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Susitna‐Watana Hydroelectric Project Document
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Title:
Salmon escapement study, Study plan Section 9.7 : Initial study report --
Part A: Sections 1-6, 8-10
SuWa 223
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:
Initial study report
AEA‐identified series, if specified:
Series (ARLIS‐assigned report number):
Susitna-Watana Hydroelectric Project document number 223
Existing numbers on document:
Published by:
[Anchorage : Alaska Energy Authority, 2014]
Date published:
June 2014
Published for:
Alaska Energy Authority
Date or date range of report:
Volume and/or Part numbers:
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Document type:
Pagination:
231 pages in various pagings
Related work(s):
The following parts of Section 9.7 appear in separate files: Part
A ; Part B ; Part C ; Part D.
Pages added/changed by ARLIS:
Notes:
Part A includes appendices A-I.
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
Initial Study Report
Part A: Sections 1-6, 8-10
Prepared for
Alaska Energy Authority
Prepared by
LGL Alaska Research Associates, Inc. &
Alaska Department of Fish and Game, Division of Sport Fish
June 2014
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page i June 2014
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 ...................................................................................4
4.1.3. Spaghetti-tagging .............................................................................5
4.1.4. Daily Tagging Goals ........................................................................5
4.1.5. Numbers and Size of Marked and Unmarked Fish at Selected
Locations ..........................................................................................6
4.1.6. Examining Handling-Induced Changes in Behavior .......................7
4.1.7. Assessing Any Stock- and Size-selective Capture...........................8
4.1.8. Variances........................................................................................10
4.2. Objective 2: Determine the migration behavior and spawning locations of
radio-tagged fish in the Lower, Middle, and Upper Susitna River ..................12
4.2.1. Fixed-station Monitoring ...............................................................13
4.2.2. Aerial Telemetry Surveys ..............................................................14
4.2.3. Boat and Ground Surveys ..............................................................16
4.2.4. Variances........................................................................................16
4.3. Objective 3: Characterize adult salmon migration behavior and timing within
and above Devils Canyon ................................................................................16
4.3.1. Fixed-station Monitoring ...............................................................17
4.3.2. Aerial Telemetry Surveys ..............................................................17
4.3.3. Aerial Spawner Surveys .................................................................17
4.3.4. Assess the Feasibility of Using Sonar to Enumerate Salmon and
Resident Fish at the Proposed Dam Site ........................................18
4.3.5. Variances........................................................................................18
4.4. Objective 4: Use available technology to document salmon spawning
locations in turbid water...................................................................................18
4.4.1. Sonar Equipment and Methods ......................................................19
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page ii June 2014
4.4.2. Sonar Data Analysis and Reporting ...............................................19
4.4.3. Variances........................................................................................20
4.5. Objective 5: Compare historical and current data on run timing, distribution,
relative abundance, and specific locations of spawning and holding salmon..20
4.5.1. Variances........................................................................................21
4.6. Objective 6: Generate counts of adult Chinook salmon spawning in the
Susitna River and its tributaries .......................................................................21
4.6.1. Variances........................................................................................22
4.7. Objective 7: Collect tissue samples to support the Fish Genetics Study .........22
4.7.1. Variances........................................................................................22
4.8. Objective 8: Estimate the system-wide Chinook and coho salmon escapement
to the Susitna River above Yentna River and the distribution of those fish
among tributaries of the Susitna River.............................................................22
4.8.1. Variances........................................................................................23
5. Results .............................................................................................................................. 24
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. ...............................................................................24
5.1.1. Fish Capture ...................................................................................25
5.1.2. Radio-tagging .................................................................................26
5.1.3. Spaghetti-tagging ...........................................................................27
5.1.4. Numbers and Size of Marked and Unmarked Fish at Selected
Locations ........................................................................................27
5.1.5. Examining Handling-Induced Changes in Behavior .....................30
5.1.6. Assessing Any Stock- and Size-selective Capture.........................30
5.2. Objective 2: Determine the migration behavior and spawning locations of
radio-tagged fish in the Lower, Middle, and Upper Susitna River ..................34
5.2.1. Tag Returns ....................................................................................34
5.2.2. Stock Classifications and Spawning Locations – Lower River .....34
5.2.3. Stock Classifications and Spawning Locations – Yentna River ....35
5.2.4. Stock Classifications and Spawning Locations – Middle and Upper
River ...............................................................................................35
5.2.5. Roaming Behavior in the Middle River .........................................38
5.3. Objective 3: Characterize adult salmon migration behavior and timing within
and above Devils Canyon ................................................................................38
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page iii June 2014
5.3.1. Species, Number, and Destination .................................................38
5.3.2. Migration Timing for Fish Passing Above Devils Canyon ...........39
5.3.3. Relative Abundance of Salmon Passing Above Devils Canyon ....39
5.3.4. Size of Chinook Salmon Tracked In and Above Devils Canyon...40
5.3.5. Aerial Spawner Surveys .................................................................40
5.3.6. Assess the Feasibility of Using Sonar to Enumerate Salmon and
Resident Fish at the Proposed Dam Site ........................................42
5.4. Objective 4: Use available technology to document salmon spawning
locations in turbid water...................................................................................42
5.5. Objective 5: Compare historical and current data on run timing, distribution,
relative abundance, and specific locations of spawning and holding salmon..42
5.5.1. Run Timing ....................................................................................42
5.5.2. Relative Abundance .......................................................................43
5.5.3. Spawning and Holding Salmon Locations .....................................43
5.6. Objective 6: Generate counts of adult Chinook salmon spawning in the
Susitna River and its tributaries .......................................................................44
5.6.1. Observer Efficiency During Aerial Spawner Surveys ...................44
5.6.2. Chinook Salmon Mark Rates: Indian River vs. Portage Creek ....45
5.6.3. Estimated Abundance Above Curry (Chinook, Chum, and Pink
Salmon) ..........................................................................................45
5.6.4. Estimated Abundance Above Devils Canyon (Chinook Salmon) .46
5.7. Objective 7: Collect tissue samples to support the Fish Genetics Study .........46
5.8. Objective 8: Estimate the system-wide Chinook and coho salmon escapement
to the Susitna River above Yentna River and the distribution of those fish
among tributaries of the Susitna River.............................................................47
6. Discussion......................................................................................................................... 47
6.1. Fish Capture and Tagging ................................................................................47
6.1.1. Catch Rates ....................................................................................47
6.1.2. Use of ARIS to Assess Fishwheel Effectiveness and Fish
Approach Behavior ........................................................................48
6.1.3. Size Selectivity...............................................................................48
6.2. Use of Tributary Weirs (and Sonar) to Assess Numbers and Size of Marked
and Unmarked Fish ..........................................................................................50
6.2.1. Indian River Weir ..........................................................................51
6.3. Migration Behavior and Spawning Locations of Salmon in the Lower, Middle,
and Upper Susitna River ..................................................................................51
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page iv June 2014
6.3.1. Lower River ...................................................................................51
6.3.2. Middle and Upper River ................................................................52
6.4. Salmon Migration Behavior and Timing Within and Above Devils Canyon ..52
6.5. Use of ARIS to Document Spawning Locations in Turbid Water ...................53
6.6. Estimated Abundance of Chinook Salmon Above Devils Canyon .................54
6.7. Study Interdependencies ..................................................................................55
7. Completing the Study ..................................................................................................... 55
8. Literature Cited .............................................................................................................. 55
9. Tables ............................................................................................................................... 58
10. Figures .............................................................................................................................. 77
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page v June 2014
LIST OF TABLES
Table 4.3-1. Aerial spawner surveys conducted in the Middle and Upper River by
location and date, 2013. .........................................................................................................59
Table 4.4-1. Survey effort and observations using ARIS to identify Chinook salmon
spawning behavior in turbid water, 2013. ..............................................................................60
Table 4.4-2. Survey effort and observations using ARIS to identify chum salmon
spawning behavior in turbid water, 2013. ..............................................................................61
Table 5.1-2. Number of tagged and untagged adult salmon counted at the Deshka River,
Montana Creek, and Indian River weirs in 2013, by species and size category. ...................62
Table 5.2-1. Fate classifications for radio-tagged fish in 2013, by species and release
location. ..................................................................................................................................63
Table 5.2-2. The proportions of radio-tagged fish of known fate 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, 2013. ............................................................................................................................66
Table 5.2-3. Farthest upstream detection locations for radio-tagged fish that eventually
entered a Lower River tributary, 2013. ..................................................................................67
Table 5.3-1. Details of the radio-tagged fish that approached or passed the Middle River
impediments, 2013. ................................................................................................................68
Table 5.3-2. Destinations of radio-tagged Chinook salmon that passed each Middle River
impediment, 2013. .................................................................................................................74
Table 5.5-1. Average percent distribution of spawning salmon in slough habitats of the
Middle River from 1981 to 1985, and confirmed spawning locations in 2012 and
2013. .......................................................................................................................................75
LIST OF FIGURES
Figure 3-1. Susitna River watershed showing fish capture sites (fishwheels) and the
locations of fixed-station telemetry receiver sites, 2013........................................................78
Figure 4.1-1. Middle River Segment showing sites for fish capture (sites 1, 2, and 3),
ARIS, rotary screw trap (RST), Curry camp, and the Lane Creek and Gateway fixed-
station receivers, 2013. ..........................................................................................................79
Figure 4.3-1. Aerial spawner survey extent for Indian River and tributaries in and above
Devils Canyon, 2013. .............................................................................................................80
Figure 5.2-1. Fate classifications for radio-tagged fish released in the lower river (left
panels) or at Curry (right panels), by species/life history stage, 2013. ..................................81
Figure 5.3-1. Daily numbers of Chinook salmon that approached and passed each of the
three Middle River impediments in 2013. .............................................................................82
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page vi June 2014
Figure 5.3-2. Daily number of radio-tagged Chinook salmon that held below Impediment
3 in 2013. Each of the three fish is shown using a unique color. ..........................................83
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page vii June 2014
LIST OF APPENDICES
Appendix A: Fish Capture and Tagging
Table A-1. Number of salmon radio-tagged at two fishwheel sites and from gillnets in
the Lower River, 2013. ........................................................................................................... 1
Table A-2. Number of Chinook salmon radio-tagged at two fishwheel sites and in
gillnets in the Yentna River, 2013. ......................................................................................... 1
Table A-3. Number of salmon radio- and spaghetti-tagged at three fishwheel sites and in
a beach seine in the Middle River, 2013. ................................................................................ 2
Table A-4. Number of fish sampled at the Middle River fishwheels (length, fin clip, and
scales) and transferred to the FDA Study to be surgically radio-tagged, 2013. ..................... 3
Table A-5. Number of salmon captured at two fishwheel sites and in gillnets in the
Lower River, 2013. ................................................................................................................. 3
Table A-6. Number of Chinook salmon captured at two fishwheel sites and in gillnets in
the Yentna River, 2013. .......................................................................................................... 4
Table A-7. Number of salmon caught in the Lower River and Yentna River and their
length statistics, 2013. ............................................................................................................. 4
Table A-8. Number of salmon captured at three fishwheel sites and in a beach seine in
the Middle River, by size category, 2013. .............................................................................. 5
Figure A-1. Daily fishing effort (hours) and rotational speed (RPM) at two fishwheel
sites in the Lower River, 2013. ............................................................................................... 6
Figure A-2. Daily gillnet effort (hours) in the Lower River, by mesh size, 2013. ........................ 6
Figure A-3. Daily fishing effort (hours) at two fishwheel sites in the Yentna River, 2013. ......... 7
Figure A-4. Daily gillnet effort (hours) in the Yentna River, by mesh size, 2013. ....................... 7
Figure A-5. Daily fishing effort (hours) and rotational speed (RPM) at three fishwheel
sites in the Middle River, 2013. .............................................................................................. 8
Figure A-6. Daily number of radio tags applied to adult Chinook, pink, and coho salmon
captured at two fishwheel sites and in gillnets in the Lower River, 2013. ............................. 9
Figure A-7. Daily number of radio tags applied to adult Chinook salmon captured at two
fishwheel sites and in gillnets in the Yentna River, 2013. ...................................................... 9
Figure A-8. Daily number of radio tags applied to adult Chinook, sockeye, pink, chum,
and coho salmon captured at three fishwheel sites in the Middle River, 2013. .................... 10
Figure A-9. Daily sampling effort, and the amount of imagery reviewed (review effort),
for two ARIS units operated immediately downstream of the fishwheel at Site 1 in
the Middle River, 2013. ........................................................................................................ 11
Figure A-10. Daily catch-per-unit-effort at the Lower River fishwheels, by species, and
the Susitna River discharge at Sunshine, 2013. .................................................................... 12
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page viii June 2014
Figure A-11. Daily catch-per-unit-effort for Chinook salmon at the Yentna River
fishwheels, and the Yentna River discharge at Lake Creek, 2013. ....................................... 12
Figure A-12. Daily catch-per-unit-effort at the Middle River fishwheels, by species, and
the Susitna River discharge at Gold Creek, 2013. ................................................................ 13
Figure A-13. Daily number of radio tags deployed at the Middle River fishwheels
relative to fishwheel catches in the 1980s, 2012, and 2013. ................................................. 14
Figure A-14. Daily number of spaghetti tags applied to adult pink, chum, and coho
salmon captured at three fishwheel sites in the Middle River, 2013. ................................... 15
Figure A-15. Cumulative length-frequency distributions for salmon radio-tagged in the
Middle River and inspected and recaptured at the Indian River weir site, by species,
2013. ...................................................................................................................................... 16
Figure A-16. Cumulative length-frequency distributions for salmon spaghetti-tagged in
the Middle River and inspected and recaptured at the Indian River weir site, by
species, 2013. ........................................................................................................................ 17
Figure A-17. Catch-per-unit-effort, or the number of targets counted per hour of imagery
reviewed, on the ARIS (Unit 1) located immediately downstream of the Site 1
fishwheel, 2013. .................................................................................................................... 18
Figure A-18. Comparison of the number of adult salmon (≥ 50 cm METF) captured at
the Site 1 fishwheel and concurrent net upstream counts of fish on the ARIS unit
(Unit 1) located immediately downstream of the fishwheel, 2013. ...................................... 18
Figure A-19. Number of fish counted using ARIS at Site 1 as a function of the distance
from each unit where they were first detected in the field of view, by time period and
size category, 2013. ............................................................................................................... 19
Figure A-20. Diel migration of fish counted using ARIS (Unit 1) at Site 1, by size
category, 2013. ...................................................................................................................... 20
Figure A-21. Cumulative length-frequency distributions for salmon captured in the
Lower River, by species and capture site, 2013. ................................................................... 21
Figure A-22. Cumulative length-frequency distributions for salmon caught and radio-
tagged in the Lower River, by species, 2013. ....................................................................... 22
Figure A-23. Cumulative length-frequency distributions for salmon radio-tagged in the
Lower River and inspected and recaptured at the Deshka River and Montana Creek
weir sites, by species, 2013. .................................................................................................. 23
Figure A-24. Cumulative length-frequency distribution for Chinook salmon captured in
the Yentna River, by capture site, 2013. ............................................................................... 24
Figure A-25. Cumulative length-frequency distribution for Chinook salmon caught and
radio-tagged in the Yentna River, 2013. ............................................................................... 24
Figure A-26. Cumulative length-frequency distributions for salmon captured in the
Middle River, by species and capture site, 2013. ................................................................. 25
Figure A-27. Cumulative length-frequency distributions for salmon caught, radio-tagged,
and spaghetti-tagged in the Middle River, by species, 2013. ............................................... 26
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page ix June 2014
Appendix B: Daily Fish Passage at Weir Sites in the Lower and Middle River Segments
Table B-1. Deshka River weir daily passage rates and tag recaptures, by species, 2013. ............. 1
Table B-2. Length statistics for tagged and untagged adult salmon sampled at the Deshka
River, Montana Creek, and Indian River weirs in 2013, by species. ...................................... 4
Table B-3. Montana Creek weir daily passage rates and tag recaptures, by species, 2013. .......... 5
Table B-4. Indian River weir daily passage rates and tag recaptures, by species, 2013. ............... 8
Figure B-1. Daily amount of video imagery collected at the Indian River weir and the
type of sampling method used to review the imagery (15-min sub-sample, full-hour
sample), June 26 to August 20, 2013. ................................................................................... 10
Figure B-2. Net passage of adult salmon that were inspected for tags, and the percent that
were tagged (mark rate), at the Indian River weir from June 26 to August 20, 2013........... 11
Figure B-3. Number of rainbow trout, Dolly Varden, Arctic grayling, longnose sucker,
round whitefish, and humpback whitefish counted on video imagery collected at the
Indian River weir, by direction of movement, 2013. ............................................................ 12
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, 2013. .............................................................................................................. 1
Table C-2. Monitoring efficiency (percent operational) of fixed-station receivers in the
Lower River Basin in 2013, by week. ..................................................................................... 3
Table C-3. Monitoring efficiency (percent operational) of fixed-station receivers in the
Middle and Upper River basins in 2013, by week. ................................................................. 4
Table C-4. List of the aerial telemetry surveys conducted through September 21, 2013,
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), 2013. ...................................................................... 1
Table D-2. Summary of monitoring effort at potential spawning sites for Chinook
salmon in the Middle River, 2013. .......................................................................................... 2
Table D-3. Summary of monitoring effort at potential spawning sites for chum salmon in
the Middle River, 2013. .......................................................................................................... 3
Table D-4. Summary of monitoring effort at potential spawning sites for pink salmon in
the Middle River, 2013. .......................................................................................................... 4
Table D-5. Summary of monitoring effort at potential spawning sites for sockeye salmon
in the Middle River, 2013. ...................................................................................................... 5
Table D-6. Details of impediment-passage events for radio-tagged fish, 2013. ............................ 6
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page x June 2014
Table D-7. Number of Chinook salmon counted during aerial spawner surveys, by
location and survey period, 2013. ......................................................................................... 11
Table D-8. Summary of weather variability during the adult salmon aerial spawner
surveys in the Middle and Upper rivers, 2013. ..................................................................... 12
Table D-9. Summary of survey condition rankings during the adult salmon aerial
spawner surveys in the Middle and Upper rivers, 2013. ....................................................... 12
Figure D-1. Relative frequencies of tributary use by radio-tagged salmon released in the
Lower River, by species, 2013. ............................................................................................. 13
Figure D-2. Potential mainstem spawning sites for radio-tagged Chinook salmon in the
Lower River, 2013. ............................................................................................................... 14
Figure D-3. Potential mainstem spawning sites for radio-tagged coho salmon in the
Lower River, 2013. ............................................................................................................... 15
Figure D-4. Potential mainstem spawning sites for radio-tagged coho salmon in the
Middle River, 2013. .............................................................................................................. 16
Figure D-5. Potential mainstem spawning sites for radio-tagged pink salmon in the
Lower River, 2013. ............................................................................................................... 17
Figure D-6. Potential mainstem spawning sites for radio-tagged pink salmon in the
Middle River, 2013. .............................................................................................................. 18
Figure D-7. Relative frequencies of tributary use by radio-tagged salmon released in the
Middle River, by species, 2013. ............................................................................................ 19
Figure D-8. Potential mainstem spawning sites for radio-tagged Chinook salmon in the
Middle River, 2013. .............................................................................................................. 20
Figure D-9. Potential mainstem spawning sites for radio-tagged chum salmon in the
Lower River, 2013. ............................................................................................................... 21
Figure D-10. Potential mainstem spawning sites for radio-tagged chum salmon in the
Middle River, 2013. .............................................................................................................. 22
Figure D-11. Potential mainstem spawning sites for radio-tagged sockeye salmon in the
Lower River, 2013. ............................................................................................................... 23
Figure D-12. Potential mainstem spawning sites for radio-tagged sockeye salmon in the
Middle River, 2013. .............................................................................................................. 24
Figure D-13. Summary of Chinook salmon observations during aerial spawner surveys
in the Middle and Upper rivers, 2013. .................................................................................. 25
Appendix E: Radio Tag Recoveries
Table E-1. Tag recovery information for fish released in the Lower River and Yentna
River, 2013. ............................................................................................................................. 1
Table E-2. Tag recovery information for fish released in the Middle River, 2013. ...................... 3
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page xi June 2014
Appendix F: Tracking Histories of Chinook Salmon Above Impediment 3
Table F-1. Summary of migration and spawning behavior for three radio-tagged Chinook
salmon after they passed Impediment 3, 2013. ....................................................................... 1
Figure F-1. Tracking history of a radio-tagged Chinook salmon (tag #241) that was
detected above Impediment 3, 2013. ...................................................................................... 2
Figure F-2. Tracking history of a radio-tagged Chinook salmon (tag #272) that was
detected above Impediment 3, 2013. ...................................................................................... 3
Figure F-3. Tracking history of a radio-tagged Chinook salmon (tag #395) that was
detected above Impediment 3, 2013. ...................................................................................... 4
Appendix G: Feasibility Study Assessing Fish Counts with Sonar in Watana Canyon, 2013
Table G-1. Characteristics of three sites surveyed with ARIS in July, 2013. ................................ 8
Figure G-1. Location of study sites in the Watana Canyon reach of the Susitna River for
evaluating feasibility of sonar for counting fish, July, 2013. .................................................. 9
Figure G-2. Susitna River discharge at the US Geological Survey (USGS) gauge at
Tsusena Creek for the period July 1 through August 31, 2013. ........................................... 10
Figure G-3. Series of still images (top left to right then bottom left to right) that show an
adult Chinook salmon (inside the white circles) migrating through the ARIS sonar
sample volume in Watana Canyon at Site 1 on July 20, 2013. ............................................. 11
Photo G-1. Aluminum H-mount frame used to deploy the ARIS 1200 sonar at Site 1
during the Watana Canyon sonar feasibility study, July, 2013. ............................................ 12
Photo G-2. Aerial view of Site 1 from the sonar feasibility study, July 22, 2013. ...................... 12
Photo G-3. Ortho-rectified aerial photograph of Site 1 assessed for sonar monitoring
suitability in the Watana Canyon reach of the Susitna River, July, 2013. ............................ 13
Photo G-4. Aerial view of Site 2 of the sonar feasibility study, July, 2013. ............................... 13
Photo G-5. Ortho-rectified aerial photographs of Site 2 assessed for sonar monitoring
suitability in the Watana Canyon reach of the Susitna River, 2013. .................................... 14
Photo G-6. Ortho-rectified aerial photographs of Site 3 assessed for sonar monitoring
suitability in the Watana Canyon reach of the Susitna River, 2013. .................................... 14
Appendix H: Abundance Estimates for Chinook, Pink, and Chum Salmon above Curry,
and Chinook Salmon Above Devils Canyon
Table H-1. Estimated observer efficiencies during aerial spawner surveys for Chinook
salmon conducted by AEA and ADF&G upstream of the Indian River weir on July
25, 2013. .................................................................................................................................. 1
Table H-2. Recapture matrix for large Chinook salmon radio-tagged at the Middle River
fishwheels, and inspected for tags at the Indian River weir, 2013.......................................... 2
Table H-3. Estimated abundance of large Chinook, chum, and pink salmon above the
Middle River Gateway fixed station (PRM 130.1), 2013. ...................................................... 3
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FERC Project No. 14241 Part A - Page xii June 2014
Table H-4. Recapture matrix for chum salmon radio-tagged at the Middle River
fishwheels and inspected for tags at the Indian River weir, 2013........................................... 4
Table H-5. Recapture matrix for pink salmon radio-tagged at the Middle River
fishwheels and inspected for tags at the Indian River weir, 2013........................................... 5
Appendix I: Abundance estimates for Chinook salmon in the Susitna River Drainage and
Coho Salmon Above the Yentna River
Table I-1. Tests for temporal and spatial variation in probability of capture for mainstem
Susitna River Chinook salmon 50.0–65.9 cm METF, 2013. .................................................. 7
Table I-2. Tests for temporal and spatial variation in probability of capture for mainstem
Susitna River Chinook salmon 66.0–77.4 cm METF, 2013. .................................................. 8
Table I-3. Tests for temporal and spatial variation in probability of capture for mainstem
Susitna River Chinook salmon measuring 77.5 cm METF or greater, 2013. ......................... 9
Table I-4. 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, 2013. .............................................................................................................. 10
Table I-5. Chinook salmon spawning distributions, based on weighted abundance (Table
I-4), in the mainstem Susitna River above the lower river tagging site, 2013. ..................... 10
Table I-6. Tests for temporal and spatial variation in probability of capture for mainstem
Susitna River coho salmon 40.0–47.9 cm METF, 2013. ...................................................... 11
Table I-7. Tests for temporal and spatial variation in probability of capture for mainstem
Susitna River coho salmon 48.0–53.4 cm METF, 2013. ...................................................... 12
Table I-8. Tests for temporal and spatial variation in probability of capture for mainstem
Susitna River coho salmon measuring 53.5 cm METF or greater, 2013. ............................. 13
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, 2013. ........................................................................................................................... 14
Table I-10. Coho salmon spawning distributions, based on weighted abundance (Table
I-9), in the mainstem Susitna River above the lower river tagging site, 2013. ..................... 14
Figure I-1. Empirical cumulative distribution functions (ECDF) of length (in mm) of all
Chinook salmon marked during first event sampling at the lower mainstem Susitna
River tagging site and all recaptures during second event sampling, 2013. ......................... 15
Figure I-2. Empirical cumulative distribution functions (ECDF) of length (in mm) of
Chinook salmon inspected for marks and all recaptured salmon during second event
sampling at the Deshka River weir, 2013. ............................................................................ 16
Figure I-3. Empirical cumulative distribution functions (ECDF) of length (in mm) of
Chinook salmon inspected for marks and all recaptured salmon during second event
sampling at the Montana Creek weir, 2013. ......................................................................... 17
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Figure I-4. Empirical cumulative distribution functions (ECDF) of length (in mm) of all
coho salmon marked during first event sampling at the lower mainstem Susitna
River tagging site and all recaptures during second event sampling, 2013. ......................... 18
Figure I-5. Empirical cumulative distribution functions (ECDF) of length (in mm) of
coho salmon inspected for marks and all recaptured salmon during second event
sampling at the Deshka River weir, 2013. ............................................................................ 19
Figure I-6. Empirical cumulative distribution functions (ECDF) of length (in mm) of
coho salmon inspected for marks and all recaptured salmon during second event
sampling at the Montana Creek weir, 2013. ......................................................................... 20
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LIST OF ACRONYMS, ABBREVIATIONS, AND DEFINITIONS
Abbreviation Definition
ADF&G Alaska Department of Fish and Game
AEA Alaska Energy Authority
ARIS Adaptive Resolution Imaging Sonar
ATS Advanced Telemetry Systems, Inc.
cfs cubic feet per second
CIRWG Cook Inlet Region Working Group
cm centimeter
CPUE catch per unit effort
DIDSON Dual Frequency Identification Sonar
FERC Federal Energy Regulatory Commission
FL fork length
ft feet
ft/s feet per second
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
LZ landing zone
m Meter
mi mile
m/s meters per second
METF mid-eye to fork
MHW mean high water
MHz Megahertz
oz ounce
PRM Project River Mile
Project Susitna-Watana Hydroelectric Project
RPM revolutions per minute
RSP Revised Study Plan
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Abbreviation Definition
RST revised statute trail
SPD study plan determination
USGS United States Geological Survey
W watt
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1. INTRODUCTION
On December 14, 2012, Alaska Energy Authority (AEA) filed its Revised Study Plan (RSP) with
the Federal Energy Regulatory Commission (FERC or Commission) for the Susitna-Watana
Hydroelectric Project, FERC Project No. 14241, which included 58 individual study plans (AEA
2012). Included within the RSP was the Salmon Escapement Study, Section 9.7. RSP Section
9.7 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).
On February 1, 2013, FERC staff issued its study determination (February 1 Study Plan
Determination [SPD]) for 44 of the 58 studies, approving 31 studies as filed and 13 with
modifications. RSP Section 9.7 was one of the 13 approved with modifications. In its February
1 SPD, FERC recommended the following:
We recommend the study be modified to require AEA to extend the operation of its Curry Station
fishwheels at RM 120 through the entire month of September.
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 into the project area.
On April 26, 2013, the Commission issued a determination requiring no additional changes to
this study. AEA adopted the modifications outlined in FERC’s February 1 SPD as part of the
approved study plan.
Following the first study season, FERC’s regulations for the Integrated Licensing Process (ILP)
require AEA to “prepare and file with the Commission an initial study report describing its
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)) This Initial
Study Report on Salmon Escapement has been prepared in accordance with FERC’s ILP
regulations and details AEA’s status in implementing the study, as set forth in the FERC-
approved RSP and as modified by FERC’s February 1 SPD (collectively referred to herein as the
“Study Plan”).
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 in the Middle
and Upper Susitna River in proportion to their species-specific abundance. Capture
and tag Chinook, coho, and pink O. gorbuscha salmon in the Lower Susitna River.
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2) Characterize the migration behavior and spawning locations of radio-tagged salmon
in the Lower, Middle, and Upper Susitna River.
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 encompasses the Susitna River from Cook
Inlet upstream to the Oshetna River, or as far upstream as Chinook salmon are detected (Figure
3-1), with an emphasis on wherever salmon spawn 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 are: 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 [2013] for more detail on the impediments).
4. METHODS
Descriptions of the study methods are organized below by objective. This is a multi-year study
initiated in 2012. The methods below refer to research conducted in 2013 and planned for a next
year of 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.
AEA implemented the methods with respect to Objective 1 as described in the Study Plan with
the exception of variances explained below (Section 4.1.8). Tasks to address Objective 1 were
listed in RSP Section 9.7.4.1.
4.1.1. Fish Capture
In the Lower River, two fishwheels and gillnets were used to capture adult salmon for tagging in
2013. The fishwheels were operated at locations that were fished in 2010–2012 (Figure 3-1).
One fishwheel operated on the west bank of the Lower River at PRM 33.4 for 1,061 hours from
June 3 to August 31, and the second fishwheel operated on the east bank at PRM 34.2 for 1,050
hours from June 3 to August 31 (Figure A-1). From June 3 to July 2, gillnets were fished in the
vicinity of the fishwheels for a total of 39.6 hours (Figure A-2). The gillnets were 5.5 inch (in;
stretch) or 7.5 in mesh, multi-strand web, 50–150 feet (ft) long, and 60 meshes deep. Seventeen
percent of the effort was with 7.5-in mesh and 83 percent with 5.5-in mesh.
In addition, two fishwheels and gillnets were used on the lower Yentna River, and in the same
locations as had been operated for three decades (Figures 3-1). One fishwheel operated on the
south bank of the Yentna River (river mile 6) for 167 hours June 3–30, and the second fishwheel
operated on the north bank of the Yentna River (RM 6) for 166 hours June 2–29 (Figure A-3).
There was effort for both fishwheels every day in 2013, and both fishwheels achieved the
targeted effort (12 hours/day) on nearly every day. From June 3 to 22, gillnets (5.5 and 7.5-in
mesh) were fished in the vicinity of the fishwheels for a total of 74.1 hours (effort was split
equally between mesh sizes; Figure A-4).
In the Middle River, three fishwheels and a beach seine were used to capture adult salmon for
tagging in 2013. Two of the fishwheels were operated at the same two locations used in 1981–
1985 and in 2012 (sites 1 and 2; Figures 3-1 and 4.1-1). From June 9 to September 17, one
fishwheel operated for 1,167 hours (48.5 percent of the time it was in place) on the west bank of
the Susitna River at Site 1 (PRM 124.1; Figure A-5). Excluding the days it did not operate, daily
fishing effort at Site 1 averaged 13.6 hours (range: 5.1–24 hours). The targeted amount of daily
fishing effort at Site 1 varied by period: 18 hours from June 9 to 27 and July 4 to 22; 24 hours
from June 28 to July 3; 10–12 hours from July 23 to August 22; and 9 hours from August 23 to
September 17. The Site 1 fishwheel did not operate during high water and heavy debris loads
(August 22–23), or during low-water periods (July 18–22, August 9–11, August 18, and after
September 17).
From June 13 to September 16, the second fishwheel operated for 1,150 hours (50.4 percent of
the time it was in place) on the east bank of the river at Site 2 (PRM 123.0; Figure A-5). Daily
fishing effort averaged 12.5 hours (range: 4.5–18.4 hours). Targeted daily fishing effort varied at
Site 2: 18 hours from June 13 to 27 and July 4 to 16; 13–14 hours from June 28 to July 3; 12
hours from July 17 to August 21; and 9 hours from August 24 to September 16. The Site 2
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fishwheel did not operate during high water and heavy debris loads (July 19, July 22, and
August 22–23).
A third fishwheel was operated from July 17 to September 30 (550 hours of effort; 30.6 percent
of the time it was in place) at a new site in 2013 (Site 3), which was located on the west bank of
the Susitna River at PRM 126.0 (Figure A-5). Daily fishing effort averaged 10.2 hours (range:
2.2–12.5 hours). Targeted daily fishing effort varied at Site 3: 12 hours from July 18 to August 4
and August 8 to 20; 8 hours from August 5 to 7; and 9–10 hours from August 28 to September
30. The Site 3 fishwheel was not operational during high water (August 22–26, August 30–31,
and September 2–16).
On September 25, two sets were made using a beach seine (80 ft long, 7 ft deep, 0.75-in mesh) at
the mouth of Fourth of July Creek targeting adult coho salmon for radio-tagging.
The Middle River fishwheels consisted of 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 fishwheels and the adjacent
riverbank to direct fish away from the bank and into the path of the fishwheel baskets.
Fishwheels were operated 8–24 hours per day. A two-person crew staffed the fishwheels during
operations; when the crew was absent from the fishwheel for more than one hour, the fishwheel
baskets were raised from the water and stopped. Fishwheels operated in the Lower River were
of similar construction, operated in a similar manner, and were staffed at all times during
operation (Yanusz et al. 2011).
4.1.2. Radio-tagging
Pulse-coded, extended-range tags by Advanced Telemetry Systems, Inc., (ATS;
www.atstrack.com) were applied to a subset of salmon captured in the Lower and Middle rivers.
There were 100 unique codes on each available frequency. Model F1835B transmitters were
used for pink salmon (16 grams [g; 0.6 ounces (oz)], 30 cm [11.8 in] antenna, 96-day battery
life); Model F1840B tags for chum, coho, and sockeye salmon (22 g [0.8 oz], 30 cm [11.8 in]
antenna, 127-day battery life); and Model F1845B tags for Chinook salmon (26 g [0.9 oz], 41 cm
[16.1 in] antenna, 162-day battery life). 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 mid-eye to fork (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. Unless otherwise noted, all subsequent
references to adult salmon sizes refer to METF lengths. All fish to be tagged were placed in a
water-filled cooler. 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
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centimeter), and Chinook and coho salmon only were tissue sampled (axillary process) for
genetic baselines (see Section 4.7).
In the Middle River, only uninjured adult fish that met or exceeded a specific length threshold
were radio-tagged, including: large Chinook measuring 50 cm (19.7 in) or greater in length;
Chinook measuring 30–49 cm (11.8–19.3 in) in length (herein referred to as ‘small’); and chum,
coho, pink, and sockeye salmon measuring 40 cm (15.7 in) or greater in length. All fish to be
tagged were placed in a water-filled, foam-lined, V-shaped trough. To minimize handling time
(i.e., achieve less than 2 minutes per fish) and tagging-related effects on fish behavior, anesthetic
was not used. Radio tags were inserted orally into the stomach of the fish 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
sexed based on external morphological characteristics (coloration, body and fin shape, jaw
morphology). All radio-tagged Chinook salmon (small and large) captured at the Middle River
fishwheels were marked with a blue spaghetti tag to assess tag loss, evaluate the effects of
spaghetti-tagging on post-handling behavior and final spawning destination, and provide an
external mark for anglers to recognize fish that had a radio tag. Half of the radio-tagged
Chinook, coho, and sockeye salmon were sampled for scales (to age), and all radio-tagged
salmon were tissue sampled (axillary process) for genetic baselines (see Section 4.7). To
minimize any effects from fish holding, salmon were typically tagged immediately upon capture.
All fish were released immediately after tagging. All fish captured were inspected for radio and
spaghetti tags.
4.1.3. Spaghetti-tagging
In the Middle River, spaghetti-tagging was used to augment the ability to test assumptions about
the representativeness of fish captured in the fishwheels. The fishwheels captured more fish of
some species than were needed for radio-tagging alone, and additional marking of these fish
provided more information to test assumptions about how representative the captured fish were
of the population of fish passing fishwheel sites than the radio tags alone. A portion of these
additional fish captured were spaghetti-tagged, and this portion varied among species according
to availability of fish above radio-tagging goals and the opportunities available for examining
fish subsequent to the tagging event.
Based on 2012 fishwheel catches at Curry, it was anticipated that a large number of chum
salmon, a limited number of Chinook and sockeye salmon, and few to no coho salmon above
those needed to meet daily radio-tagging goals would be available for spaghetti-tagging in 2013.
It was also expected that an insufficient number of pink salmon could be spaghetti-tagged in
order to develop defensible mark-rate estimates since it was an “off-peak” year. Unexpectedly, a
large number of chum, coho, and pink salmon were available for spaghetti-tagging, so tags were
implanted and fish were released.
4.1.4. Daily Tagging Goals
Recent (2012) and historical (1981–1985) fishwheel catches, effectiveness, and salmon run
timing guided tag application rates over the season. For the Lower River, the study team met or
came close to the majority of the species-specific, 2013 tagging goals. For Chinook salmon the
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goal was to radio-tag 300 fish per fishwheel; numbers tagged were 385 salmon from the west
bank fishwheel, and 195 from the east bank fishwheel (Table A-1; Figure A-6). The goal for
gillnetting was 100 Chinook salmon, and 118 salmon were actually radio-tagged. For coho
salmon at the Lower River site, the goal was to radio-tag 300 fish per fishwheel; actually tagged
numbers were 343 coho salmon from the west bank fishwheel, and 253 from the east bank
fishwheel (Table A-1; Figure A-6). The difference was the result of re-apportioning radio tags
inseason according to catches. The number of pink salmon tagged was similar to the tagging
goal of 100 fish per fishwheel, with 99 radio-tagged from the west bank fishwheel, and 98 from
the east bank fishwheel (Table A-1; Figure A-6).
The tagging goals for the Yentna River fishwheels were not met in 2013; however, the goal for
tagging fish captured by gillnet was exceeded, so overall goal of tagging 700 Chinook salmon
was almost met. The goal for radio-tagging Chinook salmon was 300 fish per fishwheel; instead,
145 fish were radio-tagged in the north bank fishwheel, and 278 in the east bank fishwheel
(Table A-2; Figure A-7). The goal for gillnetting was 100 fish, while 267 fish were actually
radio-tagged. Consistently low catches in both fishwheels, especially the north bank fishwheel,
led to re-apportioning the radio tags in-season.
In the Middle River, the revised goal of this study was to radio-tag 560 large Chinook salmon
(from an initial goal of 400) and, as outlined in the Study Plan, 200 each of chum, coho, pink,
and sockeye salmon. As was done in 2012, the early season radio-tagging rates of fish captured
in the fishwheels were developed prior to the season, and were based on average historical run
timing and expected daily fishwheel catches at Curry. These initial radio-tagging rates were
adjusted in-season using run-timing information from the fishwheels in the Lower River, and the
ratio of current year’s daily catch at Curry to the expected daily fishwheel catch based on
historical data. All species-specific goals were met with the exception of sockeye salmon.
Final 2013 radio-tagging numbers in the Middle River were 603 Chinook (536 large, 67 small),
201 chum, 242 coho, 200 pink, and 139 sockeye salmon (Table A-3; Figure A-8).
4.1.5. Numbers and Size of Marked and Unmarked Fish at Selected Locations
4.1.5.1. Lower River and Yentna River
The primary goal of radio-tagging Chinook salmon in the Lower River and Yentna River was to
estimate their system-wide abundance. This goal and tests of underlying assumptions are
addressed under Objective 8 in Section 4.8.
4.1.5.2. Middle River
To test if Chinook, chum, pink, and sockeye salmon passing the fishwheels were equally
vulnerable to being captured and radio-tagged, fish were examined in a tributary stream (i.e.,
Indian River) to develop two primary metrics: estimates of the proportion of fish tagged (mark
rate), and the size distributions of tagged and untagged fish.
From June 26 to August 20, 2013, a picket weir was operated on the lower Indian River,
approximately 1.6 river miles from the confluence with the Susitna River (Figure 3-1), to free-
pass upstream and downstream moving adult fish past underwater video cameras. The weir was
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located far enough upstream to minimize the number of fish milling at the weir, yet far enough
downstream to ensure the majority of fish returning to the river would be available to count
passing through the video chute.
The underwater video system at the weir was operated 24 hours a day, and collected 1,300 hours
of video footage from June 26 to August 20 (Figure B-1). Two high-water events occurred
during the operational period of the weir. During the first high-water event from July 19 (9:31
P.M.) to July 20 (3:26 P.M.), the video-recording equipment was temporarily removed from the
chute for approximately 18 hours. The second high-water event occurred August 19–25; and on
August 20 (12:00 P.M.) all video-recording equipment was permanently removed and weir
operations ended for the season. Of the video imagery collected, 981 hours (75.5 percent) was
reviewed in full (including all video obtained during the Chinook salmon run) and 319 hours
(24.5 percent) was sub-sampled (15 minutes per hour; Figure B-1). Full review (24 hours/day)
of video imagery for each hour was performed June 26 through August 1. From August 2 to 20,
full review was performed from 0:00–1:00 A.M. and 8:00 P.M. to midnight, at a minimum, for
each calendar day. For sub-sampled periods, species-specific counts were expanded (i.e.,
multiplied by four) to estimate the total count for each hour. For each salmon that passed
through the chute, crews recorded the date/time, species, direction of travel (upstream,
downstream), sex, fork length (FL; in cm), and whether a radio or spaghetti tag was observed.
