, 2014.
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Figure F-3. Tracking history of a radio-tagged Chinook Salmon (tag #27) that was detected above Impediment 3, 2012.
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Figure F-4. Tracking history of a radio-tagged Chinook Salmon (tag #52) that was detected above Impediment 3, 2012.
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Figure F-5. Tracking history of a radio-tagged Chinook Salmon (tag #94) that was detected above Impediment 3, 2012.
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Figure F-6. Tracking history of a radio-tagged Chinook Salmon (tag #104) that was detected above Impediment 3, 2012.
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Figure F-7. Tracking history of a radio-tagged Chinook Salmon (tag #113) that was detected above Impediment 3, 2012.
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Figure F-8. Tracking history of a radio-tagged Chinook Salmon (tag #219) that was detected above Impediment 3, 2012.
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Figure F-9. Tracking history of a radio-tagged Chinook Salmon (tag #246) that was detected above Impediment 3, 2012.
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Figure F-10. Tracking history of a radio-tagged Chinook Salmon (tag #257) that was detected above Impediment 3, 2012.
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Figure F-11. Tracking history of a radio-tagged Chinook Salmon (tag #266) that was detected above Impediment 3, 2012.
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Figure F-12. Tracking history of a radio-tagged Chinook Salmon (tag #359) that was detected above Impediment 3, 2012.
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Figure F-13. Tracking history of a radio-tagged Chinook Salmon (tag #5005) that was detected above Impediment 3, 2012.
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Figure F-14. Tracking history of a radio-tagged Chinook Salmon (tag #5019) that was detected above Impediment 3, 2012.
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Figure F-15. Tracking history of a radio-tagged Chinook Salmon (tag #241) that was detected above Impediment 3, 2013.
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Figure F-16. Tracking history of a radio-tagged Chinook Salmon (tag #272) that was detected above Impediment 3, 2013.
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Figure F-17. Tracking history of a radio-tagged Chinook Salmon (tag #395) that was detected above Impediment 3, 2013.
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Appendix G: Counts of chinook salmon at Watana Canyon using sonar
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1. INTRODUCTION
The Alaska Energy Authority (AEA) has selected a site for the proposed development of a
hydroelectric dam within Watana Canyon on the Upper Susitna River. The degree to which fish,
in particular adult salmon, use this area as a migration corridor is currently uncertain. Reliable
estimates of the number of fish that migrate through Watana Canyon will help describe the
potential impacts on fishery resources of constructing and operating a hydropower project.
Additionally, information regarding fish use of Watana Canyon as a migration corridor will
inform discussions concerning fish passage facilities at the hydropower project.
In its study plan determination (SPD), the FERC (Federal Energy Regulatory Commission)
requested that AEA modify Study 9.7 to include an evaluation of the future feasibility of
counting fish at or near the Watana Dam Site as follows (FERC 2013a, page B-20):
“We recommend the study be modified to require AEA to include in the initial study
report an evaluation, based on site-specific data obtained during the 2013 study
season, of the feasibility of putting in a weir or sonar counting station at or near the
dam site during the 2014 study season to provide an accurate count of any resident
or anadromous fish that are successfully able to migrate upstream through Devils
Canyon in the project area.”
AEA followed up on FERC’s recommendation and determined that operation of a weir near the
dam site was not feasible due to the physical impossibility of any structure handling the normal
levels and range of discharge for the mainstem Susitna River. Further, it did not appear feasible
to provide an accurate count of resident fish, or to know if a fish has migrated upstream through
Devils Canyon (except for anadromous adult salmon).
In 2013, the study team assessed the feasibility of placing a sonar counting station at or near the
dam site (see Appendix G in AEA 2014c). Given several assumptions, it was likely feasible to
count salmon-sized fish (50 cm [19.7 in] TL or greater) in Watana Canyon, in particular Chinook
Salmon, and to quantify the accuracy of those counts using corroboration with the passage of
radio-tagged Chinook Salmon (Appendix G in AEA 2014c).
In 2014, the study team implemented the methods for achieving the objectives of sonar
monitoring near the proposed Watana Dam site as described in the ISR. This appendix report
describes the use of multi-beam imaging sonar for estimating the number of Chinook Salmon
(fish 50 cm [19.7 in] TL or greater), as well as those measuring less than 50 cm (19.7 in) TL, that
passed the proposed Watana Dam Site from July 6 to August 22, 2014. In addition, the study
team collected bathymetry and water velocity profiles at the monitoring sites.
2. Study Goal and Objectives
Following FERC’s recommendations, the primary goal of the study as modified by the feasibility
assessment was to provide an accurate count of anadromous fish (specifically Chinook Salmon)
near the proposed dam site (i.e., Watana Canyon). The specific objectives for this study were to:
1. Estimate the number of net upstream-moving Chinook Salmon that passed through the
sonar beams; and
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2. Describe temporal (daily and hourly) and spatial (range of passage) patterns of Chinook
Salmon observations.
3. STUDY AREA
The study area was located in the Upper Susitna River near the location of the proposed Watana
Dam Site. The section of river is characterized by a single channel with steep canyon walls,
undisturbed forested areas, and gravel bars with occasional sand bars.
4. METHODS
4.1. Site Selection
A reconnaissance flight was conducted on July 5, 2014, to assess the suitability of various
locations for setting up sonar count stations. A location immediately downstream of the
proposed Watana Dam Site at PRM 187.2 was determined to be the most suitable within the
areas that were accessible. To find the optimal location for sonar sampling along the selected
reach, an ARIS 1200 unit was used on July 6, 2014 to map the bathymetry along multiple
transects from the right and left banks. Bottom-profiling allows for determination of optimal
sonar alignment and aiming angles, and determination of the presence of depressions or troughs
in the field-of-view (FOV) that would allow for fish to move past the sonar undetected (Maxwell
and Smith 2007; Faulkner and Maxwell 2009). A single sonar location was established on each
side of the river just below the proposed Watana Dam Site (Figure G-1).
4.2. Data Collection
ARIS systems were used to monitor for Chinook Salmon escapement from each side of the river.
Two different models of ARIS units were used: the ARIS 1200, which has operating frequencies
of 0.7 and 1.2 megahertz (MHz), was installed on the left bank. The ARIS 1800, which has
operating frequencies of 1.1 and 1.8 MHz, was installed on the right bank. Each ARIS system
consisted of the sonar head, data transmission cable, switch box, Ethernet cable, laptop computer
and an external hard drive.
The sonar heads were deployed using aluminum H-mounts equipped with boat-trailer jacks that
allowed for adjustment of sonar tilt angles. The mounts were typically positioned 5 to 10 ft from
the edge of the wetted width (Figure G-2). The sonar heads were typically positioned between
0.2 and 1.5 ft off the bottom, aimed towards the opposite bank and tilted down to allow the
sampling beams to spread across the substrate throughout the majority of the sampling windows.
Sand bags filled with cobble and gravel were placed on the feet of the mounts to keep them
secured to the substrate. The mounts, depth of sonar heads and tilt angles were adjusted
periodically as river levels fluctuated throughout the study. Rock wall barriers were constructed
to prevent fish from passing behind the mounts. Electronic components were housed in
aluminum environmental boxes fastened to trees above mean high water level (Figure G-3). The
systems were powered using banks of six, 6-V batteries that were recharged each day with
Honda 2000 gasoline-powered generators.
Data were acquired using ARISScope software (version 1.0 for the 1800 unit and version 2.0 for
the 1200 unit, SoundMetrics Corp., Bellevue, WA). Data collection started at the left bank
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station at 4:51 P.M. on July 6 and at 12:12 P.M. on July 7 at the right bank station (see Table G-1
for sample site details). Data were collected continuously in consecutive 10-minute files until
the study period ended on August 22 (with the exception of the period 10:40 A.M. on July 30
through 1:45 P.M. on August 7 when the left bank station was shut down). Data were ported
directly to 1-terabyte external hard drives. Hard drives were changed daily and the data were
backed up and archived to additional hard drives each day.
The maximum sample ranges used were based on the extent to which substrate was visible in the
FOVs. The gradually sloping bottom along the left bank allowed for substrate to be evident out
to 37 m (121.4 ft) in range, whereas the bottom dropped off at 16 m (52.4 ft) in range along the
right bank (Figure G-4). Seeing substrate throughout the FOV ensures that no depressions or
troughs exist that would allow for fish to move past the ensonified area undetected. An aerial
photograph of the sampling locations with depictions of the ensonified areas in plan -view is
shown in Figure G-5. Operating frequencies and typical data collection parameters used for the
two sonar stations are shown in Table G-2. There were sometimes slight adjustments to data
collection parameters when mounts where repositioned to accommodate variable river levels (see
Table G-6 for daily data collection parameters).
4.3. Data Processing
Processing of ARIS data involved reviewing the data files using ARISFish software (version 1.0,
SoundMetrics Corp.). Technicians in the field reviewed files by displaying the data in echogram
form, which is a visual representation of the entire image file with time plotted along the
horizontal axis and range plotted along the vertical axis. Fish targets that move across the FOV
are shown as tracks. Reviewers scrolled through the echograms to locate tracks, and when tracks
were observed the tracks were framed with the cursor to prompt the sonar imagery of the track to
display (see Figure G-6 for example of this process). Sonar images of fish were enlarged and
fish lengths were estimated using the software’s sizing tool.
Fish targets were classified as resident fish or Chinook Salmon based on their estimated size.
Chinook Salmon were defined as any fish targets that were 50 cm (19.7 in) or greater in
estimated total length. For each Chinook Salmon detected, the following parameters were
recorded: estimated total length, range at first and last detection, and direction of travel. Lengths
of some fish could not be estimated when they passed immediately in front of the sonar units. If
greater than or equal to 50 cm TL (19.7 in) of length could be measured for targe ts larger than
the width of the FOV, then these fish were classified as Chinook with an unknown estimated
length. Any fish targets measuring less than 50 cm (19.7 in) TL were not classified by species,
and only their estimated total length was recorded. The accuracy of length measurements from
the sonar data is approximately ± 10 percent based on known targets.
Level-three quality control on the data review process was conducted in three steps by a senior
scientist with sonar expertise:
1. All Chinook Salmon targets identified by field technicians were reviewed to ensure that
each observation was accurate with respect to estimated size, first and last detected range,
and direction of travel;
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2. All resident fish targets identified by field technicians and classified as being 40 to 49 cm
(15.7–19.3 in) in estimated length were reviewed to ensure that none of these targets
exceeded 49 cm (19.3 in) and thus should be classified as Chinook Salmon; and
3. Ten percent of the sonar data files from each day and from both monitoring stations were
randomly selected and processed (as described above) to assess whether any Chinook
Salmon observations were missed during the in-field review.
4.4. River Discharge
Discharge data for the Upper Susitna River reported here were obtained from United States
Geological Survey (USGS) gauge at Tsusena Creek.
4.5. Current Velocity and Bathymetry Profiles
To support further assessment of the fish migration corridor at the sample reach, seven ADCP
transects were measured at approximately 80-ft intervals along the reach (Figure G-5). The
ADCP surveys were conducted on August 15, 2014. To supplement the velocity transects,
bathymetric data were collected on August 16, 2014 using an Odom CV-100 echosounder and a
TopCon GPS receiver along transects associated with sonar data collection (Transects 3 and 6).
AEA (2014b) provides detailed methods associated with ADCP and bathymetry data collection.
5. RESULTS
5.1. River Discharge
During sonar operations from July 6 to August 22, Susitna River flows at the Tsusena Creek
gauge ranged from 14,200 to 35,300 cfs (Figure 4.1-3; 16,700–36,500 cfs at the Gold Creek
gauge). Discharge in the Upper Susitna River generally decreased during the sonar sampling
period after a peak of 35,300 cfs at the Tsusena Creek gauge on July 8 (36,500 cfs at the Gold
Creek gauge). Periodic increases in discharge occurred in mid to late July. Throughout August,
discharge remained below 19,000 cfs at the Tsusena Creek gauge (below 22,000 cfs at the Gold
Creek gauge).
5.2. Sampling Effort
With the exception of the period from July 30 through August 7 when the left bank station was
demobilized, both stations operated continuously throughout the sample period (Figure G-7).