All fork lengths were converted to mid-eye to fork lengths using species-specific regression
equations derived at Curry in 2012 (see Table 3 in AEA [2013]). The net upstream count of all
salmon (by species) was estimated, and counts were made of all other fish species at the weir.
Net passage of fish at the weir, by species, was determined by subtracting the total number of
downstream-moving fish (tagged and untagged) from the total number of upstream-moving fish.
A positive number indicated a net upstream movement of fish and a negative number indicated a
net downstream movement of fish. Accounting for the direction of fish movement reduced the
potential for bias when individuals moved back and forth through the video chute, in some cases
repeatedly; as all five salmon species (as well as other fish species) milled in the vicinity of the
weir. Species-specific mark rates were estimated by dividing the net numbers of marked fish
estimated to have passed the weir by the total number of fish counted through the chute on the
video imagery. The numbers of passing chum, coho, and pink salmon that were spaghetti-tagged
in the Middle River were estimated from fish inspected for tags on the video imagery. The
numbers of passing fish that were radio-tagged in the Middle River were estimated from
detections at a fixed-station receiver site located at the weir, and from aerial telemetry surveys.
Radio-tagged chum, coho, pink, and sockeye salmon did not receive a spaghetti tag at the Middle
River fishwheels, so video imagery was not a reliable method for identifying radio-tagged fish
(radio-tag antennas were difficult to see protruding from the mouth).
Aerial spawner surveys were also used to count live and dead fish. Combined with fixed-station
and aerial telemetry data, these provided a second set of counts of marked and unmarked fish in
Indian River.
4.1.6. Examining Handling-Induced Changes in Behavior
An assumption of this study is that the behavior of radio-tagged fish was not materially affected
by the capture and handling process. By materially affected, AEA means that the capture and
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tagging did not affect the final spawning destination of a fish and/or its migration behavior once
it had recovered from the tagging event and resumed its migration. If (and when) sufficient
genetic structure can be found among stocks of various species in the Susitna River, genetics
could offer a reasonably good test of whether handling may have influenced the final destination
of tagged fish. Until then, this assumption cannot be tested directly, but there are several indirect
ways to assess the potential for handling effect.
As stated in RSP Section 9.7.4.1.6, potential handling affects were evaluated based on the
survival and travel time of tagged fish, tag mark rates at spawning location, and the post-release
migratory behavior of tagged fish recaptured in fishwheels.
Note that a potential handling effect will not pose an analysis issue if the effect is binomial in
nature, i.e., simply a significant “on” or “off” with any individual fish. The study design allowed
for some fish dropping back and not resuming their upstream migration, by removing these fish
from the experiment and subsequent analyses. The potential handling effects would be of issue
if the effects were more subtle and went undetected but materially affected fish behavior.
4.1.7. Assessing Any Stock- and Size-selective Capture
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. The assumption of equal
probability of capture across fish from all spawning destinations was tested indirectly by
examining several sources of information. If there were unequal probabilities of capture among
spawning stocks, it would be caused by, and manifest itself, in multiple ways. These issues were
addressed for fish tagged at the Lower and Middle River sites.
4.1.7.1. Lower River
The assumption that radio-tagged salmon represent the population of salmon passing the tagging
site was evaluated for Chinook and coho salmon tagged at the Lower River site in the framework
of the mark-recapture experimental design. Heterogeneity in probability of capture was
investigated by fish size (length MEF), 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 Cleary et al. (2013). These tests have not yet been performed for
Chinook salmon radio-tagged in the Yentna River because length and date of passage data from
the Talachulitna River ARIS sonar site were not available in time to be included in this ISR.
The evaluations of the assumption of equal probability of capture and radio-tagging for all
Chinook or coho salmon passing the lower mainstem tagging site are based on characteristics of
all fish counted passing the Montana Creek and Deshka River weirs and of all marked fish
“recaptured” at these weirs. Independent tests are performed for data from each weir site to
evaluate equal probability of capture by size and temporally, while spatial tests require the data
from both weirs.
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4.1.7.1.1. Equal Probability of Capture by Size
Equal probability of capture by size was evaluated using the Kolmogorov-Smirnov (KS) two-
sample test. This test determines if the distribution of lengths from all fish passing a weir site are
similar to recaptured (radio-tagged) fish passing the weir site. Under the null hypothesis, the
probability that a fish is radio-tagged is independent of the size of the fish, and the cumulative
distribution function of the lengths of all fish passing a weir site are expected to be similar to the
function of all recaptured fish passing that weir site. A significant test statistic from the KS test
provides evidence for rejecting the null hypothesis in favor of the alternative that the probability
that a fish was tagged was related to fish size.
4.1.7.1.2. Equal Probability of Capture Over Time
Equal probability of capture over time was evaluated using contingency table analysis with the
χ2 test for independence. For a weir site, the observations of numbers of fish passing the weir by
day and number of recaptures passing the weir by day are 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 contains the number of recaptured fish and the second contains the number of unmarked fish
accounted for in the time period. Under the null hypothesis that the probability that a fish is
radio-tagged is independent of when it passed the tagging site, it is expected that the marked-
unmarked ratios of fish observed at each weir site are independent of time. This analysis
determines if the ratio of marked-unmarked fish observed at each weir site is independent of
time. A significant test statistic from the χ2 test provides evidence for rejecting the null
hypothesis in favor of the alternative that the probability that a fish was tagged was related to
when it passed the tagging site.
4.1.7.1.3. Spatial Variation in Probability of Capture
Spatial variation in probability of capture was also evaluated using contingency table analysis,
using a 2x2 table containing the numbers of marked and unmarked fish observed at each of the 2
weir sites. This analysis determines if the marked-unmarked ratios of fish observed at each weir
site are similar. If they are similar then the probability of tagging is independent of which
tagging site (east or west bank (fishwheels) or midstream (gillnet sites) it passes. Under the null
hypothesis that the probability that a fish is radio-tagged is independent of whether it passes the
tagging site near the east or west banks (fishwheel sites) or nearer midstream (gillnet sites), it is
expected that the marked-unmarked ratios of fish observed at each weir site are similar. A
significant test statistic from the χ2 test provides evidence for rejecting the null hypothesis in
favor of the alternative that the probability that a fish was tagged was related where or possibly
when it passed the mainstem Susitna tagging site. Evaluation of a significant test statistic for this
test requires consideration of both temporal and geographic variation in probability of capture, as
a significant statistic could be a function of travel times from the tagging site to the weir site, as
well as bank orientation of the salmon at the tagging site.
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4.1.7.2. Middle River
4.1.7.2.1. Fishwheel effectiveness across time
The main assumption of this study component is 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, from a ratio of the number of fish caught to the number of fish observed. 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 7 to September 30, one ARIS unit operated 24 hours per day on the right
bank of the Susitna River. The unit was located immediately downstream of the Site 1 fishwheel
(Figure 4.1-1; Figure A-9). Daily review effort for Unit 1 varied over the season, and ranged
from 24 hours per day (J une 7–26), every second day (June 27 to July 12, and September 1–30),
to no review effort (July 13 to August 29). A second ARIS unit was installed to sample fish
migrating farther offshore. Unit 2 was operated from September 12 to 30, with 100 percent
review effort (Figure A-9). The sonar sampling area was 0.67–10.7 meters (m; 2.2–35.1 ft) for
Unit 1, and 9.2–24.9 m (30.2–81.7 ft) for Unit 2, which provided a 1.5 m (4.9 ft) overlap in
coverage between the units.
The catch-per-unit-effort (CPUE; fish per fishwheel hour) for each fishwheel over time and
across a range of discharges was also evaluated.
4.1.7.2.2. 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 to
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 to other tagged fish to determine whether fish that spawned in the
mainstem were recaptured at a higher rate.
Size-related selectivity was tested using (KS) two-sample tests. For each species, comparisons
included the cumulative length-frequency distributions of (1) radio-tagged and spaghetti-tagged
fish and those fish randomly sampled at the Indian River weir; (2) radio-tagged and spaghetti-
tagged fish and all other fish sampled for length at the Middle River fishwheels; and (3) radio-
tagged and spaghetti-tagged fish captured in individual fishwheels.
4.1.8. Variances
4.1.8.1. Fish Capture
RSP Section 9.7.4.1 indicated that, if feasible, AEA would operate a fishwheel in Devils Canyon
below the impediments from late June through late July in 2013 to supplement the Middle River
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fishing effort for Chinook salmon. The purpose of this recommendation was to explore whether
it was possible to increase the sample size of radio-tagged Chinook salmon moving into and
above Devils Canyon. However, land-access limitations precluded siting a fishwheel in Devils
Canyon in 2013. Once it was determined that land access would not be available, AEA
developed an alternative to increase the numbers of tagged fish in Devils Canyon, subject to the
availability of additional tags from the tag vendor. Specifically, AEA increased the tag goal
from 400 to 560 fish, and increased daily fishing effort at the fishwheels located near Curry
(from a maximum of 12 hours/day to as high as 24 hours/day). This variance did not affect
achieving study Objective 1.
RSP Section 9.7.4.1 indicated that two fishwheels would be used at Curry, in a similar fashion to
what was done in 2012. AEA began the season with two fishwheels at the same sites as in 2012,
and in July deployed a third fishwheel. This was needed due to changes in the river channel that
occurred following the 2012 field season which made water velocities slower at the right bank
fishwheel site (PRM 124); considerable effort was required to keep this fishwheel operating
effectively, particularly during low water. A new third site was found (Site 3, right bank, PRM
126) that was more effective at lower discharges. Fishing began at Site 3 on July 17. This
variance increased the likelihood of achieving Objective 1. AEA plans to operate a third
fishwheel for the next year of study.
4.1.8.2. Radio-tagging
RSP Section 9.7.4.1.2 indicated that only large Chinook salmon would be radio-tagged in 2013.
However, 536 large and 67 small Chinook salmon were radio-tagged. By late June, it became
apparent that small Chinook salmon comprised a substantial portion of the total Chinook salmon
catch in 2013, and the revised radio tag target for large Chinook salmon (560) might not be met.
Given that small Chinook salmon behavior could help characterize spawning locations, it was
deemed worthwhile to apply some tags to this segment of the population. Subsequently, all
available large Chinook salmon were tagged while a sub-sample of small fish were tagged. All
subsequent analyses stratified results by these two size groups, and therefore this did not bias
results. This variance did not affect achieving study Objective 1. AEA plans to radio-tag small
Chinook salmon again in the next year of study to ensure that all sizes are represented.
4.1.8.3. Assessing Any Stock- and Size-selective Capture
RSP Section 9.7.4.1.5 indicated that Chinook, sockeye, and chum salmon would be examined on
selected spawning grounds to test whether fish were equally vulnerable to being captured and
radio-tagged. However, results from spawning ground surveys in 2012 indicated that it was
going to be difficult to achieve useful sample sizes from surveying spawning grounds on foot
and from the water. Therefore, AEA determined that a floating picket weir and underwater
video system on the lower Indian River would be a more effective means of examining a large
number of fish in 2013. The same two metrics (i.e., mark rate and size distribution of
tagged/untagged fish) were developed from fish counts at the weir that would have been
developed from spawning ground surveys. In addition, the weir allowed development of these
metrics for pink salmon. This variance increased the likelihood of AEA achieving study
Objective 1. AEA plans to operate the Indian River weir again in the next year of study.
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In RSP Section 9.7.4.1.6, AEA indicated that the upstream movements of tagged fish that were
subjected to different holding densities and times in the fishwheels would be compared.
However, crews continuously monitored the fishwheels while they were operated and tagged
individual fish soon after they were captured. This resulted in brief holding times, generally less
than 25 minutes, and consistently low densities of fish in holding tanks. Due to the similarity of
holding conditions for all tagged fish, a comparison of post-release survival and migration
behavior was determined to be unnecessary in 2013. This variance did not affect achieving study
Objective 1. AEA plans to use the same approach for the next year of study.
RSP Section 9.7.4.1.7 indicated that the sex and age composition of radio-tagged fish would be
used to assess fishwheel selectivity in 2013. Early on 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; therefore, these comparisons were not attempted.
Results of scale analyses to determine fish ages were not available at the time this report was
prepared. In light of the fact that size selectivity was tested in 2013, and that fish were randomly
selected for tagging, this variance should not affect achieving study Objective 1. AEA plans to
use the same approach for the next year of study.
4.2. Objective 2: Determine the migration behavior and spawning
locations of radio-tagged fish in the Lower, Middle, and Upper
Susitna River
AEA implemented the methods with respect to Objective 2 as described in the Study Plan with
the exception of variances explained 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 (aerial, boat, and foot) 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 provided 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
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• 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 deltas) and tributaries. In addition, observed spawning locations were
characterized at a microhabitat level (e.g., depth, velocity, and substrate). 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 fates of individual tagged fish. Additional methods pertaining to the
set-up and operation of fixed-station receiver sites were provided in RSP Section 9.7.4.2.1.
Figure 3-1 shows the locations of the fixed stations in the Lower, Middle, and Upper River.
Twelve fixed-station receiver sites operated in the Lower River in 2013, and 11 fixed-station
receiver sites were operated in the Middle and Upper rivers (Tables C-1 to C-3). Locations of
the fixed stations in the Middle and Upper rivers are listed below. The fixed stations at Lane
Creek and the Upper Indian River were operated with two receivers (Table C-1).
1. Whiskers Creek (PRM 105.1)
2. Lane Creek area (PRM 116.7)
3. Middle River Gateway (PRM 130.1)
4. Fourth of July Creek (PRM 134.3)
5. Indian River confluence (PRM 142.0)
6. Indian River Weir (RM 1.6 on the Indian River)
7. Powerline (PRM 145.7)
8. Devils Island (PRM 166.9)
9. Deadman Creek (PRM 191.2)
10. Kosina Creek confluence (PRM 209.2)
11. Oshetna River (PRM 235.1)
The Lower River fixed stations were chosen to represent significant tributaries that were known
to contain Chinook salmon. The 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 through the Upper River to quantify passage through
Devils Canyon. See Section 4.3 for additional details about the telemetric monitoring in Devils
Canyon (Objective 3).
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4.2.2. Aerial Telemetry Surveys
Aerial telemetry surveys of the mainstem Susitna were conducted from the mouth of the Yentna
River (PRM 31.4) to PRM 307. Surveys were conducted by helicopter to allow relatively
accurate positioning of tagged fish and to locate spawning areas, all with respect to mainstem
habitat typing completed by Habitat Mapping, Study 9.9. The 2013 surveys began on June 22
and ended in late October (see Table C-4 for a summary of the surveys conducted). Survey
timing was adjusted depending on the observed fishwheel catches in the Lower and Middle
River. Surveys were scheduled to cover each section of the river (Lower, Middle, and Upper)
each week. Once adult salmon were observed entering Devils Canyon, the Susitna River and its
tributaries from Portage Creek to Devils Island were flown daily. Daily flights continued until
upstream movement in Devils Canyon had stopped. During the peak chum and sockeye salmon
migration and spawning periods in the Middle River, the stretch from the mouth of the Chulitna
River to Devils Island was surveyed twice per week to monitor the movements of salmon into
spawning locations.
Helicopter surveys were conducted at lower elevations 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. The spatial resolution of helicopter surveys was
approximately 300 m (1,000 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. Geographic coordinates were recorded for each signal detected using an
integrated communication link between the telemetry receiver and a global positioning system
(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.
The mainstem aerial telemetry surveys covered over 200 river miles (Yentna River mouth to the
Oshetna River and occasionally beyond), 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 laptop computer
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.
When aggregations of two or more tagged fish were found “stationary” (i.e., within 2 kilometers
[km; 1.2 miles (mi)] on one or more surveys) or when visual observations of spawning fish were
made from the helicopter-, ground-, or boat-based surveys, spawning locations were more
intensely tracked to achieve relatively high-resolution geographic positions. This protocol was
particularly important for ensuring coverage of any suspected Lower River habitats with the
appropriate level of spatial resolution.
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The habitat type (mainstem, side channel, or slough) and relative water turbidity was classified
for each tag detected (time stamp, frequency, code, and power level). If other fish were seen in
the area of the tag position, their relative abundance was noted to provide context for the tag
observation.
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
provided to the habitat sampling team (Study 9.9) and Instream Flow Study (Study 8.5) to inform
their field sampling efforts.
In 2013, fixed-wing surveys of tributary systems of the Susitna and Yenta rivers were conducted
by ADF&G, from approximately PRM 23 to Devils Canyon and in the upper Chulitna River, at
7–10 day intervals from June 24 through September. These surveys provided fish locations to
the nearest river mile and helped to characterize the fates of fish tagged in the Lower and Middle
River. Although these 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. All tag
frequencies for Chinook salmon released in the Lower and Middle River were scanned during
surveys from June 24 to August 12. Tag frequencies for all coho salmon released were scanned
during fixed-wing surveys on August 4 and later. Tag frequencies for chum, pink, and sockeye
salmon released in the Middle River were not scanned during the fixed-wing surveys.
4.2.2.1. Lower River Surveys
Helicopter surveys of the Lower River covered mainstem areas from the mouth of the Yentna
River (PRM 31.4) to the confluence of the Chulitna River (PRM 102.4). This reach was highly
braided with side channels and sloughs, so complete coverage required considerable effort and
in-flight route tracking.
4.2.2.2. Middle River Surveys
Helicopter surveys of the Middle River 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); this reach required approximately one day to complete. The river between Devils Island
(PRM 166.9) and the proposed Watana Dam site was usually flown during surveys of the Upper
River.
4.2.2.3. Upper River Surveys
Helicopter telemetry surveys of the Upper River generally were triggered by detection of fish
moving above the Devil Creek fixed station. Upper River telemetry surveys covered the
mainstem areas from the proposed Watana Dam site (PRM 187.1) to the Oshetna River (PRM
235.1). This reach included approximately 48 relatively confined river miles. This survey
required approximately one survey day; less when done in conjunction with Middle River
surveys (i.e., when less conveyance time was involved). Radio-tagged fish above Devils Canyon
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were located at a spatial resolution in habitat types similar to the Middle and Lower river
surveys.
4.2.3. Boat and Ground Surveys
In support of Study 8.5 (RSP Section 8.5.4.5.1.1), telemetry surveys were also conducted by boat
and on foot to obtain the most accurate and highest resolution positions of holding and spawning
fish. Boat surveys were limited to the Susitna River mainstem. The resolution of these positions
was within 5–10 m (16–32 ft) in turbid water and 2–3 m (6.5–10 ft) in clear water. A hand-held
three-element Yagi antenna and judicious use of the signal gain control on the ATS receiver
enabled radio-tagged fish to be located and GPS coordinates were recorded for each fish. These
surveys were conducted opportunistically from July through September.
4.2.4. Variances
Five of the fixed stations listed in RSP Section 9.7.4.2.1 were not used in 2013. CIRWG land
access limitations precluded siting three of these stations (Portage, Cheechako, Chinook creeks);
and the remaining two stations (Slough 11 and Slough 21) were sited elsewhere in the Middle
River, where a larger number of tags would be detected (relative to the 2012 study). New fixed
stations in 2013 (i.e., sites not used in 2012) that were not listed in RSP Section 9.7.4.2.1
included Whiskers Creek (PRM 105.1), Fourth of July Creek (PRM 134.3), Indian River Weir
(RM 1.6 on the Indian River), and Powerline (PRM 145.7) in the Middle River; and Deadman
Creek (PRM 191.2) and Oshetna River (PRM 235.1) in the Upper River.
To address the lack of fixed stations at Portage, Cheechako, and Chinook creeks, AEA installed
the Powerline station at PRM 145.7. This station was on the mainstem Susitna and provided
monitoring to characterize the movement of fish into the area between Portage Creek and Devils
Canyon. This provided an inventory of all tags in that area for aerial and boat-based surveys.
The study team also flew aerial telemetry surveys daily, and at times twice daily, to monitor fish
passage through Devils Canyon (Table C-4). In the end, these frequent aerial surveys provided
more detailed information on geographic movements and holding periods below impediments
than would have been provided by the previously proposed three fixed stations alone. Devils
Canyon spans approximately 11 river miles (PRM 153.7–164.8). Fixed stations provide
information only when the fish is near the station, whereas daily aerial telemetry surveys were
able to locate tagged fish and characterize fine-scale movements within Devils Canyon and
adjacent tributaries. The fixed station at Devil Island (PRM 166.9) was able to monitor for any
tagged fish that may have moved above the third impediment; therefore, there was no gap in the
study team’s understanding of the daily positions of tagged fish while in Devils Canyon. As a
result, these variances enhanced AEA’s ability to achieve study Objective 2.
4.3. Objective 3: Characterize adult salmon migration behavior and
timing within and above Devils Canyon
AEA implemented the methods with respect to Objective 3 as described in the Study Plan with
the exception of variances explained below (Section 4.3.5). Tasks to address Objective 3 were
listed in RSP Section 9.7.4.3.
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4.3.1. Fixed-station Monitoring
A combination of aerial telemetry surveys and fixed stations above and below (e.g., Powerline
Station) Devils Canyon was used to determine the migration timing and behavior of radio-tagged
salmon that passed into the Upper River (Figure 3-1). Fixed stations were deployed at locations
where they had the highest probability of detecting radio-tagged salmon (within permitted areas).
The fixed stations deployed at the confluences with Kosina Creek and Oshetna River provided
additional information that was used to assess the detection efficiencies for all mainstem fixed
stations downstream from these sites. The data from these fixed stations was also used to guide
the aerial and ground-based survey efforts needed to identify spawning areas in the Upper River.
4.3.2. Aerial Telemetry Surveys
The mobile-telemetry survey data aided in confirming the presence of radio-tagged fish, and
locating any tagged fish not detected at downstream fixed-station sites. These additional
detections were combined with the aerial-survey data to estimate detection efficiencies for each
fixed station. The timing and proportion of all tagged salmon that passed Devils Canyon was
calculated and compared to the remaining tagged population, and their final spawning locations
were identified.
4.3.3. Aerial Spawner Surveys
Aerial visual-observation surveys to determine the distribution and relative abundance of adult
salmon were conducted in the Susitna River and its tributaries within and above Devils Canyon,
upstream to and including the Oshetna River. A total of five aerial spawner survey events were
conducted at approximate weekly intervals from July 19 through August 16, 2013 (Table 4.3-1).
The survey extent covered major tributaries and clear water areas of the Susitna River from
Cheechako Creek to the Oshetna River. A total of 19 streams were surveyed during each of the
five events; 13 tributaries to the Susitna River and six secondary tributaries (Table 4.3-1).
Additionally, two lake systems in the Tsisi Creek drainage were surveyed during August
specifically to look for spawning sockeye salmon. All streams were surveyed from their
confluence up to 3,000 feet in elevation, or to a predetermined barrier to anadromous fish
passage, or to the stream’s headwater origin, whichever came first (Figure 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)
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, through comparison with
concurrent weir counts.
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4.3.4. Assess the Feasibility of Using Sonar to Enumerate Salmon and
Resident Fish at the Proposed Dam Site
The FERC SPD 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. Prior to the 2013 field season, operation of a weir near the dam site was
determined to be not feasible (see Appendix G for further details). However, AEA assessed the
feasibility of placing a sonar counting station at or near the dam site. This effort involved sonar
surveys at three potential sites between PRM 184 and PRM 188. The feasibility study is
provided in Appendix G.
4.3.5. Variances
Lack of permission to access CIRWG land precluded siting fixed stations within Devils Canyon
as described in RSP Section 9.7.4.3. To compensate for the absence of fixed stations within
Devils Canyon and to ensure that the study objectives were achieved, helicopter surveys for
tagged fish were flown through Devils Canyon daily starting in late June, and twice daily during
the period of Chinook salmon passage (Table C-4). Daily surveys were attempted in and
upstream of Devils Canyon and as long as there were fish above the first impediment. Section
4.2.4 provides additional information on the benefits of these additional aerial telemetry surveys.
This variance did not affect achieving study Objective 3.
4.4. Objective 4: Use available technology to document salmon
spawning locations in turbid water
AEA implemented the methods with respect to Objective 4 as described in the Study Plan with
the exception of variances explained below (Section 4.4.3). In 2013, ARIS was used to examine
the feasibility of sampling turbid water to quantify spawning activity in mainstem habitats of the
Susitna River.
From July 24 to 31, 2013, 15 potential Chinook salmon spawning sites were visited (Table 4.4-1)
and eight were surveyed using ARIS. Salmon were observed at seven sites, however, spawning
activity (nest-guarding behavior) by Chinook salmon was only observed at one site (Indian River
Delta). At many sites, the presence of chum salmon made identification of Chinook salmon in
the sonar image difficult. Several potential spawning sites could not be accessed via boat and
other sites had physical characteristics not suitable for salmon spawning (e.g., high water
velocity, thalwag of the river, or rapids).
On July 31 and August 12, two potential spawning sites for chum salmon were sampled using
ARIS (Table 4.4-2). Chum salmon were observed at both sites, but spawning was only
confirmed at one site. Confirmation of spawning, observed with ARIS, included nest-guarding
behavior and visible redds.
Additional site-specific information was collected and subsequently relayed to the Fish and
Aquatics Instream Flow Study (Study 8.5) team (Tables D-1 to D-6).
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4.4.1. Sonar Equipment and Methods
The sonar system consisted of the ARIS unit, X2 rotator assembly, data transmission cable,
laptop computer loaded with ARISScope data-acquisition software, and portable external hard
drives. The system was powered with a 2,000 watt (W) Honda generator.
Data were acquired using an ARIS unit attached to a dual-axis rotator. The ARIS and rotator
assembly were deployed from a winch-operated pole-mount secured to the gunwale of a jet boat.
The rotator assembly allowed for panning and tilting of the ARIS; and depth was controlled by
using the winch to raise and lower the assembly.
Potential spawning locations were identified from 2012 and 2013 detections of radio-tagged
salmon. At each site, the ARIS was lowered from the side of the boat to approximately 10 cm
(3.9 in) above the substrate along the edge of the river. The boat was slowly walked along the
bank with the ARIS oriented approximately perpendicular to the riverbank. Survey lengths
varied depending on river conditions and the presence of potential spawning habitat. 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.
• 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; e.g., Gateway Slough).
Data were initially collected using 10–20 m (33–66 ft) sample windows. 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 ARIS depth and tilt angle was adjusted as necessary to maximize coverage of the substrate.
When fish were located and spawning behavior activities were suspected, the boat was stopped
and 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.
4.4.2. Sonar Data Analysis and Reporting
Data were collected using a frame rate of eight frames per second in consecutive 10-minute files.
Data were ported directly to external hard drives, and backed up and archived to additional hard
drives after each survey. Locational data were collected during each survey using a hand-held
GPS unit time-synchronized with the ARIS system to allow for geo-referencing locations of
observed spawning activities.
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Data processing involved playing back the streaming data files using ARISFish software. Files
were reviewed to note the following for each survey:
• Presence or absence of redds. If redds were identified, the length and width of each redd
was estimated using the software’s sizing tool. The number of detected redds per square
meter was estimated.
• Presence or absence of adult salmon. When adult salmon-sized fish were detected, total
lengths of individual fish was estimated using the software’s sizing tool. The number of
adult salmon per cubic meter was estimated.
• 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.
4.4.3. Variances
RSP Section 9.7.4.4.2 indicated that side-scan sonar and Dual Frequency Identification Sonar
(DIDSON) would be used for this component of the study; however, an ARIS sonar unit was
used in 2013. Although 2012 side-scan images showed features of the river bathymetry and a
variety of substrate types, no obvious salmon redds were observed and the utility of this method
to identify features not observable with a DIDSON or ARIS sonar was minor at best. Thus, no
side-scan sonar was deployed in 2013. ARIS is a second generation (after DIDSON) imaging
sonar (www.soundmetrics.com) and the main improvement over DIDSON is its flexibility in
setting the sampling window parameters. The size and start range of the sample window can
also be customized to fit optimal sample volume configurations. This provided additional
resolution and characterization of substrate features. ARIS provided all the capabilities of
DIDSON and side-scan sonar for confirming salmon spawning in turbid water. Thus, the
variance of using ARIS in 2013 instead of DIDSON and side-scan sonar did not affect achieving
study objective 4. AEA plans to use ARIS again in the next year of study.
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. A comparison was made of this study’s results from 2012 and 2013 to the
historical results 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 to 1985)
relevant to at least four fishwheel sites along the Susitna River. These abundance estimates were
apportioned to mainstem, sloughs, and tributaries. One weakness of the 1980s studies was that
they 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
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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 and 2013, and by using radio telemetry and sonar
technology not available in the 1980s. Both methods provide 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 are similar to earlier studies, the current study
greatly increased the sample size and confidence in the conclusions from studies in both periods.
Therefore, the explicit comparison and contrast of the distribution and habitat use of salmon in
the Lower, Middle, and Upper river habitats of the Susitna River is valuable.
4.5.1. Variances
No variances from the methods described in the Study Plan occurred during the 2013 study
season.
4.6. Objective 6: Generate counts of adult Chinook salmon
spawning in the Susitna River and its tributaries
AEA implemented the methods with respect to Objective 6 as described in the Study Plan with
the exception of variances explained below (Section 4.6.1). This objective was addressed by
operating weirs on tributaries (see Objective 8) and conducting aerial spawner surveys in Indian
River (see Objective 3) in 2013. The purpose of this work was to establish survey-area mark
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
were used to estimate the abundance of salmon passing the tagging sites, and the abundance of
Chinook salmon passing upstream of Devils Canyon.
Assumptions were made and tested regarding the representativeness of tagging and proportion of
the run detected visually and by telemetry. All aerial spawner survey data was stratified as
‘above’ or ‘below’ the Indian River weir. A combination of aerial- and weir-based counts were
used. Weirs were placed on the Indian River and in selected Lower River tributaries (see
Objective 8). Aerial telemetry surveys by helicopter were conducted in July and August 2013
(Table C-4). Protocols developed based on 2012 experience, were implemented in 2013 to
survey the Portage Creek and Indian River tributaries of the Middle River.
Aerial telemetry survey data were used to establish estimates of minimum and likely numbers of
fish based on a range of observer efficiencies. The estimates were used to establish ranges of
possible species-specific mark rates in 2013. Multiple aerial telemetry surveys were flown
bracketing the peak timing of spawning. Survey aircraft were equipped with telemetry receivers
and GPS to identify positions of radio-tagged fish, and visual observations were used to
document the presence of Pacific salmon. The aerial spawner surveys did not provide a direct
estimate of the total salmon abundance in tributaries. Instead, they provided a minimum count
and then helped to establish minimum and likely tributary-specific mark rates, as was done for
Portage Creek and Indian River tributaries in 2012.
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4.6.1. Variances
Results from the 2012 escapement study indicated that it would be unlikely to obtain sufficient
numbers of fish through spawning ground surveys to address both the original objectives of RSP
Section 9.7.4.6 (mark rates), and the additional goal of estimating the numbers of fish above
Devils Canyon that was established during the FERC Study Dispute process. Therefore, a
decision was made to replace spawning ground surveys with operation of a weir and an
underwater video system on the Indian River to enumerate tagged and untagged fish, and
establish mark rates (see Section 5.6.2). This variance provided more rigorous data and did not
affect achieving study objective 6.
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 objective 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 and from all untagged spawning fish that were sampled during spawning
ground surveys. Sample collections were coordinated with the Genetic Baseline Study team (see
ISR Study 9.14).
Similar to 2012, this study identified the locations of spawning fish and whenever feasible,
collected tissue for use with genetics studies by AEA.
4.7.1. Variances
No variances from the methods described in the Study Plan occurred during the 2013 study
season.
4.8. Objective 8: Estimate the system-wide Chinook and coho
salmon escapement to the Susitna River above Yentna River
and the distribution of those fish among tributaries of the
Susitna River
AEA implemented the methods with respect to Objective 8 as described in the Study Plan with
the exception of variances explained 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. In the Susitna River, the capture event was provided by fishwheels
operated throughout the seasonal salmon migration. Radio tags were applied to fish as close to
proportional of the migrating salmon as possible. Later in the salmon migration, to establish the
proportion of each species that had a tag (also known as the species-specific and stock-specific
mark rate), recaptures were collected from tributary and mainstem weir and sonar sites. Using
relatively simple algebra and making some testable assumptions, a species-specific estimate of
total abundance passing the tagging site was estimated; more specifically, the abundance and in-
river escapement at the fishwheels sites on the Susitna (Chinook and coho salmon) and the
Yentna (Chinook salmon) rivers. Length, sex, and genetics information from the tagged and
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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 June 3 to August 31,
2013, 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 (river mile 6) from June 2 to 30
to capture fish for marking with radio tags (Table A-2; Figures A-3, A-4, and A-7). Lengths of
tagged and untagged fish, and a tissue sample from tagged fish (for genetics sampling), were
collected at each site.
Weirs or sonar on tributaries 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). Fish length was sampled at each site for testing assumptions of the mark-recapture
experiment. At the sonar sites, 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). Fish length samples were attempted by seining or hook-
and-line capture.
In the Susitna River drainage above the Yentna River confluence, a weir was operated on the
Deshka River from June 9 to September 3, 2013, and on Montana Creek from June 17 to
September 2, 2013. Sonar was operated on the Middle Fork Chulitna River from June 20 to
August 5, 2013. In the Yentna River drainage, sonar was operated on the Talachulitna River
from June 11 to July 31, 2013.
Finally, fish tagged in the Lower River that were collected at the Curry fishwheels were
examined for mark rates. The size characteristics of the tagged and untagged fish at Curry were
used along with weir-based information to estimate escapement and for testing assumptions of
the mark-recapture experiment each year.
A two-event, capture-recapture experiment was also used to estimate the abundance of coho
salmon in the Susitna River upstream of the confluence with the Yentna River. Only t wo
fishwheels were used on the Lower River (PRM 33–34) to capture coho salmon for marking with
radio tags, from July 6 to August 31, 2013 (Table A-1; Figures A-1, A-2, and A-6). Coho
salmon were counted and inspected for tags at the weirs on the Deshka River and Montana
Creek, as described above. In addition, the Middle Fork Chulitna River was evaluated as a
possible site using the 2012 coho salmon telemetry analyses; but, the relative size of the 2012
coho salmon return indicated too few tags were likely to be recovered to justify using the Middle
Fork Chulitna River as a recapture site in 2013.
4.8.1. Variances
Montana Creek was selected as a weir site instead of Willow Creek in 2013. 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
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similar Chinook and coho salmon run sizes. This variance did not affect achieving study
Objective 8.
A weir was not operated on the Middle Fork Chulitna River in 2013. In June, 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
abundance experiment. River discharges remained too high to install the weir at a later date.
This variance may provide sufficient data to meet the abundance and distribution objectives for
the Susitna River above the Yentna River, and may not affect achieving the Susitna abundance
estimate component of study Objective 8.
No weir or sonar operations occurred at Lake Creek in 2013. In June, the stream discharge
remained too high for weir installation and was hazardous for boat operation. Also, direct access
to a site suitable for either a weir or sonar operation was not possible. This variance will affect
achieving the Yentna component of study Objective 8 as an abundance estimate will not be
determined.
A weir was not operated on the Talachulitna River in 2013. In June, the stream discharge was
too high for weir installation; instead, a sonar unit was employed in order to obtain the counts
necessary for the abundance experiment. Discharges remained too high to install the weir at a
later date. No sampling at Lake Creek leaves only the Talachulitna River as a sampling site on
the Yentna River. One site is not adequate for testing of the assumptions of the capture-
recapture abundance experiment for Chinook salmon in the Yentna River. This variance will
affect achieving the Yentna component of study Objective 8 as an abundance estimate will not
be determined.
Although not part of the Study Plan, a picket weir was operated on the Indian River through its
entire Chinook salmon run (Section 4.1.5.2) and size-specific mark rates pertaining to Lower
River tagged fish were obtained. This variance will improve the likelihood of achieving the
Middle River component of study Objective 8 (see Section 4.1.8.3 for details).
5. RESULTS
Data developed in support of the ISR is available for download at
http://gis.suhydro.org/reports/isr/9/9.7 and include the files ISR_9_7_ESCAPE_LGL 2013
Fishwheel Catch Tag Dataset QC3-sub20131216.xlsx, ISR_9_7_ESCAPE_LGL 2013 Curry
Sonar ARIS Dataset QC3-sub20131218.xlsx, ISR_9_7_ESCAPE_LGL 2013 Indian River Weir
Passage Dataset QC3-sub20131218.xlsx, and ISR_9_7_ESCAPE_SuWa LGL ESCAPE
TelemMgr Export Flat Tables QC3 DR 20131213.
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.
Detailed summaries of fish capture and tagging are provided in Appendix A.
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5.1.1. Fish Capture
5.1.1.1. Lower River
A total of 2,063 Chinook (1,232 large, 831 small), 3,512 chum, 3,277 coho, 33,995 pink, and 624
sockeye salmon were captured in the mainstem of the Lower River (Table A-5). The peak of
Chinook salmon catch was on June 12 (204), whereas peak catches for pink and coho salmon
were over a month later on July 20 (4,551) and August 3 (186), respectively. Catch-per-unit-
effort for pink salmon peaked at 201 fish per hour (west bank), whereas CPUE for Chinook and
coho salmon peaked at 10.6 (west bank) and 9.1 (west bank) fish per hour, respectively (Figure
A-10). Chinook salmon catches were substantially higher in the west bank fishwheel during the
peak of the run, coho salmon catches were consistently slightly higher in the west bank
fishwheel, whereas pink salmon catches were relatively balanced along each bank.
5.1.1.2. Yentna River
Of the 2,295 adult Chinook salmon (1,201 large, 1,094 small) captured in the lower Yentna
River, the majority (87 percent) were captured in fishwheels, and the remaining 13 percent in
gillnets (
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Table A-6). Daily catch peaked at 259 fish on June 17. The magnitude and timing of the peak
CPUE for Chinook salmon was very similar for the north and south bank fishwheels (Figure A-
11). Chinook salmon captured in the Lower River and Yentna River were similarly sized (Table
A-7).
5.1.1.3. Middle River
In the Middle River, 616 large Chinook, 336 small Chinook, 3,417 chum, 1,734 coho, 15,695
pink, and 276 sockeye salmon were captured, including recaptures (Table A-8). The majority of
Chinook and coho salmon were captured at Site 1, whereas the most sockeye salmon were
captured at Site 2, and the most chum and pink salmon were captured at Site 3. Peak catches
were earliest for Chinook salmon (July 1; 52 fish), followed by sockeye (August 1; 9 fish), chum
and pink (August 3; 259 and 1,422 fish, respectively), and coho salmon (August 17; 139 fish).
CPUE was highest for pink salmon (90.1 fish/hour; Site 3), followed by chum (11.3 fish/hour;
Site 3), coho (9.7 fish/hour; Site 1), large Chinook (2.2 fish/hour; Site 1), and sockeye salmon
(0.7 fish/hour; Site 3; Figure A-12). The mean length of large Chinook salmon captured in the
Middle River (69.6 cm [27.4 in]; Table A-4) was greater than the mean length of large Chinook
salmon captured in the Lower River and Yentna River (Table A-7). From largest to smallest,
mean lengths for chum, coho, sockeye, and pink salmon captured in the Middle River were 59.0
cm, 51.1 cm, 44.8 cm, and 41.6 cm [23.2 in, 20.1 in, 17.6 in, and 16.4 in], respectively (Table A-
4). Six other fish species were captured and released at the Middle River fishwheels, including
104 round whitefish Prosopium cylindraceum, 59 rainbow trout O. mykiss, 54 Arctic grayling
Thymallus arcticus, 20 humpback whitefish Coregonus pidschian, 20 longnose sucker
Catostomus catostomus, 14 Dolly Varden Salvelinus malma, and 2 burbot Lota lota (Table A-4).
5.1.2. Radio-tagging
5.1.2.1. Lower River
In the Lower River fishwheels, 580 large Chinook, 596 coho, and 197 pink salmon were radio-
tagged (Table A-1; Figure A-6). These tagged fish represent 31 percent of the Chinook, 18
percent of the coho, and 0.6 percent of the pink salmon in the total fishwheel catch. Between the
two fishwheels in the Lower River, 66 percent of the radio tags were deployed in the west bank
fishwheel. In the Lower River gillnetting, 118 large Chinook were radio-tagged, which was 71
percent of the gillnet catch. Daily radio-tag deployment in the Lower River peaked at 128 for
Chinook salmon on June 9, 36 for coho salmon on July 16, and 17 for pink salmon on July 24
and 25, 2013.
5.1.2.2. Yentna River
In the Yentna River fishwheels, 425 large Chinook salmon were radio-tagged (Table A-2; Figure
A-7), which was 21 percent of the total fishwheel catch. In the gillnetting, 267 Chinook salmon
were marked with radio tags, which was 86 percent of the gillnet catch. Between the two
fishwheels in the Yentna River, 66 percent of the radio tags were deployed in the south bank
fishwheel. Radio-tag deployment for Chinook salmon at the Yentna River peaked at 79 tags on
June 14, 2013.
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5.1.2.3. Middle River
In the Middle River, radio tags were applied to 536 large Chinook, 67 small Chinook, 201 chum,
242 coho, 200 pink, and 139 sockeye salmon (Table A-3; Figure A-8). Of the untagged, healthy
adult salmon captured at the Middle River fishwheels, radio tags were applied to 89.9 percent of
large Chinook, 20.2 percent of small Chinook, 6.0 percent of chum, 13.7 percent of coho, 1.3
percent of pink, and 80.3 percent of sockeye salmon. The daily number of radio tags applied
peaked at 50 for large Chinook, 7 for small Chinook, 20 for chum, 26 for coho, 25 for pink, and
8 for sockeye salmon (Figure A-8). Radio tags were deployed in proportion to catch for Chinook
and sockeye salmon in 2013 (Figure A-13). In contrast, relative to fishwheel catches in the
1980s, 2012, and 2013, the early components of the 2013 chum, coho, and pink salmon runs
were likely over-tagged, and the later components of these runs were under-tagged.