5.3. Sonar Coverage
After initial setup of the sonar systems, the left bank station ensonified an estimated 41.5 percent
of the wetted channel width and the right bank station ensonified an estimated 16.1 percent of the
wetted channel width (Table G-3). With respect to overall scope, the systems covered 57.6
percent of the wetted channel widths, leaving 42.4 percent of the thalweg section of the river
uncovered with sonar. Proportional coverage increased slightly as the mounts were periodically
moved further out as water surface elevation decreased through the sampling period.
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Cross-sectional coverage of the water column throughout the sampling ranges of the left and
right bank sonar systems is shown in Figure G-8. The bottom profiles along the main axes of the
sampling areas shown in Figure G-8 are based on geo-referenced data collected during the
bathymetry surveys. The cross-sectional sonar coverage shown in Figure G-8 is conceptual
given that the sonar heads were re-positioned and re-aimed throughout the study to accommodate
changing river levels. The sonar systems sampled along the substrate throughout the entire range
for the right bank sonar and 97 percent for the left bank sonar (see Figure G-4). Portions of the
water column near the water surface at both locations were not sampled (top 2 ft) given the shape
of the channel relative to the height of the sample volume.
5.4. Chinook Salmon Counts
A total of 24 net upstream-migrating (26 upstream, 2 downstream) Chinook Salmon were
counted at the sonar stations in 2014 (Table G-4). The first fish was observed on July 10 and last
fish was observed on August 22. On a daily basis, Chinook counts ranged from 0 to 3, and
counts greater than 0 generally coincided with decreasing or stabilized river discharge (Figure G-
9). Twenty-two of the 24 fish (92 percent) were observed with the right bank sonar station.
On an hourly basis, the distribution of fish counts indicated no apparent diel passage patterns
(Figure G-10). All fish detections were within 4 m (13.1 ft) from the sonar units with most
occurring at 3 m (9.8 ft) in range (Figure G-11). Size estimates for upstream migrants ranged
from 50 to 110 cm (19.7–43.3 in), with an average of 78 cm (30.7 in).
In addition, 213 fish measuring 40–49 cm (15.7–19.3 in) TL, and 1,044 fish measuring less than
40 cm TL (15.7 in), were counted at the sonar stations (direction of movement for these fish was
not recorded). These fish could not be identified to species using sonar. For fish which were
less than 50 cm (19.7 in) TL, a percentage of these fish could potentially be small Chinook
Salmon (as based on measurements at the Middle River fishwheels (minimum 27 cm [10.6 in]
METF; see Figure A-29). However, the potential species as based on sampling from Study 9.5,
and in order of likelihood in the observed size range, are Arctic grayling, burbot, round
whitefish, and longnose sucker.
5.5. Water Velocity and Bathymetry Profiles
A plot of serial water velocity profiles below the Watana dam site and along the reach of river
where sonar sampling was conducted shows a general trend of lower velocities near the
shorelines and higher velocities in the main channel (Figures G-12 to G-14). Comparing near-
shore velocities between the left and right bank indicates that, with the exception of Transect 2,
the River Right shorelines had lower velocities across a broader area than did the River Left
shorelines. Transect 2 was unique among all transects in that the River Right edge terminated at
a steep canyon wall that extended out onto a point (see Figure G-5). Velocities along River
Right were typically less than 5 ft/s (1.5 m/s), whereas velocities along River Left were often
greater than 5 ft/s. Velocities within the main channel often exceeded 10 ft/s (3 m/s) with
transects 6 and 7 exhibiting the highest velocities. The river channel is characterized as having
relatively steep banks that slope off to the maximum depth within 50 ft of ordinary high water
level and a relatively flat in between (Figure G-15).
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The velocity data were spatially integrated and represented as transect-specific discharge
estimates (Table G-5). The discharge estimates provide measures of precision and accuracy on
the velocity data.
6. DISCUSSION
One hundred percent sonar coverage of the river width at PRM 182.1 was not possible in 2014
given the technical limitations of the sonar equipment and the physical bathymetry of the river.
The maximum range at which 50 cm (19.7 in) TL targets can be detected with the ARIS 1200
unit is about 40 m (131 ft) and with the ARIS 1800 about 35 m (115 ft). Even with the most
suitable bottom topography that would allow coverage along the substrate to the maximum
ranges, coverage would still not achieve 100 percent. With the two ARIS units used in 2014, an
estimated 58 percent of the river width was sampled. The sonar coverage was scaled to the
extent of visible substrate. The un-sampled 42 percent consisted of primarily the middle of the
river channel. The lack of complete sonar coverage creates uncertainty around the fish counts
and raises two important questions – 1) Is there a more suitable location in the canyon that would
provide higher proportional sonar coverage of the river width and thus less uncertainty around
estimates of abundance?, and 2) How likely is it that some fish passed undetected in 2014
through the Watana Canyon in the main river channel beyond the maximum ranges sampled?
Given the gradient and morphological features controlling the rivers width and depth in much of
the Upper River, finding a location with a gradual and uniform substrate slope from river right to
left that has a wetted width within the range needed for 100 percent sonar coverage is very
unlikely. An aerial reconnaissance survey in 2014 did not identify any new potential sonar sites.
All potential locations with a wetted width closer to the range needed for 100 percent sonar
coverage had unsuitable bottom profiles and depths for the multi-beam sonar technology to
provide effective coverage. Many locations are inaccessible by helicopter, and others provide no
option for a site installation, even by boat, due to the steep rock walls present along many
sections of the river. There may be suitable locations below Tsusena Creek, but establishing
count stations below a major tributary creates uncertainty regarding whether the fish detected at
the site will spawn above the Watana Dam site or up in the tributary. Presently, the count
stations established in 2014 are the most suitable locations for monitoring fish passage above the
dam site with sonar.
To address the question of whether fish may have passed the count stations undetected beyond
the sampling ranges used in 2014, it is informative to examine water velocity and bathymetry
profile across the width of the river to understand the physical environment and potential fish
migration corridors. Bathymetry and velocity surveys were conducted at seven transects in the
river reach in which sonar data were collected during the 2014 sample period. Profile data from
these surveys provide important information collected concurrently with the sonar data to help
determine potential migration corridors and aid in assessing effectiveness of the sonar sampling
near the dam site.
The 2014 water velocity profiles (Figures G-12 to G-14) indicate higher water velocities with
increasing distance from shore, and generally, a greater extent of lower water velocities along the
right bank as compared with the left bank. Given the availability of low water velocity areas
along the banks (especially along the right bank) as compared with the high velocities observed
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FERC Project No. 14241 Appendix G – Page 7 October 2015
throughout the main channel, it is likely the primary migration corridors in this section of river
are along the banks. The velocity is too high for a majority of the channel to be conducive to
fish passage. Further, there does not appear to be any unique bathymetry which would provide a
corridor for passage except for relatively close to the banks (Figure G-15). It is important to
point out that the velocity data were collected when discharge of the river was 14,900 cfs. This
level of discharge reflects river conditions throughout much of the latter half of the study, but
does not reflect conditions earlier in the study period when discharge was considerably higher.
Nonetheless, it likely that the general pattern of high velocities in the main channel and lower
velocities along the banks would persist at higher flow levels.
Overall, the precision of the velocity data was estimated to be within 1–2 percent, but the
accuracy of the data showed a slight negative bias relative to USGS gauge data (D. Brailey,
Brailey Hydrologic Consultants, pers. comm). Data are being evaluated across the past three
years relative to USGS data to quantify accuracy of the velocity data; the current estimate is
about a 1 to 2 percent negative bias.
With respect to the likelihood of fish passing through the canyon in the high-velocity areas
beyond the reach of the sonar count stations, it is instructive to review what is known about
swimming speeds and capabilities of migrant adult salmon. Previous research on Chinook
Salmon swimming capabilities (Watts 1974; Bell 1986) suggest a sustained swimming speed
(normal function for long periods of time without fatigue) of 0.0–3.4 ft/s (0.0 to 1.0 m/s), and a
prolonged swimming speed (sustainable for 15 s to 200 s) of 3.1–10.8 ft/s (1.0 to 3.3 m/s). A
swimming speed of greater than 10.8 ft/s (3.3 m/s) is considered sustainable for 15 s or less. At
river discharges of 27,600 cfs and greater, based on the presumed swimming capabilities of
Chinook Salmon and the measured water velocities shown in Figures G-13 and G-14, fish
passage along the river right and river left banks would not be expected outside of 65 ft (20 m)
and 33 ft (10 m) from shore, respectively. The ADF&G does not have any data that suggest
Chinook Salmon negotiate flows greater than 9.8 ft/s (3 m/s) at any of their sonar sampling
locations throughout the state, but they do not rule out the possibility (Debby Burwen and Bruce
McIntosh, ADF&G, pers. comm., July 7, 2014).
The fish count data collected in 2014 support the general notion that migrating salmon use low
velocity areas as migration corridors when available. The highly skewed distribution of counts
towards the right bank as compared with the left bank follows the 2014 velocity profile patterns
that show greater proportions of low velocity areas along the right bank as compared with the left
bank. Additionally, the distribution of counts as a function of distance from the sonar units
indicates that fish passage through the canyon was shore-oriented with all detections occurring
within 4 m (13.1 ft) of the units. If some fish did migrate up through the main channel
undetected, it is reasonable to assume that the distribution of counts would have included
detections further out in range from the sonar units. The sonar data, together with velocity
profile data and known swimming capabilities of salmon, suggest there is a low probability that
some fish passed through the canyon undetected due to incomplete sonar coverage.
To aid in assessing efficiency of the sonar systems, two telemetry receiver stations were
deployed about 300 feet upstream from the sonar units on the right bank. One tagged Chinook
Salmon was detected by the receivers at 11:19 P.M. on July 31. Unfortunately the timing of this
detection coincided with the period in which the left bank count station had been demobilized.
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There were no sonar detections of fish measuring 50 cm (19.7 in) TL or greater from the right
bank station around the time of the detected tagged fish. Presumably that fish passed along the
left bank, or less likely up the main channel. Due to the limited number of tagged fish that
migrated up as far as Watana Canyon (just that one fish) telemetry data could not be used to
assess efficiency of the sonar systems.
An important issue that contributed uncertainty regarding whether some targets were of
sufficient size to classify them as Chinook Salmon involved fish that passed extremely close to
the sonar units. Some fish either moved through the blanking range (within 0.7 m [2.3 ft] of the
units), or through the most narrow part of the sample volume in the near -field. It was not
possible to measure these fish. Of 1,366 total observations, 100 (7.3 percent) could not be
measured for length. As a result, it is technically possible that some Chinook Salmon may have
passed by undetected. Given that 2.5 percent of the observations where a length was determined
were classified as Chinook Salmon, it is reasonable to estimate that 3 of 100 observations
without a length were Chinook Salmon.
7. CONCLUSIONS
The results of the sonar sampling in 2014 led to the following conclusions:
A net total of 24 upstream-migrant Chinook Salmon were counted, and this should be
considered a minimum estimate of Chinook Salmon abundance in the Watana Canyon;
Daily passage through the canyon was low, ranging from 0 to 3 fish per day;
There were no apparent diel passage patterns;
The distribution of passage was highly skewed towards the right bank; and
Distributions of fish detections as a function of distance from the sonar units indicate that
passage was shore-oriented.
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Table G-1. Location details for Watana Canyon sonar sites near PRM 187.1 in 2014.
Table G-2. Operating frequencies and data collection parameters used for the ARIS monitoring stations at
Watana Canyon in 2014.
Left Bank Right Bank
Operating Frequency (MHz) 0.7 1.1
Sample Window Start (m) 0.7 (2.3 ft) 0.7 (2.3 ft)
Sample Window End (m) 39.2 (128.6 ft) 16.6 (54.5 ft)
Sample Rate (frames per second) 5.4 6.8
Sonar Heading (degrees) 329 140
Sonar Tilt Angle (degrees) -9.6 -15.1
Sonar Roll Angle (degrees) 1.7 0.5
Table G-3. Percent coverage for each sonar station and combined based on wetted channel width, wetted
edge to sonar, and ensonified range at sample sites near PRM 187.1 in Watana Canyon.
Install
Date
ARIS
Unit
Sonar
Location Latitude Longitude Wetted Channel
Width (m)
Wetted Edge
to Sonar (m)
06-Jul 1200 River Left 62.82214 -148.5381 96 (315 ft)1.5 (4.9 ft)
07-Jul 1800 River Right 62.82307 -148.5370 106.1 (348 ft)3 (9.8 ft)
Combined
Sonar
Location
Wetted
Channel
Width (m)
Wetted Edge
to Sonar (m)
Ensonified
Range (m)Coverage %
River Left 96 (315 ft)1.5 (4.9 ft)39.2 (128.6 ft)41.5
River Right 106.1 (348 ft)3 (9.8 ft)16.6 (54.5 ft)16.1
Combined 57.6
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Table G-4. Sample effort, CPUE, and net upstream count of fish measuring 50 cm or greater at two ARIS units located at PRM 187.1 in the Upper
River, 2014. Mean daily discharge of the Susitna River at Tsusena Creek is also shown.