5.1.3. Spaghetti-tagging
In the Middle River, spaghetti tags were applied as the primary mark to 1,959 chum, 962 coho,
and 9,105 pink salmon (Table A-3; Figure A-14). The daily number of spaghetti tags deployed
peaked at 139 for chum, 105 for coho, and 919 for pink salmon. Incidentally, seven Chinook (5
large, 2 small) and six sockeye salmon were also spaghetti-tagged.
A number of previously radio- and spaghetti-tagged salmon were recaptured at the Middle River
fishwheels, including 20 large Chinook, 4 small Chinook, 82 chum, 37 coho, 460 pink, and 3
sockeye salmon. Of these, four Chinook and two coho salmon were radio-tagged fish released at
the Lower River fishwheels.
5.1.4. Numbers and Size of Marked and Unmarked Fish at Selected Locations
5.1.4.1. Deshka River Weir
An estimated 18,003 Chinook salmon measuring 50 cm MEF or greater passed the Deshka River
weir during June 9 to September 2, 2013, out of a total count of 18,531 Chinook salmon of all
sizes. One hundred forty eight, or 0.82 percent, were radio-tagged fish (Table B-1) which were
assumed to have spawned above the weir. The cumulative length-frequency distribution for
Chinook salmon sampled at the Deshka River weir was significantly different than that for radio-
tagged fish passing the weir (D = 0.243, p < 0.001), providing strong evidence of size biased
sampling during the marking event. The cumulative length-frequency distribution for Chinook
salmon sampled at the Deshka River weir was also significantly different than that for all radio-
tagged fish above the tagging site (D = 0.245, p < 0.001) with the mean length of radio-tagged
Chinook salmon (68.6cm) being smaller than that of Chinook salmon measuring 50 cm or
greater that passed the Deshka River weir (73.4 cm; Table B-2).
A total of 22,141 coho salmon were counted during July 10 to September 3, 2013, all of which
were estimated to be 40 cm MEF or greater. Sixty seven, or 0.30 percent, were radio-tagged
fish (Table B-1) which passed the weir when counting was being conducted and later assumed to
have spawned above the weir. The cumulative length-frequency distribution for coho salmon
sampled at the Deshka River weir was significantly different than that for radio-tagged fish
passing the weir (D = 0.439, p < 0.001), providing strong evidence of size biased sampling
during the marking event. The cumulative length-frequency distribution for coho salmon
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sampled at the Deshka River weir was also significantly different than that for all radio-tagged
fish above the tagging site (D = 0.410, p < 0.001) with the mean length of radio-tagged coho
salmon (50.3 cm) smaller than coho salmon that passed the Deshka River weir (55.4 cm; Table
B-2).
5.1.4.2. Montana Creek Weir
An estimated 1,949 Chinook salmon measuring 50 cm or greater passed the Montana Creek weir
during July 8 to August 20 and August 26–27, 2013, out of a total count of 2,015 Chinook
salmon of all sizes. Eleven, or 0.56 percent, were radio-tagged fish (Table B-3) which were
assumed to have spawned above the weir. The cumulative length-frequency distribution for
Chinook salmon sampled at the Montana Creek weir was not significantly different than that for
radio-tagged fish passing the weir (D = 0.233, p = 0.663). 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 = 0.136, p = 0.006), with the mean
length of radio-tagged Chinook salmon (68.6 cm) slightly larger than Chinook salmon measuring
50 cm or greater that passed the Deshka River weir (67.2 cm; Table B-2).
A total of 765 coho salmon were counted during July 31 to August 20 and August 26 to
September 3, 2013, all of which were estimated to be 40 cm or greater. Seven, or 0.92 percent,
were radio-tagged fish (Table B-3) which passed the weir when counting was being conducted
and later assumed to have spawned above the weir. The cumulative length-frequency
distribution for coho salmon sampled at the Montana Creek weir was significantly different than
that for radio-tagged fish passing the weir (D = 0.657, p = 0.005), providing strong evidence of
size biased sampling during the marking event. The cumulative length-frequency distribution for
coho salmon sampled at the Montana Creek weir was also significantly different than that for all
radio-tagged fish above the tagging site (D = 0.263, p < 0.001) with the mean length of radio-
tagged coho salmon (50.3 cm) smaller than coho salmon that passed the Deshka River weir (53.2
cm; Table B-2).
5.1.4.3. Middle Fork Chulitna River Sonar
This data is currently under analysis.
5.1.4.4. Talachulitna River Sonar
This data is currently under analysis.
5.1.4.5. Indian River Weir
Net passage of Chinook salmon inspected for tags was 1,405 fish, including 1,137 large fish, 294
small fish, and minus 26 fish with an unknown length category (Table 5.1-2; Table B-4; Figure
B-2). An additional net passage of 34 Chinook salmon were not inspected for tags, including 31
large fish and 3 fish with an unknown length category. Chinook salmon were counted at the weir
from June 27 to August 19, and net passage peaked at 192 fish on July 10. Of the Chinook
salmon inspected for tags, with a known length category, 72 (6.3 percent) were large fish and 13
(4.4 percent) were small fish with radio tags applied in the Middle River.
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Net passage of chum salmon inspected for tags was 12,906 fish, including 12,847 fish measuring
40 cm (15.7 in) or greater in length, one fish measuring less than 40 cm (15.7 in) in length, and
58 fish with an unknown length category (Table B-4; Figure B-2). An additional net passage of
6 fish were not inspected for tags, including four fish measuring 40 cm (15.7 in) or greater in
length and two fish with an unknown length category. Chum salmon were counted at the weir
from June 27 to August 20, and net passage peaked at 884 fish on July 30. Of the 12,847 chum
salmon measuring 40 cm (15.7 in) or greater in length that were inspected, 542 (4.2 percent)
were tagged, which included 51 (0.4 percent) radio tags, and 491 (3.8 percent) spaghetti tags.
Net passage of coho salmon inspected for tags was 525 fish, including 514 fish measuring 40 cm
(15.7 in) or greater in length, 12 fish measuring less than 40 cm (15.7 in) in length, and minus
one fish with an unknown length category (Table B-4; Figure B-2). An additional net passage of
20 fish measuring 40 cm (15.7 in) or greater in length were not inspected for tags. Coho salmon
were counted at the weir from July 20 to August 20, and net passage peaked at 300 fish on
August 19. Of the 514 coho salmon measuring 40 cm (15.7 in) or greater in length that were
inspected, 53 (10.3 percent) were tagged, which included 17 (3.3 percent) radio tags and 36 (7.0
percent) spaghetti tags.
Net passage of pink salmon inspected for tags was 37,181 fish (Table B-4; Figure B-2). An
additional net passage of 66 fish were not fully inspected for tags. Pink salmon were counted at
the weir from July 20 to August 20, and net passage peaked at 4,292 fish on August 10. Of the
pink salmon inspected, 2,010 (5.4 percent) were tagged, including 35 (0.1 percent) radio tags and
1,975 (5.3 percent) spaghetti tags.
Net passage of sockeye salmon inspected for tags was 127 fish, including 120 fish measuring 40
cm (15.7 in) or greater in length, six fish measuring less than 40 cm (15.7 in) in length, and one
fish with an unknown length category (Table B-4; Figure B-2). Sockeye salmon were counted at
the weir from July 20 to August 18, and net passage peaked at 16 fish on August 17. Of the
sockeye salmon measuring 40 cm (15.7 in) or greater in length that were inspected for tags, three
(2.5 percent) were radio-tagged.
Other fish species counted at the weir included: rainbow trout (587 up, 274 down), Arctic
grayling (93 up, 19 down), round whitefish (71 up, 24 down), humpback whitefish (22 up, 1
down), longnose sucker (8 up, 0 down), and Dolly Varden (12 up, 10 down; Figure B-3). A
small number of juvenile salmon and sculpin species were also observed passing through the
chute.
The mean length of tagged Chinook salmon (68.0 cm [26.7 in]) measured from video imagery at
the Indian River weir was slightly smaller than the mean length of untagged fish (69.8 cm [27.5
in]; Table B-2). However, cumulative length-frequency distributions for marked, inspected, and
recaptured Chinook salmon were statistically similar, which indicates no evidence of size-
selective radio-tagging for large Chinook salmon at the Middle River fishwheels or at the weir
(Figure A-15). These results suggest radio tags were randomly applied to fish in the Middle
River regardless of size.
Cumulative length-frequency distributions for fish radio-tagged in the Middle River and those
inspected at the weir were similar for small Chinook (Dmax = 0.10, P = 0.69), coho (Dmax = 0.11,
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P = 0.11), pink (Dmax = 0.09, P = 0.14), and sockeye salmon (Dmax = 0.17, P = 0.09; Figure A-
15). In contrast, the cumulative length-frequency distributions of chum salmon radio-tagged in
the Middle River and those inspected at the weir were significantly different (Dmax = 0.13, P =
0.01); although the mean lengths of tagged (59.7 cm [23.5 in]) and inspected (60.4 cm [23.8 in])
fish differed only slightly. Nonetheless, for small Chinook, chum, coho, pink, and sockeye
salmon, too few radio-tagged fish (n ≤ 4) were recaptured at the weir to make additional
comparisons and test for size selectivity.
There was evidence to suggest size-selective spaghetti-tagging occurred at the Middle River
fishwheels for chum salmon, but not for pink salmon (Figure A-16). The mean length of chum
salmon spaghetti-tagged at the Middle River fishwheels (59.0 cm [23.2 in]) was slightly smaller
than the mean length of fish inspected at the weir (60.4 cm [23.8 in]). Spaghetti-tagged coho
salmon released in the Middle River, and those fish inspected at the weir, had similar length
distributions (Dmax = 0.06, P = 0.66); however, too few spaghetti-tagged coho salmon (n = 14)
were recaptured at the weir for further statistical comparisons.
5.1.5. Examining Handling-Induced Changes in Behavior
Of the 536 large Chinook salmon that were radio-tagged and released at the Middle River
fishwheels, 14 (2.6 percent) were recaptured (i.e., captured twice) at one of the Middle River
fishwheels. The elapsed time between tag and recapture events ranged from a few minutes to
over eight days (median = 0.8 days). All recaptured fish were released and subsequently
assigned spawning fates (i.e., classified into a specific tributary or mainstem spawning location).
Four (6.0 percent) of the 67 radio-tagged small Chinook salmon were recaptured, of which three
were assigned spawning fates (median time between capture events was 1.5 days). The elapsed
time between capture events for chum (n = 3), pink (n = 10), and sockeye (n = 3) salmon was
0.3, 0.3, and 0.2 days, respectively; and all of these recaptures were assigned spawning fates.
The relatively short time period between capture events and large proportion of recaptured fish
that were assigned spawning fates suggests the additional handling time did not substantially
influence behavior.
5.1.6. Assessing Any Stock- and Size-selective Capture
5.1.6.1. Use of ARIS to Assess Fishwheel Effectiveness and Fish Approach Behavior
Catch-per-unit-effort data at the ARIS (Unit 1), or the number of targets counted per hour of
imagery reviewed, showed several pulses of fish passing Site 1 in the Middle River (Figure A-
17). These included: two small pulses on June 10–11 (peak = 1.7 fish/hour) and June 16–17
(peak = 3.0 fish/hour), a moderate but steady pulse from late June to early July (peak = 6.0
fish/hour), a large pulse from August 30 to September 3 (peak = 17.0 fish/hour), and a small but
steady pulse for the remainder of September. The number of adult salmon captured at the Site 1
fishwheel was compared to concurrent net upstream counts of fish on the ARIS (Unit 1; Figure
A-18). The two pulses of fish observed in June on Unit 1 corresponded to peak catches of Arctic
grayling, rainbow trout, and round whitefish at the Site 1 fishwheel. Although these pulses of
smaller-sized fish measured 50 cm (19.7 in) or greater on the ARIS imagery, the vast majority of
these species measured less than 50 cm (19.7 in) when sampled at the fishwheel (and thus are not
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reflected in the fishwheel catch data in Figure A-18). These results suggest that the length
measurements collected from ARIS imagery in the first half of June may be biased high.
The ARIS data provided a good indication that the leading edge of the Chinook salmon run was
captured at the Middle River fishwheels. As counts at Unit 1 increased from late June through
early July, there was a concurrent pulse in Chinook salmon catches at the Site 1 fishwheel (peak
of 51 Chinook salmon on July 1). From August 30 to September 3, fishwheel catches at Site 1
were comprised largely of coho salmon.
The ARIS data suggests that the trailing end of the coho salmon run was not well-represented by
fishwheel catches. Despite the small but steady stream of fish observed using ARIS after
September 4, which presumably was comprised largely of coho salmon, only five adult salmon
(three coho, one chum, and one sockeye salmon) were captured at the Site 1 fishwheel from
September 4 to 17. The decrease in turbidity in the first half of September (Figure A-17) likely
contributed to the apparent low fishwheel catches, as fish would be able to see the fishwheel
baskets and avoid being captured.
From June 16 to July 12, when most fish measuring 50 cm (19.7 in) or greater passing Site 1
were Chinook salmon, the just over half (58.4 percent) of the targets at Unit 1 were within 6 m
(19.7 ft) of the transducer (Figure A-19). From September 1–30, when most fish measuring 40
cm (15.7 in) or greater passing Site 1 were likely coho salmon, a larger proportion (69.4 percent)
of targets at Unit 1 were within 6 m (19.7 ft) of the transducer. Counts at that range for Unit 2 in
September indicated that relatively few fish migrated greater than 13 m (42.7 ft) from the
transducer.
Counts of upstream-moving targets on days when the full 24 hours of imagery were reviewed
showed that the majority of fish (presumably Chinook salmon) passed between midnight and
11:00 A.M. from June 16 to July 12 (Figure A-20). In contrast, from September 1 to 30, fish
passage (presumably mostly coho salmon) was highest from 8:00 A.M. to 8:00 P.M.
5.1.6.2. 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 fate showed no evidence to suggest that radio-tagged large Chinook, chum,
or pink salmon were bank-oriented when passing through the Middle River. However, due to
small sample sizes, at least one cell in each of the species-specific tests had an expected value of
less than five. In contrast, sockeye salmon appeared bank-oriented in the Middle River (χ2 =
13.9, df = 1, P < 0.001). Eighty percent (16 of 20) of sockeye salmon radio-tagged on the left
bank (when looking downstream) were assigned to left-bank spawning areas, and 76 percent (19
of 25) of fish tagged on the right bank returned to right-bank spawning areas. All small Chinook
salmon returned to right-bank spawning areas, regardless of whether they were captured on the
left (n = 8) or right (n = 23) bank.
Mainstem spawning populations did not appear more vulnerable to recapture than those fish
bound for tributaries. Of the 31 radio-tagged salmon released and recaptured at the Middle River
fishwheels that were subsequently assigned spawning fates, 27 (87 percent) were assigned to
tributaries and only four (13 percent) were assigned to mainstem areas. Similar proportions were
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observed for radio-tagged fish that were never recaptured (88 percent to tributaries and 12
percent to mainstem areas).
5.1.6.3. Size-related Comparisons
5.1.6.3.1. 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 = 0.308, p
< 0.001) and the east bank fishwheel (D = 0.615, p < 0.001). Chinook salmon caught in the west
bank fishwheel were larger than those from the east bank fishwheel (D = 0.311, p < 0.001).
Average lengths (MEF) of Chinook salmon for each capture station was 67.8 cm for mid-river
gillnets, 57.4 cm for the west bank fishwheel, and 46.4 cm for the east bank fishwheel. Coho
salmon caught in the west bank fishwheel were significantly larger than those caught in the east
bank fishwheel (D = 0.073, p = 0.001). Average lengths were 50.0 cm for west bank fish and
49.2 cm for east bank fish. There was no difference detected between lengths of pink salmon
caught at the two fishwheels (D = 0.070, p = 0.968), with average lengths of 43.0 cm for west
bank fish and 42.8 cm for east bank fish (Figure A-21).
For Chinook salmon measuring 50 cm 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 = 0.153, p < 0.001). This difference is due largely to the tagging strategy
used at the site, which called for Chinook salmon less than 58 cm to be tagged at approximated
1/3 the rate of larger fish. No significant difference was detected between the length
distributions of Chinook salmon measuring 58 cm or greater caught at the Lower River site and
those tagged (D = 0.058, p = 0.231). For coho salmon measuring 40 cm or greater, no 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 = 0.038, p = 0.481). For pink salmon,
length data were collected only for fish that were radio-tagged (Figure A-22).
For Chinook salmon measuring 50 cm or greater, a significant difference was detected between
length distributions of radio-tagged fish that spawned above the Lower River tagging site and
fish recaptured at the Montana Creek and Deshka River weirs (D = 0.272, p < 0.001). There was
a significant difference detected between the length distribution of Chinook salmon measuring
50 cm or greater passing the Deshka River weir and recaptured radio-tagged fish that spawned
above the weir (D = 0.243, p < 0.001). No significant difference was detected at the Montana
Creek weir between the length distributions of Chinook salmon measuring 50 cm or greater
spawning above the weir and recaptures at the weir (D = 0.233, p = 0.663). For coho salmon
measuring 40 cm or greater, no significant difference was detected between length distributions
of radio-tagged fish that spawned above the lower river tagging site and fish recaptured at the
Montana Creek and Deshka River weirs (D = 0.079, p = 0.754). There was a significant
difference detected between the length distribution of coho salmon measuring 40 cm or greater
passing the Deshka River weir and recaptured radio-tagged fish that spawned above the weir (D
= 0.439, p < 0.001). Similarly, a significant difference was detected at the Montana Creek weir
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between the length distributions of coho salmon measuring 40 cm or greater spawning above the
weir and recaptures at the weir (D = 0.657, p = 0.005; Figure A-23).
5.1.6.3.2. Yentna River
Comparisons of cumulative length-frequency distributions for all Chinook salmon captured at
the Yentna River tagging site showed significant differences between the size distributions of
fish caught at the north bank fishwheel, the south bank fishwheel, and mid-river gillnetting sites.
Chinook salmon caught in mid-river gillnets were larger than fish caught in the north bank
fishwheel (D = 0.736, p < 0.001) and the south bank fishwheel (D = 0.579, p < 0.001). Chinook
salmon caught in the south bank fishwheel were larger than those from the north bank fishwheel
(D = 0.233, p < 0.001). Average lengths (MEF) of Chinook salmon for each capture station was
75.9 cm for mid-river gillnets, 50.3 cm for the south bank fishwheel, and 43.0 cm for the east
bank fishwheel (Figure A-24).
For Chinook salmon measuring 50 cm or greater, a significant difference was detected between
the length distributions of fish captured at the Yentna River tagging site and only those fish
radio-tagged at that site (D = 0.174, p < 0.001). This difference is due largely to the tagging
strategy used at the site, which called for Chinook salmon measuring less than 58 cm to be
tagged at approximated 1/3 the rate of larger fish. No significant difference was detected
between the length distributions of Chinook salmon measuring 58 cm or greater caught at the
Yentna River site and those tagged (D = 0.022, p = 0.995; Figure A-25).
5.1.6.3.3. Middle River
Comparisons of cumulative length-frequency distributions for fish captured at the Middle River
fishwheels showed significant differences for Chinook salmon captured at sites 1 and 2; chum
salmon captured at sites 1 and 2, and sites 2 and 3; coho salmon captured at sites 1 and 2, and
sites 1 and 3; and sockeye salmon captured at sites 1 and 2, and sites 1 and 3 (Figure A-26).
Pink salmon were the only species with similar length-frequency distributions across all three
sites. The mean lengths of fish captured at Site 1 were greater than those captured at Site 2 for
Chinook (58.4 vs. 54.6 cm [23.0 vs. 21.5 in]), chum (59.1 vs. 58.4 cm [23.2 vs. 23.0 in]), coho
(51.9 vs. 50.0 cm [23.3 vs. 19.7 in]). The mean length of chum salmon captured at Site 3 (59.2
cm [23.3 in]) was greater than at Site 2 (58.4 cm [23.0 in]). Results associated with Site 3 are
limited to species other than Chinook salmon and are confounded with time. Fishing at Site 3
was limited to the latter part of the run (i.e., July 17 and later), and sample sizes were too small
to compare period-specific data.
It is worth noting that a larger proportion of Chinook, coho, and sockeye salmon captured in
2013 were comprised of smaller-sized fish (commonly referred to as jacks) compared to 2012.
In 2013, 35 percent (336 of 952) of Chinook salmon measured less than 50 cm (19.7 in) in length
(versus 25 percent in 2012), and 36 percent (100 of 276) of sockeye salmon measured less than
40 cm (15.7 in) in length (versus 8 percent in 2012). When it became apparent in late June that
there were a large number of small Chinook salmon being captured and the tagging goal for large
Chinook (and sockeye) salmon would not likely be met, the decision was made to allocate some
radio tags (n = 67) to small Chinook salmon.
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Significant differences in the length distributions of radio-tagged and captured fish were found
for small Chinook, chum, and pink salmon, but not for large Chinook, coho, or sockeye salmon
(Figure A-27). In the three cases where significant differences were found, the mean lengths for
radio-tagged fish were greater than mean lengths for those captured (38.1 vs. 36.3 cm [15.0 vs.
14.3 in] for small Chinook; 59.7 vs. 59.0 cm [23.5 vs. 23.2 in] for chum; and 42.9 vs. 41.6 cm
[16.9 vs. 16.4 in] for pink salmon). For chum, coho, and pink salmon, the cumulative length-
frequency distributions of spaghetti-tagged fish were similar to all other fish captured (Figure A-
27). For small Chinook salmon, results were consistent with tagging effort as it was not random
across all sizes, but instead was limited to the larger segment of the small fish captured in the
fishwheels.
5.2. Objective 2: Determine the migration behavior and spawning
locations of radio-tagged fish in the Lower, Middle, and Upper
Susitna River
5.2.1. Tag Returns
Forty-six of the radio tags deployed in the Lower River and Yentna River were recovered by
project field staff (Table E-1). This included 25 large Chinook salmon, recovered in the Deshka
(5), Indian (3), and Talachulitna (1) rivers, as well as Johnson (1), Lake (6), Moose (1), Peter’s
(3), Prairie (1), Willow (3), and 8 Mile (1) creeks. Twenty-one coho salmon tagged in the Lower
River were recovered from a variety of locations, including the Deshka (2), Lower Susitna (2),
Talachulitna (2), and Yentna (3) rivers; and Caswell (3), Chase (1), Clear (3), Johnson (1), Lake
(1), Peter’s (1), Sheep (1), and Sunshine (1) creeks.
Additionally, 54 of the radio tags initially deployed in the Middle Susitna River were recovered
by an glers (8) and project field staff (46; Table E-2). Twenty-four large Chinook salmon were
recovered from the Chulitna (1), Indian (17), and Middle Susitna (1) rivers, as well as Portage
(2) and Troublesome (1) creeks. Recovery location information was not provided for two of the
Chinook salmon tags recovered from this size cohort. Six small Chinook salmon were recovered
from the Indian (4) and Middle Susitna (1) rivers, as well as one from Spink Creek, a tributary of
the Chulitna River. Eleven pink salmon were recovered from the Indian (4) and Middle Susitna
(6) rivers, along with one from Fifth of July Creek. One sockeye salmon was recovered from
Slough 8A of the Middle River. Seven chum salmon were recovered from the Indian (4) and
Middle Susitna (1) rivers, as well as Clear (1) and Montana (1) creeks. Lastly, five coho salmon
were recovered from Indian River (1), as well as Clear (1), Lake (1), Sunshine (1), and Whiskers
(1) creeks.
5.2.2. Stock Classifications and Spawning Locations – Lower River
5.2.2.1. Chinook Salmon
Of the 689 Chinook salmon tagged in the Lower River, 621 (90 percent) were classified by
destination. Of these, 617 (99 percent) went to tributaries (mainly the Deshka, Talkeetna,
Chulitna, or Yentna rivers), and 4 (1 percent) went to destinations in the mainstem Susitna River
(Table 5.2-1; Figure 5.2-1; Figure D-1 and D-2). The remaining 68 Chinook salmon, not able to
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be classified by a specific destination (see “Other Fates” classification in Table 5.2-1), exhibited
movements that prevented conclusive assignment to the mainstem or tributaries.
5.2.2.2. Coho Salmon
Of the 596 coho salmon tagged in the Lower River, 500 (84 percent) were classified by
destination. Of these, 478 (96 percent) went to tributaries (mainly the Yentna, Deshka,
Talkeetna, or Chulitna rivers), and 22 (4 percent) went to destinations in the mainstem Susitna
River (Table 5.2-1; Figure 5.2-1; Figures D-1, D-3, and D-4). The remaining 96 coho salmon,
not able to be classified by a specific destination (see “Other Fates” classification in Table
5.2-1), exhibited movements that prevented conclusive assignment to the mainstem or tributaries.
Coho salmon were tracked to twelve potential spawning sites within mainstem habitats of the
Lower River (Figure D-3). Sites included six main channel, five slough/side channels, and one
tributary delta. During the survey period, mainstem water clarity was ideal for visual
confirmation of spawning activity; however, none of the twelve potential spawning sites were
confirmed for spawning.
5.2.2.3. Pink Salmon
Of the 200 pink salmon tagged in the Lower River, 116 (58 percent) were classified by
destination. Of these, 98 (84 percent) went to tributaries (mainly the Deshka or Yentna rivers, or
Montana or Willow creeks) and 18 (16 percent) went to destinations in the mainstem Susitna
River (Table 5.2-1; Figure 5.2-1; Figures D-1, D-5, and D-6). The remaining salmon
(42 percent) were not classified to a specific destination due to insufficient telemetry data for the
specific timing and distribution of pink salmon in the Lower River. This issue will be resolved
in year 2 studies by enhancing fixed-station and/or mobile-survey coverage for pink salmon in
the Lower River (Table 5.2-1).
5.2.3. Stock Classifications and Spawning Locations – Yentna River
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). Of the 692 Chinook salmon released in the
Yentna River, 596 (86 percent) were classified with a Yentna destination, and 6 (1 percent) were
classified in other Susitna River tributaries (Talkeetna River, Montana Creek, and Chulitna
River; Table 5.2-1). The remaining 90 salmon were not able to be classified by a specific
destination.
5.2.4. Stock Classifications and Spawning Locations – Middle and Upper River
5.2.4.1. Chinook Salmon
Of the 536 large Chinook salmon radio-tagged in the Middle River, 449 (84 percent) were
classified by spawning destination (Table 5.2-1). Of these, 422 (94 percent) went to tributaries
(mainly Portage Creek or Indian River; Figure D-7) and 27 (6 percent) went to destinations in the
mainstem Susitna River (Table 5.2-1; Figures D-2 and D-8). Destinations of the remaining 87
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large Chinook salmon could not be classified, due to movements that prevented conclusive
assignment to the mainstem or tributaries (Table 5.2-1).
In addition to the large Chinook described above, 67 small Chinook salmon were radio-tagged
and released in the Middle River. In all, 45 (67 percent) were classified by destination (Table
5.2-1). Of these, 42 (93 percent) went to tributaries (mainly Indian River or Portage Creek;
Figure D-7) and 3 (7 percent) went to destinations in the mainstem Susitna River (Table 5.2-1;
Figure 5.2-1). Destinations of the remaining 22 small Chinook salmon could not be classified
(Table 5.2-1).
Chinook salmon were tracked to 13 potential mainstem spawning sites in the Middle River
between Lane and Chinook creeks (Table D-2; Figure D-8). To confirm spawning activity, each
of these sites was visually examined during mobile surveys (e.g., by helicopter or boat, or on foot
during HSC surveys). An ARIS unit was used at sites where water conditions were too turbid for
visual examination. The only potential evidence of spawning was observed with ARIS at Site 9
(Indian River Delta; Table D-1), where a holding Chinook salmon exhibited behavior indicative
of nest guarding; redds or redd digging behavior could not be confirmed. Six turbid water sites
(five mainstem and one side channel) were not surveyed due to inaccessibility by the boat for
ARIS sampling, and one mainstem site was not surveyed because the physical characteristics
(e.g., water velocity and turbulence) of the river were considered unsuitable for spawning. One
site (Site 13) was above Devils Canyon Impediment 1 and inaccessible by boat, and the river was
too turbid for visual confirmation of spawning activity during aerial surveys. Holding behavior
was observed, but only at tributary delta habitats. Groups of radio-tagged Chinook salmon (i.e.,
more than one) were detected at four sites (Indian River Delta, Portage Creek, Side Channel 21,
and Site 11), but only the Indian River Delta was confirmed as a spawning site. The only repeat
confirmed spawning sites in 2012 and 2013 were at tributary deltas.
5.2.4.2. Chum Salmon
Of the 201 chum salmon tagged in the Middle River, 164 (82 percent) were classified by
destination (Table 5.2-1). Of these, 147 (90 percent) went to tributaries (mainly Portage Creek,
or Indian or Talkeetna rivers; Figure D-7) and 17 (10 percent) went to destinations in the
mainstem Susitna River (Table 5.2-1; Figure 5.2-1; Figures D-9 and D-10). The remaining 37
chum salmon, not able to be classified by a specific destination, exhibited movements that
prevented conclusive assignment to the mainstem or tributaries (Table 5.2-1).
Chum salmon were tracked to nine potential mainstem spawning locations in the Middle River
(Table D-3; Figure D-10). Each site was examined during mobile surveys (e.g., helicopter, boat,
or HSC). An ARIS was used at sites where water conditions were too turbid for visual
confirmation. Spawning by chum salmon was visually confirmed at five sites (four sloughs and
one side channel). Two mainstem sites were not surveyed as the physical characteristics (e.g.,
water velocity and turbulence) of the river were considered unsuitable as spawning habitat, and
one side channel site was not surveyed due to access difficulty with the boat for ARIS sampling.
The only site where fish were observed holding, but spawning could not be confirmed, was at the
delta of Jack Long Creek. Two sites (sloughs 8A and 9) had more than one tagged chum salmon
detected. All 2013 confirmed spawning sites were also surveyed and confirmed in 2012.
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5.2.4.3. Coho Salmon
Of the 242 coho salmon tagged in the Middle River, 173 (71 percent) were classified by
destination (Table 5.2-1). Of these, 154 (89 percent) went to tributaries (mainly Talkeetna,
Chulitna, or Indian rivers) and 19 (11 percent) went to destinations in the mainstem Susitna
River (Table 5.2-1; Figure 5.2-1; Figures D-3 and D-4). The remaining 69 coho salmon, not able
to be classified by a specific destination, exhibited movements that prevented conclusive
assignment to the mainstem or tributaries (Table 5.2-1).
Coho salmon were tracked to 17 potential spawning sites within mainstem habitats of the Middle
River (Figure D-4). Sites included seven main channel, seven side channel/sough, and three
tributary deltas. During the survey period, mainstem water clarity was ideal for visual
confirmation of spawning activity; however, none of the 17 potential spawning sites were
confirmed for spawning.
5.2.4.4. Pink Salmon
Of the 200 pink salmon tagged in the Middle River, 166 (83 percent) were classified by
destination (Table 5.2-1). Of these, 151 (91 percent) went to tributaries (primarily Indian or
Talkeetna rivers, and Portage, Fourth of July or Lane creeks; Figure D-7) and 15 (9 percent)
went to destinations in the mainstem Susitna River (Table 5.2-1; Figure 5.2-1; Figures D-5 and
D-6). The remaining 34 pink salmon, not able to be classified by a specific destination,
exhibited movements that prevented conclusive assignment to the mainstem or tributaries (Table
5.2-1).
Pink salmon were tracked to nine potential spawning sites in the Middle River (Table D-4;
Figure D-6). Each site was examined during mobile surveys (e.g., helicopter, boat, or HSC).
Sites where water conditions were too turbid for visual confirmation, an ARIS was used.
Spawning by pink salmon was confirmed at two sites, both were tributary delta habitats.
Holding behavior was observed at all sites, with the exception of Site 2. Fish observed in the
sonar imagery could not be identified to species, at potential spawning sites, but only holding or
migrating behavior were observed. Three sites had more than one tagged pink salmon detected,
but only one site (Site 8) had spawning confirmed. All spawning sites confirmed in 2013 were
also surveyed and spawning was confirmed in 2012.
5.2.4.5. Sockeye Salmon
Of the 137 sockeye salmon tagged in the Middle River, 92 (67 percent) were classified by
destination (Table 5.2-1). Of these, 44 (48 percent) went to tributaries (mainly Chulitna,
Talkeetna or Indian rivers, or Portage Creek; Figure D-7) and 48 (52 percent) went to
destinations in the mainstem Susitna River (Table 5.2-1; Figure 5.2-1; Figures D-11 and D-12).
The remaining 45 sockeye salmon, not able to be classified by a specific destination, exhibited
movements that prevented conclusive assignment to the mainstem or tributaries (Table 5.2-1).
Sockeye salmon were tracked to 13 potential spawning sites in the Middle River (Table D-5;
Figure D-12). Each site was examined during mobile surveys (e.g., helicopter, boat, or HSC).
ARIS was used at sites where water conditions were too turbid for visual confirmation. Seven of
the potential spawning sites had more than one tagged sockeye salmon detected, and three of the
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sites (Slough 8A, Slough 10, and Slough 11) included at least five fish. Spawning by sockeye
salmon was confirmed at six sites (four sloughs, one side channel, and one tributary delta).
Holding behavior was observed at all surveyed sites, except Site 1. Four sites with confirmed
spawning in 2013 (sloughs 8A, 9A and 11, and side channel 21) were also surveyed and
spawning was confirmed in 2012.
5.2.5. 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). These salmon appeared to have temporarily entered the Middle River in
the course of migrating to final spawning destinations elsewhere. The purpose of this behavior
was not clear, and was classified as roaming behavior. The proportions of salmon tagged at
Curry that exhibited this roaming behavior were 25 percent of large Chinook, 24 percent of small
Chinook, 61 percent of coho, 27 percent of chum, 29 percent of pink, and 29 percent of sockeye
salmon. Similarly, salmon tagged in the Lower River also showed this same behavior: these fish
migrated as far upstream as Lane Station (in the Middle River), then moved downstream into a
Lower River tributary. These were also roaming fish in the Middle River, but were evaluated
separately from fish tagged at Curry to discern any differences in roaming behavior between fish
tagged in the Lower River versus those tagged at Curry. The proportion of fish tagged in the
Lower River that exhibited this roaming behavior was 29 percent of Chinook salmon, 75 percent
of coho, and 10 percent of pink salmon. The proportion of radio-tagged fish exhibiting this
behavior in 2013 was greater than that observed in 2012, and this difference between years may
be due to proportionately larger returns to the Chulitna and Talkeetna rivers in 2013.
Some roaming fish moved far up into the Middle River before dropping back to enter
downstream tributaries (Table 5.2-3). One Chinook salmon (Fish 280) tagged at Curry on June
23 moved upstream to below Impediment 3 on July 13, and then dropped back to enter the
Talkeetna River on August 7.
5.3. Objective 3: Characterize adult salmon migration behavior and
timing within and above Devils Canyon
5.3.1. Species, Number, and Destination
Chinook salmon was the only species tracked above Impediment 1 (Table 5.3-1). Of the 445
radio-tagged large Chinook salmon released at the Curry fishwheels that were detected above
Gateway Station after tagging, 17 (3.8 percent) were tracked above Impediment 1, 13 (2.9
percent) above Impediment 2, and 3 (0.7 percent) above Impediment 3. Three of the Chinook
salmon radio-tagged and released in the Lower River mainstem were tracked above Impediment
2, neither of which passed Impediment 3 (Table 5.3-1). One small Chinook salmon passed
Impediment 1 (2.2 percent of the 45 small Chinook salmon that passed Gateway into the study
area).
The likely spawning areas for each of the 21 Chinook salmon that passed Impediment 1 are
provided in Table 5.3-2. Of the 3 Chinook salmon that passed Impediment 3, 1 (33 percent)
dropped back and likely spawned in a tributary downstream of Impediment 3 (Figures F-1 to
F-3). Of the 13 Chinook salmon that passed Impediment 2 but not Impediment 3, 9 (69 percent)
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dropped back and likely spawned in tributaries downstream of Impediment 2. Of the five
Chinook salmon that passed Impediment 1 but not Impediment 2, four (80 percent) dropped back
and likely spawned in a tributary downstream of Impediment 1. Overall, 67 percent of the
Chinook salmon that passed at least one of the three impediments likely spawned downstream of
the last impediment they passed – 36 percent (5 of 14) of these drop-back fish likely spawned in
Chinook Creek, and 29 percent (4 of 14) in Portage Creek.
The three Chinook salmon that passed Impediment 3 showed a wide range of movement-
distances and times (Figures F-1 to F-3). One Chinook salmon lived for 46 days after passing
Impediment 3. It travelled upstream in the mainstem Susitna River to PRM 309 before dropping
back below the impediments. The fish then spent three days in Portage Creek, followed by
movement farther downstream in the mainstem, downstream of Sunshine Creek (PRM 96; Table
5.3-1; Table F-1). The other two fish lived for less than 20 days after passing Impediment 3
(Table F-1): one headed straight for Devil Creek, and died in 14 days; and the other fish was
detected once near Deadman Creek, about 6.5 km (4.0 mi) beyond its eventual destination in
Tsusena Creek, then it held for six days below the confluence of Tsusena Creek, before entering
Tsusena Creek where it died after 11 days (Table F-1).
5.3.2. Migration Timing for Fish Passing Above Devils Canyon
The first successful fish passage past Impediment 1 occurred on June 30 when flows at the Gold
Creek and Tsusena Creek gages were 28,871 and 25,352 cubic feet per second (cfs), respectively
(Figure 5.3-1). No other fish passed until the period from July 11–17, when Tsusena Creek gage
flows declined to between 14,383 and 16,876 cfs. There was a period with no fish passage from
July 18 to 22 (in which flows exceeded 17,000 cfs at the Tsusena Creek gage), and then the final
passage event occurred on July 24 with Tsusena Creek flows at 16,884 cfs (Figure 5.3-1; Table
D-6).
The three Chinook salmon that passed Impediment 3 had passed Impediment 1 at the same
approximate period (July 11–13) as those that only passed Impediment 1 or Impediment 2 (Table
D-6).
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 3.8 days (Table D-6). Fish
moved more quickly past Impediment 2, with only one of the 16 radio-tagged Chinook salmon
holding below it for more than one day (Table D-6). Two fish that passed Impediment 1 did not
attempt to pass Impediment 2, rather they moved into and out of Cheechako Creek, and
eventually moved to their final destinations near Portage Creek. The three fish that passed
Impediment 3 held below it for an average of 6.5 days, whereas those that did not pass, held for
an average of 8.3 days before moving downstream. All of the fish that did not pass Impediment
3 were present above Impediment 2 from July 12 to 29, when all Impediment 3 passage events
occurred (Figure 5.3-2).
5.3.3. Relative Abundance of Salmon Passing Above Devils Canyon
Chinook salmon was the only species with radio-tagged fish detected upstream of Devils
Canyon. Of the 445 Chinook salmon tagged at Curry and detected moving above Gateway
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Station, three (0.7 percent) successfully migrated through all three impediments located in Devils
Canyon (Table 5.3-1). Given the extensive mobile survey effort, it is unlikely that any radio-
tagged fish passed upstream of Devils Canyon undetected.
5.3.4. Size of Chinook Salmon Tracked In and Above Devils Canyon
Of the 70 radio-tagged Chinook salmon that entered Devils Canyon, the mean body length of
fish that approached but did not pass Impediment 1 (70.1 cm [27.6 in]) was not significantly
different from that of fish that passed Impediment 1 (69.7 cm [27.4 in]; Table 5.3-1; t68 = 0.66,
P = 0.51). Similarly, the mean length of fish that approached, but did not pass, Impediment 2
(78 cm [30.7 in], n = 2) was not significantly different from that of fish that passed Impediment 2
(65.8 cm [25.9 in]; Table 5.3-1; t16 = 1.54, P = 0.14). The mean length of fish that approached,
but did not pass Impediment 3 (66.1 cm [26.0 in]) was not significantly different from that of
fish that passed Impediment 3 (64.3 cm [25.3 in]; n = 3; Table 5.3-1; t14 = 0.25, P = 0.81). These
observations are suggestive that length was not a factor in successful passage through Devils
Canyon for Chinook salmon.
5.3.5. Aerial Spawner Surveys
Chinook salmon were the only salmon species observed from Cheechako Creek upstream to the
Oshetna River. No adult salmon were observed in the mainstem Susitna River. 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, Fog,
and Tsusena creeks), and in one Upper River tributary (Kosina Creek; Figure D-13).
In streams were they had been determined to be present, adult Chinook salmon were not
consistently observed. They were documented in three streams during Survey 1, five during
Survey 2, three during Survey 3, four during Survey 4, and three during Survey 5 (Table D-7).
Cheechako Creek had the most Chinook salmon overall and was the only stream where Chinook
salmon were observed during all five surveys. Devil Creek had the second-highest number of
adult Chinook salmon, with significant numbers of fish present during the first four surveys. In
all other streams where adult Chinook salmon were observed, they were present in low numbers.
Peak observations for four of the streams occurred during the period of July 25–27, and during
the period of August 8–9 for two of the streams.
In Cheechako Creek, the number of Chinook salmon observed increased from five fish on July
21 to 40 fish on July 25. A steady decline in fish numbers was observed following the July 25
peak count, and by the final survey on August 15 only 1 fish was seen. Devil Creek followed a
similar trend with seven fish present during the first survey, peak count occurring on July 25, and
zero fish observed on the final survey. Cheechako and Devil creeks have similar geomorphology
consisting of high-gradient, step pools within steep-walled canyons. Chinook salmon habitat in
both streams terminates within three miles of the Susitna River confluence at large waterfalls.
The turbulent water and confined canyon walls presented challenges to salmon observation in
both streams. However, fish were observed throughout the anadromous reach of each stream and
groups of five to seven fish were seen holding in pools. Note that 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 peak survey.
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Chinook Creek, located between Cheechako and Devil creeks, had a much lower relative
abundance of Chinook salmon, with a peak observation of just two fish on July 25. Fish were
only observed during two of the five surveys. 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). However, fish were not
seen beyond 0.25 miles upstream of the Chinook Creek confluence with the Susitna River.
Low numbers of adult Chinook salmon were observed in Fog Creek. The lower reach of Fog
Creek is dominated by high-gradient riffle confined within a steep-walled canyon with no barrier
to Chinook salmon migration below 3,000 ft in elevation where the surveys terminated (at
approximately tributary river mile 20). 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 up to 3,000 ft in elevation.
One adult Chinook salmon was observed in Fog Creek during Survey 2 on July 25; no fish were
found on Survey 3; two fish were seen on Survey 4; and then a pair of fish was observed during
the final survey on August 15. The farthest upstream observation was approximately three miles
from the Fog Creek confluence with the Susitna River.
In Tsusena Creek, the next major tributary upriver from Fog Creek and the most upstream
tributary within the Middle River, a peak count of four Chinook salmon was obtained on
August 8. No fish were seen in Tsusena Creek prior to August 8, and then a pair of fish was
observed on August 15. The fish were distributed throughout the anadromous reach, which
terminates at a large waterfall at approximately tributary river mile 4.
Kosina Creek was the only tributary within the Upper River where adult Chinook salmon were
observed. Kosina Creek was the second largest tributary surveyed, and the lower reach was
dominated by moderate gradient, boulder riffle within multiple channels, and the upper reach
contained extensive shallow braided island complexes. During Survey 1 on July 21, one fish
was seen at approximately tributary river mile 1.5, and another fish was found near tributary
river mile 9. During Survey 2 on July 27, three fish were sighted near tributary river miles 11,
15, and 16. Although conditions were favorable for aerial observation, no fish were seen on
subsequent surveys.
Overall, weather conditions were favorable 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-8). Wind was the most influential weather factor, occasionally limiting the ability to
position the aircraft optimally above the stream, especially within canyons. 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. Water clarity, however, was a major factor
in the observation of fish, with turbidity from both glacial and erosion sources impairing surveys
in four streams. Overhanging vegetation, where present, completely obscured areas of stream
(Table D-9).
Overall, most streams had very clear water. The Black and Oshetna rivers were the only streams
of glacial origin within the study area and were the most turbid. Turbidity severely limited
visibility in the Black River and the Oshetna River downstream of the Black River confluence
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during all surveys. Visibility in Watana and Jay creeks was 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 erosion events upstream of the study area which reduced
visibility. The most prevalent impairment to visibility 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.
5.3.6. Assess the Feasibility of Using Sonar to Enumerate Salmon and
Resident Fish at the Proposed Dam Site
Results pertaining to the 2013 feasibility study are provided in Appendix G. The general
conclusion of that study was that sonar could be used to enumerate fish in the area, but more
work would be needed to determine the accuracy of such counts.
5.4. Objective 4: Use available technology to document salmon
spawning locations in turbid water
From July 24–31, 2013, 15 different sites were visited to assess Chinook salmon spawning
activity (Table 4.4-1), of which eight were surveyed using ARIS. Fish were observed at seven
sites, however, spawning activity (i.e., nest-guarding behavior) by Chinook salmon was only
observed at one site (Indian River Delta). At many sites it was difficult to distinguish Chinook
from chum salmon in the sonar images due to their overlap in length range. Several potential
spawning sites could not be accessed with a boat, while others were not suitable salmon
spawning habitat due to high water velocity, inappropriate substrate, or being located in the
thalwag of the river.
On July 31 and August 12, two potential spawning sites for chum salmon were sampled using
ARIS (Table 4.4-2). Chum salmon were observed at both sites, but spawning was only
confirmed at one of the sites. Confirmation of spawning with ARIS included nest-guarding
behavior and visible redds.
Seven HSC surveys were conducted from August 13 to September 2 (Table D-1). Locations
surveyed included historic spawning sites (see Section 5.5), potential spawning sites as indicated
from radio-telemetry analysis (see Section 5.2.3), and other sites that appeared suitable as
spawning habitat. Fifty-eight redds were sampled in slough and side-channel habitats, including
34 for chum, 6 for pink, and 18 for sockeye salmon. All data are reported by the Fish and
Aquatics Instream Flow Study (ISR Study 8.5).
5.5. Objective 5: Compare historical and current data on run timing,
distribution, relative abundance, and specific locations of
spawning and holding salmon
5.5.1. Run Timing
In 2013, Chinook salmon were captured at the Middle River fishwheels from June 16 to August
10. The midpoint of catches occurred on June 29, which was earlier than in 1982, 1985, and
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2012 (range: July 2–9), but later than the midpoints in 1981, 1983, and 1984 (range: June 24–
25). Peak catches in 2012 and 2013 occurred at the start of July (Figure A-13).
For chum salmon, the midpoint of catches at Curry in 2013 (August 5) was similar to those
observed from 1983 to 1985, and in 2012 (range: August 3–7), but earlier than those in 1981 and
1982 (range: August 12–17). Catches in 2012 and 2013 both peaked in early August (Figure
A-13).
The first coho salmon captured at the Middle River fishwheels in 2013 (July 23) occurred five
days earlier than in 2012 (July 28), but the midpoint of catches in both years occurred on August
15. In comparison, the midpoint of catches ranged from August 12–23 in the 1980s. The last
fish was captured on September 21, 2013; however, ARIS sonar data collected at Curry indicated
that coho salmon continued to migrate past Curry after September 21 (Figures A-17 and A-18).
Pink salmon moved past Curry from July 8 to September 4, 2013, with the midpoint of catches
occurring on August 3. The midpoint of catches in 2013 was later than in 1983 (August 1), but
earlier than in previous odd-numbered years (August 8 in 1981; August 5 in 1985).
The first sockeye salmon was caught at Curry on June 15, 2013, which was considerably earlier
than in years past (range: June 26–July 17), and the last fish was caught on September 10.
Catches in 2013 were relatively low and sporadic through July and August with no obvious peak.
The midpoint of catches in 2013 occurred on August 3, which was four days later than in 2012
(July 30), but in between the midpoints observed during the 1980s (range: August 1–7).
5.5.2. Relative Abundance
For all five species of salmon, catches of larger-sized fish at the Middle River fishwheels were
higher in 2013 than in 2012 (by 1.5–6.5 times). Changes in catch rates between these years were
largest for coho (1,711 in 2013; 264 in 2012) and pink (15,695 in 2013; 4,705 in 2012) salmon,
and smallest for Chinook salmon (616 in 2013; 422 in 2012). Approximately twice as many
chum (3,417 in 2013; 1,734 in 2012) and sockeye (176 in 2013; 92 in 2012) salmon were
captured in 2013 compared to 2012.
Catches of large Chinook and sockeye salmon in 2013 were 36 percent and 43 percent lower
than the average catches observed at the Curry fishwheels from 1981 to 1985, respectively. In
contrast, catches of chum, coho, and pink salmon in 2013 were roughly 2–8 times higher than the
average catches observed for these species in the 1980s. Interestingly, the number of pink
salmon captured in 2013 was substantially greater than catches observed during odd-numbered
years in the 1980s (range: 234–1,172), and similar to the highest catches observed in even-
numbered years (17,394 in 1984).
5.5.3. Spawning and Holding Salmon Locations
Potential spawning sites of Chinook, chum, coho, pink, and sockeye salmon in the mainstem
river were identified using radio telemetry (Sections 5.2.2 to 5.2.4) and HSC ground surveys.
Spawning sites were confirmed visually or with ARIS (sonar) for Chinook, chum, pink, and
sockeye salmon in the Middle River. Mainstem spawning occurred for chum, pink, and sockeye
salmon primarily in slough habitats, and to a lesser extent in tributary deltas and side channels.
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Most confirmed spawning sites in 2013 were also confirmed in 2012, and from 1981–1985
(Thompson et al. 1986; Table 5.5-1).
In 2013, radio-tagged Chinook salmon were tracked to eight potential spawning sites in the
Lower River (Figure D-2), and 13 sites in the Middle River (Figure D-8; see Sections 5.2.2 and
5.2.4). The only confirmed spawning site for Chinook salmon was Indian River delta (Middle
River). Similarly, tributary deltas were the only mainstem habitats confirmed for Chinook
salmon spawning during the 1980s surveys (Barrett et al. 1985; Thompson et al. 1986).
Chum salmon were tracked to no potential mainstem spawning sites in the Lower River (Figure
D-9) and nine sites in the Middle River in 2013 (Figure D-10; see Section 5.2.4). All confirmed
spawning sites in 2013 were previously confirmed sites from the 1980s or 2012 (Table 5.5-1;
Barrett et al. 1985; Thompson et al. 1986), with the exception of one unknown slough
(coordinates: N 62.58199, W 150.04903).
Coho salmon were tracked to 12 potential spawning sites in the Lower River (Figure D-3), and
17 sites in the Middle River (Figure D-4). Water clarity between October and ice-up was
suitable for visual confirmation of coho salmon spawning activity in mainstem habitats by aerial
telemetry crews; however, spawning was not confirmed at any of the potential spawning
locations indicated by radio-telemetry analysis.
In 2013, tagged pink salmon were tracked to twelve potential spawning sites in the Lower River
(Figure D-5), and nine sites in the Middle River (Figure D-6; see Sections 5.2.2 and 5.2.4). All
confirmed spawning sites in 2013 were previously confirmed as spawning sites during the 1980s
or in 2012 (Table 5.5-1; Barrett et al. 1985; Thompson et al. 1986).
Sockeye salmon were tracked to three potential spawning sites in the Lower River (Figure D-11),
and 13 sites in the Middle River (Figure D-12; see Section 5.2.4). All confirmed sloughs, side
channel 21, and Skull Creek were previously confirmed as spawning sites during the 1980s or in
2012 (Table 5.5-1; Barrett et al. 1985; Thompson et al. 1986).
5.6. Objective 6: Generate counts of adult Chinook salmon
spawning in the Susitna River and its tributaries
5.6.1. Observer Efficiency During Aerial Spawner Surveys
On July 25, 363 live Chinook salmon were counted above the Indian River weir during an aerial
spawner survey conducted by AEA (2-person crew; Tables 4.3-1, D-8, and H-1; Figure D-13).
During a concurrent survey conducted by ADF&G (1-person crew), 281 live Chinook salmon
were counted above the weir (Table H-1; Sam Ivey, ADF&G, Sport Fish Division, personal
communication). The net passage of Chinook salmon above the weir on July 25 was 1,094 fish
(all sizes combined; Tables B-4 and H-1; Figure B-2). The same day, 71.7 percent (43 of 60) of
all radio-tagged Chinook salmon last detected upstream of the weir were emitting a ‘live’ signal.
Based on this proportion, an estimated 784 (71.7 percent of 1,094) live Chinook salmon were
located above the weir at the time of the aerial spawner surveys. Therefore, assuming only live
fish were available to count during aerial spawner surveys, the estimated observer efficiency
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during the AEA survey was 46.3 percent, which was considerably higher than during the
ADF&G survey (35.8 percent; Table H-1).
5.6.2. Chinook Salmon Mark Rates: Indian River vs. Portage Creek
On July 25, 868 live Chinook salmon were counted during an aerial spawner survey of Portage
Creek conducted by ADF&G (S. Ivey, personal communication). If it is assumed that the
observer efficiency on the Portage Creek survey was the same as that on ADF&G’s Indian River
survey (35.8 percent; Table H-1), then the adjusted number of live Chinook salmon in Portage
Creek on July 25 was 2,425. The same day, 174 (84.5 percent) of the radio-tagged Chinook
salmon released at the Middle River fishwheels were last detected alive in Portage Creek.
Therefore, the estimated mark rate for live fish in Portage Creek was 7.2 percent (174 of 2,425),
which was statistically similar to the overall mark rate in Indian River (6.3 percent; χ2 = 0.9, df =
1, P = 0.36). These results support the hypothesis that Chinook salmon had an equal probability
of being tagged at the Middle River fishwheels, regardless of their spawning location.
5.6.3. Estimated Abundance Above Curry (Chinook, Chum, and Pink Salmon)
Two-sample mark-recapture methods were used to estimate the inriver abundance of large
Chinook, pink, and chum salmon above the Middle River Gateway fixed station (PRM 130.1) in
2013.
5.6.3.1. Chinook Salmon
A total of 536 large Chinook salmon were radio-tagged at the Middle River fishwheels, of which
445 (83.0 percent) entered the study area (i.e., were detected at or above the Middle River
Gateway fixed station; Tables H-2 and H-3). At the Indian River weir, 1,137 large Chinook
salmon were inspected for tags from June 26 to August 20, of which 72 (6.3 percent) were radio-
tagged (Table H-2). The first two tagged large Chinook salmon passed the weir on June 28
(released on June 18 and 19 at Curry), and the last radio-tagged fish passed the weir on August 5
(released July 16 at Curry). Mark rates at the weir varied significantly across statistical weeks
(χ2 = 12.1, df = 5, P = 0.03); however, weekly recapture rates were similar (χ2 = 6.3, df = 4, P =
0.18). These results indicated that no stratification by time was required to estimate abundance.
Using a modified Petersen estimator, an estimated 6,952 large Chinook salmon (SE = 782; 95%
confidence interval [CI] = 5,536–8,724) passed the Middle River Gateway fixed station from
June 18 to July 28 (Table H-3).
5.6.3.2. Chum Salmon
Of the 201 chum salmon radio-tagged at the Middle River fishwheels, 149 (74.1 percent) entered
the study area (Tables H-3 and H-4). Weekly proportions (range: 0.4–1.0) of radio-tagged chum
salmon that entered the study area were used to estimate the number of spaghetti-tagged fish that
entered the study area (1,365, or 69.6 percent of the 1,962 spaghetti tags applied; Table I-3).
Since spaghetti-tagged chum (and pink) salmon were not uniquely identifiable at the Indian
River weir, only radio-tagged fish could be used to evaluate whether mark and recapture rates
varied over time. Similar to Chinook salmon, mark rates for radio-tagged chum salmon varied
across statistical weeks (χ2 = 11.6, df = 3, P = 0.01), and weekly recapture rates were similar
(χ2 = 7.4, df = 3, P = 0.06; Table H-4). By pooling all tagged fish, an estimated 36,010 chum
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salmon (SE = 1,511; 95% CI = 33,108–39,166) passed the Middle River Gateway fixed station
from July 13 to August 24 (Table H-3).
5.6.3.3. Pink Salmon
In total, 151 (75.5 percent) of the pink salmon radio-tagged at the Middle River fishwheels
entered the study area (Tables H-3 and H-5). Of the 9,108 spaghetti-tagged pink salmon released
at the Middle River fishwheels, 6,736 were estimated to have entered the study area (Table H-3).
Similar to Chinook and chum salmon, mark rates for radio-tagged pink salmon varied by
statistical week (χ2 = 9.9, df = 3, P = 0.02), and weekly recapture rates were similar (χ2 = 3.6, df
= 3, P = 0.30; Table H-5). Using both radio- and spaghetti-tagged fish in the marked sample, an
estimated 127,353 pink salmon (SE = 2,761; 95% CI = 121,909–133,041) passed the Middle
River Gateway fixed station from July 8 to August 16 (Table H-3).
5.6.4. Estimated Abundance Above Devils Canyon (Chinook Salmon)
Too few tagged and untagged Chinook salmon were observed above Devils Canyon to develop
statistically precise estimates. Two different approaches were used to estimate the abundance of
Chinook salmon above Devils Canyon (i.e., above Impediment 3). The first approach involved
expanding the peak aerial count by the estimated observer efficiency during the spawner surveys.
In 2013, the peak count of live Chinook salmon (all sizes combined) above Devils Canyon was
29 fish (25 in Devil Creek, 1 in Fog Creek, and 3 in Kosina Creek), which was obtained during
the aerial spawner survey conducted from July 25–27 (Table D-7). If this number (29) is
expanded based on an observer efficiency of 46.3 percent, which was obtained during the AEA
aerial spawner survey in Indian River (Table H-1), then 63 live Chinook salmon were estimated
to have been above Devils Canyon at the time of the survey. This would be considered a
minimum number as the visibility of Chinook salmon during aerial surveys is better in Indian
River than some of the tributaries above Devils Canyon.
The second approach involved expanding the number of radio-tagged Chinook salmon detected
above Devils Canyon by the marked fraction of Chinook salmon in the Middle River. Of the 445
radio-tagged large Chinook salmon that entered the study area in 2013, three (0.7 percent) were
detected above Devils Canyon (Table 5.2-1). If AEA expands these three radio-tagged fish by
the estimated marked fraction of large Chinook salmon (6.3 percent, or each tagged fish
represented at total of approximately 15.9 fish), then it can be inferred that 48 large Chinook
salmon migrated above Devils Canyon in 2013. As a sensitivity analysis of an extreme but
unlikely event, if four or five radio-tagged large Chinook salmon had actually migrated above
Impediment 3 in 2013, then the expanded counts would have been 63 or 79 fish, respectively.
5.7. Objective 7: Collect tissue samples to support the Fish
Genetics Study
Genetic samples were collected from 609 Chinook (small and large fish combined), 201 chum,
220 coho, 199 pink, and 138 sockeye salmon captured at the Middle River fishwheels (Table A-
4). Genetic samples were also collected from Arctic grayling (40), burbot (1), Dolly Varden
(11), longnose sucker (5), rainbow trout (33), round whitefish (56), and humpback whitefish (10;
Table A-4). In the Lower River, genetic samples were collected from 699 Chinook, 596 coho,
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and 200 pink salmon. Genetic samples were also collected from 691 Chinook salmon in the
Yentna River and 200 coho salmon in Montana Creek.
All genetic tissue samples were delivered to Alaska Department of Fish and Game’s (ADF&G’s)
Gene Conservation Lab for analysis. Results are reported in the ISR for the Genetic Baseline
Study for Selected Fish Species (ISR Study 9.14).
5.8. Objective 8: Estimate the system-wide Chinook and coho
salmon escapement to the Susitna River above Yentna River
and the distribution of those fish among tributaries of the
Susitna River
Results pertaining to Objective 8 are provided in Appendix I. This portion of Study 9.7 was
carried out by ADF&G.
6. DISCUSSION
6.1. Fish Capture and Tagging
6.1.1. Catch Rates
Ice-out in the Susitna River in 2013 was among the latest ever, approximately two weeks later
than normal. In the Lower River, fish capture started on May 25 in 2012, but not until June 4 in
2013. By June 4 in 2012, 469 Chinook salmon had been captured. The total catch of 2,063
Chinook salmon in 2013 was very similar to the total catch of 1,916 fish in 2012 in the Lower
River.
This was the first year of sampling Chinook salmon on the Yentna River at tributary river mile 6.
While the 2,295 Chinook salmon captured in all gear types combined exceeded the radio-tagging
goal of 700 fish, the north bank fishwheel had chronically low catches. To achieve the radio-
tagging goal, tags scheduled for the north bank fishwheel were instead deployed on gillnet-
caught fish.
In the Middle River, catches of all five species of salmon were higher in 2013 than they were in
2012 (1.7, 2.0, 2.1, 3.3, and 6.5 times higher, respectively, for Chinook, chum, sockeye, pink,
and coho salmon). Even when catches at the Site 3 fishwheel (added in 2013) were excluded,
catch rates in 2013 were still higher than those in 2012, with the exception of pink salmon.
Similar to 2012, high catches at the Middle River fishwheels in 2013 were due largely to the
physical characteristics of the sites, design and operation of the fishwheels, and use of leads.
Sites 1 and 2 were protected from floating debris at low to moderate river discharges, yet for
most of the season these sites had sufficiently high water velocities offshore to force fish against
the bank and into the path of the fishwheels (2–3 m/s [6.6–9.8 ft/s] offshore of the outer
fishwheel pontoon). These were undoubtedly the same characteristics that made these sites
attractive to ADF&G biologists during the 1980s studies. However in 2013, river velocities and
depths for a given discharge at sites 1 and 2 had changed significantly since the 2012 season, due
to an apparent shift in channel morphology. These changes made it difficult to operate the Site 1
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fishwheel when river discharge decreased below around 17,500 cfs. As a result, the new site
(Site 3) was located upstream of Curry, where a third fishwheel could be operated effectively at
lower discharges. Although Site 3 was more exposed to floating debris, it proved very effective
at capturing fish across a range of late-summer discharges.
Again, similar to 2012, lead nets hung between the shore-side pontoons of the Middle River
fishwheels and the adjacent riverbank also contributed to higher catch rates in 2013, particularly
at Site 1 where the fishwheel was held up to 50 ft offshore with spar poles. ARIS imagery from
Site 1 showed that the vast majority of fish migrated upstream within 13 m (43 ft) of shore, so
without the lead net these fish would not have been directed offshore and into the path of the
fishwheel.
In the Middle River, radio-tagging goals were easily met for chum, coho, and pink salmon, but
were not met for Chinook (96 percent of target) or sockeye (70 percent of target) salmon. Due to
the unexpectedly high catches of chum, coho, and pink salmon, a disproportionately large
number of radio tags were deployed on the early components of these runs relative to the later
components.
6.1.2. Use of ARIS to Assess Fishwheel Effectiveness and Fish Approach
Behavior
The use of ARIS at Site 1 in the Middle River, to assess fishwheel effectiveness and fish
approach behavior, was most valuable in June and September. In June, ARIS data confirmed
that the leading edge of the Chinook salmon run was being covered by fishwheel effort. The
ARIS data also assisted with placement of the lead net at the Site 1 fishwheel. In September, the
ARIS data was useful for quantifying the relative abundance of passing coho salmon, particularly
when water levels and turbidity decreased and the fishwheel could not be operated effectively or
at all at Site 1. Under these river conditions, ARIS counts in September could be useful for
informing coho salmon tag rates for an alternative capture method at Curry (e.g., beach seine).
Information on diel pattern obtained from ARIS data was useful for informing the crew as to the
best times to operate the fishwheels in order to achieve optimal catch rates.
ARIS data at Site 1 was less useful in July and August when a large number of fish, as well as
multiple species of salmon, began migrating through the Middle River. When large numbers of
fish were passing, it took a substantial amount of effort to review the ARIS imagery, and the data
was only marginally useful to guide fishwheel and tagging operations. Outside of large Chinook
salmon, fish observed in the ARIS imagery could not be identified by species.
6.1.3. Size Selectivity
Achieving the goals of this study was dependent on tagging a representative group of fish from
the entire population. The size composition of tagged fish compared to the entire population was
examined in this regard. Tagging particular stocks and/or sizes of fish at different rates than
others might weaken inferences about habitat uses of the Lower, Middle, and Upper rivers, such
as the relative distribution of spawning fish, migratory behavior, and any fish passage above
Devils Canyon. 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-
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sized Chinook salmon compared to 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
(1983) 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. Species selectivity may also be a function of fish size,
as there is 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 (ADF&G 1983;
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 velocities force
fish to migrate near shore (Link and Nass 1999). Based on the experience of the study team, the
Curry sites were characterized as generally high gradient, and similar to locations where the least
size selectivity in fishwheels was encountered.
Radio-tagging of Chinook and coho salmon at the Lower River site and Chinook salmon in the
Yentna River was conducted within the framework of a mark-recapture experiment. This
approach provided for the use of robust diagnostic tools to evaluate assumptions of equal
probability of capture (Seber 1982) during both radio-tagging and second event sampling at weir
sites. When heterogeneity in probability of capture is detected, the results of diagnostics tests
provide specific for selecting the proper models to minimize or eliminate biases due to unequal
probability of capture when estimating abundance. These same tools are used to minimize or
eliminate bias in estimates of numbers of spawners in different tributaries when heterogeneity in
probability of capture is detected during marking.
Size selective sampling was detected for Chinook salmon radio-tagged at the Lower River site
when tagging was conducted using a combination of fishwheels and drift gillnets for sampling.
The gillnet sampling was conducted to increase the probability of capture for larger Chinook
salmon, as it was expected that fishwheels would provide biased samples favoring smaller fish at
that site. Additionally, Chinook salmon <58cm were radio-tagged at approximately 1/3 the rate
of larger fish based on the analysis of data from Chinook salmon tagged in 2012 that passed the
Deshka River weir site. These measures were not sufficient to eliminate heterogeneity in
probability of capture by size for the combined sample of radio-tagged fish. However, analysis
of data from these radio-tagged fish in the framework of a mark-recapture experiment provided
minimally biased estimates in the distribution of spawning Chinook salmon among tributaries of
the Susitna River above the Lower River site.
Size selective sampling was detected for coho salmon radio-tagged at the Lower River site where
tagging was conducted using 2 fishwheels situated on opposing banks of the river. While the
fishwheels were effective in capturing all sizes of coho salmon present, diagnostic test results
indicated the fishwheels were biased in favor of smaller coho salmon. Similar to the Chinook
salmon experiment, analysis of data from these radio-tagged fish in the framework of a mark-
recapture experiment provided minimally biased estimates in the distribution of spawning coho
salmon among tributaries of the Susitna River above the Lower River site.
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In 2013, radio-tagged small Chinook, chum, and pink salmon tended to be slightly larger than
those fish captured at all Middle River fishwheel sites. For smaller-sized Chinook and pink
salmon in particular, this was likely due to the fact that the radio tags would simply not fit into
their stomachs. This was reflected in the fact that spaghetti-tagged chum, coho, and pink
salmon, for which the tag is just as easily inserted in small and large fish, were similar in length
to those fish captured. To avoid this potential source of bias, some more appropriately sized
radio tags should be purchased to accommodate the full range of fish lengths likely to be
encountered for each species.
No evidence of size selectivity at the Middle River fishwheels was detected for radio-tagged
large Chinook salmon or spaghetti-tagged pink salmon when samples collected at the Indian
River weir were used for comparison. There was evidence to suggest some size-selective
spaghetti-tagging occurred for chum salmon; however, due to large sample sizes it was possible
that the KS tests were detecting small differences between length-frequency distributions which
have little potential to result in bias (e.g., during escapement estimation).
6.2. Use of Tributary Weirs (and Sonar) to Assess Numbers and
Size of Marked and Unmarked Fish
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 salmon mark-recapture experiment. While size biased
sampling was detected when using only these two sites for second event sampling, substantial
numbers of all size classes of Chinook salmon in the mainstem Susitna River are detected at
these sites. As such, capture heterogeneity can be detected and the appropriate remedial measure
applied to minimize bias when estimating abundance and distribution of spawning Chinook
salmon. Radio-tagged Chinook salmon that were recaptured at these sites were tagged across the
entire time-frame of the marking event, ensuring a non-zero probability of capture for Chinook
salmon tagged both early and late in the run of Chinook salmon passed 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.
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 coho salmon mark-recapture experiment. No size biased sampling was
detected when using only these two sites for second event sampling, indicating that the size
distribution of coho salmon spawning above these to weir sites is similar to, at least in
combination, to the size distribution of all coho salmon spawning above the Lower River tagging
site. Radio-tagged coho salmon that were recaptured at these sites were tagged across the entire
time-frame of the marking event, ensuring a non-zero probability of capture for coho salmon
tagged both early and late in the run of Chinook salmon passed 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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6.2.1. Indian River Weir
Mark rates for fish inspected at the Indian River weir that were tagged in the Middle River were
highest for large Chinook salmon (6.3 percent), followed by small Chinook (4.4 percent), coho
(3.3 percent), sockeye (2.5 percent), chum (0.4 percent), and pink (0.1 percent) salmon. Mark
rates for Chinook, chum, and pink salmon were considered reliable for accuracy and precision
with respect to estimating abundance. A few minor issues had the potential to introduce
uncertainty into these mark-rate estimates (e.g., detection efficiency at the fixed-station receiver
at the weir was less than 100 percent); however, given the short amount of time when video
imagery was not being collected in 2013, and the fact that aerial telemetry surveys were
conducted regularly, these issues had an inconsequential effect on the mark-rate estimates for
any species.
The results of size-selectivity tests using fish sampled at the Indian River weir should be viewed
with caution, as some uncertainty exists. Length measurements collected from video imagery at
the Indian River weir were less precise than those collected from fish that were physically
handled, for a variety of reasons. Also, since fork lengths were collected at the weir, they had to
be converted to mid-eye to fork lengths in order to make them comparable to the length
measurements collected at the Middle River fishwheels. Regression equations, established
during the 2012 study, were used to do this. The degree of bias introduced by this methodology
was not quantified, but it was likely inconsequential to the results. Also, our overall conclusions
about the degree or presence of size selectivity are relatively robust to imprecision.
6.3. Migration Behavior and Spawning Locations of Salmon in the
Lower, Middle, and Upper Susitna River
6.3.1. Lower River
The tracking results for salmon tagged in the Lower River indicated that at least 49 percent of the
pink salmon and 90 percent of the Chinook salmon likely spawned in tributaries (Figure 5.2-1).
Due to the high proportion of Chinook salmon that returned to tributaries, only four potential
mainstem spawning locations were identified in the Lower River, all near the Deshka River and
Willow Creek mouths (Figure D-2). Two additional possible mainstem sites were identified
based on the behaviors of Chinook salmon tagged in the Middle River (Figure D-2). In contrast,
many potential mainstem spawning sites were identified for pink salmon, located throughout the
Lower River from the confluence of the Yentna River up to the Caswell Creek area, and between
Sunshine and Whiskers creeks (Figure D-5). However, it should be noted that these results were
likely biased towards an over-abundance of potential mainstem spawning sites. The bias exists
because insufficient effort was made to track pink salmon during aerial telemetry surveys of the
tributaries in the Lower River. Due to inadequate tributary coverage for this species, pink
salmon classifications were biased away from tributary designations, thus creating the
appearance of a higher proportion of mainstem spawning. This bias must be kept in mind when
drawing conclusions about pink salmon spawning in the Lower River mainstem.
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6.3.2. Middle and Upper River
The tracking results for Chinook (small and large fish combined), chum, and pink salmon radio-
tagged in the Middle River indicated that 73–77 percent of these fish likely spawned in
tributaries (Figure 5.2-1). Nevertheless, the number of radio tags applied to these fish (200–603
per species) was adequate to identify several potential mainstem spawning locations in the
Middle River (9–13 locations, depending on the species). For sockeye salmon, 13 potential
spawning locations were located in the Middle River; sockeye salmon did not show the same
preference for tributary spawning as was observed for the other salmon species (Figure 5.2-1).
Of particular interest was Slough 8A, near which 15 spawning sockeye salmon were classified
(Figure D-12), including 13 fish in the slough itself (Table 5.2-1). This number represents 11
percent of the total number of sockeye salmon tagged, 16 percent of the number that were
successfully classified, and 31 percent of the total number that were classified with mainstem
destinations. No radio-tagged fish were tracked to potential mainstem, slough, or side-channel
locations in the Upper River.
The frequent aerial telemetry surveys conducted on the Middle River, 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 us to identify those fish
that were likely holding and/or spawning in mainstem habitats. There was a high degree of
consistency between the potential spawning sites identified for radio-tagged chum and sockeye
salmon in 2013, 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.
6.4. Salmon Migration Behavior and Timing Within and Above
Devils Canyon
In 2013, only three radio-tagged fish (all Chinook salmon) passed Devils Canyon, which was
down from the 12 tagged fish in 2012, even though more fish were tagged in 2013 than in 2012
(536 large Chinook salmon radio-tagged in 2013 versus 352 in 2012). Two of the three Chinook
salmon in 2013 (Fish 272 and 395) headed almost directly to the their destination tributary (Fish
395 made a 6.5 km [4 mi] overshoot for approximately 1 day). In contrast, the third Chinook
salmon in 2013 (Fish 241) showed considerable pre-spawning movements. This third fish
moved more than 200 km (124 mi) beyond Devils Canyon to an area near the Susitna headwaters
(PRM 309), before moving back downstream and spending three days in Portage Creek among
other spawning fish. None of the 12 tagged fish above Devils Canyon in 2012 exhibited this
degree of pre-spawn wandering (AEA 2013). This behavior suggests some interesting
exploratory behavior, but with a sample of three tagged fish, it is difficult to characterize the
relative significance of this wandering behavior to all fish above Devils Canyon.
In 2013, there was evidence suggestive of Chinook salmon spawning upstream of Devils
Canyon. This was consistent with the results from surveys conducted in previous years. For
example, a few Chinook salmon (20–45 fish) were observed in tributaries above Devils Canyon
in 1982–1983 (AEA 2011). In 1984, Chinook salmon spawning was observed in Chinook (n =
15) and Fog (n = 2) creeks. In 2003, juvenile Chinook salmon were sampled in Fog Creek,
Kosina Creek, and as far upstream as the mouth of the Oshetna River; adult Chinook salmon
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were also documented in the Upper River (Buckwalter 2011). In 2012, radio-tagged Chinook
salmon were detected and appeared to spawn in Kosina and Devil creeks (AEA 2013). Thus, the
2013 results add to the body of knowledge about the distribution and abundance of salmon
spawning above Devils Canyon (see AEA 2011).
In 2012, there were results to suggest that fish length and river flow rates influenced passage
success through Devils Canyon (AEA 2013). In 2013, there was no effect of fish length on
passage success, but results similarly suggest that passage was minimal when Susitna River
flows were greater than 17,000 cfs (as measured near Tsusena Creek). Similar to 2012, our
results were fairly 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 difficult to quantify. Of particular concern is the potential
confounding effects of “time of year.” Since, in both years, fish moved above the final
impediment during lower-flow periods that occurred at around the same timeframe (July 17–20
in 2012 and July 13–30 in 2013), it is difficult to quantify the relative importance of flows versus
time of year. In both years, there were Chinook salmon that approached Impediment 3 during
periods of higher flows, in the latter half of July, and did not pass Impediment 3. In 2012, flows
increased substantially after July 20 and remained above the 19,000 cfs level at Gold Creek
through August 7 (AEA 2013). This flow at Gold Creek was roughly equivalent to 15,800 cfs at
Tsusena Creek in 2012. In 2013, flows measured at Tsusena Creek increased after the second
fish passed Impediment 3 on July 16 and remained above 16,500 cfs until late July. While four
Chinook salmon that approached Impediment 3 after July 16 in 2013, only one of these fish
passed Impediment 3. This was the only fish that held below Impediment 3 until July 28–29,
when flows dropped below 16,500 cfs (Figure 5.3-1). This last Chinook salmon that passed
Impediment 3 was detected upstream of Impediment 3 on July 30, and likely passed Impediment
3 at flows below 16,000 cfs on July 29, prior to the increase in flow to over 18,500 cfs on July
30. The rapid changes in flow over a 24-hour period observed in late July in 2012 and 2013
emphasize the benefits of having fixed-station receivers near each impediment to determine the
precise timing of fish passage and assess the relationship between passage and flow levels.
6.5. Use of ARIS to Document Spawning Locations in Turbid Water
ARIS was used successfully to confirm spawning behavior was confirmed for two species
(Chinook and chum salmon) at two separate locations (Indian River, and Fourth of July side
channel).; however, the limitations of ARIS should be considered before further surveys are
conducted in the next year of study. These limitations were identified at a site where spawning
by chum salmon was confirmed visually during times of decreased turbidity. Of particular
concern is the use of ARIS to characterize spawning activity in shallow water and close to the
shoreline.
The equipment required to operate the ARIS is heavy and required a boat with a suitable gunnel-
mount. To obtain the needed resolution and stability, the boat and sonar had to be positioned
next to the shoreline; however, most spawning activity, with the exception of Chinook salmon,
occurred in close proximity to the shoreline (10–15 ft). Chinook salmon (e.g., those confirmed
spawning at Indian River delta) typically spawned farther offshore compared to observations for
other salmon species. Shoreline-spawning made data collection with ARIS difficult, because the
noise associated with the activity and the close proximity of the boat often spooked the target
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fish. Up to 20 minutes was required for the target fish to return to the original locations and
continue pre-disturbance activities. In some cases, the target fish did not return until after the
boat was moved.
Another issue with the ARIS was related to detecting redds’ construction. In many instances,
due to the slope of the substrate and the orientation of redd depressions, redds could not be
visualized in the sonar images. However, fish could be seen on the sonar holding and displaying
nest-guarding behavior. Redd digging was not captured on the sonar despite several hours of
footage covering fish that could be visually observed constructing redds. When fish swam into a
redd depression (e.g., to dig), they could not be detected by the sonar. In addition, when a fish
was not perpendicular to the sonar beam, its signal became weak and made behavioral
observations of fish traveling toward or away from the sonar difficult.
Many of the potential spawning locations indicated by radio telemetry could not be accessed
safely by boat, and thus could not be sampled with ARIS. As indicated above, the weight of the
ARIS equipment precluded a smaller, more mobile platform. However, sites that were
inaccessible by boat were also typically too shallow to sample with ARIS.
It is worth noting that many locations considered inaccessible by boat were later confirmed as
spawning sites for chum and sockeye salmon during aerial and HSC surveys (Study 8.5). Most
turbid water sites identified as potential spawning locations for chum and sockeye salmon using
telemetry were in areas that were eventually isolated from the turbid mainstem water and became
clear; or the turbid water became clear due to decreased glacial input later in the season. As
such, sonar confirmation of potential spawning by chum and sockeye salmon should be a lower
priority than Chinook salmon, because Chinook salmon have a spawning window entirely within
a period when the Middle River discharge and turbidity are generally high.
At sites where multiple fish species with a large degree of overlap in body length could be
present, ARIS was not able to positively identify species. This issue was most obvious during
the spawning period for chum, pink, sockeye, and coho salmon, and was further complicated due
to the relatively high abundance of chum and pink salmon in 2013. This is much less of an issue
with Chinook salmon, which spawn, in part, during a period when few other species are present,
and they are typically much larger than most other salmon species.
6.6. Estimated Abundance of Chinook Salmon Above Devils
Canyon
Given the large number of Chinook salmon that the mark rate was based on, the approach of
estimating abundance by expanding the number of radio tags detected above Devils Canyon was
a more robust approach than expanding the peak count from aerial spawner surveys. In any
event, the two independent estimates were remarkably similar, and regardless of the approach
used, it could be concluded that roughly 50–65 Chinook salmon migrated above Devils Canyon
in 2013. No fewer than 29 fish migrated above Devils Canyon (i.e., the minimum aerial count).
To conclude that 100 fish moved above Devil Canyon in 2013 would require that the mark rate
on fish above Devils Canyon was half (i.e., 1 in 33 fish) that observed in 1,137 fish examined at
the Indian River weir (1 in 16) – although a possibility, this was statistically unlikely.
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6.7. Study Interdependencies
Four Project studies provided predecessor information useful to the Salmon Escapement Study.
The Upper River Fish Distribution and Abundance Study (ISR Study 9.5), and Middle and
Lower River Fish Distribution and Abundance Study (ISR Study 9.6) provided salmon
distribution and abundance information from aerial telemetry surveys that was useful for
determining spawning locations (Objective 1) and estimating Chinook salmon escapement and
relative distribution among tributaries (Objective 8). The Characterization and Mapping of
Aquatic Habitats Study (ISR Study 9.9) provided habitat characterization information useful for
describing spawning locations visited as part of turbid water and visual confirmation of
spawning surveys (Objective 2). The Fish Genetic Baseline Study (ISR Study 9.14) provided
information on Chinook salmon spawning locations (Objective 1) from sample collections
conducted in 2012. The Salmon Escapement Study, along with the Upper River Fish
Distribution Study (ISR Study 9.5), and Middle and Lower River Fish Distribution Study (ISR
Study 9.6), provided genetic tissue samples for the Genetic Baseline Study (ISR Study 9.14).
The Salmon Escapement Study also interrelates with other Project studies and provided useful
output information in 2013. Weekly updates were provided via email to the various study leads
that contained inseason information on the Salmon Escapement Study (e.g., Curry fishwheel
catches, Indian River weir counts, and distribution of radio-tagged fish). These data provided
guidance to potential spawning locations where the Genetics Baseline Study (ISR Study 9.14)
might collect samples and the Instream Flow Study (Study 8.5) might collect Habitat Suitability
Criteria data for redds. The Salmon Escapement Study provided extensive opportunity to collect
fixed and mobile telemetry data for resident fish radio-tagged as part of the Upper River Fish
Distribution and Abundance Study (ISR Study 9.5), and Middle and Lower River Fish
Distribution and Abundance Study (ISR Study 9.6), and also provided catch from the fishwheels
for tagging. Characterizations of migration behavior and spawning locations (Objective 2), and
fish movement in and upstream of Devils Canyon (Objective 3) were provided to the Fish
Passage Feasibility Study (ISR Study 9.11) and were used to inform target species, timing and
location of potential passage alternatives.
7. COMPLETING THE STUDY
[Section 7 appears in the Part C section of this ISR.]
8. LITERATURE CITED
Alaska Energy Authority (AEA). 2011. Aquatic Resources Data Gap Analysis. Draft.
Prepared for Alaska Energy Authority, July 20, 2011.
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.
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page 56 June 2014
AEA. 2013. Adult Salmon Distribution and Habitat Utilization Study. Susitna-Watana
Hydroelectric Project, FERC Project No. 14241. February 2013. Anchorage, Alaska.
http://www.susitna-watanahydro.org/wp-content/uploads/2013/03/Attachment-A-AS.pdf
Alaska Department of Fish and Game (ADF&G). 1983. Phase 2 draft report. Volume 1.
Synopsis of the 1982 aquatic studies and analysis of fish and habitat relationships.
Appendices. Alaska Department of Fish and Game, Susitna Hydro Aquatic Studies,
Anchorage, Alaska.
Barrett, B.M., F.M. Thompson, and S.N. Wick. 1985. Adult salmon investigations: May–
October, 1984. Report No. 6. Alaska Department of Fish and Game, Susitna Hydro
Aquatic Studies, Anchorage, Alaska.
Buckland, S.T. and P.H. Garthwaite. 1991. Quantifying precision of mark-recapture estimates
using bootstrap and related methods. Biometrics 47:255-268.