Table G-4. Continued.
Date Upstream
Down-
stream
Net
Upstream
Sample
Effort (h)
CPUE
(fish/h)Upstream
Down-
stream
Net
Upstream
Sample
Effort (h)
CPUE
(fish/h)
06-Jul 0 0 0 7.1 0.00 23,648
07-Jul 0 0 0 24.0 0.00 0 0 0 11.8 0.00 31,521
08-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 35,331
09-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 29,431
10-Jul 0 0 0 24.0 0.00 1 0 1 24.0 0.04 28,232
11-Jul 0 0 0 24.0 0.00 0 0 0 23.7 0.00 27,668
12-Jul 0 0 0 24.0 0.00 0 1 -1 24.0 -0.04 30,000
13-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 31,527
14-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 31,069
15-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 25,300
16-Jul 0 0 0 24.0 0.00 2 0 2 24.0 0.08 21,900
17-Jul 0 0 0 24.0 0.00 1 0 1 24.0 0.04 19,900
18-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 18,700
19-Jul 0 0 0 24.0 0.00 1 1 0 24.0 0.00 18,500
20-Jul 0 0 0 24.0 0.00 1 0 1 24.0 0.04 21,100
21-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 23,400
22-Jul 0 0 0 24.0 0.00 1 0 1 24.0 0.04 20,400
23-Jul 0 0 0 24.0 0.00 1 0 1 24.0 0.04 17,800
24-Jul 0 0 0 24.0 0.00 1 0 1 24.0 0.04 17,800
25-Jul 1 0 1 24.0 0.04 1 0 1 24.0 0.04 17,600
26-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 20,000
27-Jul 0 0 0 24.0 0.00 1 0 1 24.0 0.04 18,600
28-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 16,500
29-Jul 0 0 0 24.0 0.00 0 0 0 24.0 0.00 16,100
30-Jul 0 0 0 10.7 0.00 0 0 0 24.0 0.00 15,500
Mean
Discharge
(cfs)
River RightRiver Left
Fish Count Fish Count
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Date Upstream
Down-
stream
Net
Upstream
Sample
Effort (h)
CPUE
(fish/h)Upstream
Down-
stream
Net
Upstream
Sample
Effort (h)
CPUE
(fish/h)
31-Jul 2 0 2 24.0 0.08 15,600
01-Aug 3 0 3 24.0 0.13 15,700
02-Aug 2 0 2 24.0 0.08 15,900
03-Aug 1 0 1 24.0 0.04 16,200
04-Aug 0 0 0 24.0 0.00 16,200
05-Aug 1 0 1 24.0 0.04 16,600
06-Aug 1 0 1 24.0 0.04 17,300
07-Aug 0 0 0 10.3 0.00 0 0 0 23.9 0.00 16,200
08-Aug 0 0 0 24.0 0.00 1 0 1 24.0 0.04 15,600
09-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 15,700
10-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 14,800
11-Aug 0 0 0 23.7 0.00 0 0 0 24.0 0.00 14,200
12-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 14,700
13-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 14,800
14-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 14,500
15-Aug 0 0 0 24.0 0.00 1 0 1 24.0 0.04 14,700
16-Aug 1 0 1 24.0 0.04 0 0 0 24.0 0.00 16,400
17-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 17,300
18-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 18,000
19-Aug 0 0 0 23.8 0.00 0 0 0 24.0 0.00 17,700
20-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 16,200
21-Aug 0 0 0 24.0 0.00 0 0 0 24.0 0.00 15,400
22-Aug 0 0 0 10.1 0.00 1 0 1 12.0 0.08 14,700
Total 2 0 2 891.5 24 2 22 1067.2
River left sonar not operational
Mean
Discharge
(cfs)
River RightRiver Left
Fish Count Fish Count
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Table G-5. Discharge estimates based on spatial integration of velocity data for ADCP surveys conducted in the Watana Canyon in August, 2014.
Transect Start
Edge
Start
Time
Duration Width
(ft)
Area
(ft2)
Mean
Speed
(ft/s)
Left Q
(cfs)
Right Q
(cfs)
Total Q
(cfs)
Percent
Measured
T7 Right
Bank 14:08 0:02:25 344.1 2176 6.9 -0.8 -1.7 14,993 74.7
T7 Left
Bank 14:19 0:04:06 329.5 2069 7.2 -4.7 2.6 14,980 74.9
T6 Right
Bank 14:39 0:03:09 324.7 2265 6.6 8.7 0.8 15,058 73.6
T6 Left
Bank 14:59 0:04:07 320.2 2200 6.8 8.3 0.6 14,988 73.9
T5 Right
Bank 15:19 0:03:27 299.9 2132 6.7 3.8 0.9 14,601 74.3
T5 Left
Bank 15:23 0:03:18 306.0 2179 6.7 5.4 0.9 14,913 74.5
T4 Right
Bank 16:16 0:03:27 327.8 2347 6.3 0.4 1.0 15,267 74.8
T4 Left
Bank 16:31 0:03:06 327.4 2338 6.4 2.4 -3.1 15,125 75.3
T3 Left
Bank 16:42 0:02:39 305.4 2418 6.0 5.8 -2.9 14,698 75.8
T3 Right
Bank 16:46 0:03:12 309.2 2465 6.0 3.2 24.3 15,102 75.7
T2 Right
Bank 17:00 0:02:40 273.4 2401 6.1 3.9 23.5 15,030 76.4
T2 Left
Bank 17:03 0:02:43 265.8 2496 5.9 3.1 25.9 14,895 76.2
T1 Left
Bank 17:11 0:02:36 282.7 2414 6.2 6.2 1.2 14,890 76.3
T1 Right
Bank 17:20 0:02:30 276.7 2359 6.1 4.7 1.5 14,346 74.5
Mean 0:03:06 306.6 2304 6.4 3.6 5.4 14,920 75.1
Std Dev 0:00:32 23.3 129 0.4 3.4 10.2 227 0.9
COV 0.076 0.056 0.063 0.95 1.9 0.015 0.011
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Table G-6. Daily data collection parameters at the Watana Canyon sonar sites, 2014.
Date
Time
(hh:mm)
Sample
Location
Range
Start (m)
Range End
(m)
Sonar
Heading
(deg.)
Sonar Tilt
Angle
(deg.) Crew
6 Jul 16:51 River Left 2.9 39.2 329 -9.6 PJohnson, KShippen,
SBurril
7 Jul 12:11 River Right 0.7 16.6 50 -17.0 KShippen, PJohnson 14:52 River Left 0.7 39.1 330 -9.5
8 Jul 11:53 River Right 0.7 16.5 50 -17.0 KShippen, PJohnson 11:38 River Left 0.7 39.1 327 -10.0
9 Jul 08:40 River Right 0.7 16.5 49 -17.1 KShippen, SBurril 08:12 River Left 0.7 39.1 327 -9.7
10 Jul 08:53 River Right 0.7 16.5 50 -17.1 KShippen, SBurril 08:36 River Left 0.7 39.1 327 -9.9
11 Jul 09:34 River Right 0.7 16.5 47 -15.5 KShippen, SBurril 08:59 River Left 0.7 38.9 327 -9.8
12 Jul 08:22 River Right 0.7 16.5 47 -15.4 KShippen, JBures 08:42 River Left 0.7 38.9 326 -9.8
13 Jul 11:45 River Right 0.7 16.5 47 -16.5 KShippen, JBures 11:26 River Left 0.7 38.9 327 -9.8
14 Jul 08:28 River Right 0.7 16.5 48 -15.3 KShippen, JBures 09:09 River Left 0.7 38.9 324 -13.2
15 Jul 12:32 River Right 0.7 16.5 48 -15.4 KShippen, JBures 08:35 River Left 0.7 38.9 325 -13.2
16 Jul 09:23 River Right 0.7 16.5 50 -16.3 KShippen, JBures 08:44 River Left 0.7 38.9 324 -13.2
17 Jul 09:41 River Right 0.7 16.5 48 -15.2 KShippen, JBures 10:23 River Left 0.7 38.9 322 -12.6
18 Jul 11:55 River Right 0.7 16.5 47 -15.1 JBures, LGasek 12:26 River Left 0.7 39.1 318 -11.6
19 Jul 8:48 River Right 0.7 16.5 47 -15.2 JBures, LGasek 09:02 River Left 0.7 39.1 318 -11.6
20 Jul 8:48 River Right 0.7 16.5 47 -15.1 JBures, LGasek 09:10 River Left 0.7 39.0 318 -11.6
21 Jul 09:00 River Right 0.7 16.5 47 -15.6 JBures, LGasek 08:39 River Left 0.7 38.9 317 -11.5
22 Jul 12:03 River Right 0.7 16.5 56 -15.7 JBures, LGasek 12:22 River Left 0.7 39.0 318 -11.4
23 Jul 08:46 River Right 0.7 16.6 55 -14.9 JBures, LGasek 09:05 River Left 0.7 39.1 317 -11.5
24 Jul 09:53 River Right 0.7 16.5 54 -14.2 JBures, LGasek 09:38 River Left 0.7 39.0 317 -11.5
25 Jul 08:50 River Right 0.7 16.5 53 -14.2 JBures, LGasek 09:00 River Left 0.7 39.0 317 -11.5
26 Jul 08:51 River Right 0.7 16.5 53 -14.2 JBures, LGasek 09:07 River Left 0.7 38.8 317 -11.5
27 Jul 08:40 River Right 0.7 16.5 53 -14.2 JBures, LGasek 08:51 River Left 0.7 38.9 317 -11.5
28 Jul 10:15 River Right 0.7 16.5 53 -13.9 JBures, LGasek 10:55 River Left 0.7 39.0 334 -9.1
29 Jul 11:00 River Right 0.7 16.5 53 -14.1 JBures, LGasek 11:21 River Left 0.7 39.0 336 -9.2
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Table G-6. Continued.
Date
Time
(hh:mm)
Sample
Location
Range
Start (m)
Range End
(m)
Sonar
Heading
(deg.)
Sonar Tilt
Angle
(deg.) Crew
30 Jul 13:20 River Right 0.7 16.5 54 -14.0 JBures, LGasek 10:43 River Left 0.7 39.0 336 -9.1
31 Jul 09:28 River Right 0.7 16.6 54 -14.3 JBures, LGasek
1 Aug 09:24 River Right 0.7 16.6 54 -14.2 JBures, LGasek
2 Aug 08:46 River Right 0.7 16.5 54 -14.2 JBerry, LFerreira
3 Aug 09:36 River Right 0.7 16.5 54 -14.1 JBerry, LFerreira
4 Aug 09:56 River Right 0.7 16.5 54 -14.2 JBerry, LFerreira
5 Aug 09:37 River Right 0.7 16.5 54 -14.2 JBerry, LFerreira
6 Aug 11:33 River Right 0.7 16.5 53 -14.1 JBerry, LFerreira
7 Aug 09:56 River Right 0.7 16.5 54 -14.2 JBerry, LFerreira 13:47 River Left 0.7 39.5 327 -8.4
8 Aug 08:23 River Right 0.7 16.5 54 -14.2 JBerry, LFerreira 08:53 River Left 0.7 39.5 329 -8.3
9 Aug 08:40 River Right 0.7 16.5 54 -14.1 JBerry, LFerreira 08:29 River Left 0.7 39.5 329 -8.4
10 Aug 08:27 River Right 0.7 16.5 54 -14.2 JBerry, LFerreira 08:16 River Left 0.7 39.5 330 -8.3
11 Aug 08:13 River Right 0.7 16.6 54 -14.1 JBerry, LFerreira 08:30 River Left 0.7 39.5 330 -10.0
12 Aug 08:31 River Right 0.7 16.6 52 -13.0 JBerry, LFerreira 08:12 River Left 0.7 39.5 330 -10.0
13 Aug 08:26 River Right 0.7 16.6 52 -13.0 JBerry, LFerreira 08:14 River Left 0.7 39.5 329 -10.0
14 Aug 08:26 River Right 0.7 16.5 52 -13.0 JBerry, LFerreira 08:15 River Left 0.7 39.5 330 -10.0
15 Aug 08:19 River Right 0.7 16.5 52 -13.0 JBerry, NCollin 08:37 River Left 0.7 39.6 330 -10.0
16 Aug 11:07 River Right 0.7 16.5 52 -13.0 JBerry, NCollin 10:55 River Left 0.7 39.5 330 -10.2
17 Aug 08:21 River Right 0.7 16.4 51 -13.1 JBerry, NCollin 08:39 River Left 0.7 39.6 330 -10.1
18 Aug 08:30 River Right 0.7 16.4 51 -13.1 JBerry, NCollin 09:12 River Left 0.7 39.5 330 -10.1
19 Aug 08:10 River Right 0.7 16.5 46 -10.2 JBerry, NCollin 08:35 River Left 0.7 38.8 331 -8.4
20 Aug 09:04 River Right 0.7 16.5 50 -11.8 JBerry, NCollin 08:46 River Left 0.7 39.0 332 -8.4
21 Aug 08:03 River Right 0.7 16.5 56 -14.1 JBerry, NCollin 08:20 River Left 0.7 39.0 332 -8.4
22 Aug 08:39 River Right 0.7 16.5 55 -14.0 JBerry, NCollin 09:00 River Left 0.7 39.0 332 -8.4
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Figure G-1. Photograph of the Susitna River immediately downstream of the proposed Watana Dam Site
(PRM 187.1) showing the location of the river left and river right sonar sites and the wetted channel width.