Buckwalter, J.D. 2011. Synopsis of ADF&G’s Upper Susitna Drainage Fish Inventory, August
2011. November 22, 2011. Alaska Department of Fish and Game, Division of Sport
Fish, Anchorage, AK. 173 pp.
Chapman, D.G. 1951. Some properties of the hypergeometric distribution with applications to
zoological censuses. University of California Publication Station 1:131-160.
Cleary P.M., R.A. Merizon, R.J. Yanusz, and, D.J. Reed. 2013. Abundance and Spawning
Distribution of Susitna River chum Oncorhynchus keta and coho O. kisutch salmon,
2010. Alaska Department of Fish and Game, Fishery Data Series No. 13-05, Anchorage.
Darroch, J.N. 1961. Two-sample capture-recapture census when tagging and sampling are
stratified. Biometrika 48: 241-60.
Efron, B.I. and R.J. Tibshirani. 1993. An introduction to the bootstrap. Chapman and Hall.
New York.
Federal Energy Regulatory Commission (FERC), Office of Energy Projects. 2013. Study Plan
Determination for the Susitna-Watana Hydroelectric Project. Federal Energy Regulatory
Commission, Washington, D.C. Issuance: 20130201-3041.
Groot, C. and L. Margolis. 1991. Pacific salmon life histories. UBC Press, Vancouver, BC, 564
pp.
Hughes, N.F. 2004. The wave-drag hypothesis: an explanation for size-based lateral segregation
during the upstream migration of salmonids. Canadian Journal of Fisheries and Aquatic
Sciences 61: 103-109.
Link, M.R., and B.L. Nass. 1999. Estimated abundance of Chinook salmon returning to the
Nass River, B.C., 1997. Canadian Manuscript Report of Fisheries and Aquatic Sciences
2475: xi + 64.
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Page 57 June 2014
Meehan, W.R. 1961. The use of a fishwheel in salmon research and management. Transactions
of the American Fisheries Society 90: 490-494.
Quinn, T.P. 2005. The behavior and ecology of Pacific salmon and trout. University of
Washington Press, Seattle, WA, 328 pp.
Schwarz, C.J. and G.A.F. Seber. 1999. Statistical Science. Vol. 14, No. 4, pp. 427-456.
Seber, G.A.F. 1982. The estimation of animal abundance and related parameters. Charles
Griffin and Company, Ltd., London.
Thompson, F.M., S.N. Wick, and B.L. Stratton. 1986. Adult salmon investigations: May–
October, 1985. Technical Data Report No. 13, Alaska Department of Fish and Game,
Susitna Hydro Aquatic Studies, Anchorage, Alaska.
Westerman, D.L. and T.M. Willette. 2013. Upper Cook Inlet salmon escapement studies, 2012.
Alaska Department of Fish and Game, Fishery Data Series No. 13-30, Anchorage,
Alaska.
Yanusz, R.J., R.A. Merizon, T.M. Willette, D.G. Evans, and T.R. Spencer. 2011. Inriver
Abundance and Distribution of Spawning Susitna River Sockeye Salmon Oncorhynchus
nerka, 2008. Alaska Fishery Data Series No. 11-12. Department of Fish and Game,
Divisions of Sport and Fish and Commercial Fisheries.
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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, 2013.
River Section Waterbody
Confluence
Project River
Mile
Miles
Surveyed
Middle River -Indian River Susitna 142.1 14.8 21-Jul 25-Jul 01-Aug 08-Aug 15-Aug
Below Impediment 3 Cheechako Creek Susitna 155.9 2.4 21-Jul 25-Jul 01-Aug 08-Aug 15-Aug
Chinook Creek Susitna 160.4 8.7 19-Jul 25-Jul 01-Aug 08-Aug 15-Aug
Middle River -Devil Creek Susitna 164.8 2.5 19-Jul 25-Jul 01-Aug 08-Aug 15-Aug
Above Impediment 3 Fog Creek Susitna 179.3 19.3 19-Jul 25-Jul 01-Aug 08-Aug 15-Aug
Fog Creek Tributary L1 Fog Mile 5.1 7.6 20-Jul 26-Jul 01-Aug 08-Aug 15-Aug
Unnamed PRM 184.0 Susitna 184.0 5.7 20-Jul 27-Jul 01-Aug 08-Aug 15-Aug
Unnamed PRM 184.0
Tributary R1 Unnamed 0.8 8.2 20-Jul 27-Jul 01-Aug 08-Aug 15-Aug
Tsusena Creek Susitna 184.4 3.6 20-Jul 25-Jul 01-Aug 08-Aug 15-Aug
Upper River -Deadman Creek Susitna 188.4 0.3 20-Jul 27-Jul 01-Aug 09-Aug 15-Aug
Within Reservoir Watana Creek Susitna 196.9 21.3 20-Jul 27-Jul 02-Aug 09-Aug 15-Aug
Watana Creek Tributary
R5 Watana 8.6 8.6 20-Jul 27-Jul 02-Aug 09-Aug No Survey
Kosina Creek Susitna 209.2 18.8 20-Jul 26-Jul 02-Aug 09-Aug 16-Aug
Gilbert Creek Kosina 6.2 6 20-Jul 27-Jul 02-Aug 09-Aug No Survey
Tsisi Creek Kosina 7.3 6.4 20-Jul 27-Jul 02-Aug 09-Aug 16-Aug
Tsisi Lake 1 Tsisi 7.2 2.8 No Survey No Survey No Survey 09-Aug 16-Aug
Tsisi Lake 2 Tsisi 10.6 5.2 No Survey No Survey No Survey 09-Aug 16-Aug
Jay Creek Susitna 211.0 13.3 21-Jul 27-Jul 02-Aug 09-Aug 16-Aug
Upper River -Goose Creek Susitna 232.9 11.2 21-Jul 26-Jul 02-Aug 09-Aug 16-Aug
Above Reservoir Oshetna River Susitna 235.1 26.3 21-Jul 26-Jul 02-Aug 09-Aug 16-Aug
Black River Oshetna 6.2 21-Jul 26-Jul 02-Aug 09-Aug 16-Aug
Survey Dates
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Table 4.4-1. Survey effort and observations using ARIS to identify Chinook salmon spawning behavior in turbid water, 2013.
Site Date Sample Location Latitude Longitude
ARIS
Used
Fish
Observed
Spawning
Observed
Redds
Observed Comments
1 24-Jul 4th of July Creek 62.71482 -149.80826 Yes Yes No No Most fish (90% pinks and some chum) were
just arriving and appeared to be entering
creek.
2 24-Jul 4th of July Slough 62.71574 -149.80327 Yes Yes No No Fish appeared to be holding and waiting
3 25-Jul Indian River Delta Yes Yes Yes No Multiple salmon observed, including Chinook
salmon that were holding in one location for > 1
hr. Likely one Chinook observed had already
spawned as its behavior was indicative of redd
guarding; several fish chased away during
data collection.
4 26-Jul ID'ed by RT'ed CN (724-11)62.65749 -149.95197 Yes No No No Tag in small rapid running along edge of rock
face - not a spawning location.
5 26-Jul ID'ed by RT'ed CN (724-0); near
Gateway
62.67645 -149.89300 No No No -No potential areas for spawning or set-up of
Sonar
6 26-Jul ID'ed by RT'ed CN (876-38); 1/4 mile
d/s Indian on river right
62.78304 -149.66826 Yes Yes No No Single large fish observed on sonar; not
holding and constantly moving
7 26-Jul ID'ed by RT'ed Chinook (876-22),
below Sherman Creek
No No No -Mortality signal upon arrival
8 27-Jul ID'ed by RT'ed Chinook (685-91)No No No -Mortality signal upon arrival
9 27-Jul 4th of July Creek mouth; just u/s 62.81764 -149.80300 No ---Tag not located
10 31-Jul Portage Creek mouth (200-yd stretch
d/s); sites 12 & 13 in 2012
62.83092 -149.38589 Yes Yes No No Lots of fish holding/milling, none could be IDed
as Chinook due to abundance of chum
11 31-Jul Site 11 in 2012 (d/s Portage)No ---Water too swift, did not sample
12 31-Jul Site 10 in 2012 (u/s Indian a ways)No ---Water too swift, did not sample
13 31-Jul Sites 7-9 in 2012 (u/s to d/s Indian)62.78601 -149.65587 Yes Yes No No Fish were migrating, holding, and milling
14 31-Jul Gold Creek area 62.76869 -149.68796 Yes Yes No No Couple of fish observed passing by
15 31-Jul 4th of July Creek Yes Yes No No > 1 hr imagery at the Creek/Slough; lots of PK
trying to get up Creek
16 31-Jul Gateway No No No -No sites suitable for sampling
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Table 4.4-2. Survey effort and observations using ARIS to identify chum salmon spawning behavior in turbid water, 2013.
Site Date Sample Location Latitude Longitude
ARIS
Used
Fish
Observed
Spawning
Observed
Redds
Observed Comments
1 31-Jul 4th of July Creek Yes Yes Yes No
> 1 hr imagery collected at the Creek/Slough; lots of PK
trying to get up the creek
2 31-Jul 4th of July Slough Yes Yes No No Lots of chum in the slough; no spawning, just milling/holding
3 12-Aug 4th of July Slough Yes Yes Yes Yes
Nest guarding behavior and redds visible, but no nest
building behavior
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Table 5.1-2. Number of tagged and untagged adult salmon counted at the Deshka River, Montana Creek,
and Indian River weirs in 2013, by species and size category.
Species1 Tagged
Not
Tagged 2 Total Tagged
Not
Tagged 2 Total Tagged
Not
Tagged Total
Chinook Salmon
METF < 50 cm 0 528 528 0 66 66 13 281 294
METF ≥ 50 cm 148 17,855 18,003 11 1,938 1,949 72 1,065 1,137
Total 148 18,383 18,531 11 2,004 2,015 85 1,346 1,431
Chum Salmon
METF < 40 cm 0 1 1
METF ≥ 40 cm 542 12,305 12,847
Total 542 12,306 12,848
Coho Salmon
METF < 40 cm 0 0 0 0 0 0 0 12 12
METF ≥ 40 cm 67 22,074 22,141 7 758 765 53 461 514
Total 67 22,074 22,141 7 758 765 53 473 526
Pink Salmon
All lengths 2,010 35,171 37,181
Sockeye Salmon
METF < 40 cm 0 6 6
METF ≥ 40 cm 3 117 120
Total 3 123 126
1 Appendix B contains more detailed daily summaries of weir counts for each site.
2 Numbers of fish 'not tagged' were estimated.
Deshka River Weir Montana Creek Weir Indian River Weir 3
3 These data are net upstream counts (or net passage). Subsampled data were expanded accordingly. Only fish released at the Middle
River fishwheels were included in the 'Tagged' field, and only fish of known size category, and fish that were inspected for tags were
included.
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Table 5.2-1. Fate classifications for radio-tagged fish in 2013, by species and release location.
Classification
Lower
River Middle River Yentna Middle River
Lower
River Middle River Middle River
Lower
River Middle River Middle River
Tributary Destinations (total)617 422 602 42 478 154 147 98 151 44
Alexander Creek 2 0 0 0 0 0 0 0 0
Yentna River 72 0 596 0 153 1 0 17 0 0
Deshka River 155 0 0 85 1 0 18 0 1
Willow Creek 37 0 0 6 0 0 16 0 1
Little Willow Creek 22 0 0 5 0 0 2 0 0
Kashwitna Creek 21 0 0 11 0 0 7 0 0
Goose Creek 1 0 0 2 0 0 1 1 0
Sheep Creek 11 1 0 6 0 0 5 0 0
Montana Creek 12 4 1 0 10 1 5 17 4 0
Rabideux Creek 0 0 0 0 2 0 0 0 0 0
Talkeetna River 134 30 4 4 59 20 26 7 21 9
Chulitna River 110 71 1 7 134 65 2 0 0 12
Whiskers Creek 0 0 0 0 10 1 0 0 0
Lane Creek 0 2 0 0 1 8 3 19 0
5th of July Creek 0 0 0 0 0 0 0 5 0
Sherman Creek 0 0 0 0 0 0 0 1 0
4th of July Creek 1 4 0 0 3 1 0 12 1
Gold Creek 0 2 0 0 0 9 1 6 0
Indian River 11 88 18 4 42 59 3 62 11
Jack Long Creek 0 0 0 0 1 0 0 1 0
Portage Creek 26 213 13 1 9 36 1 19 9
Devil Creek 0 1 0 0 0 0 0 0 0
Chinook Creek 0 1 0 0 0 0 0 0 0
Cheechako Creek 2 4 0 0 0 0 0 0 0
Tsusena Creek 0 1 0 0 0 0 0 0 0
Pink SalmonChinook Salmon (≥ 50 cm)
Sockeye
Salmon
Chum
Salmon
Chinook
(< 50 cm)Coho Salmon
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Table 5.2-1. Continued.
Classification
Lower
River Middle River Yentna Middle River
Lower
River Middle River Middle River
Lower
River Middle River Middle River
Mainstem Destinations (total)4 27 0 3 22 19 17 18 15 48
Mainstem Proper 0 7 2 5 7 3 4 2 4
Downstream of Lane 0 2 0 5 3 1 4 0 1
no prior spawn location 0 1 0 5 3 1 2 0 0
was in Kashwitna 0 0 0 0 0 0 1 0 0
was in Talkeetna 0 1 0 0 0 0 1 0 0
was in Portage 0 0 0 0 0 0 0 0 1
Upstream of Lane 0 5 2 0 4 2 0 2 3
no prior spawn location 0 5 2 0 3 2 0 1 2
was in 4th of July 0 0 0 0 0 0 0 1 0
was at Portage Mouth 0 0 0 0 0 0 0 0 1
was in Portage Creek 0 0 0 0 1 0 0 0 0
Tributary Mouths 4 15 0 1 3 1 6 12 2
Yentna Mouth 0 0 0 0 0 0 2 0 0
Deshka Mouth 3 0 0 0 0 0 0 0 0
Willow Mouth 1 0 0 0 0 0 3 0 0
Montana Mouth 0 0 0 1 0 0 0 0 0
Talkeetna Mouth 0 1 0 0 0 0 0 0 0
Lane Mouth 0 1 0 0 1 0 0 2 0
5th of July Mouth 0 0 0 0 1 0 0 1 0
4th of July Mouth 0 1 0 0 0 0 1 3 0
no prior spawn location 0 1 0 0 0 0 1 2 0
was up 4th of July Creek 0 0 0 0 0 0 0 1 0
Indian Mouth 0 6 0 0 0 0 0 4 0
no prior spawn location 0 6 0 0 0 0 0 2 0
was up Indian River 0 0 0 0 0 0 0 2 0
Jack Long Mouth 0 0 0 0 1 0 0 0 0
Portage Mouth 0 6 0 0 0 0 0 2 2
no prior spawn location 0 5 0 0 0 0 0 1 2
was up Portage Creek 0 1 0 0 0 0 0 1 0
Unnamed Creek Mouth 0 0 0 0 0 1 0 0 0
Pink SalmonChinook Salmon (≥ 50 cm)
Sockeye
Salmon
Chum
Salmon
Chinook
(< 50 cm)Coho Salmon
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Table 5.2-1. Continued.
Classification
Lower
River Middle River Yentna Middle River
Lower
River Middle River Middle River
Lower
River Middle River Middle River
Side Channels & Sloughs 0 5 1 16 9 13 8 1 42
Slough 8A 0 0 0 0 0 0 0 0 13
Slough 9 0 0 0 0 0 5 0 0 4
no prior spawn location 0 0 0 0 0 4 0 0 4
was up 4th of July Creek 0 0 0 0 0 1 0 0 0
Slough 11 0 0 0 0 0 0 0 0 6
Slough 21 0 0 0 0 0 0 0 0 0
Other areas 0 5 1 16 9 8 8 1 19
no prior spawn location 0 3 1 16 9 8 8 1 18
was up Portage Creek 0 2 0 0 0 0 0 0 0
was up Talkeetna River 0 0 0 0 0 0 0 0 1
Other Fates (total)68 87 90 22 96 69 37 84 34 45
Other Mainstem 22 43 12 9 63 19 26 37 22 29
Max Zone downstream of Lane 20 0 12 0 61 0 0 35 0 0
Max Zone upstream of Lane 2 43 0 9 2 19 26 2 22 29
Downstream Only 10 30 29 8 12 32 7 0 11 16
Near Release Site 22 14 23 5 11 18 4 10 1 0
No or Single Detections 14 0 26 0 10 0 0 37 0 0
Total Tags Released 689 536 692 67 596 242 201 200 200 137
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)
Sockeye
Salmon
Chum
Salmon
Chinook
(< 50 cm)Coho Salmon
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Table 5.2-2. The proportions of radio-tagged fish of known fate 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, 2013.
Tagged in Lower River
Classification / Fate
Chinook
Salmon
(≥ 50 cm)
Coho
Salmon
Pink
Salmon
Reached Lane Station 58 26 12
Unknown Fate 2 2 2
Known Fate (a)1 56 24 10
Mid/Upper-Susitna Tributary 40 5 8
Mid/Upper-Susitna Mainstem 0 1 1
Returned Downstream (b)1 16 18 1
Mainstem Destination 0 1 0
Chulitna River 14 11 0
Talkeetna River 1 5 1
Sheep Creek 0 1 0
Montana Creek 1 0 0
Proportion Wandering (c)1 28.6%75.0%10.0%
Tagged in Middle River
Classification / Fate
Chinook
Salmon
(≥ 50 cm)
Chinook
Salmon
(< 50 cm)
Chum
Salmon
Coho
Salmon
Pink
Salmon
Sockeye
Salmon
Tagged at Curry 536 67 201 242 200 137
Other Fates (from Table Table 5.2-1)87 22 37 69 34 45
Other Mainstem 43 9 26 19 22 29
Downstream Only 30 8 7 32 11 16
Near Release Site 14 5 4 18 1 0
No / Single Detections 0 0 0 0 0 0
Known Fate (a)1 449 45 164 173 166 92
Mid/Upper-Susitna Tributary 314 31 105 55 106 21
Mid/Upper-Susitna Mainstem 23 3 15 12 12 44
Returned Downstream (b)1 112 11 44 106 48 27
Mainstem Destination 4 0 2 7 3 4
Lane Creek 2 0 8 1 19 0
Whiskers Creek 0 0 1 10 0 0
Chulitna River 71 7 2 65 0 12
Talkeetna River 30 4 26 20 21 9
Montana Creek 4 0 5 1 4 0
Goose Creek 0 0 0 0 1 0
Sheep Creek 1 0 0 0 0 0
Willow Creek 0 0 0 0 0 1
Deshka River 0 0 0 1 0 1
Yentna River 0 0 0 1 0 0
Proportion Wandering (c)1 24.9%24.4%26.8%61.3%28.9%29.3%
Notes:
1 c = a / b
Fish released in the lower river (top panel) were included only if they were detected at or upstream of Lane Station. Fish tagged at Curry
(bottom panel) include all fish released at Curry. See Table 5.2-1 for further details about classifications of fish 'fates.'
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Table 5.2-3. Farthest upstream detection locations for radio-tagged fish that eventually entered a Lower
River tributary, 2013.
Tagged in Lower River
Farthest Upstream Location
Chinook
Salmon
(≥ 50 cm)
Coho
Salmon
Pink
Salmon
Lane Station 3 6 0
Near Curry 2 1 1
Gateway 0 2 0
4th of July Ck. mouth 2 2 0
Slough 11 1 0 0
Gold Creek 0 1 0
Slough 21 1 0 0
Powerline 0 1 0
Jack Long Ck. mouth 1 0 0
Portage Ck. mouth 2 4 0
Above Portage Ck.2 1 0
Below Impediment One 2 0 0
Total number that reached Lane
Station, then entered Lower
River tributary 16 18 1
Tagged at Curry
Farthest Upstream Location
Chinook
Salmon
(≥ 50 cm)
Chinook
Salmon
(< 50 cm)
Chum
Salmon
Coho
Salmon
Pink
Salmon
Sockeye
Salmon
Gateway 8 2 5 5 4 2
4th of July mouth 12 1 5 8 12 2
Indian R. mouth 12 1 0 7 0 1
Gold Creek 0 0 0 1 0 0
Above Indian R.2 0 0 0 0 0
Powerline 8 1 1 24 1 5
Above Powerline 1 0 0 0 0 1
Jack Long Ck. mouth 3 0 0 1 0 0
Portage Ck. mouth 7 0 0 23 0 2
Above Portage Ck.7 1 0 10 0 5
Below Impediment One 7 0 0 3 0 1
Below Impediment Three 1 0 0 0 0 0
Total number that reached
Gateway, then went to a Lower
River spawn location 68 6 11 17 82 19
Notes:
Fish released in the lower river (top panel) were included only if they were detected at or upstream of Lane Station. Fish released
at Curry (bottom panel) were included only if they were detected at or upstream of Gateway.
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Table 5.3-1. Details of the radio-tagged fish that approached or passed the Middle River impediments, 2013.
Chinook Salmon (≥ 50 cm) that Passed Impediment 3
Tag
Number Species 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
241 CN Curry, Site Two 21-Jun 64 Undetermined 13 Jul 14 Jul 16 Jul Approached headwaters, then moved down in
Tsusena Creek (1 day), in Portage Creek (3
days), then down to below Sunshine
272 CN Curry, Site One 23-Jun 64 Undetermined 13 Jul 14 Jul 30 Jul Died in Devils Creek
395 CN Curry, Site One 26-Jun 65 Undetermined 11 Jul 12 Jul 13 Jul Died in Tsesena Creek
Chinook Salmon (≥ 50 cm) that Passed Impediment 2 but not Impediment 3
Tag
Number Species 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
254 CN Curry, Site One 22-Jun 89 Undetermined 12 Jul 13 Jul -Died at mouth of Chinook Creek
280 CN Curry, Site Two 23-Jun 64 Undetermined 13 Jul 13 Jul -Last seen in Talkeetna River
309 CN Curry, Site One 24-Jun 58 Undetermined 12 Jul 13 Jul -Died Below I3
355 CN Curry, Site Two 25-Jun 55 Undetermined 14 Jul 16 Jul -Died in Cheechako Creek
418 CN Curry, Site One 27-Jun 74 Undetermined 13 Jul 13 Jul -In Chinook Creek (7/18-8/7), then quickly
dropped to Chulitna mouth
528 CN Curry, Site One 28-Jun 52 Undetermined 16 Jul 19 Jul -Died in Cheechako Creek
555 CN Curry, Site One 29-Jun 80 Undetermined 24 Jul 24 Jul -Drifted downstream after 7/29, died downstream
658 CN Curry, Site One 30-Jun 67 Undetermined 12 Jul 12 Jul -Drifted downstream after 7/29, was near Slough
21 (8/3-8/2: was inaccessible at the time) then
downstream
715 CN Curry, Site One 1-Jul 60 Undetermined 13 Jul 14 Jul -Died in Cheechako Creek
798 CN Curry, Site One 2-Jul 81 Undetermined 14 Jul 14 Jul -Died in maintem upstream of Chinook Creek
6535 CN Lower Susitna, Site Two 12-Jun 64 Undetermined 12 Jul 13 Jul -In Cheechako Creek (7/16 - 7/31), then
downstream
6604 CN Lower Susitna, Site Two 8-Jun 60 Undetermined 17 Jul 18 Jul -In Cheechako Creek (7/23-7/31, as late an 8/4),
then downstream
7082 CN Lower Susitna, Site Two 15-Jun 55 Undetermined 13 Jul 14 Jul -In Portage Creek (7/27-8/7) then various
downstream locations
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Table 5.3-1. Continued.
Chinook Salmon (≥ 50 cm) that Passed Impediment 1 but not Impediment 2
Tag
Number Species 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
219 CN Curry, Site One 21-Jun 93 Undetermined 30 Jun --In Portage Creek (7/7-8/8) then Jack Long
Creek (8/10), then various mainstem locations
278 CN Curry, Site One 23-Jun 63.5 Undetermined 13 Jul --Died at Portage Mouth
353 CN Curry, Site Two 25-Jun 68 Undetermined 14 Jul --Died in Portage Creek
593 CN Curry, Site One 29-Jun 88 Male 16 Jul --Died in Cheechako Creek
Chinook Salmon (≥ 50 cm) that Approached Impediment 1 but did not Pass
Tag
Number Species 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
176 CN Curry, Site Two 17-Jun 60 Undetermined ---Last in Talkeetna River
178 CN Curry, Site Two 17-Jun 62 Undetermined ---Died in Portage Creek
210 CN Curry, Site One 20-Jun 82 Undetermined ---Died in Portage Creek
224 CN Curry, Site One 21-Jun 58 Undetermined ---Last in Chulitna River
299 CN Curry, Site One 24-Jun 52 Undetermined ---In Portage Creek 7/20 - 8/10
328 CN Curry, Site One 25-Jun 81 Female ---
In Portage Creek 7/10 - 7/13, then in a side-
Channel near Slough 21
332 CN Curry, Site One 25-Jun 82 Undetermined ---Died in Portage Creek
338 CN Curry, Site One 25-Jun 78 Male ---In Portage Creek 7/20 - 7/30
347 CN Curry, Site One 25-Jun 81 Female ---Died in Portage Creek
404 CN Curry, Site One 26-Jun 55 Undetermined ---Died in Portage Creek
447 CN Curry, Site One 27-Jun 53 Undetermined ---Died in Portage Creek
479 CN Curry, Site Two 27-Jun 80 Undetermined ---Died in Portage Creek
501 CN Curry, Site One 28-Jun 84 Undetermined ---Died in Below I1
517 CN Curry, Site One 28-Jun 85 Undetermined ---Died in Gold Creek
524 CN Curry, Site One 28-Jun 66 Undetermined ---Died in Portage Creek
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Table 5.3-1. Continued.
Chinook Salmon (≥ 50 cm) that Approached Impediment 1 but did not Pass
Tag
Number Species 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
532 CN Curry, Site One 28-Jun 80 Undetermined ---In Portage Creek 7/17 - 7/24
541 CN Curry, Site One 29-Jun 64 Undetermined ---Died in Portage Creek
543 CN Curry, Site One 29-Jun 54 Undetermined ---Died in Portage Creek
550 CN Curry, Site One 29-Jun 61 Undetermined ---Last in Chulitna River
564 CN Curry, Site One 29-Jun 86 Male ---
In Portage Creek (7/15-7/27), then various
downstream locations
615 CN Curry, Site One 30-Jun 61 Undetermined ---In Portage Creek 7/7 - 8/11
632 CN Curry, Site One 30-Jun 71 Male ---Died in Portage Creek
671 CN Curry, Site One 30-Jun 80 Female ---Last in Chulitna River
700 CN Curry, Site One 1-Jul 56 Undetermined ---Died in Portage Creek
714 CN Curry, Site One 1-Jul 56 Undetermined ---Last in Chulitna River
746 CN Curry, Site One 1-Jul 63 Undetermined ---
In Portage Creek (7/15-7/19) then died at
Portage mouth
760 CN Curry, Site Two 1-Jul 62 Undetermined ---In Portage Creek (7/18) then downstream
762 CN Curry, Site One 2-Jul 75 Undetermined ---Died near Portage Mouth
764 CN Curry, Site One 2-Jul 72 Undetermined ---Last in Chulitna River
781 CN Curry, Site One 2-Jul 63 Undetermined ---
In Portage Creek (7/22 - 7/31, maybe as long as
8/6), then downstream
815 CN Curry, Site One 2-Jul 86 Undetermined ---Died in Portage Creek
880 CN Curry, Site One 3-Jul 59 Undetermined ---
o tage C ee (8/ 6), ded ea o tage
mouth
920 CN Curry, Site One 4-Jul 67 Undetermined ---Died in Indian River
925 CN Curry, Site Two 4-Jul 83 Male ---Died downstream of I1
927 CN Curry, Site Two 4-Jul 82 Undetermined ---Died in Portage Creek
951 CN Curry, Site One 5-Jul 78 Female ---Died in Portage Creek
962 CN Curry, Site Two 5-Jul 67 Undetermined ---Died in Portage Creek
1004 CN Curry, Site One 8-Jul 91 Undetermined ---Died Below I1
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Table 5.3-1. Continued.
Chinook Salmon (≥ 50 cm) that Approached Impediment 1 but did not Pass
Tag
Number Species 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
1039 CN Curry, Site Two 9-Jul 63 Undetermined ---Died in Portage Creek
1056 CN Curry, Site One 10-Jul 54 Undetermined ---Died in Portage Creek
1061 CN Curry, Site One 10-Jul 84 Male ---In Portage Creek 7/15, then in Talkeetna River
1081 CN Curry, Site One 11-Jul 58 Undetermined ---Died in Portage Creek
1149 CN Curry, Site One 16-Jul 81 Female ---Died in Portage Creek
6811 CN Lower Susitna, Site Two 9-Jun 59 Undetermined ---In Chulitna River
6866 CN Lower Susitna, Site One 10-Jun 85 Undetermined ---Died in Portage Creek
6885 CN Lower Susitna Gillnets 15-Jun 72 Undetermined ---
In Portage Creek (7/7-7/9, 7/13-7/27), then
downstream
7063 CN Lower Susitna, Site One 10-Jun 84 Undetermined ---Died in Portage Creek
7203 CN Lower Susitna Gillnets 7-Jun 54 Undetermined ---In Chulitna River
7255 CN Lower Susitna, Site One 10-Jun 77 Undetermined ---Died in Portage Creek
7281 CN Lower Susitna, Site One 14-Jun 67.5 Undetermined ---In 4th of July Creek
Chinook Salmon(< 50 cm) that Passed Impediment 1 but not Impediment 2
Tag
Number Species Capture/ Release Site
Capture
Date
Length
(MEF
cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
1024 CNj Curry, Site Two 8-Jul 42 Male 26 Jul --In lower Portage Creek, then died in Indian
River
Chinook Salmon (< 50 cm) that Approached Impediment 1 but did not Pass
Tag
Number Species Capture/ Release Site
Capture
Date
Length
(MEF
cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
713 CNj Curry, Site One 1-Jul 40 Undetermined ---Died in Portage Creek
717 CNj Curry, Site One 1-Jul 35 Undetermined ---Drifted Downstream
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Table 5.3-1. Continued.
Chinook Salmon (< 50 cm) that Approached Impediment 1 but did not Pass
Tag
Number Species Capture/ Release Site
Capture
Date
Length
(MEF
cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
959 CNj Curry, Site Two 5-Jul 35 Undetermined ---Died in Portage Creek
1117 CNj Curry, Site Two 13-Jul 39 Male ---In lower Portage Creek, then died in Indian
Sockeye Salmon that Approached Impediment 1 but did not Pass
Tag
Number Species Capture/ Release Site
Capture
Date
Length
(MEF
cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
898 SO Curry, Site One 4-Jul 51 Undetermined ---Below I1, then mortality signals detected at the
mouth of Portage Creek
1074 SO Curry, Site One 11-Jul 58 Female ---Portage mouth (7/15-7/28) then downstream,
and up again to a Slough below Gold Creek
(7/31-8/12)
1093 SO Curry, Site One 12-Jul 57 Undetermined ---In Portage Creek (7/18-7/20) then in a mainstem
area near Birch Creek (7/25 then mort)
2011 SO Curry, Site Two 26-Jul 46 Undetermined ---Drifted Downstream
2216 SO Curry, Site Three 28-Jul 50 Undetermined ---Died in Indian River
2414 SO Curry, Site One 31-Jul 59 Undetermined ---Drifted Downstream
2724 SO Curry, Site Three 2-Aug 50 Male ---Died in Slough 11
2900 SO Curry, Site One 4-Aug 56 Male ---At mouth of Portage
3831 SO Curry, Site Two 10-Aug 56 Male ---Died in Indian River
Coho Salmon that Approached Impediment 1 but did not Pass
Tag
Number Species Capture/ Release Site
Capture
Date
Length
(MEF
cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
2522 CO Curry, Site One 1-Aug 54 Undetermined ---Below I1 (8/10) then Chulitna
2705 CO Curry, Site Three 2-Aug 45 Undetermined ---Above Portage, Portage mouth, Below I1 (~8/22-
26) then Chulitna
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Table 5.3-1. Continued.
Coho Salmon that Approached Impediment 1 but did not Pass
Tag
Number Species Capture/ Release Site
Capture
Date
Length
(MEF
cm)Sex
First
Detection
Above I-1
First
Detection
Above I-2
First
Detection
Above I-3 Comments
2805 CO Curry, Site Two 3-Aug 53 Undetermined ---Portage area, Below I1 (8/27 - ~29) then
Whiskers Creek
3304 CO Curry, Site Three 6-Aug 55 Female ---Below I1 (8/11) then Chulitna
3511 CO Curry, Site Three 7-Aug 43 Male ---Below I1 (8/27 - ~29) then Chulitna
3626 CO Curry, Site Two 8-Aug 51 Male ---Portage mouth, then Below I1 (~8/29 8/30, ~9/1 -
9/2) then Mainstem in Zone 125 (2 live hits then
mort)
Notes:
Fish characteristics include 'tag numbers' (unique numbers assigned to each individual radio-tagged fish), species (CN = Chinook salmon ≥ 50 cm; CNj = Chinook salmon < 50 cm; and SO =
sockeye salmon), 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 passed Impediment 1 but not Impediment 2. Sixth panel: Chinook salmon (< 50 cm) that approached within 1 km of Impediment 1, but did not pass. Seventh
panel: sockeye salmon that approached within 1 km of Impediment 1, but did not pass.
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Table 5.3-2. Destinations of radio-tagged Chinook salmon that passed each Middle River impediment, 2013.
Chinook
(< 50 cm)
Passed I1
but not I2
Passed I2
but not I3 Passed I3 Total
Passed I1
but not I2
Classification
Tributary Destinations
Talkeetna River 1 1
Indian River 1
Portage Creek 2 1 1 4
Cheechako Creek 1 5 6
Chinook Creek 1 1
Devils Creek 1 1
Tsesena Creek 1 1
Mainstem Destinations
Near Slough 11 1
Near Slough 21 1
Near Portage 1 1
Near Chinook 1 1
Mort 2 2
Total 4 13 3 20 1
Downstream from Impediment
Number 3 9 1 13 1
Percent 75%69%33%65%100%
Notes:
An “I” refers to “impediment.”
Chinook Salmon (≥ 50 cm)
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Table 5.5-1. Average percent distribution of spawning salmon in slough habitats of the Middle River from
1981 to 1985, and confirmed spawning locations in 2012 and 2013.
Slough River Mile Sockeye Chum Pink 2012 2013 2012 2013 2012 2013
1 99.6 0.3 0.1 -
2 100.2 0.2 1.5 0.1
3B 101.4 0.8 0.2 0.7
3A 101.9 0.4 0.1 2.2
4 105.2 ---
5 107.6 0.0 0.0 0.1
6 108.2 ---
6A 112.3 0.0 0.2 2.8
7 113.2 ---
8 113.7 0.1 3.3 20.7
Bushrod 117.8 0.1 1.2 4.0
8D 121.8 -0.5 -
8C 121.9 0.1 1.5 0.0
8B 122.2 0.2 6.3 4.1
Moose 123.5 1.6 2.9 1.0
A'124.6 -2.5 0.6
A 124.7 -0.5 3.0
8A 125.4 13.8 13.7 8.1 X X X X
B 126.3 0.8 2.3 2.1
9 128.3 0.6 8.9 1.9 X X X X X
9B 129.2 1.9 1.2 -
9A 133.8 0.1 6.0 -X X X
10 133.8 0.1 0.2 -X X
11 135.3 65.6 20.9 17.6 X X X X
12 135.4 ---
13 135.9 -0.2 -
14 135.9 -0.0 -
15 137.2 0.0 0.7 19.4
16 137.3 -0.2 35.7
17 138.9 0.8 2.4 0.0
18 139.1 -0.1 -
19 139.7 0.8 0.2 1.3 X
20 140.0 0.0 2.5 13.6
Percent Distribution Confirmed Spawning
(1981-1985 average)Sockeye Chum Pink
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Table 5.5-1. Continued.
Slough River Mile Sockeye Chum Pink 2012 2013 2012 2013 2012 2013
21 141.1 13.2 22.1 4.5 X X X X
22 144.5 0.1 3.7 -X
21A 145.3 -0.1 -X
Total Fish Count (1981-85)4,252 15,827 1,639
Notes:
Average percent distribution data were synthesized from Barrett et al. (1985) and Thompson et al. (1986).
Annual total counts for each species:
1981: sockeye (1,241), chum (2,596), and pink salmon (28)
1982: sockeye (607), chum (2,244), and pink salmon (507)
1983: sockeye (555), chum (1,467), and pink salmon (21)
1984: sockeye (926), chum (7,556), and pink salmon (1,069)
1985: sockeye (923), chum (1,964), and pink salmon (14)
Percent Distribution Confirmed Spawning
(1981-1985 average)Sockeye Chum Pink
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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, 2013.
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Figure 4.1-1. Middle River Segment showing sites for fish capture (sites 1, 2, and 3), ARIS, rotary screw trap
(RST), Curry camp, and the Lane Creek and Gateway fixed-station receivers, 2013.
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Figure 4.3-1. Aerial spawner survey extent for Indian River and tributaries in and above Devils Canyon, 2013.
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Figure 5.2-1. Fate classifications for radio-tagged fish released in the lower river (left panels) or at Curry
(right panels), by species/life history stage, 2013. Top panels: 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, and those that had at least one live detection in
the mainstem location. See text and Table 5.2-1 for more detailed classifications. Middle Panels: Relative use
of side-channel/slough locations, tributary mouths, and the mainstem proper, by fish that were classified with
a 'Mainstem Destination.' Bottom Panel: Relative use of sloughs vs. side-channel habitats by fish classified
with a 'Mainstem Destination.' 'tbd' = to be determined.
0%
20%
40%
60%
80%
100%
Chinook
Salmon
Pink
Salmon
Coho
SalmonRelative FrequencyTributary Mainstem Other
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
Salmon
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
Chinook
(small)
General Classification
Releases from Curry
0%
20%
40%
60%
80%
100%
Chinook
Salmon
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
Chinook
(small)
Mainstem Use
Releases from Curry
0%
20%
40%
60%
80%
100%
Chinook
Salmon
Pink
Salmon
Coho
Salmon
Sockeye
Salmon
Chum
Salmon
Chinook
(small)Relative FrequencySlough 8A
Slough 9
Slough 11
Slough 21
Side-channels
Side -channel / Slough Use
Releases from Curry
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Figure 5.3-1. Daily numbers of Chinook salmon that approached and passed each of the three Middle River
impediments in 2013. 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 as measured at Tsusena
Creek.
0
2
4
6
8
10
12
14
16
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
6/30 7/3 7/6 7/9 7/12 7/15 7/18 7/21 7/24 7/27 7/30 8/2 8/5 8/8 8/11 8/14Number of Fish at I1Tsusena Discharge (cfs)Date (m/d)
Chinook Salmon
Impediment 1
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
6/30 7/3 7/6 7/9 7/12 7/15 7/18 7/21 7/24 7/27 7/30 8/2 8/5 8/8 8/11 8/14Number of Fish at I3Tsusena Discharge (cfs)Approached (did not pass)
Passed
Chinook Salmon
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
6/30 7/3 7/6 7/9 7/12 7/15 7/18 7/21 7/24 7/27 7/30 8/2 8/5 8/8 8/11 8/14Number of Fish at I2Tsusena Discharge (cfs)Chinook Salmon
Impediment 2
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Figure 5.3-2. Daily number of radio-tagged Chinook salmon that held below Impediment 3 in 2013. Each of
the three 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. The top panel includes the average daily flow of the Susitna River as
measured at Tsusena Creek, and the bottom panel includes the average daily water temperature of the
Susitna River as measured at Tsusena Creek.
0
5,000
10,000
15,000
20,000
25,000
30,000
0
1
2
3
6/30 7/2 7/4 7/6 7/8 7/10 7/12 7/14 7/16 7/18 7/20 7/22 7/24 7/26 7/28 7/30 8/1 8/3 8/5 8/7 8/9 8/11 8/13 8/15Tsusena Discharge (cfs)Radio-tagged Chinook SalmonTag 272
Tag 241
Tag 395
Flow
Chinook Salmon that Passed Impediment 3
6
7
8
9
10
11
12
13
14
15
0
1
2
3
6/30 7/2 7/4 7/6 7/8 7/10 7/12 7/14 7/16 7/18 7/20 7/22 7/24 7/26 7/28 7/30 8/1 8/3 8/5 8/7 8/9 8/11 8/13 8/15Tsusena Temperature (°C)Radio-tagged Chinook SalmonDate (m/d)
Tag 272
Tag 241
Tag 395
Flow
Chinook Salmon that Passed Impediment 3
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PART A - APPENDIX A: FISH CAPTURE AND TAGGING
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Table A-1. Number of salmon radio-tagged at two fishwheel sites and from gillnets in the Lower River, 2013.
Table A-2. Number of Chinook salmon radio-tagged at two fishwheel sites and in gillnets in the Yentna
River, 2013.
Radio Tag
Species Target West Bank East Bank Gillnet Total
Chinook salmon1 700 385 195 118 698
Coho Salmon 600 343 253 596
Pink Salmon 200 99 98 197
Total 1,500 827 546 118 1,491
1 Adult fish measuring 50 cm METF or greater.
Fishwheel
South Bank North Bank Gillnet Total
700 282 143 267 692
Notes:
All tagged Chinook salmon measured 50 cm METF or greater.
FishwheelRadio Tag
Target
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Table A-3. Number of salmon radio- and spaghetti-tagged at three fishwheel sites and in a beach seine in the Middle River, 2013.
Species Radio Spaghetti Radio Spaghetti Radio Spaghetti Radio Radio Spaghetti Total
Chinook salmon (≥ 50 cm)560 449 81 6 536 536
Chinook salmon (< 50 cm)0 55 12 67 67
Chum Salmon 200 16 252 78 344 107 1,363 201 1,959 2,160
Coho Salmon 200 75 484 54 98 102 380 11 242 962 1,204
Pink Salmon 200 32 346 81 1,239 87 7,520 200 9,105 9,305
Sockeye Salmon 200 58 51 30 139 139
Total 1,360 685 1,082 357 1,681 332 9,263 11 1,385 12,026 13,411
Total
Fishwheels Beach
SeineRadio
Tag
Target
Site 1 Site 2 Site 3
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Table A-4. Number of fish sampled at the Middle River fishwheels (length, fin clip, and scales) and
transferred to the FDA Study to be surgically radio-tagged, 2013.
Table A-5. Number of salmon captured at two fishwheel sites and in gillnets in the Lower River, 2013.
Total
Species Name Catch1 Min Max Mean n Tagged n DNA Scales
Chinook Salmon (≥ 50 cm)616 50 110 69.6 576 542 283
Chinook Salmon (< 50 cm)336 23 49 36.3 320 67 33
Chum Salmon 3,417 27 70 59.0 1,358 201
Coho Salmon 1,734 31 67 51.1 1,030 220 120
Pink Salmon 15,695 31 61 41.6 1,696 199
Sockeye Salmon 276 24 64 44.8 261 138 86
Arctic Grayling 54 20 40 33.8 51 10 11 40
Burbot 2 41 45 42.8 2 1 2 1
Dolly Varden 14 19 43 28.6 14 2 3 11
Longnose Sucker 20 20 39 29.4 20 5 8 5
Rainbow Trout 59 15 46 32.1 52 8 11 33
Round Whitefish 104 14 42 27.2 102 12 18 56
Humpback Whitefish 20 24 38 28.7 17 2 6 10
1 Total catch for chum, coho, pink, and sockeye salmon includes all adult fish, regardless of length.
2
Mid-eye-to-fork Length
Nose-fork Length
Some fish captured at the Middle River fishwheels were transferred to Fish Distribution & Abundance (FDA) crews to be surgically radio-
tagged at Curry; and a portion of these fish were released untagged.
Length (cm)Transferred to FDA2 Biosamples
Species West Bank East Bank Gillnet
Chinook Salmon 1,120 789 154 2,063
Chum Salmon 1,337 2,175 3,512
Coho Salmon 2,164 1,113 3,277
Pink Salmon 16,177 17,818 33,995
Sockeye Salmon 364 260 624
Total 21,162 22,155 154 43,471
Notes:
Totals include all adult salmon regardless of size, as well as all recaptured fish.
Fishwheels All Gear
Combined
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Table A-6. Number of Chinook salmon captured at two fishwheel sites and in gillnets in the Yentna River,
2013.
Table A-7. Number of salmon caught in the Lower River and Yentna River and their length statistics, 2013.
South North Gillnet
1,050 951 295 2,296
Notes:
Totals include all adult salmon regardless of size, as well as all recaptured fish.
All Gear
Combined
Fishwheels
Location Total
Species Name Catch Min Max Mean n
Lower River
Chinook Salmon (≥ 50 cm)1,232 50.0 106.0 65.7 1,232
Chinook Salmon (< 50 cm)831 24.5 49.5 36.6 831
Chum Salmon 3,512 ----
Coho Salmon 3,277 24.5 62.0 49.7 3,290
Pink Salmon 33,995 40.0 50.5 42.8 200
Sockeye Salmon 624 ----
Yentna River
Chinook Salmon (≥ 50 cm)1,201 50.0 107.0 65.8 1,094
Chinook Salmon (< 50 cm)1,094 20.5 49.5 35.2 1,200
Length (cm METF)
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Table A-8. Number of salmon captured at three fishwheel sites and in a beach seine in the Middle River, by size category, 2013.
Species Large Small Total Large Small Total Large Small Total Large Large Small Total
Chinook Salmon 514 262 776 89 64 153 13 10 23 616 336 952
Chum Salmon 1,263 1,263 510 510 1,644 1,644 3,417 3,417
Coho Salmon 949 1 950 186 5 191 576 6 582 11 1,722 12 1,734
Pink Salmon 2,385 2,385 2,125 2,125 11,185 11,185 15,695 15,695
Sockeye Salmon 73 18 91 64 50 114 39 32 71 176 100 276
Total 5,184 281 5,465 2,974 119 3,093 13,457 48 13,505 11 21,626 448 22,074
Notes:
Totals include all tagged fish recaptured at the fishwheels. Large Chinook salmon measured 50 cm METF or greater; and large chum, coho, pink, and sockeye salmon measured 40 cm
METF or greater.
Fishwheels Beach
Seine All Gear CombinedSite 1 Site 2 Site 3
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Figure A-1. Daily fishing effort (hours) and rotational speed (RPM) at two fishwheel sites in the Lower River,
2013.
Figure A-2. Daily gillnet effort (hours) in the Lower River, by mesh size, 2013.
Date (m/d)Rotational Speed (RPM)Fishing Effort (h)0
1
2
3
4
5
0
2
4
6
8
10
12
14
6/36/76/116/156/196/236/277/17/57/97/137/177/217/257/298/28/68/108/148/188/228/268/30Effort
RPM
West Bank
0
1
2
3
4
5
0
2
4
6
8
10
12
14
6/36/76/116/156/196/236/277/17/57/97/137/177/217/257/298/28/68/108/148/188/228/268/30East Bank
0
1
2
3
4
6/36/56/76/96/116/136/156/176/196/216/236/256/276/297/1Fishing 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 two fishwheel sites in the Yentna River, 2013.
Figure A-4. Daily gillnet effort (hours) in the Yentna River, by mesh size, 2013. Fishing Effort (h)Date (m/d)
0
2
4
6
8
6/26/46/66/86/106/126/146/166/186/206/226/246/266/286/30South Bank
0
2
4
6
8
6/26/46/66/86/106/126/146/166/186/206/226/246/266/286/30North Bank
0
2
4
6
8
6/36/56/76/96/116/136/156/176/196/21Fishing Effort (h)Date (m/d)
7.5-in Mesh
5.5-in Mesh
Gillnet
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Figure A-5. Daily fishing effort (hours) and rotational speed (RPM) at three fishwheel sites in the Middle
River, 2013.
Date (m/d)Rotational Speed (RPM)Fishing Effort (h)0
2
4
6
8
0
4
8
12
16
20
24
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Effort
RPM
Site 1 (west bank)
0
2
4
6
8
0
4
8
12
16
20
24
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Site 2 (east bank)
0
2
4
6
8
0
4
8
12
16
20
24
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Site 3 (west bank)
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Figure A-6. Daily number of radio tags applied to adult Chinook, pink, and coho salmon captured at two
fishwheel sites and in gillnets in the Lower River, 2013.
Figure A-7. Daily number of radio tags applied to adult Chinook salmon captured at two fishwheel sites and
in gillnets in the Yentna River, 2013.
Date (m/d)Radio Tags Applied0
50
100
150
6/36/106/176/247/17/87/157/227/298/58/128/19Gillnet
East Bank
West Bank
Chinook
0
5
10
15
20
6/36/106/176/247/17/87/157/227/298/58/128/19Pink
0
10
20
30
40
6/36/106/176/247/17/87/157/227/298/58/128/19Coho
0
20
40
60
80
100
6/36/56/76/96/116/136/156/176/196/216/236/256/276/29Radio Tags AppliedDate (m/d)
Gillnet
North Bank
South Bank
Chinook
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Figure A-8. Daily number of radio tags applied to adult Chinook, sockeye, pink, chum, and coho salmon
captured at three fishwheel sites in the Middle River, 2013.
Date (m/d)Radio Tags Applied0
15
30
45
60
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Site 3 (west bank)
Site 2 (east bank)
Site 1 (west bank)
Chinook
(≥ 50 cm)
0
2
4
6
8
10
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Chinook
(< 50 cm)
0
2
4
6
8
10
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Sockeye
0
5
10
15
20
25
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Pink
0
5
10
15
20
25
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Chum
051015202530
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Coho
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Figure A-9. Daily sampling effort, and the amount of imagery reviewed (review effort), for two ARIS units
operated immediately downstream of the fishwheel at Site 1 in the Middle River, 2013.
Date (m/d)Sampling Effort (hours)Review Effort (hours)0
4
8
12
16
20
24
0
4
8
12
16
20
24
6/76/146/216/287/57/127/197/268/28/98/168/238/309/69/139/209/27Unit 1
0
4
8
12
16
20
24
0
4
8
12
16
20
24
6/76/146/216/287/57/127/197/268/28/98/168/238/309/69/139/209/27Sampling Effort (h)
Review Effort (h)
Unit 2
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Figure A-10. Daily catch-per-unit-effort at the Lower River fishwheels, by species, and the Susitna River
discharge at Sunshine, 2013.
Figure A-11. Daily catch-per-unit-effort for Chinook salmon at the Yentna River fishwheels, and the Yentna
River discharge at Lake Creek, 2013. Catch-per-unit-effort (fish per hour)Discharge (cfs)Date (m/d)
0
30,000
60,000
90,000
120,000
150,000
0
2
4
6
8
10
12
6/16/86/156/226/297/67/137/207/278/38/108/178/248/31Discharge
East Bank
West Bank
Chinook
0
30,000
60,000
90,000
120,000
150,000
0
50
100
150
200
250
6/16/86/156/226/297/67/137/207/278/38/108/178/248/31Pink
0
30,000
60,000
90,000
120,000
150,000
0
2
4
6
8
10
6/16/86/156/226/297/67/137/207/278/38/108/178/248/31Coho
0
15,000
30,000
45,000
60,000
75,000
90,000
-
2
4
6
8
10
12
6/26/46/66/86/106/126/146/166/186/206/226/246/266/286/30Discharge (cfs)Catch-per-unit-effort (fish per hour)Date (m/d)
Discharge
North Bank
South Bank
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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, 2013.
Date (m/d)Discharge (cfs)Catch-per-unit-effort (fish per hour)0
15,000
30,000
45,000
60,000
75,000
90,000
0.0
0.4
0.8
1.2
1.6
2.0
2.4
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Discharge
Site 1
Site 2
Site 3
Chinook
0
15,000
30,000
45,000
60,000
75,000
90,000
0.0
0.2
0.4
0.6
0.8
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Sockeye
0
15,000
30,000
45,000
60,000
75,000
90,000
0
20
40
60
80
100
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Pink
0
15,000
30,000
45,000
60,000
75,000
90,000
0
2
4
6
8
10
12
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Chum
0
15,000
30,000
45,000
60,000
75,000
90,000
0
2
4
6
8
10
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Coho
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Figure A-13. Daily number of radio tags deployed at the Middle River fishwheels relative to fishwheel
catches in the 1980s, 2012, and 2013.
Date (m/d)Relative Proportion of Curry Fishwheel Catch and Radio Tags Deployed0.00
0.03
0.06
0.09
0.12
6/16/86/156/226/297/67/137/207/278/38/108/178/248/319/79/149/212013 Tags
2013 Catch
2012 Catch
1981-85 Catch
Chinook
(target =560 tags)
0.00
0.02
0.04
0.06
0.08
6/16/86/156/226/297/67/137/207/278/38/108/178/248/319/79/149/21Sockeye
(target = 200 tags)
0.00
0.03
0.06
0.09
0.12
0.15
6/16/86/156/226/297/67/137/207/278/38/108/178/248/319/79/149/212013 Tags
2013 Catch
2012 Catch
81/83/85
Pink
(target = 200 tags)
0.00
0.03
0.06
0.09
0.12
6/16/86/156/226/297/67/137/207/278/38/108/178/248/319/79/149/21Chum
(target = 200 tags)
0.00
0.03
0.06
0.09
0.12
6/16/86/156/226/297/67/137/207/278/38/108/178/248/319/79/149/21Coho
(target = 200 tags)
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Figure A-14. Daily number of spaghetti tags applied to adult pink, chum, and coho salmon captured at three
fishwheel sites in the Middle River, 2013.
Spaghetti Tags AppliedDate (m/d)
0
250
500
750
1,000
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Site 3 (west bank)
Site 2 (east bank)
Site 1 (west bank)
Pink
0
50
100
150
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Chum
0
50
100
150
6/96/166/236/307/77/147/217/288/48/118/188/259/19/89/159/229/29Coho
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Figure A-15. Cumulative length-frequency distributions for salmon radio-tagged in the Middle River and
inspected and recaptured at the Indian River weir site, by species, 2013. Cumulative ProportionMid-eye to Fork Length (cm)
0.0
0.2
0.4
0.6
0.8
1.0
40 50 60 70 80 90 100 110 120
Chinook
(≥ 50 cm)
Radio-tagged in
Middle River
Inspected at Weir
Recaptured at Weir
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70 75 80
Sockeye
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70 75 80
Pink
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70 75 80
Chum
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70 75 80
Coho
0.0
0.2
0.4
0.6
0.8
1.0
20 25 30 35 40 45 50 55
Chinook
(< 50 cm)
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Figure A-16. Cumulative length-frequency distributions for salmon spaghetti-tagged in the Middle River and
inspected and recaptured at the Indian River weir site, by species, 2013.
Cumulative ProportionMid-eye to Fork Length (cm)
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70
Pink
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70 75 80
Chum
Spaghetti-
tagged in
Middle River
Inspected at
Weir
Recaptured at
Weir
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70 75 80
Coho
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Figure A-17. Catch-per-unit-effort, or the number of targets counted per hour of imagery reviewed, on the
ARIS (Unit 1) located immediately downstream of the Site 1 fishwheel, 2013. All ARIS data were included,
regardless of whether the Site 1 fishwheel was operational. From June 7 to July 12, only targets measuring
50 cm or greater were recorded from ARIS imagery, whereas from August 30 to September 17, targets
measuring 40 cm or greater were recorded. Turbidity measurements at Site 1 are also shown.
Figure A-18. Comparison of the number of adult salmon (≥ 50 cm METF) captured at the Site 1 fishwheel
and concurrent net upstream counts of fish on the ARIS unit (Unit 1) located immediately downstream of the
fishwheel, 2013. From June 7 to July 12, only targets measuring 50 cm or greater were recorded from ARIS
imagery, whereas from August 30 to September 17, targets measuring 40 cm or greater were recorded.
Discharge of the Susitna River at Gold Creek is also shown.
0
40
80
120
160
200
0
3
6
9
12
15
18
6/76/146/216/287/57/127/197/268/28/98/168/238/309/69/139/209/27Turbidity (NTU)Catch-per-unit-effort(fish/hour)Date (m/d)
CPUE
Turbidity
0
10,000
20,000
30,000
40,000
50,000
0
30
60
90
120
150
6/76/146/216/287/57/127/197/268/28/98/168/238/309/69/13Discharge (cfs)Net Upstream ARIS Countsand Fishwheel CatchDate (m/d)
Discharge
ARIS Count
Fishwheel Catch
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Figure A-19. Number of fish counted using ARIS at Site 1 as a function of the distance from each unit where
they were first detected in the field of view, by time period and size category, 2013.
Relative Proportion (%)0
8
16
24
32
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
June 16 -July 12 (≥ 50 cm)
September 1-30 (≥ 40 cm)
Unit 1
0
8
16
24
32
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
Distance from ARIS Unit 1 (m)
September 1-30 (≥ 40 cm)
Unit 2
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Figure A-20. Diel migration of fish counted using ARIS (Unit 1) at Site 1, by size category, 2013. Only
upstream-moving fish counted during periods when 24-hours of imagery was reviewed were included. The
top panel shows counts from June 16 to July 12 when mainly Chinook salmon were being captured at the Site
1 fishwheel. The bottom panel shows counts from September 1–30 when chum and coho salmon were
presumably the predominant species migrating through the Middle River.
ARIS CountsTime of Day
0
20
40
60
80
01234567891011121314151617181920212223METF ≥ 50 cm (n = 1050)June 16 -July 12
0
20
40
60
80
100
120
01234567891011121314151617181920212223METF ≥ 50 cm (n = 1184)
METF = 40-49 cm (n = 476)
September 1-30
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FERC Project No. 14241 Part A - Appendix A – Page 21 June 2014
Figure A-21. Cumulative length-frequency distributions for salmon captured in the Lower River, by species
and capture site, 2013.
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
Chinook
West Bank
East Bank
Gillnet
0.0
0.2
0.4
0.6
0.8
1.0
35 40 45 50 55 60
Pink
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70
Coho
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Figure A-22. Cumulative length-frequency distributions for salmon caught and radio-tagged in the Lower
River, by species, 2013.
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
Chinook
West Bank
East Bank
Gillnet
0.0
0.2
0.4
0.6
0.8
1.0
35 40 45 50 55 60
Pink
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70
Coho
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Figure A-23. Cumulative length-frequency distributions for salmon radio-tagged in the Lower River and
inspected and recaptured at the Deshka River and Montana Creek weir sites, by species, 2013.
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 90 100 110 120 130
Montana Weir
Chinook
Tagged in Lower River
Inspected at Weir
Recaptures at Weir
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70 75 80
Montana Weir
Coho
0.0
0.2
0.4
0.6
0.8
1.0
30 40 50 60 70 80 90 100 110 120 130
Deshka Weir
Chinook
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70 75 80
Deshka Weir
Coho
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Figure A-24. Cumulative length-frequency distribution for Chinook salmon captured in the Yentna River, by
capture site, 2013.
Figure A-25. Cumulative length-frequency distribution for Chinook salmon caught and radio-tagged in the
Yentna River, 2013.
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 90 100 110 120 130
Chinook
South Bank
North Bank
Gillnet
Cumulative ProportionMid-eye to Fork Length (cm)
0.0
0.2
0.4
0.6
0.8
1.0
30 40 50 60 70 80 90 100 110 120 130
Chinook
Caught
Radio-tagged
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Figure A-26. Cumulative length-frequency distributions for salmon captured in the Middle River, by species
and capture site, 2013.
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
Site 1
Site 2
Site 3
0.0
0.2
0.4
0.6
0.8
1.0
20 25 30 35 40 45 50 55 60 65 70
Sockeye
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65
Pink
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55 60 65 70 75
Chum
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70
Coho
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Figure A-27. Cumulative length-frequency distributions for salmon caught, radio-tagged, and spaghetti-
tagged in the Middle River, by species, 2013.
Cumulative ProportionMid-eye to Fork Length (cm)
0.0
0.2
0.4
0.6
0.8
1.0
30 40 50 60 70 80 90 100 110 120 130
Chinook
(≥ 50 cm)
Captured in the
Middle River
Radio-tagged
Spaghetti-tagged
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70 75
Sockeye
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60
Pink
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70 75 80
Chum
0.0
0.2
0.4
0.6
0.8
1.0
30 35 40 45 50 55 60 65 70
Coho
0.0
0.2
0.4
0.6
0.8
1.0
25 30 35 40 45 50 55
Chinook
(< 50 cm)
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 June 2014
PART A - APPENDIX B: DAILY FISH PASSAGE AT WEIR AND SONAR
SITES IN THE LOWER AND MIDDLE RIVERS
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FERC Project No. 14241 Part A - Appendix B – Page 1 June 2014
Table B-1. Deshka River weir daily passage rates and tag recaptures, by species, 2013.
Daily Cum.Radio Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Tags Count Count Count Count Count Count
09-Jun 43 43 0 0 0 0 0 0 0 0 0 0
10-Jun 382 425 1 0 0 0 0 0 0 0 0 0
11-Jun 141 566 1 0 0 0 0 0 0 0 0 0
12-Jun 89 655 0 0 0 0 0 0 0 0 0 0
13-Jun 206 861 2 0 0 0 0 0 0 0 0 0
14-Jun 98 959 2 0 0 0 0 0 0 0 0 0
15-Jun 89 1,048 1 0 0 0 0 0 0 0 0 0
16-Jun 155 1,203 0 0 0 0 0 0 0 0 0 0
17-Jun 262 1,465 1 0 0 0 0 0 0 0 0 0
18-Jun 174 1,639 2 0 0 0 0 0 0 0 0 0
19-Jun 44 1,683 0 0 0 0 0 0 0 0 0 0
20-Jun 110 1,793 3 0 0 0 0 0 0 0 0 0
21-Jun 752 2,545 4 0 0 0 0 0 0 0 0 0
22-Jun 1,810 4,355 14 0 0 0 0 0 0 0 0 0
23-Jun 2,583 6,938 16 0 0 0 0 0 0 0 0 0
24-Jun 481 7,419 1 0 0 0 0 0 0 0 0 0
25-Jun 3,055 10,474 23 0 0 0 0 0 0 0 0 0
26-Jun 1,313 11,787 2 0 0 0 0 0 0 0 0 0
27-Jun 1,072 12,859 10 0 0 0 0 0 0 0 0 0
28-Jun 310 13,169 4 0 0 0 0 0 0 0 0 0
29-Jun 295 13,464 1 0 0 0 0 0 0 0 0 0
30-Jun 563 14,027 6 0 0 0 0 0 0 0 0 0
01-Jul 1,158 15,185 19 0 0 0 0 0 0 0 0 0
02-Jul 215 15,400 1 0 0 0 0 0 0 0 0 0
03-Jul 474 15,874 2 0 0 0 0 0 0 0 0 0
04-Jul 842 16,716 10 0 0 0 0 0 0 0 0 0
05-Jul 557 17,273 12 0 0 0 0 0 0 0 2 2
06-Jul 529 17,802 9 0 0 0 0 0 0 0 0 2
07-Jul 37 17,839 1 0 0 0 12 12 0 0 0 2
08-Jul 8 17,847 0 0 0 0 16 28 0 0 0 2
09-Jul 63 17,910 0 0 0 0 10 38 0 0 0 2
Sockeye SalmonChinook Salmon Coho Salmon Pink Salmon Chum Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 2 June 2014
Table B-1. Continued.
Daily Cum.Radio Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Tags Count Count Count Count Count Count
10-Jul 17 17,927 0 2 2 0 3 41 0 0 0 2
11-Jul 81 18,008 0 14 16 0 0 41 0 0 0 2
12-Jul 46 18,054 0 3 19 0 4 45 0 0 0 2
13-Jul 24 18,078 0 7 26 0 8 53 0 0 0 2
14-Jul 5 18,083 0 1 27 0 7 60 0 0 0 2
15-Jul 45 18,128 0 1 28 0 10 70 0 0 0 2
16-Jul 16 18,144 0 0 28 0 3 73 0 0 0 2
17-Jul 11 18,155 0 0 28 0 9 82 0 0 0 2
18-Jul 43 18,198 0 8 36 0 5 87 0 0 0 2
19-Jul 28 18,226 0 14 50 1 13 100 6 6 3 5
20-Jul 9 18,235 0 10 60 1 45 145 0 6 0 5
21-Jul 6 18,241 0 9 69 0 553 698 2 8 1 6
22-Jul 8 18,249 0 26 95 1 584 1,282 1 9 2 8
23-Jul 16 18,265 0 12 107 0 266 1,548 0 9 0 8
24-Jul 9 18,274 0 6 113 0 353 1,901 1 10 0 8
25-Jul 2 18,276 0 2 115 0 1,842 3,743 0 10 0 8
26-Jul 5 18,281 0 10 125 0 1,407 5,150 0 10 0 8
27-Jul 5 18,286 0 11 136 0 964 6,114 0 10 0 8
28-Jul 4 18,290 0 1 137 0 281 6,395 0 10 0 8
29-Jul 4 18,294 0 3 140 0 1,537 7,932 0 10 0 8
30-Jul 2 18,296 0 0 140 0 1,439 9,371 0 10 0 8
31-Jul 2 18,298 0 0 140 0 593 9,964 0 10 0 8
01-Aug 4 18,302 0 2 142 0 260 10,224 0 10 0 8
02-Aug 12 18,314 0 11 153 0 167 10,391 1 11 0 8
03-Aug 8 18,322 0 10 163 0 211 10,602 0 11 2 10
04-Aug 6 18,328 0 58 221 0 676 11,278 0 11 1 11
05-Aug 7 18,335 0 167 388 0 2,017 13,295 0 11 4 15
06-Aug 3 18,338 0 131 519 0 4,676 17,971 0 11 4 19
07-Aug 5 18,343 0 296 815 0 2,792 20,763 1 12 2 21
08-Aug 0 18,343 0 269 1,084 0 1,603 22,366 0 12 0 21
09-Aug 1 18,344 0 616 1,700 2 749 23,115 2 14 0 21
Sockeye SalmonChinook Salmon Coho Salmon Pink Salmon Chum Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 3 June 2014
Table B-1. Continued.
Daily Cum.Radio Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Tags Count Count Count Count Count Count
10-Aug 0 18,344 0 178 1,878 0 1,384 24,499 0 14 1 22
11-Aug 0 18,344 0 539 2,417 0 320 24,819 3 17 1 23
12-Aug 49 18,393 0 8,119 10,536 21 446 25,265 5 22 3 26
13-Aug 14 18,407 0 1,519 12,055 6 155 25,420 0 22 0 26
14-Aug 8 18,415 0 1,132 13,187 3 393 25,813 0 22 0 26
15-Aug 10 18,425 0 664 13,851 2 1,173 26,986 0 22 0 26
16-Aug 4 18,429 0 484 14,335 0 198 27,184 0 22 2 28
17-Aug 6 18,435 0 1,052 15,387 3 154 27,338 1 23 0 28
18-Aug 16 18,451 0 843 16,230 2 109 27,447 3 26 2 30
19-Aug 7 18,458 0 243 16,473 1 89 27,536 1 27 0 30
20-Aug 3 18,461 0 490 16,963 3 111 27,647 0 27 0 30
21-Aug 4 18,465 0 747 17,710 3 79 27,726 3 30 1 31
22-Aug 8 18,473 0 3,745 21,455 15 31 27,757 9 39 5 36
23-Aug 11 18,484 0 430 21,885 3 21 27,778 0 39 0 36
24-Aug 9 18,493 0 31 21,916 0 23 27,801 0 39 0 36
25-Aug 10 18,503 0 25 21,941 0 83 27,884 0 39 1 37
26-Aug 9 18,512 0 48 21,989 0 11 27,895 4 43 0 37
27-Aug 5 18,517 0 19 22,008 0 3 27,898 0 43 0 37
28-Aug 5 18,522 0 30 22,038 0 4 27,902 5 48 0 37
29-Aug 1 18,523 0 25 22,063 0 10 27,912 3 51 0 37
30-Aug 3 18,526 0 16 22,079 0 5 27,917 0 51 0 37
31-Aug 3 18,529 0 10 22,089 0 7 27,924 1 52 0 37
01-Sep 0 18,529 0 9 22,098 0 4 27,928 0 52 0 37
02-Sep 2 18,531 0 42 22,140 0 1 27,929 2 54 0 37
03-Sep 0 18,531 0 1 22,141 0 0 27,929 0 54 0 37
Total 18,531 148 22,141 67 27,929 54 37
Sockeye SalmonChinook Salmon Coho Salmon Pink Salmon Chum Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 4 June 2014
Table B-2. Length statistics for tagged and untagged adult salmon sampled at the Deshka River, Montana
Creek, and Indian River weirs in 2013, by species.
Species Tagged
Not
Tagged Total Tagged
Not
Tagged Total Tagged
Not
Tagged Total
Chinook Salmon (≥ 50 cm)
Min 50 51 50 56 50 50 51 51 51
Max 96 108 108 89 105 105 96 114 114
Mean 72.0 73.4 72.9 68.1 67.2 67.3 68.0 69.8 69.7
n 148 273 421 11 207 218 80 1,131 1,211
Chinook Salmon (< 50 cm)
Min 45 45 38 38 33 24 24
Max 50 50 49 49 42 46 46
Mean 47.7 47.7 46.7 46.7 36.9 37.2 37.2
n 8 8 7 7 4 369 373
Chum Salmon (≥ 40 cm)
Min 48 44 44
Max 71 75 75
Mean 58.7 61.0 60.4
n 299 988 1,287
Coho Salmon (≥ 40 cm)
Min 40 42 40 45 43 43 44 42 42
Max 60 65 65 52 65 65 57 63 63
Mean 50.4 55.4 54.4 47.9 53.2 53.1 50.1 51.2 51.1
n 67 267 334 7 200 207 15 249 264
Pink Salmon
Min 33 29 29
Max 62 58 62
Mean 41.3 41.7 41.4
n 930 623 1,553
Sockeye Salmon (≥ 40 cm)
Min 42 42
Max 63 63
Mean 53.2 53.2
n 86 86
Notes:
Lengths are mid-eye to fork (METF).
Deshka River Weir Montana Creek Weir Indian River Weir
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FERC Project No. 14241 Part A - Appendix B – Page 5 June 2014
Table B-3. Montana Creek weir daily passage rates and tag recaptures, by species, 2013.
Daily Cum.Radio Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Tags Count Count Count Count Count Count
17-Jun 0 0 0 0 0 0 0 0 0 0 0 0
18-Jun 0 0 0 0 0 0 0 0 0 0 0 0
19-Jun 0 0 0 0 0 0 0 0 0 0 0 0
20-Jun 0 0 0 0 0 0 0 0 0 0 0 0
21-Jun 0 0 0 0 0 0 0 0 0 0 0 0
22-Jun 0 0 0 0 0 0 0 0 0 0 0 0
23-Jun 0 0 0 0 0 0 0 0 0 0 0 0
24-Jun 0 0 0 0 0 0 0 0 0 0 0 0
25-Jun 0 0 0 0 0 0 0 0 0 0 0 0
26-Jun 0 0 0 0 0 0 0 0 0 0 0 0
27-Jun 0 0 0 0 0 0 0 0 0 0 0 0
28-Jun 0 0 0 0 0 0 0 0 0 0 0 0
29-Jun 0 0 0 0 0 0 0 0 0 0 0 0
30-Jun 0 0 0 0 0 0 0 0 0 0 0 0
01-Jul 0 0 0 0 0 0 0 0 0 0 0 0
02-Jul 0 0 0 0 0 0 0 0 0 0 0 0
03-Jul 0 0 0 0 0 0 0 0 0 0 0 0
04-Jul 0 0 0 0 0 0 0 0 0 0 0 0
05-Jul 0 0 0 0 0 0 0 0 0 0 0 0
06-Jul 0 0 0 0 0 0 0 0 0 0 0 0
07-Jul 0 0 0 0 0 0 0 0 0 0 0 0
08-Jul 2 2 0 0 0 0 0 0 0 0 0 0
09-Jul 7 9 0 0 0 0 0 0 0 0 0 0
10-Jul 201 210 3 0 0 0 0 0 0 0 0 0
11-Jul 336 546 1 0 0 0 0 0 0 0 0 0
12-Jul 4 550 0 0 0 0 0 0 0 0 0 0
13-Jul 323 873 1 0 0 0 0 0 0 0 0 0
14-Jul 54 927 1 0 0 0 0 0 0 0 0 0
15-Jul 161 1,088 0 0 0 0 0 0 0 0 0 0
16-Jul 69 1,157 1 0 0 0 0 0 0 0 0 0
17-Jul 160 1,317 0 0 0 0 0 0 0 0 0 0
Chinook Salmon Coho Salmon Pink Salmon Chum Salmon Sockeye Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 6 June 2014
Table B-3. Continued.
Daily Cum.Radio Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Tags Count Count Count Count Count Count
18-Jul 96 1,413 0 0 0 0 0 0 0 0 0 0
19-Jul 8 1,421 0 0 0 0 0 0 0 0 0 0
20-Jul 20 1,441 0 0 0 0 26 26 4 4 0 0
21-Jul 70 1,511 0 0 0 0 26 52 17 21 0 0
22-Jul 73 1,584 0 0 0 0 61 113 39 60 0 0
23-Jul 13 1,597 0 0 0 0 9 122 6 66 0 0
24-Jul 21 1,618 1 0 0 0 25 147 13 79 0 0
25-Jul 103 1,721 0 0 0 0 1,420 1,567 118 197 0 0
26-Jul 181 1,902 0 0 0 0 2,380 3,947 348 545 0 0
27-Jul 12 1,914 0 0 0 0 575 4,522 86 631 0 0
28-Jul 3 1,917 1 0 0 0 77 4,599 29 660 0 0
29-Jul 4 1,921 1 0 0 0 144 4,743 23 683 0 0
30-Jul 4 1,925 0 0 0 0 38 4,781 7 690 0 0
31-Jul 3 1,928 0 0 0 0 87 4,868 185 875 0 0
01-Aug 2 1,930 0 1 1 0 217 5,085 255 1,130 0 0
02-Aug 5 1,935 0 0 1 0 115 5,200 190 1,320 0 0
03-Aug 0 1,935 0 4 5 0 312 5,512 295 1,615 0 0
04-Aug 4 1,939 0 7 12 0 266 5,778 499 2,114 0 0
05-Aug 14 1,953 0 17 29 0 498 6,276 948 3,062 0 0
06-Aug 9 1,962 0 10 39 0 307 6,583 409 3,471 0 0
07-Aug 2 1,964 0 8 47 0 136 6,719 161 3,632 0 0
08-Aug 6 1,970 0 8 55 0 122 6,841 111 3,743 0 0
09-Aug 4 1,974 0 11 66 0 387 7,228 204 3,947 0 0
10-Aug 8 1,982 0 28 94 0 499 7,727 580 4,527 0 0
11-Aug 6 1,988 0 17 111 1 126 7,853 201 4,728 0 0
12-Aug 12 2,000 0 30 141 1 169 8,022 218 4,946 0 0
13-Aug 4 2,004 0 13 154 0 192 8,214 130 5,076 0 0
14-Aug 1 2,005 0 12 166 0 227 8,441 93 5,169 0 0
15-Aug 1 2,006 1 11 177 1 401 8,842 131 5,300 0 0
16-Aug 3 2,009 0 7 184 1 101 8,943 308 5,608 0 0
17-Aug 1 2,010 0 14 198 0 149 9,092 370 5,978 0 0
Chinook Salmon Coho Salmon Pink Salmon Chum Salmon Sockeye Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 7 June 2014
Table B-3. Continued.
Daily Cum.Radio Daily Cum.Radio Daily Cum.Daily Cum.Daily Cum.
Date Count Count Tags Count Count Tags Count Count Count Count Count Count
18-Aug 2 2,012 0 7 205 0 109 9,201 337 6,315 0 0
19-Aug 1 2,013 0 10 215 0 243 9,444 137 6,452 0 0
20-Aug 1 2,014 0 454 669 2 281 9,725 288 6,740 0 0
21-Aug 0 2,014 0 0 669 0 0 9,725 0 6,740 0 0
22-Aug 0 2,014 0 0 669 0 0 9,725 0 6,740 0 0
23-Aug 0 2,014 0 0 669 0 0 9,725 0 6,740 0 0
24-Aug 0 2,014 0 0 669 0 0 9,725 0 6,740 0 0
25-Aug 0 2,014 0 0 669 0 0 9,725 0 6,740 0 0
26-Aug 0 2,014 0 4 673 0 10 9,735 21 6,761 0 0
27-Aug 1 2,015 0 8 681 0 16 9,751 40 6,801 0 0
28-Aug 0 2,015 0 16 697 0 9 9,760 67 6,868 0 0
29-Aug 0 2,015 0 17 714 0 7 9,767 37 6,905 0 0
30-Aug 0 2,015 0 15 729 0 5 9,772 31 6,936 0 0
31-Aug 0 2,015 0 10 739 0 2 9,774 26 6,962 0 0
01-Sep 0 2,015 0 26 765 0 0 9,774 31 6,993 0 0
02-Sep 0 2,015 0 0 765 0 0 9,774 0 6,993 0 0
03-Sep 0 2,015 0 0 765 0 0 9,774 0 6,993 0 0
04-Sep 0 2,015 0 0 765 0 0 9,774 0 6,993 0 0
05-Sep 0 2,015 0 0 765 0 0 9,774 0 6,993 0 0
Total 2,015 11 765 6 9,774 6,993 0
Chinook Salmon Coho Salmon Pink Salmon Chum Salmon Sockeye Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 8 June 2014
Table B-4. Indian River weir daily passage rates and tag recaptures, by species, 2013.
Daily Radio Daily Radio Daily Radio Spag.Daily Radio Spag.Daily Radio Spag.Daily Radio
Date Count Tags Count Tags Count Tags Tags Count Tags Tags Count Tags Tags Count Tags
26-Jun 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
27-Jun 13 0 0 0 0 0 0 0 0 0 0 0 0 0 0
28-Jun 1 2 0 0 0 0 0 0 0 0 0 0 0 0 0
29-Jun 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
30-Jun 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
01-Jul 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
02-Jul 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0
03-Jul 19 0 0 0 0 0 0 0 0 0 0 0 0 0 0
04-Jul 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0
05-Jul 64 2 4 0 0 0 0 0 0 0 0 0 0 0 0
06-Jul 37 4 10 0 0 0 0 0 0 0 0 0 0 0 0
07-Jul 36 2 2 0 0 0 0 0 0 0 0 0 0 0 0
08-Jul 21 4 2 0 0 0 0 0 0 0 0 0 0 0 0
09-Jul 16 1 0 0 0 0 0 0 0 0 0 0 0 0 0
10-Jul 170 16 19 0 0 0 0 0 0 0 0 0 0 0 0
11-Jul 51 2 13 0 0 0 0 0 0 0 0 0 0 0 0
12-Jul 35 3 7 1 0 0 0 0 0 0 0 0 0 0 0
13-Jul 89 4 12 1 0 0 0 0 0 0 0 0 0 0 0
14-Jul 76 9 15 0 1 0 0 0 0 0 0 0 0 0 0
15-Jul 22 0 9 1 0 0 0 0 0 0 0 0 0 0 0
16-Jul 11 3 2 0 0 0 0 0 0 0 0 0 0 0 0
17-Jul 26 1 4 0 0 0 0 0 0 0 0 0 0 0 0
18-Jul 25 2 1 0 0 0 0 0 0 0 0 0 0 0 0
19-Jul 48 5 12 0 0 0 0 0 0 0 0 0 0 0 0
20-Jul 27 1 14 0 9 0 0 6 0 0 1 0 0 9 0
21-Jul 42 2 3 0 6 0 0 3 0 0 6 0 0 11 0
22-Jul 34 0 -2 0 1 0 0 1 0 0 2 0 0 4 0
23-Jul 26 1 5 2 5 0 0 0 0 0 4 0 1 0 0
24-Jul 29 0 0 0 6 0 0 0 0 0 6 0 0 1 0
25-Jul 24 1 7 0 23 0 0 -1 0 0 5 0 0 0 0
Sockeye SalmonMETF ≥ 50 cm
Chinook Salmon
METF < 50 cm Chum Salmon Coho Salmon Pink Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 9 June 2014
Table B-4. Continued.
Daily Radio Daily Radio Daily Radio Spag.Daily Radio Spag.Daily Radio Spag.Daily Radio
Date Count Tags Count Tags Count Tags Tags Count Tags Tags Count Tags Tags Count Tags
26-Jul 14 0 6 1 74 0 1 3 0 0 17 0 1 1 0
27-Jul 17 0 18 3 128 1 10 0 0 0 27 0 1 1 0
28-Jul 12 0 23 0 314 2 12 0 0 0 74 0 0 4 0
29-Jul 13 1 10 0 609 1 21 4 0 0 172 0 5 2 0
30-Jul 22 2 14 0 884 2 13 1 0 0 408 0 14 3 0
31-Jul 8 0 16 0 637 1 20 2 0 0 421 0 17 1 0
01-Aug 3 1 5 0 637 1 20 2 0 0 707 0 44 2 0
02-Aug 15 1 7 0 705 1 28 0 0 0 1,514 0 85 4 0
03-Aug 1 0 18 2 772 0 42 2 0 0 1,828 0 115 2 0
04-Aug -4 0 8 0 660 0 26 2 0 0 2,015 0 116 0 0
05-Aug 9 1 4 0 760 17 31 11 0 0 2,619 13 144 1 0
06-Aug 14 0 5 0 730 0 35 3 1 0 2,923 0 104 13 0
07-Aug 0 0 11 2 794 0 27 17 0 0 3,288 0 213 12 0
08-Aug 17 0 8 0 604 0 4 5 0 0 3,422 1 191 4 0
09-Aug 5 0 2 0 589 0 39 16 0 0 3,128 1 190 -1 0
10-Aug 9 0 0 0 694 13 26 13 2 1 4,292 5 241 10 0
11-Aug 5 0 0 0 440 0 15 17 1 4 1,156 0 53 2 0
12-Aug 0 0 0 0 567 5 31 20 1 0 2,234 9 135 5 0
13-Aug 4 0 0 0 389 0 15 21 0 2 1,633 0 62 5 0
14-Aug 4 0 0 0 404 0 11 20 1 0 1,218 1 70 4 0
15-Aug 0 0 0 0 336 0 11 5 0 1 787 0 41 4 1
16-Aug 0 0 0 0 173 0 0 19 1 0 523 0 17 0 0
17-Aug 0 0 0 0 198 4 9 19 2 0 853 4 38 16 2
18-Aug 0 0 0 0 215 1 19 7 1 0 525 1 36 0 0
19-Aug 2 0 0 0 463 0 25 292 4 28 1,369 0 41 0 0
20-Aug 0 0 0 0 20 2 0 4 3 0 4 0 0 0 0
Total 1,137 72 294 13 12,847 51 491 514 17 36 37,181 35 1,975 120 3
Notes:
These data are net upstream counts (or net passage). Subsampled data were expanded accordingly. Only fish released at the Middle River fishwheels were included in the tag totals. Only
fish of known size category, and fish that were inspected for tags were included.
Sockeye SalmonMETF ≥ 50 cm
Chinook Salmon
METF < 50 cm Chum Salmon Coho Salmon Pink Salmon
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FERC Project No. 14241 Part A - Appendix B – Page 10 June 2014
Figure B-1. Daily amount of video imagery collected at the Indian River weir and the type of sampling
method used to review the imagery (15-min sub-sample, full-hour sample), June 26 to August 20, 2013.