Figure G-2. Photographs showing the ARIS mounts deployed at the left bank (left) and right bank (right)
monitoring stations.
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Figure G-3. Photographs showing the environmental boxes used to house the ARIS systems electronic
components, and power sources (battery banks are inside action packers) for the left bank (left) and right
bank (right) monitoring stations.
Figure G-4. Still images from ARIS data showing the cobble substrate (light-colored structure) along the left
bank (left) and right bank (right) fields-of-view. Substrate is visible to 38 and 16 m in range from the left and
right bank FOVs, respectively. Note range markers are shown in 2-m increments on left and 1-m increments
on right.
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Figure G-5. Ortho image showing the ensonified wetted width coverage of each ARIS unit near the Watana
Dam Site, 2014. Ensonified coverage is scaled to match the width of the river. River flow is from right to left.
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Figure G-6. Screen shots of Right Bank ARIS data showing echograms (left) and still sonar imagery (right)
for a resident fish (top) and Chinook Salmon (bottom). Echogram tracks are shown inside the black
rectangles and the fish targets in the imagery data are shown inside the white circles.
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Date (m/d)
Figure G-7. Daily sampling effort at two ARIS sonar units located at PRM 187.1 in the Upper River, 2014.
0
4
8
12
16
20
24
7/67/87/107/127/147/167/187/207/227/247/267/287/308/18/38/58/78/98/118/138/158/178/198/218/23Left Bank
(PRM 187.08)
0
4
8
12
16
20
24
7/67/87/107/127/147/167/187/207/227/247/267/287/308/18/38/58/78/98/118/138/158/178/198/218/23Right Bank
(PRM 187.12)Sampling Effort (hr)
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Figure G-8. Bathymetry profiles derived from ADCP data for transects aligned with ARIS sampling locations (PRM 187.1). Typical cross-sectional
coverage of ARIS sample areas are depicted with the overlaid triangles.
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Figure G-9. Net upstream count of fish measuring 50 cm or greater at two ARIS sonar units located at PRM
187.1 in the Upper River, 2014. Discharge of the Susitna River at Tsusena Creek is also shown.
Hour of the Day
Figure G-10. Diel migration of fish measuring 50 cm or greater counted at two ARIS sonar units located at
PRM 187.1 in the Upper River. Only upstream-moving fish are shown.
10,000
14,000
18,000
22,000
26,000
30,000
34,000
38,000
0
1
2
3
4
5
7/67/87/107/127/147/167/187/207/227/247/267/287/308/18/38/58/78/98/118/138/158/178/198/218/23Discharge (cfs)Net Upstream Fish CountDate (m/d)
River Left
River Right
Discharge
0
1
2
3
4
5
01234567891011121314151617181920212223River Left
0
1
2
3
4
01234567891011121314151617181920212223River Right
Number of Fish Counted
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Figure G-11. Percent of fish measuring 50 cm or greater counted at two ARIS sonar units located at PRM
187.1 in the Upper River as a function of distance from the sonar units, 2014. The mid-range distance was
calculated as the average of where a fish was first and last detected in the FOV. Only upstream-moving fish
are shown.
Figure G-12. Series of velocity profiles collected along transects using an ADCP at Watana Canyon (PRM
187.1) in 2014. Transects are arranged from upstream (top) to downstream (bottom) to allow for best
presentation of the transect-to-transect channel morphology. Range of sonar stations is shown for the River
Left site at Transect 3 and River Right site at Transect 6.
0
10
20
30
40
50
60
70
0 1 2 3 4 5 6 7 8 9 10
Distance from Sonar Units (m)
River Left
River Right
Percent of Fish
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Figure G-13. Individual velocity profile for Transect 3 in Watana Canyon (PRM 187.1) collected with an ADCP in 2014. This profile corresponds to
the location of the sonar station on River Left (ensonified zone illustrated).
Figure G-14. Individual velocity profile for Transect 6 in Watana Canyon (PRM 187.1) collected with an ADCP in 2014. This profile corresponds to
the location of the sonar station on River Right (ensonified zone illustrated).
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Figure G-15. Bathymetry in Watana Canyon (PRM 187.1) based on seven serial ADCP transects, 2014.
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Appendix H: Indian River Escapement Estimate for chinook salmon
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1. INDIAN RIVER ESCAPEMENT ESTIMATE
Two components are required to estimate abundance using AUC methods: 1) an estimate of the
number of fish-days derived from an area under the escapement curve; and 2) an estimate of the
residence time, or the length of time that fish are alive in the survey area. For this study, the
escapement curve was derived from Chinook Salmon counts made during aerial spawner
surveys, and residence time was estimated from detections of radio-tagged Chinook Salmon
made during aerial telemetry surveys in the Indian River.
Aerial spawner surveys were conducted in the Indian River every third day from early July to
late August to count the number of live Chinook Salmon present in the river. Aerial spawner
counts were stratified into three river sections. Section 1 extended from the clear -water plume at
the confluence with the Susitna River up to Bridge 1 in the lower Indian River; Section 2 ranged
from Bridge 1 to the power-line crossing; and Section 3 ranged from the power-line crossing to
the Forks. Due to the resolution available from radio telemetry, the study team could not
definitively assign radio-tagged Chinook Salmon detected in proximity to the confluence (below
Bridge 1) to either Section 1 or the turbid waters of the mainstem Susitna River. To estimate
residence time (and mark rates), it was important that the aerial spawner counts and radio-tag
detections correspond to the same survey areas, thus all subsequent AUC calculations were
germane to the area upstream of Bridge 1 (i.e., only data from river sections 2 and 3 were used).
For each river section, crews recorded their observed counts and an estimate of observer
efficiency. As part of the AUC calculations described below, the estimates of observer
efficiency were used to ‘adjust’ the observed counts. Observer efficiency was estimated for each
river section because there were differences in the physical characteristics of each (e.g., gradient,
substrate, flow dynamics, vegetation cover); and these differences can influence an observer’s
ability to count fish. Environmental conditions used to estimate observer efficiency included
water clarity, sun glare, and vegetation cover, all of which were ranked on a scale of 0 to 4 (0 is
poor, 4 is optimal). Survey crews also took weather conditions and professional judgment into
account when estimating observer efficiency for each river section.
Aerial telemetry surveys were also conducted in the Indian River every third day from early July
to late August, on the same days as the aerial spawner surveys. Aerial telemetry surveys were
used to count the number of radio-tagged Chinook Salmon in each of the river sections, and to
record whether the radio-tagged fish were alive or dead.
As described by English et al. (1992), the number of live fish present in the study area on the ith
day (pi) was estimated by:
𝑛�ℎ=∑𝑒𝑛𝐿�=1 ∙𝑁�∙𝑛𝑟�ℎ�−1 ∙𝑛𝑒�ℎ�−1 (1)
where: L is the number of spatial strata (h) within each stream; foih is the fish observed during
surveys in stratum h on the ith sampling day; nh is the number of sampling units in stratum h; nsih
is the number of units surveyed in stratum h on the ith sampling day; and oeih is the observer
efficiency.
The area under the escapement curve (auc) was estimated by:
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𝑎𝑟𝑐=0.5 ∙∑(𝑟�ℎ−𝑟�ℎ)∙(𝑛�ℎ+𝑛�ℎ−1 )𝑛
�ℎ=2 (2)
where: ti is the number of days measured from the first day fish enter the survey area to the ith
sampling day; and n-2 is the number of surveys when fish were seen.
An escapement estimate (N) was then calculated as:
𝑁= 𝑎𝑟𝑐𝑟𝑟⁄ (3)
Residence time (rt) of Chinook Salmon in the Indian River was estimated using radio-tagged fish
that were released in the Lower and Middle rivers. All radio tags were equipped with a mortality
sensor that changed the signal pattern to an “inactive” mode for the remainder of the season once
the tag became stationary for 24 hours. Residence times for individual fish were calculated as
the cumulative length of time spent alive in the study area. Aerial telemetry surveys were not
flown daily, so the dates that some fish died were approximated. Median residence times were
used in AUC calculations.
Escapement estimates derived using AUC methods are dependent on the input values for
observer efficiency and residence time. Despite using consistent aerial surveying methods with
an experienced crew, and having access to telemetry data from dozens of radio-tagged fish in the
Indian River, the estimates of these parameters were potentially biased to some degree in 2014.
Validation was compromised by the Indian River weir being rendered inoperable prior to the
onset of the Chinook Salmon run, so there were no weir counts available to ‘ground-truth’ the
aerial spawner surveys. As such, the study team conducted a sensitivity analysis to determine
the potential impact of reducing estimates of observer efficiency on the escapement estimate.
2. MARK RATE
The mark rate, or the proportion of the Chinook Salmon run that was tagged, was estimated for
the Middle River fishwheels by dividing the total number of large, radio-tagged Chinook Salmon
released in the Middle River that were detected above Bridge 1 by the estimated escapement of
fish above Bridge 1.
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Table H-1. Number of Chinook Salmon counted during aerial spawner surveys in the Indian River, and the
number of radio-tagged large Chinook Salmon detected, by tag site, 2014. These data are preliminary, and
additional aerial spawner surveys are planned for August (these data will be added to the table later).
Survey
Date
River
Section a
Observer
Efficiency Observed Adjusted
Middle
River
Lower
River
Middle
River
Lower
River Comment
07-Jul 1 60%36 60 x x Good conditions
2 70%91 130 17 2 Most fish holding in pools
3 80%0 0 1 0 pool count estimated
Total 127 190 13.8%1.5%
10-Jul 1 50%82 164 x x Fair conditions
2 60%184 307 20 2 dark, light rain
3 70%29 41 3 1 Most fish holding in pools
Total 295 512 6.6%0.9%pool count estimated
14-Jul 1 60%123 205 x x Good conditions
2 70%233 333 48 3 Some fish holding in pools
3 80%72 90 10 2 pool count estimated
Total 428 628 13.7%1.2%
17-Jul 1 60%110 183 x x Good conditions
2 70%389 556 67 5 Less fish in pools
3 80%101 126 15 4 Spawning activity
Total 600 865 12.0%1.3%
19-Jul 1 40%61 153 x x Poor conditions
2 50%330 660 68 3 Bad weather
3 60%56 93 20 5 dark and rainy
Total 447 906 11.7%1.1%
22-Jul 1 60%160 267 x x Excellent conditions
2 70%490 700 77 5 Fish evenly distributed
3 80%148 185 28 3 on spawning grounds
Total 798 1,152 11.9%0.9%
26-Jul 1 50%70 140 x x Fair conditions
2 60%327 545 85 6 Turbidity in lower reaches
3 80%108 135 30 5 following high water event
Total 505 820 16.9%1.6%
29-Jul 1 60%67 112 x x Excellent conditions
2 70%379 541 83 4 Fish redistributed
3 80%160 200 26 5 following high water event
Total 606 853 14.7%1.2%
01 Aug b 1 60%47 78 x x Good conditions
2 70%351 501 82 6 Corresponding aerial
3 80%146 183 22 3 telemetry survey was
Total 544 762 15.2%1.3%conducted on July 31
Live Tags Detected c Mark Ratec
(by Tag Site)(by Tag Site)Aerial Count
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Table H-1. Continued.