0
4
8
12
16
20
24
6/266/297/27/57/87/117/147/177/207/237/267/298/18/48/78/108/138/168/19Sample Effort (h)Date (m/d)
15-min Subsample
Full-hour Sample
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FERC Project No. 14241 Part A - Appendix B – Page 11 June 2014
Figure B-2. Net passage of adult salmon that were inspected for tags, and the percent that were tagged (mark
rate), at the Indian River weir from June 26 to August 20, 2013.
Date (m/d)Net Passage (# fish)Mark Rate (%)0
10
20
30
40
0
40
80
120
160
200
6/276/307/37/67/97/127/157/187/217/247/277/308/28/58/88/118/148/178/20Inspected for Tags
Percent Tagged
Chinook
(≥ 50 cm)
The mark rate on 6/28
was excluded here (2
tagged fish passed, 1
fish was inspected)
0
5
10
15
20
25
0
1,000
2,000
3,000
4,000
5,000
6/266/297/27/57/87/117/147/177/207/237/267/298/18/48/78/108/138/168/19Pink
0
2
4
6
8
10
0
200
400
600
800
1,000
6/266/297/27/57/87/117/147/177/207/237/267/298/18/48/78/108/138/168/19Chum
0
20
40
60
80
0
60
120
180
240
300
6/266/297/27/57/87/117/147/177/207/237/267/298/18/48/78/108/138/168/19Coho
0
10
20
30
0
5
10
15
20
6/266/297/27/57/87/117/147/177/207/237/267/298/18/48/78/108/138/168/19Sockeye
0
10
20
30
40
50
0
5
10
15
20
25
6/276/307/37/67/97/127/157/187/217/247/277/308/28/58/88/118/148/178/20Chinook
(< 50 cm)
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FERC Project No. 14241 Part A - Appendix B – Page 12 June 2014
Figure B-3. Number of rainbow trout, Dolly Varden, Arctic grayling, longnose sucker, round whitefish, and
humpback whitefish counted on video imagery collected at the Indian River weir, by direction of movement,
2013.
Date (m/d)Number of Fish Counted on Underwater Video Imagery-50
-25
0
25
50 Upstream
Downstream
Rainbow Trout
-4
-2
0
2
4 Dolly Varden
-6
-3
0
3
6
9 Arctic Grayling
0
1
2
3
4 Longnose Sucker
-4
-2
0
2
4
6
8 Round Whitefish
-1
1
3
5
6/266/297/27/57/87/117/147/177/207/237/267/298/18/48/78/108/138/168/19Humpback Whitefish
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FERC Project No. 14241 June 2014
PART A - APPENDIX C: FIXED-STATION RECEIVER SITES (SETUP
AND PERFORMANCE) AND MOBILE-TRACKING SURVEY EFFORT
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FERC Project No. 14241 Part A - Appendix C – Page 1 June 2014
Table C-1. Location and antenna orientation of fixed-station receivers in the Susitna River drainage, 2013.
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 19 62.19382 -151.58783 Left 1 Downstream Yentna River
2 Upstream Yentna River
Talachulitna Weir 15 61.86028 -151.43159 Right 1 Downstream Talachulitna River
2 Upstream Talachulitna 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 46 62.55397 -150.23167 Left 1 Downstream Chulitna River
2 Upstream Chulitna River
Deshka Weir 24 61.78585 -150.34572 Right 1 Downstream Deshka River
2 Upstream Deshka River
Montana Creek Weir 45 62.10556 -150.04861 Right 1 Downstream Montana Creek
2 Upstream Montana Creek
Middle Fork Chulitna Weir 44 63.05900 -149.58222 Left 1 Downstream Middle Fork Chulitna River
2 Upstream Middle Fork Chulitna River
Montana Creek 1 62.11816 -150.03607 Left1 1 Downstream Montana Creek
2 Upstream Montana Creek
Whiskers Creek 2 105 62.37468 -150.16802 Left1 1 Downstream Whiskers Slough
2 Upstream Susitna River
3 Upstream Whiskers Slough
Lane Creek 5,10 117 62.52792 -150.11407 Right 1 Downstream Susitna River
2 Upstream Susitna River
3 Across Susitna River
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 2 June 2014
Table C-1. Continued.
Site Location
Receiver
No.
Project
River Mile Latitude Longitude River Bank Antenna Antenna Orientation
Gateway 15 130 62.67645 -149.89303 Right 1 Downstream Susitna River
2 Upstream Susitna River
4th of July Creek 17 134 62.71538 -149.80478 Right 1 Downstream Susitna River
2 Upstream Susitna River
3 Up 4th of July Creek
Indian River 25 142 62.78530 -149.65793 Right 1 Downstream Susitna River
2 Upstream Susitna River
3 Up Indian River
Upper Indian River 26,27 62.80930 -149.66245 Left1 1 Across Indian River
2 At weir
Powerline 31 146 62.81904 -149.57602 Right 1 Downstream Susitna River
2 Upstream Susitna River
Devils Island 50 167 62.80926 -149.00268 1 Downstream Susitna River
2 Upstream Susitna River
Deadman 58 191 62.82991 -148.41756 Right 1 Downstream Susitna River
2 Upstream Susitna River
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.
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 3 June 2014
Table C-2. Monitoring efficiency (percent operational) of fixed-station receivers in the Lower River Basin in 2013, by week.
Week
Lower
Yentna
Upper
Yentna
Skwentna
River
Talachulit
na River
Deshka
Mouth
Deshka
Weir
Montana
Weir
Montana
Creek
Sunshine
Mouth
Talkeetna
Station
Chulitna
Station
Middle
Chulitna
5/20 - 5/26 nd nd nd nd nd nd nd nd 100 nd nd nd
5/27 - 6/2 100 nd nd nd 100 100 nd nd 100 nd nd nd
6/3 - 6/9 100 100 100 nd 100 100 nd 100 100 nd nd nd
6/10 - 6/16 74 100 100 100 100 100 100 100 100 100 nd nd
6/17 - 6/23 100 100 100 100 100 100 100 100 100 100 nd 100
6/24 - 6/30 100 100 100 100 100 100 100 100 100 100 nd 100
7/1 - 7/7 100 100 100 100 100 100 100 100 100 100 100 100
7/8 - 7/14 100 100 100 100 100 100 100 100 100 100 100 100
7/15 - 7/21 100 100 100 100 100 100 100 100 100 100 100 100
7/22 - 7/28 100 100 100 100 100 100 100 100 100 100 100 100
7/29 - 8/4 100 100 100 100 100 100 100 100 100 100 100 100
8/5 - 8/11 100 100 100 100 100 100 100 100 100 100 100 nd
8/12 - 8/18 100 100 100 100 100 100 100 100 100 100 100 nd
8/19 - 8/25 100 100 100 100 100 100 100 100 100 100 100 nd
8/26 - 9/1 100 100 100 100 100 100 100 100 91 100 100 nd
9/2 - 9/8 100 nd nd nd 100 100 100 100 10 100 100 nd
9/9 - 9/15 100 nd nd nd 100 100 nd 100 64 nd 100 nd
9/16 - 9/22 100 nd nd nd 100 100 nd 100 100 nd 100 nd
9/23 - 9/29 100 nd nd nd 100 nd nd 100 100 nd 100 nd
Notes:
Red = full memory caused loss of data; Yellow = low power/dead battery.
Fixed-station Receiver
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.
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 4 June 2014
Table C-3. Monitoring efficiency (percent operational) of fixed-station receivers in the Middle and Upper River basins in 2013, by week.
Week
Whiskers
Creek
Lane
Station
(LR Tags)
Lane
Station
(MR Tags)Gateway
4th of July
Creek
Indian
River
Indian
Weir
(salmon)Powerline
Devils
Station
(salmon)Deadman
Kosina
Creek
Oshetna
Creek
5/27 - 6/2 nd nd nd nd nd nd nd nd nd nd nd nd
6/3 - 6/9 100 100 100 100 100 100 nd nd nd nd nd nd
6/10 - 6/16 100 100 100 100 100 100 nd 100 nd nd nd nd
6/17 - 6/23 100 100 100 100 100 100 nd 100 nd nd nd nd
6/24 - 6/30 100 100 100 100 39 100 100 38 100 nd 100 4
7/1 - 7/7 100 100 100 100 91 100 100 92 100 100 100 0
7/8 - 7/14 100 100 100 100 100 100 100 68 100 100 100 34
7/15 - 7/21 100 100 100 100 100 100 100 35 100 100 100 100
7/22 - 7/28 100 100 100 100 100 100 100 79 100 100 100 100
7/29 - 8/4 100 100 100 100 100 100 100 100 100 100 37 100
8/5 - 8/11 100 100 100 100 100 95 100 100 100 100 0 100
8/12 - 8/18 100 100 100 100 100 43 100 100 100 100 17 100
8/19 - 8/25 100 100 100 100 100 100 100 100 100 100 92 100
8/26 - 9/1 100 100 100 100 100 100 100 100 100 100 100 100
9/2 - 9/8 100 100 100 100 100 100 nd 36 100 100 100 100
9/9 - 9/15 100 100 100 100 100 100 nd 64 100 100 100 100
9/16 - 9/22 100 100 100 100 100 100 nd 100 80 nd 100 100
9/23 - 9/29 100 100 100 nd nd 100 nd nd 93 nd 100 100
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').
Gray = receiver not scanning; Red = full memory caused loss of data; Yellow = low power/dead battery.
Fixed-station Receiver
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. For hours in which no beacon tags, radio tags, or
noise events were recorded, crew notes were consulted to determine the cause of the data gap. In some instances, the receiver was determined to be fully active despite a lack of detection data
(i.e., beacon tags were malfunctioning, or poorly placed).
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 5 June 2014
Table C-4. List of the aerial telemetry surveys conducted through September 21, 2013, by location, date, and vehicle type (helicopter, fixed-wing).
Zone Name From To 6-226-236-246-256-266-286-296-307-17-27-37-47-57-67-77-87-97-107-117-127-137-147-15MOB - Little Susitna River --3
MOB - Beyond Confluence --4 F F
MOB - Confluence - Yentna 3.5 32.4 5 F F H
MOB - Yentna River 32.4 -22 H F H H F
MOB - Yentna - Deshka 32.4 45.0 35 H F H H F
MOB - Deshka River 44.9 -42 H F H H F
MOB - Willow and Little Willow 52.2 55.6 53 H F H H F/H
MOB - Kashwitna River 64.7 -54 H F H H F
MOB - Deshka - Kashwitna 45.0 64.7 55 H F H H H F
MOB - Caswell area tribs 65.8 76.3 63 F H F/H
MOB - Kashwitna - Montana 64.7 80.7 65 H F H H F H
MOB - Montana Creek 80.9 -71 H F H F H
MOB - Montana - Sunshine 80.7 88.5 75 H F H H F H
MOB - Sunshine Creek 88.1 -76 F
MOB - Rabideux Creek 87.4 -77 H F H
MOB - Talkeetna River 101.0 -81 H F H H F
MOB - Chulitna River 101.7 -83 H F F H
MOB - Sunshine - Talkeetna 88.5 102.3 85 H F H H F H
MOB - Talkeetna - Lane 102.3 116.8 95 H H H H H H
MOB - Whiskers Creek 104.8 -97 H
MOB - Trib off zone 95 110.5 -98
MOB - Lane - Gateway 116.8 130.1 105 H H H H H H H H H H H H H
MOB - Lane Creek 117.1 -106 H
MOB - 5th of July Creek 127.3 -108
MOB - Slough 8A 129.2 129.8 109
MOB - Gateway - 4th of July 130.1 134.3 111 H H H H H H H H H H H H
MOB - Slough 9 131.4 133.5 112
MOB - Sherman Creek 134.1 -114
MOB - 4th of July Creek 134.3 -116 H H H H H
MOB - 4th of July - Slough 11 134.3 140.2 117 H H H H H H H H H H H H
MOB - Slough 11 138.6 -118 H
PRM Zone
#
Survey Date (m-d)
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 6 June 2014
Table C-4. Continued.
Zone Name From To 7-167-177-187-197-207-217-227-237-247-257-267-277-287-297-307-318-18-28-38-48-58-68-7MOB - Little Susitna River --3
MOB - Beyond Confluence --4 F F
MOB - Confluence - Yentna 3.5 32.4 5 F F
MOB - Yentna River 32.4 -22 H F H H
MOB - Yentna - Deshka 32.4 45.0 35 H F H H F
MOB - Deshka River 44.9 -42 H F H H F
MOB - Willow and Little Willow 52.2 55.6 53 H F H H F
MOB - Kashwitna River 64.7 -54 F H F
MOB - Deshka - Kashwitna 45.0 64.7 55 H F H H F
MOB - Caswell area tribs 65.8 76.3 63 F H H
MOB - Kashwitna - Montana 64.7 80.7 65 H F H H F
MOB - Montana Creek 80.9 -71 H F H H
MOB - Montana - Sunshine 80.7 88.5 75 H F H H F
MOB - Sunshine Creek 88.1 -76
MOB - Rabideux Creek 87.4 -77 H
MOB - Talkeetna River 101.0 -81 H F H H F
MOB - Chulitna River 101.7 -83 F H H F
MOB - Sunshine - Talkeetna 88.5 102.3 85 H F H H F
MOB - Talkeetna - Lane 102.3 116.8 95 H H H H
MOB - Whiskers Creek 104.8 -97 H H
MOB - Trib off zone 95 110.5 -98
MOB - Lane - Gateway 116.8 130.1 105 H H H H
MOB - Lane Creek 117.1 -106 H H H H
MOB - 5th of July Creek 127.3 -108
MOB - Slough 8A 129.2 129.8 109 H H H
MOB - Gateway - 4th of July 130.1 134.3 111 H H H H
MOB - Slough 9 131.4 133.5 112 H H H
MOB - Sherman Creek 134.1 -114 H H
MOB - 4th of July Creek 134.3 -116 H H H H
MOB - 4th of July - Slough 11 134.3 140.2 117 H H H H
MOB - Slough 11 138.6 -118 H H
PRM Zone
#
Survey Date (m-d)
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 7 June 2014
Table C-4. Continued.
Zone Name From To 8-88-98-108-118-128-138-168-178-198-208-238-248-258-268-278-308-319-29-39-49-59-209-21MOB - Little Susitna River --3
MOB - Beyond Confluence --4 F F F
MOB - Confluence - Yentna 3.5 32.4 5 F F F
MOB - Yentna River 32.4 -22 F F H H H F F
MOB - Yentna - Deshka 32.4 45.0 35 H H H F H F F
MOB - Deshka River 44.9 -42 H H H F H F F
MOB - Willow and Little Willow 52.2 55.6 53 H H H F H F F
MOB - Kashwitna River 64.7 -54 H H H F H F F
MOB - Deshka - Kashwitna 45.0 64.7 55 H H H F H F F
MOB - Caswell area tribs 65.8 76.3 63 F H H F F F
MOB - Kashwitna - Montana 64.7 80.7 65 H H H F H F F
MOB - Montana Creek 80.9 -71 F H H H F H F F
MOB - Montana - Sunshine 80.7 88.5 75 H H H F H F F
MOB - Sunshine Creek 88.1 -76 H H H H
MOB - Rabideux Creek 87.4 -77 H H H
MOB - Talkeetna River 101.0 -81 H H H F H F F
MOB - Chulitna River 101.7 -83 H H H F H F F
MOB - Sunshine - Talkeetna 88.5 102.3 85 H H H F H H F F
MOB - Talkeetna - Lane 102.3 116.8 95 H H H H H H
MOB - Whiskers Creek 104.8 -97 H H H H H H H H H
MOB - Trib off zone 95 110.5 -98 H H H H H H H
MOB - Lane - Gateway 116.8 130.1 105 H H H H H H H H
MOB - Lane Creek 117.1 -106 H H H H H H H H
MOB - 5th of July Creek 127.3 -108 H H H H H
MOB - Slough 8A 129.2 129.8 109 H H H H H H H H
MOB - Gateway - 4th of July 130.1 134.3 111 H H H H H H H H
MOB - Slough 9 131.4 133.5 112 H H H H H H H H
MOB - Sherman Creek 134.1 -114 H H H
MOB - 4th of July Creek 134.3 -116 H H H H H H H H
MOB - 4th of July - Slough 11 134.3 140.2 117 H H H H H H H H
MOB - Slough 11 138.6 -118 H H H H H H H H
Survey Date (m-d)PRM Zone
#
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 8 June 2014
Table C-4. Continued.
Zone Name From To 9-239-249-279-3010-110-210-710-910-2110-2210-2310-24MOB - Little Susitna River --3
MOB - Beyond Confluence --4
MOB - Confluence - Yentna 3.5 32.4 5 H
MOB - Yentna River 32.4 -22 H H H
MOB - Yentna - Deshka 32.4 45.0 35 H H H
MOB - Deshka River 44.9 -42 H H H
MOB - Willow and Little Willow 52.2 55.6 53 H H H
MOB - Kashwitna River 64.7 -54 H H
MOB - Deshka - Kashwitna 45.0 64.7 55 H H H
MOB - Caswell area tribs 65.8 76.3 63 H
MOB - Kashwitna - Montana 64.7 80.7 65 H H H
MOB - Montana Creek 80.9 -71 H H H H
MOB - Montana - Sunshine 80.7 88.5 75 H H H H
MOB - Sunshine Creek 88.1 -76 H
MOB - Rabideux Creek 87.4 -77 H H H H
MOB - Talkeetna River 101.0 -81 H H H H
MOB - Chulitna River 101.7 -83 H H H H
MOB - Sunshine - Talkeetna 88.5 102.3 85 H H H H
MOB - Talkeetna - Lane 102.3 116.8 95 H H H H H H
MOB - Whiskers Creek 104.8 -97 H H H H
MOB - Trib off zone 95 110.5 -98 H
MOB - Lane - Gateway 116.8 130.1 105 H H H H
MOB - Lane Creek 117.1 -106 H H H H
MOB - 5th of July Creek 127.3 -108
MOB - Slough 8A 129.2 129.8 109 H H H H
MOB - Gateway - 4th of July 130.1 134.3 111 H H H H
MOB - Slough 9 131.4 133.5 112 H H H
MOB - Sherman Creek 134.1 -114
MOB - 4th of July Creek 134.3 -116 H H H H
MOB - 4th of July - Slough 11 134.3 140.2 117 H H H H
MOB - Slough 11 138.6 -118 H H H H
PRM
Zone
#
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 9 June 2014
Table C-4. Continued.
Zone Name From To 6-226-236-246-256-266-286-296-307-17-27-37-47-57-67-77-87-97-107-117-127-137-147-15MOB - Gold Creek 140.1 -119
MOB - Slough11 - Indian 140.1 142.1 125 H H H H H H H H H H H H H H
MOB - Indian trib 141.8 -132 H H H H H H H H H H H
MOB - Indian - Slough 21 142.1 145.7 135 H H H H H H H H H H H H
MOB - Slough 21 145.1 145.6 136
MOB - above Powerline 145.7 146.0 138 H H H H H H H H H H H
MOB - abv Powerline - Portage 146.0 152.3 145 H H H H H H H H H H H H H H H H H
MOB - Jack Long Creek 148.2 -146 H H H H H
MOB - Portage trib 152.3 -152 H H H H H H H H H H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 153 H H H H H H H H H H H H H H H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.4 157 H H H H H H H H H H H H H H H H H H H H H
MOB - Cheechako Creek 155.9 -158 H H H H H H H H H H H H H H H H H H H H
MOB - Cheechako - Impediment2 157.4 160.2 163 H H H H H H H H H H H H H H H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.5 167 H H H H H H H H H H H H H H H H H H H H H
MOB - Chinook Creek 160.4 -168 H H H H H H H H H H H H H H H H H H H H
MOB - Chinook - Impediment3 160.5 164.8 173 H H H H H H H H H H H H H H H H H H H H H
MOB - Devils Creek 164.8 -176 H H H H H H H H H H H H H H H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 177 H H H H H H H H H H H H H H H H H H H H H
MOB - Devil Stn - Fog 166.9 179.4 185 H H H H H H
MOB - Fog Creek 179.3 -192 H
MOB - Fog - Dam Site 179.4 186.8 195 H H H H H
MOB - Tsusena Creek 184.5 -197 H
MOB - Dam Site - Deadman 186.8 189.4 201 H H H H H
MOB - Deadman Creek 189.3 -203
MOB - Deadman - Watana 189.4 196.9 205 H H H H
MOB - 'Creek 192'194.8 -207
MOB - Watana Creek 196.8 -212
MOB - Wantana - Kosina 196.9 209.3 215 H
MOB - Kosina Creek 209.1 -222 H
MOB - Kosina - Oshetna 209.3 235.2 225 H H
MOB - Oshetna River 235.1 -232
MOB - above Oshetna 235.2 321.1 235
PRM Zone
#
Survey Date (m-d)
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 10 June 2014
Table C-4. Continued.
Zone Name From To 7-167-177-187-197-207-217-227-237-247-257-267-277-287-297-307-318-18-28-38-48-58-68-7MOB - Gold Creek 140.1 -119 H H H
MOB - Slough11 - Indian 140.1 142.1 125 H H H H H
MOB - Indian trib 141.8 -132 H H H H H
MOB - Indian - Slough 21 142.1 145.7 135 H H H H H H
MOB - Slough 21 145.1 145.6 136 H H H H H
MOB - above Powerline 145.7 146.0 138 H H H H H H
MOB - abv Powerline - Portage 146.0 152.3 145 H H H H H H
MOB - Jack Long Creek 148.2 -146 H H H
MOB - Portage trib 152.3 -152 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 153 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.4 157 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Cheechako Creek 155.9 -158 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Cheechako - Impediment2 157.4 160.2 163 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.5 167 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Chinook Creek 160.4 -168 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Chinook - Impediment3 160.5 164.8 173 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Devils Creek 164.8 -176 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 177 H H H H H H H H H H H H H H H H H H H H H H H
MOB - Devil Stn - Fog 166.9 179.4 185 H H H H H H H H H H H H H H H H H H
MOB - Fog Creek 179.3 -192 H H H
MOB - Fog - Dam Site 179.4 186.8 195 H H H H H H H H H H H H H H H H
MOB - Tsusena Creek 184.5 -197 H H H H H H H H H H H H H
MOB - Dam Site - Deadman 186.8 189.4 201 H H H H H H H H H H H
MOB - Deadman Creek 189.3 -203 H H
MOB - Deadman - Watana 189.4 196.9 205 H H H H H H H
MOB - 'Creek 192'194.8 -207
MOB - Watana Creek 196.8 -212 H H
MOB - Wantana - Kosina 196.9 209.3 215 H H H H H H H
MOB - Kosina Creek 209.1 -222 H H
MOB - Kosina - Oshetna 209.3 235.2 225 H H H H
MOB - Oshetna River 235.1 -232 H H H
MOB - above Oshetna 235.2 321.1 235 H H H H H H H H H H H H H
PRM Zone
#
Survey Date (m-d)
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 11 June 2014
Table C-4. Continued.
Zone Name From To 8-88-98-108-118-128-138-168-178-198-208-238-248-258-268-278-308-319-29-39-49-59-209-21MOB - Gold Creek 140.1 -119 H H H H H H H H
MOB - Slough11 - Indian 140.1 142.1 125 H H H H H H H H H
MOB - Indian trib 141.8 -132 H H H H H H H H H
MOB - Indian - Slough 21 142.1 145.7 135 H H H H H H H H
MOB - Slough 21 145.1 145.6 136 H H H H H H H H
MOB - above Powerline 145.7 146.0 138 H H H H H H H H
MOB - abv Powerline - Portage 146.0 152.3 145 H H H H H H H H
MOB - Jack Long Creek 148.2 -146 H H H H H H H H
MOB - Portage trib 152.3 -152 H H H H H H H H H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 153 H H H H H H H H H H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.4 157 H H H H H H H H H H H H H H H H
MOB - Cheechako Creek 155.9 -158 H H H H H H H H H H H H H H H
MOB - Cheechako - Impediment2 157.4 160.2 163 H H H H H H H H H H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.5 167 H H H H H H H H H H H H H H H H
MOB - Chinook Creek 160.4 -168 H H H H H H H H H H H H H H H
MOB - Chinook - Impediment3 160.5 164.8 173 H H H H H H H H H H H H H H H H
MOB - Devils Creek 164.8 -176 H H H H H H H H H H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 177 H H H H H H H H H H H H H H H
MOB - Devil Stn - Fog 166.9 179.4 185 H H H H
MOB - Fog Creek 179.3 -192 H H H H
MOB - Fog - Dam Site 179.4 186.8 195 H H H H
MOB - Tsusena Creek 184.5 -197 H H H H
MOB - Dam Site - Deadman 186.8 189.4 201 H H H H
MOB - Deadman Creek 189.3 -203 H H H H
MOB - Deadman - Watana 189.4 196.9 205 H H H H
MOB - 'Creek 192'194.8 -207 H H H
MOB - Watana Creek 196.8 -212 H H H H
MOB - Wantana - Kosina 196.9 209.3 215 H H H H
MOB - Kosina Creek 209.1 -222 H H H H
MOB - Kosina - Oshetna 209.3 235.2 225 H H H H
MOB - Oshetna River 235.1 -232 H H H H
MOB - above Oshetna 235.2 321.1 235
Survey Date (m-d)PRM Zone
#
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix C – Page 12 June 2014
Table C-4. Continued.
Zone Name From To 9-239-249-279-3010-110-210-710-910-2110-2210-2310-24MOB - Gold Creek 140.1 -119 H H H H
MOB - Slough11 - Indian 140.1 142.1 125 H H H H
MOB - Indian trib 141.8 -132 H H H
MOB - Indian - Slough 21 142.1 145.7 135 H H H H
MOB - Slough 21 145.1 145.6 136 H H H H
MOB - above Powerline 145.7 146.0 138 H H H H
MOB - abv Powerline - Portage 146.0 152.3 145 H H H H
MOB - Jack Long Creek 148.2 -146 H H H
MOB - Portage trib 152.3 -152 H H H H H H H
MOB - Portage - Impediment1 152.3 155.2 153 H H H H H H H
MOB - Impediment1 - Cheechako 155.2 157.4 157 H H H H H H H
MOB - Cheechako Creek 155.9 -158 H H H H H H H
MOB - Cheechako - Impediment2 157.4 160.2 163 H H H H H H H
MOB - Impediment2 - Chinook 160.2 160.5 167 H H H H H H H
MOB - Chinook Creek 160.4 -168 H H H H H H H
MOB - Chinook - Impediment3 160.5 164.8 173 H H H H H H
MOB - Devils Creek 164.8 -176 H H H H H H
MOB - Impediment3 - Devil Stn 164.8 166.9 177 H H H H H
MOB - Devil Stn - Fog 166.9 179.4 185 H H H H
MOB - Fog Creek 179.3 -192 H H H H
MOB - Fog - Dam Site 179.4 186.8 195 H H H H
MOB - Tsusena Creek 184.5 -197 H H H H
MOB - Dam Site - Deadman 186.8 189.4 201 H H H H
MOB - Deadman Creek 189.3 -203 H H H
MOB - Deadman - Watana 189.4 196.9 205 H H H H
MOB - 'Creek 192'194.8 -207
MOB - Watana Creek 196.8 -212 H H H H
MOB - Wantana - Kosina 196.9 209.3 215 H H H H
MOB - Kosina Creek 209.1 -222 H H H H
MOB - Kosina - Oshetna 209.3 235.2 225 H H H H
MOB - Oshetna River 235.1 -232 H H H H
MOB - above Oshetna 235.2 321.1 235
PRM
Zone
#
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 June 2014
PART A - APPENDIX D: SPAWNING DESTINATIONS
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix D – Page 1 June 2014
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), 2013.
Survey Date Presence Spawning Presence Spawning Presence Spawning
13-Aug
Indian River Delta X X X
4th of July Slough/Side Channel X
14-Aug
Slough 10 X X
Slough 8A X X X X X
15-Aug
4th of July Slough/Side Channel X X X
16-Aug
Slough 1
Slough 2
Slough 4
Slough 5
Slough 6A
Oxbow 1
Slough ?1 X X X
18-Aug
Slough 21
Side Channel 21 X X
Slough 20
Slough 17
Slough 14
Slough 11 X X
Slough 9A X X
Slough 9 X X X X X
01-Sep
Slough 21A X X X X X
slough 21 X X
slough 22 X X X X X
Slough 19 X
Slough 11 X X X X
Slough 10 X X X X X
02-Sep
Slough 9A X X X X
5th of July Slough X X
Slough ?1 X X
Sockeye Pink Chum
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FERC Project No. 14241 Part A - Appendix D – Page 2 June 2014
Table D-2. Summary of monitoring effort at potential spawning sites for Chinook salmon in the Middle River, 2013.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Migrating Holding Spawning
1 295 Lane Creek Tributary Delta NA NA
2a,b 696 Lane Creek - Gateway Mainstem 24-Jul Boat
3b 783 Lane Creek - Gateway Mainstem 24-Jul ARIS X
4b 516 Lane Creek - Gateway Mainstem 24-Jul Boat
5a 739 Gateway - Slough 11 Mainstem 26-Jul Boat
6 731 4th of July Creek Tributary Delta 24-Jul ARIS X
27-Jul Boat X
31-Jul ARIS X
7a 548 Gateway - Slough 11 Mainstem 27-Jul Boat
8a 474 Gateway - Slough 11 Mainstem 27-Jul Boat
9 Cluster Indian River Tributary Delta 25-Jul ARIS X X X
31-Jul ARIS X X
10a 723, 734 Side Channel 21 Side Channel *Aerial
11a 346, 328 Slough 21 - Portage Creek Mainstem 31-Jul Boat
12c Cluster Portage Creek Tributary Delta 31-Jul ARIS/Visual X X
13 254 Chinook Creek Tributary Delta *Aerial
a Indicates a site that was visually assessed and considered too difficult to sample with ARIS.
b Indicates a site that was visually assessed and not considered suitable for spawning based on physical characteristics.
c Indicates a site where sonar detected fish, but species could not be determined.
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Site not surveyed
Too turbid to assess
Site not surveyed
Too turbid to assess
Fish Observed
Site not visited
Site not surveyed
Site not surveyed
Site not surveyed
Site not surveyed
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Part A - Appendix D – Page 3 June 2014
Table D-3. Summary of monitoring effort at potential spawning sites for chum salmon in the M iddle River, 2013.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Migrating Holding Spawning
1 2908, 3808, 5247 Slough 8A Side Slough 14-Aug HSC X X
16-Sep HSC X
29-Sep HSC X
2 Cluster Slough 9 Side Slough 18-Aug HSC X X
17-Sep HSC X
3b 2079 Gateway - Slough 11 Mainstem *Aerial/Boat
4b 2291 Gateway - Slough 11 Mainstem *Aerial/Boat
5 3502 Gateway - Slough 11 Side Slough 07-Sep Aerial X X
6 3631 Slough 9A Side Slough 18-Aug HSC X
02-Sep HSC X X
29-Sep HSC X
7a 2578 Indian River - Slough 21 Side Channel *Aerial
8 3596 Side Channel 21 Side Channel 18-Aug HSC X X
01-Sep HSC X X
15-Sep HSC X
28-Sep HSC X
9 4483 Jack Long Creek Tributary Delta 01-Sep HSC X
*Aerial X
a Indicates a site that was visually assesed and considered too difficult to sample with ARIS
b Indicates a site that was visually assessed and not considered suitable for spawning based on physical characteristics
c Indicates a site where sonar detected fish, but species could not be determined
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Fish Observed
Site not surveyed
Site not surveyed
Site not surveyed
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix D – Page 4 June 2014
Table D-4. Summary of monitoring effort at potential spawning sites for pink salmon in the Middle River, 2013.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Migrating Holding Spawning
1 2972 Lane Creek Tributary Delta 13-Aug HSC X X
2b 3876 Lane Creek - Gateway Mainstem *Boat/Aerial
3 2255 5th of July Creek Tributary Delta 02-Sep HSC X
4b 2059 Gateway - Slough 11 Mainstem *Boat/Aerial
5c 1498, 2106, 2302 4th of July Creek Tributary Delta 31-Jul ARIS X X
12-Aug ARIS X X
6c 8188 4th of July Side Channel Side Channel 31-Jul ARIS X X
13-Aug ARIS X X
7b,c 1571 Gateway - Slough 11 Mainstem 31-Jul ARIS X
*Aerial
8 Cluster Indian River Tributary Delta 12-Aug HSC X X X
13-Aug HSC X X X
9c 2306, 2349 Portage Creek Tributary Delta 31-Jul ARIS X X
31-Jul Visual X X
a Indicates a site that was visually assesed and considered too difficult to sample with ARIS
b Indicates a site that was visually assessed and not considered suitable for spawning based on physical characteristics
c Indicates a site where sonar detected fish, but species could not be determined
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Fish Observed
Site not Surveyed
Site not Surveyed
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Part A - Appendix D – Page 5 June 2014
Table D-5. Summary of monitoring effort at potential spawning sites for sockeye salmon in the Middle River, 2013.
Habitat Survey Survey
Site #Fish #Location Type Date Type None Migrating Holding Spawning
1 2568 Slough 8B Side Slough *Aerial X
2 4533 Skull Creek Tributrary Delta 07-Sep Aerial X X
14-Sep HSC X X
30-Sep HSC X X
3b 4060 Lane Creek - Gateway Mainstem *Boat
4 Cluster Slough 8A Side Slough 14-Aug HSC X X
29-Sep HSC X X
5a,b 3390 Gateway - Slough 11 Side Channel *Boat/Aerial
6 Cluster Slough 9 Side Slough 18-Aug HSC X
17-Sep HSC X
7c 4553, 4347 4th of July Side Channel Side Channel 31-Jul ARIS X X
13-Aug ARIS X X
17-Sep HSC X
8b 2516 Gateway - Slough 11 Mainstem *Boat/Aerial
9 4034 Slough 9A Side Slough 18-Aug HSC X
02-Sep HSC X X
10 Cluster Slough 10 Upland Slough 14-Aug HSC X
01-Sep HSC X X
11 Cluster Slough 11 Upland Slough 18-Aug HSC X
01-Sep HSC X X
12 1982, 2896 Slough/Side Channel 21 Side Channel 18-Aug HSC X
01-Sep HSC X
15-Sep HSC X X
28-Sep HSC X X
13c 1041, 2900 Portage Creek Tributary Delta 31-Jul ARIS X X
a Indicates a site that was visually assesed and considered too difficult to sample with ARIS
b Indicates a site that was visually assessed and not considered suitable for spawning based on physical characteristics
c Indicates a site where sonar detected fish, but species could not be determined
* Indicates a site that was monitored on a regular basis, but spawning was not observed or confirmed. Most are turbid water locations.
Fish Observed
Site not surveyed
Site not surveyed
Site not surveyed
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Part A - Appendix D – Page 6 June 2014
Table D-6. Details of impediment-passage events for radio-tagged fish, 2013.
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)
241 13 Jul 14 Jul 16 Jul 1.0 0.5 2.0 14,383 15,410 16,672
272 13 Jul 14 Jul 30 Jul 8.5 0.5 16.0 14,383 15,410 18,848
395 11 Jul 12 Jul 13 Jul 3.0 1.0 1.5 16,876 15,058 14,383
Average 12 Jul 13 Jul 19 Jul 4.2 0.7 6.5 15,214 15,293 16,634
Chinook Salmon (≥ 50 cm) that Passed Impediment 2 but not Impediment 3
254 12 Jul 13 Jul -6.0 0.5 1.5 15,058 14,383 -
280 13 Jul 13 Jul -1.0 0.5 4.5 14,383 14,383 -
309 12 Jul 13 Jul -6.0 0.5 1.5 Mort *15,058 14,383 -
355 14 Jul 16 Jul -6.0 1.0 13.0 15,410 16,672 -
418 13 Jul 13 Jul -4.0 0.0 4.0 14,383 14,383 -
528 16 Jul 19 Jul -2.5 3.5 9.5 16,672 19,202 -
555 24 Jul 24 Jul -1.5 0.5 4.8 16,884 16,884 -
658 12 Jul 12 Jul -3.0 0.5 17.0 15,058 15,058 -
715 13 Jul 14 Jul -5.0 0.5 16.5 14,383 15,410 -
798 14 Jul 14 Jul -2.0 0.5 14.5 15,410 15,410 -
6535 12 Jul 13 Jul -2.5 0.5 0.5 15,058 14,383 -
6604 17 Jul 18 Jul -2.0 0.5 4.5 15,872 17,353 -
7082 13 Jul 14 Jul -1.5 0.5 9.0 14,383 15,410 -
Average 14 Jul 15 Jul 3.3 0.7 8.3 15,232 15,640
Chinook Salmon (≥ 50 cm) that Passed Impediment 1 but not Impediment 2
219 †30 Jun --4.0 d.n.a.-25,352 --
278 13 Jul --4.0 d.n.a.-14,383 --
353 14 Jul --2.5 1.0 -15,410 --
593 16 Jul --7.0 1.5 -16,672 --
Average 12 Jul 4.4 1.3 17,954
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Part A - Appendix D – Page 7 June 2014
Table D-6. Continued.
Chinook Salmon (≥ 50 cm) that Approached Impediment 1 but didn't 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)
176 †---2.5 -----
178 ---4.0 -----
210 ---2.0 -----
224 †---4.0 -----
299 ---11.5 -----
328 ---6.0 -----
332 ---3.0 -----
338 ---2.0 -----
347 ---6.0 -----
404 ---1.0 -----
447 ---2.0 -----
479 ---3.5 -----
501 ---5.5 -----
517 ---3.0 -----
524 ---2.0 -----
532 ---5.0 -----
541 ---6.0 -----
543 ---1.0 -----
550 ---2.5 -----
564 ---1.0 -----
615 ---1.0 -----
632 ---2.0 -----
671 ---2.0 -----
700 ---4.0 -----
714 ---1.0 -----
746 ---1.5 -----
760 ---3.0 -----
762 ---0.5 -----
764 ---1.0 -----
781 ---7.0 -----
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix D – Page 8 June 2014
Table D-6. Continued.
Chinook Salmon (≥ 50 cm) that Approached Impediment 1 but didn't 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)
815 ---1.0 -----
880 ---4.0 -----
920 ---3.5 -----
925 ---2.0 -----
927 ---10.5 -----
951 ---2.0 -----
962 ---0.5 -----
1004 ---4.5 Mort *-----
1039 ---1.0 -----
1056 ---3.5 -----
1061 ---1.5 -----
1081 ---3.5 -----
1149 ---2.0 -----
6811 †---1.5 -----
6866 ---7.0 -----
6885 ---1.0 -----
7063 ---7.0 -----
7203 ---1.0 -----
7255 ---4.5 -----
7281 ---1.0 -----
Average 3.2
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix D – Page 9 June 2014
Table D-6. Continued.
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)
1024 26 Jul --6.0 d.n.a.-17,386 --
Average 26 Jul 6.0 17,386
Chinook Salmon (< 50 cm) that Approached Impediment 1 but didn't Pass
635 ---2.5 -----
638 ---0.5 -----
713 ---0.5 -----
717 ---2.0 -----
959 ---0.5 -----
1117 ---1.5 -----
Average 1.3
Sockeye Salmon that Approached Impediment 1 but didn't Pass
898 ---5.5 -----
1074 ---0.5 -----
1093 ---0.5 -----
2011 †---9.0 -----
2216 ---0.5 -----
2414 †---8.0 -----
2724 †---3.5 -----
2900 †---2.0 -----
3831 ---0.5 -----
Average 3.3
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
Susitna-Watana Hydroelectric Project Alaska Energy Authority
FERC Project No. 14241 Part A - Appendix D – Page 10 June 2014
Table D-6. Continued.
Coho Salmon that Approached Impediment 1 but didn't 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)
2522 ---1.0 -----
2705 †---4.5 -----
2805 †---2.0 -----
3304 ---1.0 -----
3511 †---2.0 -----
3626 †---3.5 -----
Average 2.3
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. Fish that died while holding below an
impediment were not included in calculations of average hold time. Hold times for fish noted with a dagger (†) were interpolated since surveys were not conducted
every day during the period when the fish was present. 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 passed Impediment 1 but
not Impediment 2. Sixth panel: Chinook salmon (< 50 cm) that approached within 1 km of Impediment 1, but did not pass. Seventh panel: sockeye salmon that
approached within 1 km of Impediment 1, but did not pass. Eighth panel: coho salmon that approached within 1 km of Impediment 1, but did not pass.
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Part A - Appendix D – Page 11 June 2014
Table D-7. Number of Chinook salmon counted during aerial spawner surveys, by location and survey
period, 2013.
Survey 1 Survey 2 Survey 31 Survey 42 Survey 53
(July 19-21)(July 25-27)(Aug 1-3)(Aug 8-10)(Aug 14-16)
Cheechako 5 40 24 16 1
Chinook 0 2 1 0 0
Devil 7 25 15 12 0
Fog 0 1 0 2 2
Fog L1 0 0 0 0 0
PRM 184.0 0 0 0 0 0
PRM 184.0 R1 0 0 0 0 0
Tsusena 0 0 0 4 2
Deadman 0 0 0 0 0
Watana 0 0 0 0 0
Watana R5 0 0 0 0 0
Kosina 2 3 0 0 0
Gilbert 0 0 0 0 0
Tsisi 0 0 0 0 0
Tsisi Lakes 0 0 0 0 0
Jay 0 0 0 0 0
Goose 0 0 0 0 0
Oshetna 0 0 0 0 0
Black 0 0 0 0 0
Susitna 0 0 0 0 0
Indian River -
above weir 336 363 192 69 1
Indian River -
below weir 90 90 14 2 0
Notes:
1 An estimated 2,600 other salmon (1,650 below weir): 85 percent pink, 10 percent chum, 5 percent sockeye salmon.
2 An estimated 4,475 pink (2,355 below weir), 1,310 chum (20 below weir), and 35 sockeye (19 below weir) salmon.
3 An estimated 1,355 pink (1,030 below weir), 80 chum (0 below weir), and 3 sockeye (0 below weir) salmon.
Stream
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Part A - Appendix D – Page 12 June 2014
Table D-8. Summary of weather variability during the adult salmon aerial spawner surveys in the Middle
and Upper rivers, 2013.