Survey
Date
River
Section a
Observer
Efficiency Observed Adjusted
Middle
River
Lower
River
Middle
River
Lower
River Comment
03-Aug 1 60%59 98 x x Good conditions
2 70%323 461 47 4
3 80%96 120 16 5
Total 478 680 10.8%1.5%
06-Aug 1 60%34 57 x x Good conditions
2 70%214 306 38 4
3 80%58 73 11 4
Total 306 435 13.0%2.1%
09-Aug 1 60%18 30 x x Good conditions
2 70%127 181 32 3
3 80%24 30 7 3
Total 169 241 18.4%2.8%
12-Aug 1 60%6 10 x x Good conditions
2 70%55 79 22 2
3 80%14 18 3 2
Total 75 106 26.0%4.2%
15-Aug 1 60%5 8 x x Good conditions
2 70%16 23 13 2
3 80%4 5 3 2
Total 25 36 57.4%14.4%
18-Aug 1 60%0 0 x x Good conditions
2 70%2 3 4 3
3 80%1 1 3 3
Total 3 4 170.4%146.1%
19-Aug 1 60%0 0 Good conditions
2 70%2 3
3 80%1 1
Total 3 4
a Section 1 = clearwater plume to Bridge 1; Section 2 = Bridge 1 to Powerline; Section 3 = Powerline to Forks.
b The aerial telemetry survey corresponding to the August 1 aerial spawner survey was conducted on July 31.
c Counts of live tags (and mark rate calculations) were based on data collected in sections 2 and 3 and excluded section 1.
No aerial telemetry
survey was flown on
8/19
Live Tags Detected c Mark Ratec
(by Tag Site)(by Tag Site)Aerial Count
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Table H-2. Summary of AUC abundance estimate, mark rate at the Middle River tag site, and the expected
number of fish passed the Watana Dam sonar site, 2014.
Figure H-1. Number of Chinook Salmon counted during aerial spawner surveys above Bridge 1 in the Indian
River, 2014. Observed counts (dashed red line) for each survey were expanded by reach-specific estimates of
observer efficiency to derive ‘adjusted’ counts (solid blue line). The zero count on June 25 was estimated; no
Chinook Salmon were observed passing the Indian River weir through June 25 (prior to it being washed out
by a high-water event). The zero count on August 20 was estimated (surveyors indicated that the three
remaining live Chinook Salmon observed on August 19 were moribund).
Area under the escapement curve (fish days)20,280
Median residence time (days)15.6
Estimated abundance of large Chinook salmon above Bridge 1 1,297
Number of Middle River tags above Bridge 1 171
Mark rate at Middle River fishwheels (%)13.2
One of every 'X' fish was tagged in Middle River, where 'X' =7.6
Expected number of fish passed Watana given that one tag passed =7.6
Expected number tags passed Watana given sonar count of 24 fish =3.2
0
150
300
450
600
750
900
6/256/276/297/17/37/57/77/97/117/137/157/177/197/217/237/257/277/297/318/28/48/68/88/108/128/148/168/188/20Number of FishDate (m/d)
Observed Adjusted
No fish
counted
at weir as
of 6/25
First aerial
spawner
survey on 7/7
Assumed
no live
fish left
by 8/20
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Figure H-2. Relative frequency of residence times (days) for radio-tagged Chinook Salmon above Bridge 1 in
the Indian River, 2014.
0%
5%
10%
15%
20%
25%0-55-1010-1515-2020-2525-3030-3535-4040-4545-5050-5555-6060-65Relative FrequencyResidence Time (d)
Chinook Salmon above Rail Bridge
in Indian River
(days to death or departure)
Median = 15.6 days
(n = 184)
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Appendix I: Estimate the system-wide Chinook Salmon escapement, Coho
Slamon escapement above the Yentna River, and the distribution of
those fish among tributaries of the susitna river
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1. INTRODUCTION
This appendix presents the data analyses pertinent to the estimation of Chinook and Coho salmon
abundance in the Susitna River upstream of the confluence with the Yentna River, and Chinook
Salmon abundance in the Yentna River drainage.
1.1. Study Objective
The Chinook and Coho salmon abundance and distribution estimates reported herein are a
component of the following study objective.
From Section 2, Objective 8:
8) Estimate the system-wide Chinook Salmon escapement to the entire Susitna River, the
Coho Salmon escapement to the Susitna River above the confluence with the Yentna
River, and the distribution of Chinook, Coho, and Pink salmon among tributaries of the
Susitna River (upstream of Yentna River confluence) in 2013 and 2014.
2. STUDY AREA
The section of the Susitna River upstream of the confluence with the Yentna River is hereafter
referred to as the “mainstem Susitna River” and encompasses the “Lower,” “Middle,” and
“Upper” sections of the Susitna River as defined in Section 3. For Yentna River Chinook
Salmon, the abundance and spawning distribution estimates are germane to the Chinook Salmon
population passing the marking sites on the lower Yentna River at river mile 6.
3. METHODS
See Section 4.8.
4. RESULTS
4.1. Estimated Abundance of Chinook Salmon
4.1.1. Mainstem Susitna River Above the Yentna River Confluence
A total of 2,048 Chinook Salmon of all sizes were captured in drift gillnets and two fishwheels at
the lower mainstem Susitna River tagging site (PRM 34) from May 22 to August 19, 2014.
Radio tags were deployed on 659 Chinook Salmon measuring 50 cm (19.7 in) METF or greater.
Based on observations made at fixed-station receiver sites and using aerial radio-telemetry, 494
of these radio-tagged fish moved upstream and remained one mile upstream of the east bank
fishwheel and therefore met criteria to be in the mark-recapture experiment. The remaining 165
(659–494) radio-tagged Chinook Salmon either migrated to the Yentna River drainage or the
Susitna River below PRM 34, failed to migrate due to handling stress, or were above the tagging
site and not detected (unlikely). It was also possible that some tags were regurgitated below the
point at which the tagged fish were categorized as being part of the mark-recapture experiment
(one mile upstream of the east bank fishwheel). Second event sampling was conducted at weirs
on the Deshka River and at Montana Creek. A total of 16,335 Chinook Salmon were counted
through the Deshka River weir from May 19 to September 2, 2014, with 13,908 of these fish
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estimated to be 50 cm (19.7 in) METF or greater. At the Montana Creek weir, 1,217 Chinook
Salmon were counted from June 23 to September 11, of which 1,212 fish were estimated to be
50 cm (19.7 in) METF or greater. Second event sampling was also conducted at a site on the
Chulitna River using telemetry and an ARIS sonar system. However, the sonar echogram
quality, counts, and length determinations suggest the data to be unreliable and they were not
used. The estimated numbers of Chinook Salmon measuring 50 cm (19.7 in) METF or greater
that passed the Deshka River and Montana Creek weirs comprised the second event of the mark -
recapture experiment.
Based on observations made at fixed-station receivers and using aerial radio-telemetry, 125
radio-tagged Chinook Salmon passed the Deshka River weir and were assumed to have spawned
above the weir. Similarly, 15 radio-tagged Chinook Salmon passed the Montana Creek weir and
were assumed to have spawned above the weir. Flood events at the Deshka weir on June 28–29
and at the Montana Creek weir on June 26–30 prevented accurate counting. Recaptures
associated with these periods were removed from the data (one tag was removed for each of the
Deshka River and Montana Creek datasets). The remaining 138 recaptures (125+15-2) were
used in the mark-recapture experiment.
Tests for size-biased sampling in the marking and recapture events were conducted using the KS
two-sample test (Cleary et al. 2013). The tests for the second sampling event, which compared
the length distributions of marked and recaptured fish, provided significant evidence of size
biased sampling (P = 0.016; Figure I-1).
The test for size-biased sampling during the first event using data from fish passing the Deshka
River weir provided significant evidence of size biased sampling (P < 0.001; Figure I-2). A
similar test for size-biased sampling during the first event using data from fish passing the
Montana Creek weir also provided evidence of size biased sampling (P = 0.026, Figure I-3),
although the length of the maximum D-value, and hence the suggested stratification point, was
considerably smaller. Given that the sample sizes at the Montana weir were substantially lower
than those at the Deshka River weir results of the first-event KS test using data from the Deshka
River weir were preferred. Montana Creek weir counts (of fish measuring 50 cm [19.7 in] or
greater) and recaptures were approximately 9 percent and 11 percent of those at the Deshka
River weir.
Based on these test results, the data were stratified into two size strata: 50.0–78.5 cm (19.7–30.9
in) METF, and 78.5 cm (30.9 in) METF or greater. Re-running the KS tests for size selectivity
within each size category failed to detect any selectivity at α = 0.05. Moreover, for each of the
size categories, one of the two KS tests described above was not significant at α = 0.2.
Tests for consistency of the Chapman (1951) model for estimation of abundance with respect to
temporal and/or spatial variation in probability of capture were conducted within the each of the
2 size strata. These tests were first described by Seber (1982; p. 438–439) and subsequently
described as the ‘Equal Proportions Test” (EP) and the “Complete Mixing Test” (CM) by
Arnason et al. (1996). A passing EP or CM test means the Chapman model is valid. The EP
tests examine the consistency of marked fractions in the second event sample over spatial and
temporal strata. The EP tests were only approximate, because the number of fish inspected for
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marks during second event sampling within each stratum was not known, but was estimated
using size composition data collected at each weir.
Before the EP tests were conducted an adjustment to the timing of the recaptures at the weirs was
made; this adjustment affected the EP tests on temporal strata. Analysis of the timing of weir
counts and recaptures at the Deshka weir strongly suggested a tag-induced lag for the recaptured
fish. The median run timing of the untagged fish was significantly earlier than that of the
recaptured fish (Mann-Whitney test; W = 764, 482; P < 0.001); the median difference was
estimated at 4 days (Figure I-4). Tag-induced delay in migration has been previously observed
in Chinook Salmon (Bendock and Alexandersdottir 1993; Bernard et al. 1999). The latter
authors found a lag of approximately 4–5 days before radio-tagged Chinook Salmon in the Kenai
River, Alaska, resumed upstream migration. Recoveries at the Montana Creek weir were too
sparse to show an effect. The run timing of the recaptures was adjusted at the Deshka and
Montana weirs by moving them 4 days earlier (note that the flood adjustment described earlier
was performed on the lag-adjusted data).
For the 50.0–78.5 cm (19.7–30.9 in) METF stratum, the EP test passed on the spatial (Test 3 in
Table I-1; P = 0.921) and temporal scales (Tests 4 and 5 in Table I-1; P = 0.09 and 0.189 for
Deshka and Montana, respectively). The CM test passed on a temporal scale (Test 2 in Table I-
1; P = 0.311), but not on a spatial scale (Test 1 in Table I-1; P < 0.001). These results indicate
that the Chapman model is appropriate for estimating abundance for the 50.0–78.5 cm (19.7–
30.9 in) METF stratum.
For the 78.5 cm (30.9 in) METF or greater stratum, the EP test passed on the temporal scale
(Tests 4 and 5 in Table I-2; P = 0.70 and 1 for Deshka and Montana, respectively); the EP test
did not pass on the spatial scale (Test 3 in Table I-2; P = 0.001). The CM test passed on the
spatial and temporal scale (Tests 1 and 2 in Table I-2; P = 0.187 and P = 0.148, respectively). It
is noted that the contingency tables used in Table I-2 are sparse, and the sample sizes border the
conditions at which the chi-square tests are not strictly valid. As given, however, these results
indicate that the Chapman model is appropriate for estimating abundance for the 50.0–78.5 cm
(19.7–30.9 in) METF stratum; moreover, no stratified design would be possible with the sparse
sample sizes in this category.
Abundance for each stratum was estimated using the Chapman (1951) model. The distribution
of mark-recapture estimates is recognized to be frequently asymmetric (e.g., Zwane and van der
Heijden 2003), thus the utility of analytically-estimated standard errors in calculating confidence
intervals is limited. Also, the analytical formula of variance of the Chapman estimate of
abundance assumes the number of fish examined in the second event for tags is a constant. In
this experiment length samples were used to estimate the number of fish measuring 50 cm (19.7
in) METF or greater inspected at the weirs for tags. Finally, estimating the number of fish
examined in each stratum creates dependency among the stratum-specific abundance estimates
because higher estimates of small fish necessarily means smaller estimates of larger fish and vice
versa. For these reasons, variances and confidence intervals were estimated using a parametric
bootstrap (e.g., Buckland and Garthwaite 1991).
Within each size stratum, the probability that a marked fish was recaptured was modeled as a
hypergeometric process with observed numbers of fish marked, estimated number inspected in
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the second event and estimated abundance as model parameters. For each of the two weir sites,
the numbers of fish inspected for marks was modeled as a multinomial process with total
observed passage at the weir and the empirical size distribution data collected at each weir used
to define model parameters. A 100,000 parametric bootstrap samples were generated. Variance
of the abundance estimate of fish of each size class was calculated as the sample variance of the
100,000 bootstrap estimates of each estimate. Variance of the abundance estimate of all fish
measuring 50 cm (19.7 in) METF or greater was calculated as the sample variance of the
100,000 bootstrap estimates of the sum of the abundance of the two size classes (Table I-3).
Confidence intervals reported in Table I-4 are percentiles of the parametric bootstrap
distributions of estimated parameters.
The abundance of Chinook Salmon measuring 50 cm (19.7 in) METF or greater spawning in the
Susitna River above the mainstem tagging site in 2014 is estimated to be 68,225 (SE = 10,615).
4.1.2. Yentna River
A total of 3,071 Chinook Salmon were captured in drift gillnets and two fishwheels at the Yentna
River tagging site (RM 6) from May 22 to August 25, 2014. Dart tags were deployed on 1,281
Chinook Salmon measuring 50 cm (19.7 in) METF or greater. Radio tags were also deployed on
296 of the dart-tagged fish. These radio-tagged fish were used to a) estimate the drop-out rate of
the dart-tagged fish due to handling mortality and migration to the mainstem Susitna drainage,
and b) estimate spawning distribution in the Yentna drainage. Based on observations made at
fixed tracking stations and using aerial radio telemetry, 219 of the radio-tagged fish moved
upstream and remained at least one mile upstream of the east bank fishwheel for at least 48 hours
and therefore met criteria to be used in the mark recapture study. The remaining 77 (296-219)
radio-tagged Chinook Salmon either migrated to the Susitna River drainage or the Susitna River
below the Yentna-mainstem Susitna confluence, failed to migrate due to handling stress, or
migrated above the tagging site and not detected (unlikely). The number of deployed dart tags
was deprecated based on the proportion of radio tags failing to enter the mark-recapture
experiment. Of the 1,281 dart tags deployed, it is estimated that 963 tags entered the mark-
recapture experiment. With respect to the spawning distribution study, 5 radio-tagged fish were
harvested and 7 made it to the recapture wheels but then died, leaving only 207 (219-12) radio-
tagged fish for inclusion in the distribution study.
Second event sampling was conducted using two fishwheels and a mid-river gillnet at RM 18. A
total of 2,308 Chinook Salmon were caught in the second event sampling from May 24 to
August 22, 2014, with 1,371 of these fish measuring 50 cm (19.7 in) METF or greater. Second
event sampling recovered 59 dart tags, 25 on the west fishwheel, 31 on the east fishwheel, and 3
in the gillnet. Ten of the 59 recovered dart tagged fish were also radio tagged.
Tests for size-biased sampling in the marking and recapture events were conducted using the KS
two-sample test (Appendix A1 in Cleary et al. 2013). The test for the second sampling event,
which compared the length distributions of marked and recaptured fish, provided no evidence of
size biased sampling (P = 0.65, D = 0.088; Figure I-5).
The tests for size-biased sampling during the first event using data from fish passing the
fishwheels and gillnet at RM 6 provided no significant evidence of size biased sampling
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(P = 0.12, D = 0.196 for the east fishwheel, P = 0.67, D = 0.131 for the west fishwheel and P =
0.97, D = 0.053 for pooled fishwheel and gillnet data; Figures I-6, I-7, and I-8). No test was
performed for the second event gillnet-only data as there were too few recaptures (3). Based on
these test results, the data were pooled into one size class (all fish ≥ 50 cm [19.7 in] METF).
Tests for consistency of the Chapman (1951) model for estimation of abundance with respect to
temporal and/or spatial variation in probability of capture were conducted. These tests were first
described by Seber (1982, p. 438–439) and subsequently described as the ‘Equal Proportions
Test” (EP) and the “Complete Mixing Test” (CM) by Arnason et al. (1996). A passing EP or
CM test means the Chapman model is valid. The EP tests examine the consistency of marked
fractions in the second event sample over spatial and temporal strata. Before the EP tests were
conducted an adjustment to the timing of the recaptures at the second event capture site was
made; this adjustment affected the EP tests on temporal strata. Analysis of the timing of
fishwheel catches (≥ 50 cm [19.7 in] METF) and recaptures at the recapture wheels strongly
suggested a tag-induced lag for the recaptured fish. The median run timing of the untagged fish
was significantly earlier than that of the recaptured fish (Mann-Whitney test, W = 46,870,
P = 0.019); the median difference was estimated at 3 days (Figure I-9). Tag-induced delay in
migration has been previously observed in Chinook Salmon (Bendock and Alexandersdottir
1993; Bernard et al. 1999). The latter authors found a lag of approximately 4–5 days before
radio-tagged Chinook Salmon in the Kenai River, Alaska, resumed upstream migration.
Moreover, a tag-induced lag of 4 days was also detected for radio-tagged fish in the mainstem
Susitna mark recapture component of this study in 2014. The run timing of the recaptures in the
current study was adjusted at the second event fishwheels by moving the recapture date 3 days
earlier.
The EP test passed on the spatial (Test 3 in Table I-5; P = 0.58) and temporal scales (Tests 4-6 in
Table I-5; P = 0.83, P = 0.55 and P = 0.44 for the east fishwheel, west fishwheel and pooled
gear, respectively). The CM test passed on the spatial scale (Test 1 in Table I-5; P = 0.68) and
on the temporal scale (Test 2 in Table I-5; P = 0.35). These results indicate that the Chapman
model is appropriate for estimating abundance for the Chinook Salmon measuring 50 cm (19.7
in) METF or greater on the Yentna River.
The distribution of mark recapture estimates is recognized to be frequently asymmetric (e.g.
Zwane and van der Heijden 2003), thus the utility of analytically-estimated standard errors in
calculating confidence intervals is limited. Also, the analytical formula of variance of the
Chapman estimate of abundance assumes the number of fish marked in the first event is a
constant. In this experiment, we used radio tag migration data to estimate the proportion of
marked fish that migrated into the mark-recapture experiment. For these reasons, variances and
confidence intervals were estimated using a parametric bootstrap (e.g., Buckland and Garthwaite
1991).
We note that we found variation in the downstream migration pattern of radio-tagged Chinook
Salmon among (two) different crews. Pooled over gear types, fish radio-tagged by one crew (A)
experienced a drop-out rate of about 33 percent, while the rate for the other crew was (B) was
about 12 percent. Consistently, the recapture rate of dart-tagged fish for crew A was about 2.8
percent, while for crew B it was 6.2 percent. The influence on tagged fish by crew B was not
therefore limited to the act of radio-tagging, and appears related to general handling of fish. It is
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also noted that timing of radio-tagging or type of gear appears not to explain the differences in
drop-out rate between crews. To accommodate these differences in the abundance analysis, we
applied crew-specific drop-out rates to marked fish.
For the simulation, the probability that a marked fish was recaptured was modeled as a
hypergeometric process with estimated number of fish marked, number inspected in the second
event, and estimated abundance as model parameters. For each of the two crews, the numbers
of fish exhibiting downstream migration was modeled as a binomial process with number of
radio tags deployed and the estimated drop-out rate used to define model parameters. A sample
of 50,000 parametric bootstrap realizations was generated. Variance of the abundance estimate
was calculated as the sample variance of the 50,000 bootstrap estimates of each estimate. The 95
percent confidence interval for the abundance estimate was calculated as the 2.5 and 97.5
percentiles of the parametric bootstrap distributions of the estimated abundance.
The abundance of Chinook Salmon measuring 50 cm (19.7 in) METF or greater spawning in the
Yentna River above the lower tagging site in 2014 is estimated to be 22,267 (SE = 2,871;
CV = 13 percent; Table I-6). The 95 percent parametric bootstrap confidence interval is 17,466
to 28,701.
4.2. Estimated Abundance of Coho Salmon
A total of 1,513 Coho Salmon were captured in two fishwheels at the lower mainstem Susitna
River tagging site (PRM 34) from June 28 to August 26, 2014. Radio tags were deployed on 640
Coho Salmon measuring 40 cm (15.7 in) METF or greater. Based on observations made at fixed
tracking stations and using aerial radio-telemetry, 582 of these radio-tagged fish moved upstream
and remained one mile upstream of the east bank fishwheel and therefore met criteria to be
included in the mark- recapture experiment. The remaining 58 (640-582) radio-tagged Coho
Salmon either migrated to the Yentna River drainage or the Susitna River below PRM 34, failed
to migrate due to handling stress, or were above the tagging site and not detected (unlikely). It is
also possible that some tags were regurgitated below the point at which the tagged fish were
categorized as being part of the mark-recapture experiment (one mile upstream of the east bank
fishwheel). Second event sampling was conducted at weirs on the Deshka River and at Montana
Creek. A total of 11,578 Coho Salmon were counted through the Deshka River weir from July 4
to September 2, 2014, with all of them estimated to be 40 cm (15.7 in) METF or greater. At the
Montana Creek weir 934 Coho Salmon were counted from August 3 to September 21; all were
estimated to be 40 cm (15.7 in) METF or greater. The estimated number of Coho Salmon
measuring 40 cm (15.7 in) METF or greater that passed the Deshka River and Montana Creek
weirs comprised the second event of the mark-recapture experiment.
Based on observations made at fixed tracking stations and using aerial radio-telemetry, 68 radio-
tagged Coho Salmon passed the Deshka River weir and were assumed to have spawned above
the weir. Similarly, 4 radio-tagged Coho Salmon passed the Montana Creek weir and were
assumed to have spawned above the weir. A total of 72 recaptures (68 + 4) were used in the
mark-recapture experiment.
Tests for size-biased sampling in the marking and recapture events were conducted using the KS
two-sample test (Appendix A1 in Cleary et al. 2013). The tests for the second sampling event,
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which compared the length distributions of marked and recaptured fish, provided significant
evidence of size biased sampling (P < 0.001; Figure I-10).
The test for size-biased sampling during the first event using data from fish passing the Deshka
River weir provided significant evidence of size biased sampling (P ≤ 0.001, Figure I-11). No
test for size-biased sampling during the first event was conducted using data from the Montana
Creek weir because only four fish were recaptured at that site.
Based on the test results of the above KS tests, the data were stratified into two size strata: 40–55
cm (15.7–21.7 in) METF, and 55 cm (21.7 in) METF or greater. Rerunning the KS tests for size
selectivity within each size category indicated that no further size stratification was needed.
Tests for consistency of the Chapman (1951) model for estimation of abundance with respect to
temporal and/or spatial variation in probability of capture were conducted within the each of the
2 size strata. These tests were first described by Seber (1982; hypotheses H2 and H4 on p. 438–
439) and were subsequently described as the “Complete Mixing Test” (CM; H2) and the ‘Equal
Proportions Test” (EP; H4) by Arnason et al. (1996). A passing EP or CM test indicates the
Chapman model is valid. The EP tests examine the consistency of marked fractions in the
second event sample over spatial and temporal strata. The EP tests were only approximate,
because the number of fish inspected for marks during second event sampling within each
stratum was not known, but was estimated using size composition data collected at each weir.
No adjustment to the timing of the recaptures at the weirs was made; we found no evidence of a
difference in the timing at the Deshka weir of tagged and untagged fish.
For the 40–55 cm (15.7–21.7 in) METF stratum, the EP test passed on the spatial (Test 3 in
Table I-7; P = 0.382) and temporal scales (Test 4 in Table I-7; P = 0.217 for the Deshka recovery
site). There were too few recoveries at Montana to conduct the test for this site. The CM test
passed on a temporal scale (Test 2 in Table I-7; P = 0.225), but not on a spatial scale (Test 1 in
Table I-7; P ≤ 0.001). These results indicate that the Chapman model is appropriate for
estimating abundance for the 40–55 cm (15.7–21.7 in) METF stratum.
For the 55 cm (21.7 in) METF or greater stratum, the EP test passed on the spatial scale (Test 3
in Table I-8; P ~ 1.0) and temporal scales (Test 4 in Table I-8; P = 0.13 for the Deshka recovery
site). There were too few recoveries at Montana to conduct the test for this site. The CM test
passed on the temporal scale (Test 2 in Table I-8; P = 0.113), but not the spatial scale (Test 1 in
Table I-8; P = 0.006). These results indicate that the Chapman model is appropriate for
estimating abundance for the 55 cm (21.7 in) METF or greater stratum.
Abundance for each stratum was estimated using the Chapman (1951) model. The distribution
of mark recapture estimates is recognized to be frequently asymmetric (e.g., Zwane and van der
Heijden 2003), thus the utility of analytically-estimated standard errors in calculating confidence
intervals is limited. Also, the analytical formula of variance of the Chapman estimate of
abundance assumes the number of fish examined in the second event for tags is a constant. In
this experiment length samples were used to estimate the number of fish within each size stratum
that were inspected at the weirs for tags. Finally, estimating the number of fish examined in each
stratum creates dependency among the stratum-specific abundance estimates because higher
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estimates of small fish necessarily means smaller estimates of larger fish and vice versa. For
these reasons, variances and confidence intervals were estimated using a parametric bootstrap
(e.g., Buckland and Garthwaite 1991).
Within each size stratum, the probability that a marked fish was recaptured was modeled as a
hypergeometric process with observed numbers of fish marked, estimated number inspected in
the second event and estimated abundance as model parameters. For each of the two weir sites,
the numbers of fish inspected for marks was modeled as a multinomial process with total
observed passage at the weir and the empirical size distribution data collected at each weir used
to define model parameters. A sample of 100,000 parametric bootstrap realizations was
generated. Variance of the abundance estimate of fish of each size class was calculated as the
sample variance of the 100,000 bootstrap estimates of each estimate. Variance of the abundance
estimate of all fish measuring 40 cm (15.7 in) METF or greater was calculated as the sample
variance of the 100,000 bootstrap estimates of the sum of the abundance of the two size classes
(Table I-9). Confidence intervals reported in Table I-4 are percentiles of the parametric
bootstrap distributions of estimated parameters.
The abundance of Coho Salmon measuring 40 cm (15.7 in) METF or greater spawning in the
Susitna River above the mainstem tagging site in 2014 is estimated to be 84,879 (SE = 9,550;
Table I-10).
4.3. Estimated Distribution of Spawning Salmon
4.3.1. Chinook Salmon
4.3.1.1. Mainstem Susitna River Above the Yentna River Confluence
Results from the mark–recapture experiment indicate that radio tags were not deployed in
Chinook Salmon proportional to the size distribution of fish in the population. To estimate
abundance of spawning salmon in different tributaries within the mainstem Susitna River
drainage, the number of spawners among tributaries was first estimated within each size stratum.
Numbers of fish by tributary within a size stratum was then calculated as the product of the
proportion by tributary within size stratum and estimated abundance for that size stratum (Table
I-3). Numbers of fish were then summed over size strata for each tributary.
4.3.1.2. Yentna River
No size selectivity was found for the marked fish in the mark-recapture analysis described above.
We also found no significant difference between the size distributions of the radio-tagged fish
and the marked fish used in the mark-recapture analysis (D = 0.084, P = 0.1); we assume
therefore there to be no size selectivity among the radio-tagged fish. Recoveries of radio tags in
the second sampling event were too sparse to conduct the CM tests for radio tags. It is noted,
however, that no significant CM tests were found in the mark-recapture analysis involving
(primarily) darts tags, and given that radio tags were applied systematically to all Chinook
Salmon measuring 50 cm (19.7 in) METF or greater, we assume that a representative sample of
fish measuring 50 cm (19.7 in) METF or greater were radio-tagged in the first sampling event.
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To estimate abundance of spawning salmon in different tributaries within the Yentna River
drainage, the proportion of spawners among tributaries was first estimated. Number of fish by
tributary was then calculated as the product of the proportion by tributary and estimated
abundance (Table I-6).
4.3.2. Coho Salmon
Results from the mark–recapture experiment indicate that radio tags were not deployed in Coho
Salmon proportional to the size distribution of fish in the population. To estimate abundance of
spawning salmon in different tributaries within the mainstem Susitna River drainage, the number
of spawners among tributaries was first estimated within each size stratum. Numbers of fish by
tributary within a size stratum was then calculated as the product of the proportion by tributary
within size stratum and estimated abundance for that size stratum (Table I-9). Numbers of fish
were then summed over size strata for each tributary (Table I-10).
5. DISCUSSION
An estimate of Chinook Salmon abundance for the Susitna River upstream of the Yentna River
confluence was generated after size-stratification. It is unfortunate that the diagnostic KS tests
suggested a stratification point at the higher end of the length scale (78.5 cm METF [30.9 in]),
because it meant the estimate of abundance for fish of the large size category was based on
relatively few recaptures (12 fish). It is noted that the pooled estimate of all Chinook Salmon
measuring 50 cm (19.7 in) METF or greater is 53,246 (22 percent smaller), demonstrating the
influence of size-stratification. The objective to estimate the distribution of the Chinook Salmon
escapements among the tributaries of the Susitna River above the Yentna River was successful.
With the estimate of the Yentna River Chinook Salmon abundance for 2014 complete, the
objective to estimate the system-wide Chinook Salmon escapement in 2014 has now been met.
The marking and capture techniques and choice of locations provided sufficient sample sizes to
achieve a reasonably precise abundance estimate, with a coefficient of variation of 13 percent.
The marking and capture techniques and locations also provided conditions that allowed for
consistent spatial and temporal marking of fish, without being size selective (except for one
instance in the RM 18 east fishwheel). Not having to stratify the data helped to minimize the
variance of the abundance estimate.
Defining fish that entered the experiment was occasionally difficult as there was no stationary
telemetry site at the RM 18 recapture site. It had to be assumed that all fish passing the lower
Yentna stationary telemetry site (approximately RM 9) and staying upstream of that site for at
least 48 hours, continued upstream to the recapture site at RM 18. This is an important
assumption, as it affects the dropout rate, which affects the number of tags out, and thus the
entire abundance estimate. While most radio-tagged fish passing the lower Yentna stationary
telemetry site continued upstream to later be detected in aerial telemetry surveys and confirmed
as in the experiment, some did not.
An estimate of 84,879 Coho Salmon migrating into the Susitna River upstream of the Yentna
River confluence was generated after size-stratification. Without stratification a biased estimate
of approximately 100,000 Coho Salmon is calculated (17 percent larger). It is apparent that
smaller fish are marked at a higher rate than larger fish at the lower Susi tna River fishwheels.
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The objective to estimate the distribution of the Coho Salmon escapements among the tributaries
of the Susitna River above the Yentna River was successful. A weakness in the overall design of
the 2014 project is that we only had two recapture sites, one of which (Montana) was associated
with relatively few fish, and therefore recaptures (4). The small number of recaptures at
Montana compromises the EP spatial test, leaving us to largely assume the fish passing the
Deshka river weir were tagged at the same rate as the other stocks in the drainage.
6. CONCLUSIONS AND RECOMMENDATIONS
The 2014 mark-recapture experiment for Chinook Salmon in the mainstem Susitna River appears
to have been successful. It is recommended, however that the differential tagging rates of fish
50–58 cm (19.7–22.8 in) METF be maintained in future experiments of this kind, but
additionally, that more effort also be directed into tagging larger fish. It is noted that a sizeable
portion of the estimated abundance of Chinook Salmon was based on a relatively small portion
of the recaptured fish. Larger fish are typically tagged via gillnets and concern over the
mortality rate of this method of sampling has hindered tagging larger fish. Adjustments to gillnet
sampling may be required such that more large fish (METF ≥ 58 cm [22.8 in]) can be tagged
without undue mortality. An additional recapture event is recommended on Clear Creek,
replacing the failed attempts on the Chulitna River. Clear Creek is shallower and more
accessible than the Chulitna River site, allowing more attention to the sonar operation, and has a
larger Chinook Salmon escapement, which should result in more recaptured fish. Tethered fish
experiments, crucial to calibration of sonar-derived length data, should also be easier at this site.
The 2014 mark-recapture experiment for Chinook Salmon in the Yentna River appears to have
been successful with the current design. It is recommended, however, that the reasons for the
substantially differential drop-out rates among crews be investigated before further similar work
is done, and efforts taken to standardize the sampling protocol between crews and minimize
handling time. Adding a stationary telemetry site at the RM 18 recapture site would clearly
identify when tagged fish become available for recapture and increase the accuracy of the
dropout rate estimate.
The 2014 mark-recapture experiment for Coho Salmon in the mainstem Susitna River appears to
have been successful. It is, however, recommended that additional recapture sites be considered
in the future that allow assessment of the tagging rates of other stocks. These sites could be
additional weirs or upriver fishwheels.
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Table I-1. Diagnostic tests for mark-recapture data for mainstem Susitna River Chinook Salmon measuring
50.0–78.5 cm METF, 2014.
Testa Parameter
1) CM-Spatialb
Gear Gillnet Fishwheel 1 west
Fishwheel 2 east
Marks 42 148 191
Recaptured 6 66 55
Not recaptured 36 82 137
2) CM-Temporalc
Julian day 142-156 157-162
163-181
Marks 164 120 97
Recaptured 48 42 37
Not recaptured 116 79 60
3) EP-Spatiald
Weir site Deshka R Montana Cr
Inspectede 10,138 952
Marked 116 10
Unmarked 10,022 942
4) EP-Temporalf
Deshka weir Julian day 138-159 160-162
163-167 168-246
Inspectede 1941 2974 2852 2371
Marked 30 25 29 32
Unmarked 1911 2949 2823 2339
5) EP-Temporalg
Montana weir Julian day 174-191 192-203
204-254
Inspectede 339 328 285
Marked 3 6 1
Unmarked 336 322 284
a CM = “Complete Mixing Test” and EP = “Equal Proportions Test” (see text; Arnason et al. 1996).
b χ2 = 17.22, P < 0.001.
c χ2 = 2.332, P = 0.311.
d χ2 =0.01, P = 0.921.
e Number of fish inspected for marks is estimated.
f χ2 = 6.48, P = 0.09.
g χ2 = 3.33, P = 0.189.
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Table I-2. Diagnostic tests for mark-recapture data for mainstem Susitna River Chinook Salmon measuring
78.5 cm METF or greater, 2014.
Testa Parameter
1) CM-Spatialb
Gear Gillnet Fishwheel 1 west
Fishwheel 2 east
Marks 45 24 43
Recaptured 4 5 3
Not recaptured 41 19 40
2) CM-Temporalc
Julian day 142-156 157-162
Marks 45 67
Recaptured 2 10
Not recaptured 43 57
3) EP-Spatiald
Weir site Deshka R Montana Cr
Inspectede 3770 260
Marked 8 4
Unmarked 3762 256
4) EP-Temporalf
Deshka weir Julian day 138-162 162-246
Inspectede 1906 1864
Marked 3 5
Unmarked 1903 1859
5) EP-Temporalg
Montana weir Julian day 174-198 199-254
Inspectede 93 167
Marked 1 3
Unmarked 92 164
a CM = “Complete Mixing Test” and EP = “Equal Proportions Test” (see text; Arnason et al. 1996).
b χ2 = 3.35, P = 0.187
c χ2 = 2.09, P = 0.148
d χ2 = 10.28, P = 0.001
e Number of fish inspected for marks is estimated.
f χ2 = 0.148, P = 0.70
g χ2 = 0, P = 1
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Table I-3. Estimated abundance, number of radio tags deployed, and relative weights (number of spawners
per tag) used to estimate abundance within size stratum for Chinook Salmon spawning upstream from the
lower mainstem tagging site in the Susitna River, 2014.
Size Strata
Estimated
Abundance Estimated SE
Radio Tags
Deployed
Relative Weight
spawners/tag
50.0 - 78.5 cm METF 33,184 2,783 381 86.6
≥ 78.5 cm METF 35,041 10,645 112 312.9
> 50 cm METF 68,225 10,615
Table I-4. Chinook Salmon measuring 50 cm METF or greater spawning distributions, based on weighted
abundance (Table I-3), in the mainstem Susitna River above the Lower River tagging site, 2014.
Estimated
Abundance
Intervals
Location SE 95% lower 95% upper
Susitna River above the mainstem tagging site 68,225 10,615 53,473 94,240
PRM 34–102.4 mainstem Susitna River a 2,098 682 1,064 3,717
Deshka River 14,024 816 12,451 15,667
Eastside Susitna River 15,073 3,398 10873 23,939
Talkeetna River 14,024 3,713 9,622 23,657
PRM 102.4–153.4 mainstem Susitna River b 6,609 2,365 3,781 12,700
Chulitna River 16,397 3,961 11,653 26,708
a PRM 34 upstream to the Chulitna River Confluence.
b Chulitna River Confluence to Devils Canyon.
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Table I-5. Diagnostic tests for mark-recapture data for Yentna River Chinook Salmon >50 cm METF, 2014a.
Test Parameter
1) CM-Spatialb
Gear North Fishwheel South Fishwheel
Gillnet
Marked 311 396 256
Recaptured 16 26 17
Not recaptured 295 370 239
2) CM-Temporalc
Julian day 146-154 155-159 160-176
Marked 335 298 330
Recaptured 25 14 20
Not recaptured 310 284 310
3) EP-Spatiald
Gear East Fishwheel West Fishwheel Gillnet
Inspected 725 540 120
Marked 31 25 3
Unmarked 694 515 117
4) EP-Temporale
East 2nd event fishwheel Julian day 144-157 158-163 164-234
Inspected 322 181 222
Markedh 15 8 8
Unmarked 307 173 214
5) EP-Temporalf
West 2nd event fishwheel Julian day 144-157 158-163 164-234
Inspected 172 213 155
Markedh 8 12 5
Unmarked 164 201 150
6) EP-Temporalg
Both 2nd event fishwheels Julian day 144-157 158-163 164-234
plus gillnet Inspected 513 419 453
Markedh 23 21 15
Unmarked 490 398 438
a CM=”Complete Mixing Test” and EP=”Equal Proportions Test” (see text; Arnason et al. 1996)
b χ2 = 0.77, P =0.68; Marks are estimated.
c χ2 = 2.1, P =0.35; Marks are estimated.
d χ2 =1.1, P = 0.58
e χ2 =0.37, P = 0.83
r χ2 = 1.18, P = 0.55
g χ2 = 1.64, P = 0.44
h Julian days for marked fish adjusted for estimated 3 day lag; see text for details.
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Table I-6. Chinook Salmon spawning distributions in the Yentna River above the RM 6 tagging site, 2014.
Estimated
Abundance
Intervals
Location SE 95% lower 95% upper
Yentna River above tagging site 22,267 2,871 17,466 28,701
Lake Creek drainage 5,163 986 3,496 7,334
Kahiltna River drainage 4,195 855 2,746 6,082
Talachulitna River drainage 1,721 482 892 2,783
Skwentna River drainage, other than the
Talachulinta River drainage
4,303 868 2,824 6,213
Remaining Yentna River drainage, other than the
areas above
6,885 1,214 4,805 9,557
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Table I-7. Diagnostic tests for mark-recapture data for mainstem Susitna River Coho Salmon 40-55 cm
METF, 2014a.
Test
1) CM-Spatialb
Gear Fishwheel 1 west Fishwheel 2 east
Marks 191 203
Recaptured 34 4
Not recaptured 157 199
2) CM-Temporalc
Julian day 188-207 208-212 213-232
Marks 155 128 111
Recaptured 13 17 8
Not recaptured 142 111 103
3) EP-Spatiald
Weir site Deshka R Montana Cr
Inspectede 3,257 402
Marked 36 2
Unmarked 3,221 400
4) EP-Temporalf
Deshka weir Julian day 185-216 217-228 229-245
Inspectede 804 970 1,482
Marked 10 6 20
Unmarked 747 1,012 1,462
5) EP-Temporalg
Montana weir
a CM=”Complete Mixing Test” and EP=”Equal Proportions Test” (see text; Arnason et al. 1996)
b χ2 = 26.51, P =<0.001.
c χ2 = 2.98, P =0.225.
d χ2 =0.763, P = 0.382.
e Number of fish inspected for marks is estimated.
f χ2 = 3.05,P=0.217
g Insufficient recaptures to conduct test (2 recaptures at Montana weir in size class 40-55 cm).
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Table I-8. Diagnostic tests for mark-recapture data for mainstem Susitna River Coho Salmon >55 cm METF,
2014a.
Test
1) CM-Spatialb
Gear Fishwheel 1 west Fishwheel 2 east
Marks 95 93
Recaptured 25 9
Not recaptured 70 84
2) CM-Temporalc
Julian day 188-207 208-212 213-232
Marks 70 52 66
Recaptured 17 10 7
Not recaptured 53 42 59
3) EP-Spatiald
Weir site Deshka R Montana Cr
Inspectede 8,288 529
Marked 32 2
Unmarked 8,256 527
4) EP-Temporalf
Deshka weir Julian day 185-216 217-228 229-245
Inspectede 1,817 2,505 3,998
Marked 5 6 21
Unmarked 1,812 2,499 3,976
5) EP-Temporalg
Montana weir
a CM=”Complete Mixing Test” and EP=”Equal Proportions Test” (see text; Arnason et al. 1996)
b χ2 = 7.69, P =0.006
c χ2 = 4.35, P =0.113
d χ2 ~0, P ~ 1
e Number of fish inspected for marks is estimated.
f χ2 = 4.01, P = 0.13
g Insufficient recaptures to conduct test (2 recaptures at Montana weir in size class >55cm).
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Table I-9. Estimated abundance, number of radio tags deployed, and relative weights (number of spawners
per tag) used to estimate abundance within size stratum for Coho Salmon spawning upstream from the lower
mainstem tagging site in the Susitna River, 2014.
Size Strata
Estimated
Abundance Estimated SE
Radio Tags
Deployeda
Relative Weight
spawners/tag
40-55 cm METF 37,069 6,495 394 94
≥55 cm METF 47,810 7,667 188 254
> 40 cm METF 84,879 9,550
a Available to estimate spawning distribution
Table I-10. Coho Salmon spawning distributions, based on weighted abundance (Table I-3), in the mainstem
Susitna River above the lower river tagging site, 2014.
Estimated
Abundance
Intervals
Location SE 95% lower 95% upper
Susitna River above the mainstem tagging site 84,879 9,550 68,799 106,083
PRM 34–102.4 mainstem Susitna River a 10,889 2,096 7,792 15,979
Deshka River 15,377 1,138 13,737 18,215
Eastside Susitna River 16,515 2,790 12,446 23,312
Talkeetna River 12,130 2,244 8,797 17,598
PRM 102.4–153.4 mainstem Susitna River b 6,184 1,414 4,030 9,559
Chulitna River 23,783 3,788 18,307 33,099
a PRM 34 upstream to the Chulitna River Confluence
b Chulitna River Confluence to Devils Canyon
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix I – Page 1 October 2015
Figure I-1. Empirical cumulative distribution functions (ECDF) of length (in mm) of Chinook Salmon
(METF ≥ 50 cm) marked during first event sampling at the lower mainstem Susitna River tagging site and all
recaptures during second event sampling at the Deshka River and Montana Creek weirs, 2014.
500 600 700 800 900 1000
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Marks : Pooled Deshka-Montana
Length mmFn(x)Marked
Recaptured
D_max= 0.145
D_max at 770 mm
p-value= 0.016
Obs in Marked = 494
Obs in Recaptured = 138
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix I – Page 2 October 2015
Figure I-2. Empirical cumulative distribution functions (ECDF) of length (in millimeters, mm) of Chinook
(METF ≥ 500 mm) inspected for marks and all recaptured salmon during second event sampling at the
Deshka River weir, 2014.
500 600 700 800 900
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Captures : Deshka
Length mmFn(x)Captured
Recaptured
D_max= 0.21
D_max at 785 mm
p-value= 0
Obs in Captured = 251
Obs in Recaptured = 124
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix I – Page 3 October 2015
Figure I-3. Empirical cumulative distribution functions (ECDF) of length (in mm) of Chinook Salmon
(METF ≥ 500 mm) inspected for marks and all recaptured salmon during second event sampling at the
Montana Creek weir, 2014.
500 600 700 800 900
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Captures : Montana
Length mmFn(x)Captured
Recaptured
D_max= 0.372
D_max at 590 mm
p-value= 0.026
Obs in Captured = 226
Obs in Recaptured = 14
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix I – Page 4 October 2015
Figure I-4. The 4-day lag between total weir count and radio-tagged Chinook Salmon at the Deshka River
weir, 2014.
246810DESHKA
DAYRadiotagged05/28 06/02 06/07 06/12 06/17 06/22 06/27 07/02 07/07 07/12 07/17 07/22 07/27
04008001200DAYWeir Count05/28 06/02 06/07 06/12 06/17 06/22 06/27 07/02 07/07 07/12 07/17 07/22 07/27
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix I – Page 5 October 2015
Figure I-5. Empirical cumulative distribution functions of METF length (mm) of all Chinook Salmon (> 500
mm) marked during first event at the lower Yentna River tagging site at RM 6 and of all salmon recaptured
during second event sampling at RM 18 of the lower Yentna River, 2014.
500 600 700 800 900 1000 1100
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Marks : Pooled Fishwheel and Gillnet
Length mmFn(x)Marked
Recaptured
D_max= 0.088
D_max at 640 mm
p-value= 0.654
Obs in Marked = 1277
Obs in Recaptured = 59
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix I – Page 6 October 2015
Figure I-6. Empirical cumulative distribution functions of METF length (mm) of Chinook Salmon (> 500
mm) inspected for marks during second event sampling at the Yentna RM 18 east fishwheel, and all salmon
recaptured during inspection in 2014.
500 600 700 800 900
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Captures : East Wheel
Length mmFn(x)Captured
Recaptured
D_max= 0.196
D_max at 610 mm
p-value= 0.122
Obs in Captured = 719
Obs in Recaptured = 31
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix I – Page 7 October 2015
Figure I-7. Empirical cumulative distribution functions of METF length (mm) of Chinook Salmon (>500
mm) inspected for marks during second event sampling at the Yentna RM 18 west fishwheel, and all salmon
recaptured during inspection in 2014.
500 600 700 800 900 1000 1100
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Captures : West Wheel
Length mmFn(x)Captured
Recaptured
D_max= 0.131
D_max at 625 mm
p-value= 0.666
Obs in Captured = 536
Obs in Recaptured = 25
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix I – Page 8 October 2015
Figure I-8. Empirical cumulative distribution functions of METF length (mm) of Chinook Salmon (>500
mm) inspected for marks during second event sampling (pooled data) and all salmon recaptured during
inspection at Yentna RM 18 in 2014.
500 600 700 800 900 1000 1100
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Captures : Pooled Data
Length mmFn(x)Captured
Recaptured
D_max= 0.053
D_max at 550 mm
p-value= 0.974
Obs in Captured = 1255
Obs in Recaptured = 59
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix I – Page 9 October 2015
Figure I-9. Timing at Yentna River second event fishwheels (RM 18) of all fish caught >500 mm METF and
of recaptures.
Catch >=500mm
Recapture DayFrequency140150160 170 180 1900100200300400
Recaptures
Recapture DayFrequency140150160 170 180 190051015
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Appendix I – Page 10 October 2015
Figure I-10. Empirical cumulative distribution functions of METF length (mm) of all Coho Salmon (> 400
mm) marked during first event at the lower mainstem Susitna River tagging site and of all salmon recaptured
during second event sampling at the Deshka River and Montana Creek weirs during second event, 2014.
400 450 500 550 600
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Marks : Pooled Wheels ( 400 - 1000 mm)
Length mmFn(x)Marked
Recaptured
D_max= 0.247
D_max at 525 mm
p-value= 0.001
Obs in Marked = 582
Obs in Recaptured = 72
STUDY COMPLETION REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Appendix I – Page 11 October 2015
Figure I-11. Empirical cumulative distribution functions of METF length (mm) of Coho Salmon (> 400 mm)
inspected for marks during second event sampling at the Deshka River weir, 2014 and of all salmon
recaptured during inspection.
400 450 500 550 600 650
0.0
0.2
0.4
0.6
0.8
1.0
Recaptures - Captures : Deshka ( 400 - 1000 mm)
Length mmFn(x)Captured
Recaptured
D_max= 0.286
D_max at 565 mm
p-value= 0
Obs in Captured = 304
Obs in Recaptured = 68