Table D-9. Summary of survey condition rankings during the adult salmon aerial spawner surveys in the
Middle and Upper rivers, 2013.
Date Sunny
Partly
Cloudy Overcast
Light
Rain Rain Wind
July 19–21 x x x x
July 25–27 x x x x
August 1–2 x x x
August 8–9 x x x x
August 15–16 x x x
Weather Condition
Variable Average Rank
Reported
Range
Standard
Deviation
Sun Glare 2.8 1 to 4 0.55
Water clarity 2.8 0 to 4 1.32
Vegetation Cover 2.5 0 to 4 0.94
Notes:
Variables were ranked from 0 to 4, with 4 being optimal and 0 being poor.
INITIAL STUDY REPORT SALMON ESCAPEMENT STUDY (9.7)
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FERC Project No. 14241 Part A - Appendix D – Page 13 June 2014
Figure D-1. Relative frequencies of tributary use by radio-tagged salmon released in the Lower River, by
species, 2013.
Relative Frequency0%
5%
10%
15%
20%
25%
30%
35%Chinook Salmon
0%
5%
10%
15%
20%
25%
30%
35%Yentna RiverDeshka RiverWillow Ck.Little Willow Ck.Kashwitna Ck.Goose Ck.Sheep Ck.Montana Ck.Talkeetna RiverChulitna RiverLane Ck.5th of July Ck.4th of July Ck.Gold Ck.Indian RiverJack Long Ck.Portage Ck.Devil Ck.Cheechako Ck.Chinook Creek.Tsusena Ck.OtherStock
Pink Salmon
0%
5%
10%
15%
20%
25%
30%
35%Coho Salmon
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FERC Project No. 14241 Part A - Appendix D – Page 14 June 2014
Figure D-2. Potential mainstem spawning sites for radio-tagged Chinook salmon in the Lower River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 15 June 2014
Figure D-3. Potential mainstem spawning sites for radio-tagged coho salmon in the Lower River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 16 June 2014
Figure D-4. Potential mainstem spawning sites for radio-tagged coho salmon in the Middle River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 17 June 2014
Figure D-5. Potential mainstem spawning sites for radio-tagged pink salmon in the Lower River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 18 June 2014
Figure D-6. Potential mainstem spawning sites for radio-tagged pink salmon in the Middle River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 19 June 2014
Figure D-7. Relative frequencies of tributary use by radio-tagged salmon released in the Middle River, by
species, 2013. Relative Frequency0%
15%
30%
45%
60%Chinook Salmon (≥ 50 cm)
0%
15%
30%
45%
60%Pink Salmon
0%
15%
30%
45%
60%Chinook Salmon (< 50 cm)
0%
15%
30%
45%
60%Chum Salmon
0%
15%
30%
45%
60%Yentna RiverDeshka RiverWillow Ck.Little Willow Ck.Kashwitna Ck.Goose Ck.Sheep Ck.Montana Ck.Talkeetna RiverChulitna RiverLane Ck.5th of July Ck.4th of July Ck.Gold Ck.Indian RiverJack Long Ck.Portage Ck.Devil Ck.Cheechako Ck.Chinook Creek.Tsusena Ck.OtherStock
Sockeye Salmon
0%
15%
30%
45%
60%Coho Salmon
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FERC Project No. 14241 Part A - Appendix D – Page 20 June 2014
Figure D-8. Potential mainstem spawning sites for radio-tagged Chinook salmon in the Middle River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 21 June 2014
Figure D-9. Potential mainstem spawning sites for radio-tagged chum salmon in the Lower River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 22 June 2014
Figure D-10. Potential mainstem spawning sites for radio-tagged chum salmon in the Middle River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 23 June 2014
Figure D-11. Potential mainstem spawning sites for radio-tagged sockeye salmon in the Lower River, 2013.
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FERC Project No. 14241 Part A - Appendix D – Page 24 June 2014
Figure D-12. Potential mainstem spawning sites for radio-tagged sockeye salmon in the Middle River, 2013.
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Figure D-13. Summary of Chinook salmon observations during aerial spawner surveys in the Middle and Upper rivers, 2013. All survey observations
were combined; and observation points may represent multiple fish.
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PART A - APPENDIX E: RADIO TAG RECOVERIES
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Table E-1. Tag recovery information for fish released in the Lower River and Yentna River, 2013.
Tag Date Recovery
Species Number Recovered Description Latitude Longitude Method
Chinook Salmon 6547 7 Aug Willow Creek 100 yd upstream of railroad bridge 61.7658 -150.0417 Field Crews
(METF ≥ 50 cm)6561 12 Aug Indian Weir 62.8124 -149.6624 Field Crews
6570 11 Aug Indian Weir 62.8124 -149.6624 Field Crews
6628 22 Jun Deshka river mile 6 61.7735 -150.3419 Field Crews
6649 6 Aug Prairie Cr.62.6167 -149.0554 Field Crews
6687 24 Jun Willow mouth 61.7785 -150.1662 Field Crews
6734 24 Jun Willow mouth 61.7785 -150.1662 Field Crews
6882 30 Jun Deshka River mile 2 61.7294 -150.3192 Field Crews
7105 1 Jul Deshka River mile 2 61.7294 -150.3192 Field Crews
7124 8 Jul Deshka R., above weir (RM7)61.7886 -150.3398 Field Crews
7126 5 Jul mouth of Peters Cr.62.1765 -150.8787 Field Crews
7131 7 Jul mouth of Clear Cr.62.3799 -150.0162 Field Crews
7227 13 Jul Peters Cr., 5 mi. downstream of Forks Roadhouse 62.3053 -150.7257 Field Crews
7258 22 Jun Deshka ~1 mi. upstream 61.7121 -150.3238 Field Crews
7263 25 Jul Indian Weir 62.8124 -149.6624 Field Crews
7397 26 Jun Lake Cr. near mouth 61.9092 -150.9096 Field Crews
7588 1 Jul Talachulitna river mile 1 61.8564 -151.3886 Field Crews
7637 1 Jul Johnson Creek (Yentna tributary)62.0655 -151.6068 Field Crews
7744 7 Jul Moose Cr. (Yentna trib.)61.7971 -150.6966 Field Crews
7803 21 Jun 8 Mile Cr. on Skwentna R.61.9548 -151.1964 Field Crews
7825 5 Jul Lake Creek near Yenlo Creek 62.0627 -150.9906 Field Crews
7881 3 Sep Lake Creek, ~6 miles downstream from Chelatna Lake 62.3664 -151.2955 Field Crews
7959 26 Jun Lake Cr. near mouth 61.9092 -150.9096 Field Crews
8005 22 Jun Lake Cr. river mile 1.5 61.9307 -150.9127 Field Crews
8017 5 Jul Lake Creek near Yenlo Creek 62.0627 -150.9906 Field Crews
Recovery Location1
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Table E-1. Continued.
Tag Date Recovery
Species Number Recovered Description Latitude Longitude Method
Coho salmon 6006 19 Aug Peters Creek 62.3053 -150.7257 Field Crews
6012 13 Sep Chase Cr, middle Susitna ~2 mi. downstream of Lane Cr.62.4956 -150.0951 Field Crews
6038 4 Aug Sustina River at Susitna Landing (Kashwitna confluence)61.9110 -150.1033 Field Crews
6106 10 Aug Caswell Creek mouth 61.9392 -150.0839 Field Crews
6131 21 Aug Susitna River, mouth of Trapper Creek 62.2578 -150.1685 Field Crews
6133 15 Aug Clear Creek (Talkeetna River)62.3799 -150.0162 Field Crews
6151 18 Aug Malone Slough (Yentna R. near Johnson C. confluence)62.0841 -151.4969 Field Crews
6200 7 Aug Talachulitna river at Friday Creek 61.7108 -151.4597 Field Crews
6212 20 Aug Johnson Creek (Yentna tributary)62.0655 -151.6068 Field Crews
6238 14 Aug Sheep Creek mouth 61.9712 -150.0875 Field Crews
6241 1 Aug mouth of Caswell Cr.61.9392 -150.0839 Field Crews
6256 20 Aug Yentna River 61.7971 -150.6966 Field Crews
6309 3 Aug Deshka mouth 61.6976 -150.3173 Field Crews
6349 3 Aug Yentna River, 20-mile Slough 61.8265 -150.7918 Field Crews
6410 10 Aug Caswell Creek mouth 61.9392 -150.0839 Field Crews
6460 22 Aug Clear Creek (Talkeetna River)62.3799 -150.0162 Field Crews
6490 13 Aug Deshka River, ~RM 4 61.7475 -150.3215 Field Crews
6491 17 Aug Lake Creek mouth 61.9092 -150.9096 Field Crews
7422 17 Aug Clear Creek (Talkeetna River)62.3799 -150.0162 Field Crews
7433 6 Aug Sunshine Creek (Susitna trib.)62.1782 -150.1032 Field Crews
7496 19 Aug Talachulitna River 61.8564 -151.3886 Field Crews
1 Recovery coordinates are estimates, based on the site description.
Recovery Location1
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Table E-2. Tag recovery information for fish released in the Middle River, 2013.
Tag Date Recovery
Species Number Recovered Description Latitude Longitude Method
Chinook Salmon 178 31 Jul Portage Creek 62.8367 -149.3729 Field Crews
(METF ≥ 50 cm)214 14 Jul no info --Field Crews
298 1 Aug Indian Weir 62.8124 -149.6624 Field Crews
305 17 Jul Above Indian Weir 62.8112 -149.6592 Field Crews
348 16 Jul Indian Weir 62.8124 -149.6624 Field Crews
387 24 Aug no info --Field Crews
440 5 Aug Indian Weir 62.8124 -149.6624 Field Crews
479 30 Jul Portage Mouth 62.8290 -149.3800 Field Crews
569 12 Aug Indian Weir 62.8124 -149.6624 Field Crews
578 24 Jul Indian Weir 62.8124 -149.6624 Field Crews
718 3 Aug Troublesome Creek 62.6687 -150.2250 Angler
727 5 Jul Fishwheel Site 1 Curry 62.6165 -150.0161 Field Crews
744 16 Jul Indian Weir 62.8124 -149.6624 Field Crews
777 22 Jul Indian Weir 62.8124 -149.6624 Field Crews
789 24 Jul Above Indian Weir 62.8112 -149.6592 Field Crews
805 18 Jul Indian Weir 62.8124 -149.6624 Field Crews
812 2 Aug Indian Weir 62.8124 -149.6624 Field Crews
841 22 Jul Chulitna River 62.4910 -150.2480 Field Crews
897 11 Aug Indian Weir 62.8124 -149.6624 Field Crews
955 20 Jul Indian Weir 62.8124 -149.6624 Field Crews
993 22 Jul Indian Weir 62.8124 -149.6624 Field Crews
1003 3 Aug Indian Weir 62.8124 -149.6624 Field Crews
1062 5 Aug Indian Weir 62.8124 -149.6624 Field Crews
1123 29 Jul Indian Weir 62.8124 -149.6624 Field Crews
Recovery Location1
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Table E-2. Continued.
Tag Date Recovery
Species Number Recovered Description Latitude Longitude Method
Chinook salmon 491 21 Jul Spink Creek (Chulitna)62.7280 -150.2410 Angler
(METF < 50 cm)1024 11 Aug Indian Weir 62.8124 -149.6624 Field Crews
1067 14 Aug Indian Weir 62.8124 -149.6624 Field Crews
1117 3 Aug Indian Weir 62.8124 -149.6624 Field Crews
1138 30 Jul Indian Weir 62.8124 -149.6624 Field Crews
1157 7 Sep West bank of Susitna 62.3238 -150.1381 Angler
Pink salmon 1503 14 Aug Indian Weir 62.8124 -149.6624 Field Crews
1504 14 Aug 1/2 mile up Indian River 62.7918 -149.6615 Field Crews
1986 23 Aug Fishwheel Site 3 Curry 62.6374 -149.9775 Field Crews
2094 7 Aug RM 138 - sandbar 62.7840 -149.6630 Angler
2106 2 Aug Slough 8A 62.6641 -149.9053 Field Crews
2157 17 Aug RM 148 62.8280 -149.4530 Field Crews
2321 18 Aug Indian Weir 62.8124 -149.6624 Field Crews
2586 11 Aug Slough 8A 62.6709 -149.9000 Field Crews
2595 8 Aug Indian Weir 62.8124 -149.6624 Field Crews
2770 no info Fishwheel Site 3 Curry 62.6374 -149.9775 Field Crews
3490 28 Aug 5th of July 62.6536 -149.9578 Field Crews
Sockeye salmon 3863 no info Slough 8A 62.6666 -149.8932 Field Crews
Chum salmon 1855 10 Aug Indian Weir 62.8124 -149.6624 Field Crews
1980 13 Aug Indian Weir 62.8124 -149.6624 Field Crews
2116 2 Aug Indian Weir 62.8124 -149.6624 Field Crews
2196 10 Aug Indian Weir 62.8124 -149.6624 Field Crews
2502 12 Aug Fishwheel Site 3 Curry 62.6374 -149.9775 Field Crews
3877 13 Aug Clear Creek 62.4950 -149.8770 Angler
4106 17 Aug Montana Creek weir 62.1056 -150.0486 Field Crews
Recovery Location1
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Table E-2. Continued.
Tag Date Recovery
Species Number Recovered Description Latitude Longitude Method
Coho salmon 2739 17 Aug Mouth of Indian 62.7853 -149.6582 Field Crews
4917 28 Aug Whiskers Creek 62.3747 -150.1690 Field Crews
2721 8 Aug Sunshine 62.1850 -150.1410 Angler
2732 15 Aug Lake Creek (Yentna)61.9440 -150.9130 Angler
2711 20 Aug Clear Creek 62.4950 -149.8770 Angler
1 Recovery coordinates are estimates, based on the site description.
Recovery Location1
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PART A - APPENDIX F: TRACKING HISTORIES OF CHINOOK SALMON
ABOVE IMPEDIMENT 3
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Table F-1. Summary of migration and spawning behavior for three radio-tagged Chinook salmon after they passed Impediment 3, 2013.
Max Max Max Max Total
Tag Capture METF Spawning First Last Upstream Upstream Downstream Downstream Live
Number Date (cm)Sex Area Live Live Days Location Distance Days Location Distance Days Days1
241 21-Jun 64 Undetermined Unknown -30-Aug -Near headwater --Below Talkeetna --45
272 23-Jun 64 Undetermined Devils 30-Jul 12-Aug 14 Devils Creek 0 0 Devils Creek 0 0 13
395 26-Jun 65 Undetermined Tsesena 22-Jul 01-Aug 11 near Deadman Creek 6.5 1 Tsusena Creek 0 0 19
Average 26-Jul 14-Aug 12.5 3.25 0.5 0 0 25.7
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 #241) that was detected above Impediment 3, 2013.
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Figure F-2. Tracking history of a radio-tagged Chinook salmon (tag #272) that was detected above Impediment 3, 2013.
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Figure F-3. Tracking history of a radio-tagged Chinook salmon (tag #395) that was detected above Impediment 3, 2013.
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PART A - APPENDIX G: FEASIBILITY STUDY ASSESSING FISH
COUNTS WITH SONAR IN WATANA CANYON, 2013
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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 not well understood.
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 2013, 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 into the project area.”
Assessing the potential to accurately count fish requires a number of different considerations,
including physical site characteristics, the ability to effectively operate gear, and whether the
counts are indices, estimates, or a complete census. The life history and behavior of each fish
species can further affect these considerations – resident fish, for example, can migrate both
upstream and downstream, and thus may require a different study design than salmon migrating
only upstream.
AEA followed up on FERC’s recommendation by evaluating the feasibility of using sonar to
detect and count fish in the Watana Canyon area in July of 2013. AEA chose multi-beam
imaging sonar because it provided the highest likelihood of being able to observe fish behavior
and movement, and, to a lesser extent identify species or species groups. As stated in Section
4.3.4, a weir was deemed physically impossible due to the high volume and variability of water
flow (summer flows in Watana Canyon range from about 15,000 to over 40,000 cfs), depth, and
complex bathymetry.
This report describes the site feasibility study in July of 2013, evaluates the ability to count fish
given site conditions and other considerations, and describes the plans for 2014.
1.1. Study Objectives
The specific objectives for this feasibility study were:
1. Identify suitable deployment sites and verify that multi-beam imaging sonar can detect
fish in Watana Canyon near the Watana Dam site.
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2. Combine field results with study design considerations to evaluate the potential for using
sonar to accurately count fish species migrating upstream through Devils Canyon and
into the Watana Canyon area.
3. Describe logistical considerations and equipment necessary to establish a monitoring
station, if sonar counts of fish were determined to be feasible.
2. STUDY AREA
The study area was in the Watana Canyon reach of the Susitna River near the proposed Watana
Dam site, between PRM 184 and PRM 187 (Figure G-1). Lack of CIRWG land access limited
study sites to places where a helicopter could land below mean high water (MHW). Additional
criteria for site selection included the presence of a level area above MHW that could be used to
operate electronic equipment if the site were chosen for future use, laminar water flow, a river
bottom with a consistent, gradual slope, and a width narrow enough to be completely ensonified
by sonar directed from shore. These latter features are usually found in straight, moderately
constrained stretches of river with a gravel bottom and no bedrock outcrops.
3. METHODS
The Watana Canyon reach was surveyed by helicopter on July 19, 2013 to locate potential sites
for installing an Adaptive Resolution Imaging Sonar (ARIS) system to monitor fish. Three sites
were chosen, each of which was evaluated for one day from July 20–23 (Figure G-1). All
fieldwork, including helicopter landings, was done below the MHW of the Susitna River. Each
site was then assessed for overall suitability for future sonar studies.
Sonar imaging was conducted using an ARIS 1200 (www.soundmetrics.com) mounted to an
aluminum H-mount frame (Photo G-1). The ARIS 1200 can be operated with two different
frequencies (1.2 and 0.7 megahertz [MHz]) and has a sample volume defined with a 29 degree
(horizontal) by 14 degree (vertical) field of view. Maximum range for viewing fish measuring
26 in or greater in length is about 200 ft. The ARIS system consisted of a sonar head, 50 ft data
transmission cable, topside switch box, Ethernet cable, Toughbook laptop computer, and
portable external hard drives. The system was powered by a gasoline-powered Honda 2000
generator. Data were collected using ARIScope software in consecutive 10-minute files, and the
system was typically configured to use an imaging frame rate of between four and seven frames
per second. Both operational frequencies (0.7 and 1.2 MHz) were used at each site. All data
were ported directly to the external hard drives, and backed up and archived to additional hard
drives.
Data were processed using ARISFish software (www.soundmetrics.com) to assess fish presence.
Processed data were reviewed in echogram mode, which allowed entire 10-minute data files to
be viewed on the computer screen with time on the X-axis and sonar range on the Y-axis. Fish
present in the data were shown as echo traces. When traces were observed, the data segment
containing the trace was played back in streaming data mode, which allowed direction of travel
and fish length to be characterized.
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4. RESULTS
4.1. Site Characteristics
The ARIS was tested on one day at each of three sites in the Watana Canyon Area, for three to
five hours at each site (Table G-1; Figure G-1). The three sites were selected based on access
permission and the basic shoreline criteria described above. Additional potential study sites
likely existed, but were not accessible because they would have required a helicopter landing
above MHW. River discharge during the July 19–23 study period decreased from 21,840 to
16,953 cfs over the four-day study period, based on data from the Tsusena Creek gauge (Figure
G-2; data obtained from http://waterdata.usgs.gov/usa/nwis/uv?15291700).
All sites had a helicopter landing zone (LZ) below MHW, and suitable areas above MHW for a
battery bank and electronics. Site locations, physical characteristics, and basic testing details are
provided in Figure G-1 and Table G-1. The ARIS was deployable and operable at each site. The
ARIS detected multiple species of fish at Site 1, demonstrating that Objective 1 (detection of fish
in the Watana Canyon area using sonar) is technically feasible. Each site, however, presented its
own set of challenges that must be addressed before Objective 2 (accurately counting fish) can
be met. These challenges differ for the type of counts and the species of interest.
Site 1 was near PRM 184, approximately 3 miles downstream from the proposed Watana Dam
site (Photo G-2). A dry gravel beach extended 65 ft from MHW on the river right bank (looking
downstream) to the water’s edge (Photo G-3). The ARIS was operated at the wetted edge of this
beach on July 20 from 10:15 to 14:15, for a total of four hours. The ARIS was able to ensonify
most of the water column (proportion of the water column ensonified is unknown since water
depth during the time of the survey was also unknown) out to halfway across the river (98 of 196
ft). Substrate could be seen in the field of view out to 98 ft in range. The inability to see
substrate beyond this indicated a change in bed slope. Along river left, velocities were high and
a large boulder caused rapids. It is conceivable that the swift water could deflect upstream-
moving fish to the calmer water on river right, where they would be ensonified; if so, all fish
moving upstream at this site could be counted. The low frequency setting provided better
resolution (more clear imagery of the substrate and water column) than did the high-resolution
setting. This was likely the result of greater amounts of noise generated with the high frequency
setting associated with the turbid water conditions. The low frequency setting afforded a greater
signal to noise ratio than did the high frequency setting.
Site 2 was just upstream of the Watana Dam site near PRM 187 (Figure G-1; Photo G-4). The
river had an approximately 262 ft wetted channel at this site (Photo G-4). The ARIS was placed
on the river right bank and operated on July 21 from 10:15 to 14:20, for a total of 4.08 hours.
The ARIS was able to sample out to 20 m (65 ft) before the channel slope increased, based on
how far substrate could be seen in the field of view (Photo G-5). As with Site 1, the low
frequency setting provided better resolution than did the high frequency setting. Approximately
60 m (192 ft) of the river cross section was outside of field of view, based on substrate in the
sample volume. Although the field of view was not as long as at Site 1, it may be possible to
operate a second ARIS from the opposite bank at Site 2. This second ARIS would need to have
a field of view of approximately 200 ft to ensonify all potential fish; this distance is within the
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specifications of the ARIS, but would require a favorable river bed topography (flat to gradually
sloping).
Site 3 was located at PRM 187.8 (Figure G-1; Photo G-6). The wetted channel was
approximately 134 ft wide (Photo G-6). The ARIS was operated from the river left bank on July
22 from 11:03 to 14:10, for a total of 3.12 hours. The ARIS was able to see the river bottom for
only 4 m (13 ft) before the channel slope increased. As at Site 2, ensonification of the river
channel would require a second ARIS unit operated from river left, with a gradual enough bed
slope to allow a field of view of approximately 120 ft.
4.2. Detection of Fish with Sonar
Fish were detected at Site 1, where the imagery showed promise for counting fish if suitable
locations or designs can be identified. At Site 1, three distinct large fish greater than 80 cm (31
in) in estimated total length passed between 12 m (39 ft) and 16 m (52 ft) from shore all moving
upstream (e.g., Figure G-3). Based on their body length it is likely these fish were Chinook
salmon Oncorhynchus tshawytscha. Other fish (typically five to eight individuals) from 20 cm
(7 in) to 40 cm (15 in) in total length were observed milling within the sonar sample volume for
the entire data collection period. Most of the milling fish were between 3 m (9 ft) and 12 m (39
ft) from shore. Thirty fish were caught by angling in the vicinity of this site in an attempt to
identify the ensonified fish; all thirty were Arctic grayling Thymallus arcticus. No fish were
observed in the sonar beyond a sonar range of 16 m (52 ft).
4.3. Accurate Counts of Fish
The entire river channel could not be ensonified at any of the three sites using a single ARIS
unit. Other forms of sonar (such as non-imaging) would also be limited by the bed slope
bathymetry at these sites. The three main options for using sonar to attain fish counts appear to
be (1) finding another site where the river bed slopes more gradually than at the sites tested in
2013, (2) to use multiple ARISs in combination at one site (with overlapping fields of view), or
(3) to use ARIS in combination with another method such as mark recapture. Adult Chinook
salmon can probably be distinguished from other species due to their longer body length; all
other fishes would need to be actively sampled to identify to species. If complete counts of
fishes are not required, indices could be developed for some or all fish. The development of
indices would be most consistent at Site 1 due to the high water velocities offshore and the
likelihood that fish would be more bank-oriented, and thus more likely to be ensonified.
5. DISCUSSION
5.1. Site Feasibility
The three sites tested in this study were the most promising of those where access was permitted.
It is likely that there are other equally good or superior sites that would be feasible if access
above the MHW in the Watana Canyon reach was permitted by landowners. The ARIS 1200 has
a maximum range of about 200 ft for detection of fish less than 26 inches in length, but in a
riverine application such as the Susitna River in Watana Canyon, the bottom profile may limit
this range. None of the three sites tested had suitable underwater bed slopes for verifying
distances beyond 98 ft (substrate was clearly seen up to this point). Substrate visibility is a
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critical feature of sonar monitoring sites to ensure that low-lying channels or troughs are not
present in the substrate where fish might move undetected by the sonar.
Based on the testing in 2013, the inability to ensonify the entire river width in the Watana
Canyon area can be broken down into the following short list of potential solutions:
1. Find an alternate site with a bed slope and streamside features suitable for using a single
ARIS to ensonify the entire river. This seems unlikely, given the river’s width.
2. Find a site in which two ARIS units operated from opposite banks can have overlapping
fields of view. This seems more likely to be feasible.
3. Demonstrate at Site 1 (or elsewhere) that the rapid on river left pushes upstream-
migrating fish to river right, into the beam of an ARIS operated from that shore. This has
potential and may be supported by published studies from elsewhere and by on-site water
velocity measurements, but could remain vulnerable to changes in water levels during
low-flow periods.
In addition to being able to ensonify the desired river width, a suitable site will also have to be
accessible by air (i.e., a viable LZ), and have an area above MHW able to house the equipment
(two areas if using the ARIS on opposite banks).
5.2. Fish Image Detection
Within the field of view, the ARIS was able to effectively detect fish (Site 1). The ARIS was
able to document fish movement direction, another essential component. Importantly, some
targets were distinctly larger than others, indicating that adult Chinook salmon greater than 20 in
METF length can be differentiated by their larger body size from resident fish species. This
differentiation relies on the assumption that Chinook salmon are the only salmon species present
above Devils Canyon. All historic fish data as well as fish sampling and radio telemetry studies
conducted by AEA in 2012 and 2013 indicate that this assumption is accurate. The ARIS will
not be able to differentiate among most other fish species. ARIS may be able to identify the
group of species with anguilliform (sinuous) swimming motions, such as burbot Lota lota and
Arctic lamprey Lethenteron camtschaticum and Pacific lamprey Lampetra tridentate. While
burbot are known to be present in the Upper River, lamprey species have not been documented
above Devils Canyon. The common approach in mixed species environments is to use direct
capture methods to apportion species, and apply this apportionment to sonar counts to yield an
estimate of the total number of each fish species present (e.g., Westerman and Willette 2013).
To summarize, it is likely that the ARIS alone can provide counts of Chinook salmon larger than
20 inches; for most other fish, ARIS images will need to be paired with direct capture sampling
to determine species composition. Finally, future sonar work will also need to assess the
detectability of fish at range to properly calibrate counts. The detectability of fish will likely
decline with distance from the sonar; there are ways to quantify this phenomenon, usually
involving multiple sonar units at different ranges from shore.
Direct capture sampling to estimate the species composition of fish besides Chinook salmon is a
common need in sonar studies; potential direct capture sampling methods to use in Watana
Canyon include beach seining and drift or set gillnet sampling. Sampling could be used
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periodically (e.g., daily or weekly) throughout the sonar operation period. Once apportioned to
species, sonar counts of anadromous fish could be developed for corresponding time periods.
5.3. Using Sonar to Accurately Count Fish
It is possible the ARIS can be used to generate counts of adult salmon in Watana Canyon, but it
is unlikely to be feasible for resident fish for several reasons. First, there would be no effective
way to count resident fish holding below or above the sonar site. Second, a resident fish would
only be counted if it migrated past the sonar, and the migration times of various species of
resident fish are temporally separated such that operation of the sonar would be required year-
round. Freeze-up in the fall would limit the operational period of the sonar. Neither of these
limitations applies to adult salmon because they all originate from downstream, and because the
possible migration upstream would be during the open water period.
Accurate (i.e., unbiased) counts of fish would require either a complete census or some means of
estimation. A complete census would require ensonifying the entire river width, as described in
Section 5.1. The two best options for counting Chinook salmon in Watana Canyon are to find a
place where ARIS can cover the entire river channel, or to demonstrate that swift-moving water
such as the rapids at Site 1 push upstream-moving fish into a part of the channel that can be
entirely ensonified. This latter approach would require testing of the assumption that the rapids
pose a velocity barrier under all relevant flow conditions.
An estimate would require subsampling part of the river, but must be paired with other
information to know how the number of fish in the sub-sample (e.g., the ensonified area)
represents the entire fish population. Two common approaches to estimation are to expand the
sub-sample counts by a quantity thought to represent the unsampled area, and to use any of
several forms of mark-recapture methods. Both approaches have been used extensively to count
fish in riverine applications similar to Watana Canyon. Both hold promise, but are sufficiently
complicated that a full discussion is beyond the scope of this report. In each case, the species
apportionment sampling discussed in Section 5.2 would still be needed (except for large Chinook
salmon).
The mark-recapture approach for estimating total fish abundance is possible because salmon are
already being marked downstream with radio tags as part of the Escapement Study (Study 9.7).
At Watana Canyon, a combination of telemetry receivers, the ARIS, and both marked and
unmarked salmon would be used to assess sonar efficiency and ultimately expand sonar counts to
estimate total abundance. This is most feasible with relatively low numbers of salmon passing
the site each hour. Further simplifying this approach, it is likely that only Chinook salmon
migrate through Watana Canyon en route to spawning destinations. Juvenile and adult Chinook
salmon are the only salmon species confirmed to be in the Upper River by historic studies,
ADF&G studies and AEA’s extensive radio tagging and fish sampling studies conducted in 2012
and 2013. If other salmon species migrate through Watana Canyon, then alternate sampling
methods would be needed to apportion fish counts to species.
One alternative to both complete counts and estimates of salmon abundance is to provide an
index over time and a minimum estimate of salmon abundance; this would be more feasible, and
may be sufficient to meet the intent of the FERC recommendation.
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5.4. Using Fish Counts at Watana Canyon to Estimate Fish Migrating Through Devils
Canyon
Part of FERC’s recommendation was that AEA evaluate the ability to use the Watana Canyon
site(s) to count fish able to migrate up through Devils Canyon. Taken literally, this would
require counting fish, by species, migrating through Devils Canyon and then reaching Watana
Canyon. This would also require adjusting for additions and subtractions (e.g., due to spawning
and/or movement between tributaries and the mainstem river), and would be beyond the scope of
a weir or sonar site at Watana Canyon alone. For resident fish, a sonar monitoring station
located in Watana Canyon can only be used to assess numbers of resident fish that use the reach;
it would not be able to assess whether these fish originated from above or below Devils Canyon.
5.5. Logistical Needs for Future Work
The 2013 sonar site selections and assessments were limited to locations with a gravel bar to
accommodate a helicopter landing and sonar operation below MHW during a 4-day period.
Other sites likely exist within the area of interest, but further assessment requires permission for
access above MHW
A two-person crew would be needed to set up, operate and maintain the monitoring station(s).
Daily site visits by helicopter (approximately 15 minutes each way) would be required to
maintain the sonar system(s), switch out and backup external hard drives and conduct direct
capture sampling.
Each ARIS system (sonar head, data transmission cable, sonar switch box, laptop computer, and
multiple portable external hard drives), fabricated aluminum mount, also requires twelve 6-volt
AGM sealed batteries, a 2,000-Watt gas generator and a 15-gallon fuel containment unit housed
above the MHW mark. A sheltered platform is needed to house the electronic equipment. A
small boat with an outboard motor would be necessary to tend and maintain the systems at both
sites and conduct the direct capture sampling.
6. CONCLUSIONS AND RECOMMENDATIONS
The ARIS technology could be used to count fish in Watana Canyon, but providing an accurate
count for Chinook salmon is more feasible and likely to be more effective than providing counts
for other species. Providing an accurate count will require more assessment to find a site where
the entire river channel slopes gradually enough to be ensonified; alternatively, an area where
high water velocity pushes fish to a part of the river that can be ensonified would work as well.
If other salmon species are present in Watana Canyon, active sampling methods would be
needed to apportion fish counts to species. Although commonly done in other riverine sonar
applications for salmon, this species apportionment would require a substantial amount of
additional effort. In conclusion, sonar counts of fish in Watana Canyon are much more feasible
for Chinook salmon than for other anadromous or resident fish species.
During the next study year, implementation in late June or early July may enable a sonar unit to
count Chinook salmon in mid-to late July and early August, when the Chinook salmon run
presumably passes through Watana Canyon. The plan for project implementation in June of the
next study year is as follows:
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1. Determine whether the scope of fish counts can be limited to index and minimum counts,
and whether the target species can be limited to Chinook salmon. Such limitations would
then affect feasibility plans and sonar sampling design.
2. Clarify whether the location in Watana Canyon matters – e.g., upstream or downstream
of the proposed dam site and major tributaries such as Tsusena Creek.
3. Obtain land access to more sites.
4. Perform aerial reconnaissance of the study area in early June, when water levels are low
and provide the best view of channel configuration. From these, determine whether to
attempt ensonification of the entire channel or a portion.
5. Measure water velocity at key site/sites in July to bolster any assumptions about fish use
of offshore areas beyond any potential reach of the sonar.
6. Mobilize a crew and gear near the site, using daily site visits through the migration
period.
Table G-1. Characteristics of three sites surveyed with ARIS in July, 2013.
Site Date Lat Long
River
Discharge
(cfs)
Wetted
Channel
Width (ft)
Maximum
Field of
View (ft)
Hours of
Video
Collected
Fish
Detected
1 20-Jul 62.81917 -148.64011 21,837 196 98 4.00 yes
2 21-Jul 62.82312 -148.53665 21,312 257 65 4.08 no
3 22-Jul 62.82582 -148.52315 18,634 134 13 3.12 no
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Figure G-1. Location of study sites in the Watana Canyon reach of the Susitna River for evaluating
feasibility of sonar for counting fish, July, 2013. Site 1 is located near PRM 184 and the dam site is located
near PRM 187.1. Flow is from right to left.
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Figure G-2. Susitna River discharge at the US Geological Survey (USGS) gauge at Tsusena Creek for the
period July 1 through August 31, 2013. The dates when the sonar feasibility study was conducted are shown
with the gray column.
10,000
15,000
20,000
25,000
30,000
35,000
40,000
7/1 7/7 7/13 7/19 7/25 7/31 8/6 8/12 8/18 8/24 8/30Discharge (cfs)Date (m/d)
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Figure G-3. Series of still images (top left to right then bottom left to right) that show an adult Chinook
salmon (inside the white circles) migrating through the ARIS sonar sample volume in Watana Canyon at Site
1 on July 20, 2013. Flow is from left to right. The fish is estimated to be 95 cm (37 in) TL. The white objects
in the foreground are cobble on the river substrate. Note range bands are shown in 1-m (3.3 ft) increments.
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Photo G-1. Aluminum H-mount frame used to deploy the ARIS 1200 sonar at Site 1 during the Watana
Canyon sonar feasibility study, July, 2013.
Photo G-2. Aerial view of Site 1 from the sonar feasibility study, July 22, 2013. Direction of river flow is
from bottom to top of the photo. A conceptual depiction of ARIS sonar sampling area is shown with black
triangle; actual sample volume is an expanding trapezoid with the longest axis in the upstream-downstream
direction. River discharge at the time the photograph was taken was 18,634 cfs at the Tsusena Creek gage.
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Photo G-3. Ortho-rectified aerial photograph of Site 1 assessed for sonar monitoring suitability in the
Watana Canyon reach of the Susitna River, July, 2013. The line projecting from shore depicts the effective
range (30 m [98 ft]) of the sonar tested during the feasibility study.
Photo G-4. Aerial view of Site 2 of the sonar feasibility study, July, 2013. Direction of river flow is from
bottom to top of the photo. A conceptual depiction of ARIS sonar sampling area is shown with black
triangle; actual sample volume is an expanding trapezoid with the longest axis in the upstream-downstream
direction. River discharge at the time the photograph was taken was 21,313 cfs at the Tsusena Creek gage.
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Photo G-5. Ortho-rectified aerial photographs of Site 2 assessed for sonar monitoring suitability in the
Watana Canyon reach of the Susitna River, 2013. The line projecting from the sample site location depicts
the effective range (20 m [65 ft]) of the sonar tested during the feasibility study.
Photo G-6. Ortho-rectified aerial photographs of Site 3 assessed for sonar monitoring suitability in the
Watana Canyon reach of the Susitna River, 2013. The line projecting from the sample site location depicts
the effective range (4 m [13 ft]) of the sonar tested during the feasibility study.
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PART A - APPENDIX H: ABUNDANCE ESTIMATES FOR CHINOOK,
PINK, AND CHUM SALMON ABOVE CURRY AND CHINOOK SALMON
ABOVE DEVILS CANYON
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Table H-1. Estimated observer efficiencies during aerial spawner surveys for Chinook salmon conducted by
AEA and ADF&G upstream of the Indian River weir on July 25, 2013.
AEA ADF&G AEA ADF&G
1,094 784 363 281 46.3 35.8
Notes:
a On July 25, 71.7 percent (43 of 60) of all radio-tagged Chinook salmon last detected upstream of the weir were emitting a 'live' signal.
Number of Fish Counted Above the
Weir During Aerial Spawner Survey
Estimated Observer
Efficiency (%)Net Passage at
the Weir (July 25)
Estimated
Number of Live
Fish Above Weir a
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Table H-2. Recapture matrix for large Chinook salmon radio-tagged at the Middle River fishwheels, and inspected for tags at the Indian River weir,
2013.
Not Recapture
26 27 28 29 30 31 32 33 34 Recaptured Recaptured Marked a Rate
25 2 2 1 1 6 49 55 0.109
26 1 2 20 4 1 28 169 197 0.142
27 2 11 12 1 2 28 115 143 0.196
28 3 2 5 30 35 0.143
29 1 1 1 1 4 5 9 0.444
30 0 5 5 0.000
31 1 1 0 1 1.000
32 0 0 0
33 0 0 0
34 0 0 0
Marked 3 6 32 21 4 5 1 0 0 72 373 445 0.162
Unmarked 11 139 386 214 182 69 49 13 2 1,065
Inspected 14 145 418 235 186 74 50 13 2 1,137
Mark rate 0.214 0.041 0.077 0.089 0.022 0.068 0.020 0.000 0.000 0.063
Notes:
Bold numbers were used in contingency table tests (Chi-square) to evaluate whether mark and recapture rates varied by week. Adjacent shaded cells were pooled.
Period of Recapture (Statistical Week)Period of Marking
(Statistical Week)
a 91 of the 536 large Chinook salmon released at the Middle River fishwheels were never detected at or above the Middle River Gateway fixed station; and these fish were censored from
the marked sample.
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Table H-3. Estimated abundance of large Chinook, chum, and pink salmon above the Middle River Gateway
fixed station (PRM 130.1), 2013.
Large
Chinook
Salmon
Parameters/Statistics
Radio
Tags
Radio
Tags
Spaghetti
Tags All Tags
Radio
Tags
Spaghetti
Tags All Tags
Tags Released at Curry 536 201 1,962 2,163 200 9,108 9,308
Tags that Entered the Study Area (M) a 445 149 1,365 1,514 151 6,736 6,887
Inspected at the Indian River Weir (C)1,137 12,906 12,906 12,906 37,181
Tagged Fish Recaptured at the Weir (R)72 51 491 542 35 1,975 2,010
Abundance Estimate (N) b 6,952 37,231 35,834 36,010 156,990 126,768 127,353
Standard Error (SE)782 5,104 1,583 1,511 25,797 2,774 2,761
Lower 95% Confidence Limit 5,536 28,448 32,807 33,108 113,760 121,301 121,909
Upper 95% Confidence Limit 8,724 48,660 39,140 39,166 216,041 132,480 133,041
Notes:
b For chum and pink salmon, abundance estimates were generated using radio- and spaghetti-tagged fish separately, as well as by pooling both
tag types.
Chum Salmon Pink Salmon
a Radio-tagged fish not detected at or above the Middle River Gateway fixed station were censored from the marked sample (M). The weekly
proportions of radio-tagged chum and pink salmon censored from the marked sample were used to estimate the number of spaghetti-tagged fish
that entered the study area.
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Table H-4. Recapture matrix for chum salmon radio-tagged at the Middle River fishwheels and inspected for tags at the Indian River weir, 2013.
Not Recapture
26 27 28 29 30 31 32 33 34 Recaptured Recaptured Marked a Rate
25 0 0 0
26 0 0 0
27 0 0 0
28 0 1 1 0.000
29 0 2 2 0.000
30 1 6 7 1 15 12 27 0.556
31 2 21 3 1 27 50 77 0.351
32 2 5 1 8 23 31 0.258
33 1 1 8 9 0.111
34 0 2 2 0.000
Marked 0 0 0 0 1 8 30 9 3 51 98 149 0.342
Unmarked 0 0 0 11 244 4550 4801 2498 751 12,855
Inspected 0 0 0 11 245 4558 4831 2507 754 12,906
Mark rate 0.000 0.004 0.002 0.006 0.004 0.004 0.004
Notes:
Bold numbers were used in contingency table tests (Chi-square) to evaluate whether mark and recapture rates varied by week. Adjacent shaded cells were pooled.
Period of Marking
(Statistical Week)
Period of Recapture (Statistical Week)
a 51 of the 201 radio-tagged chum salmon released at the Middle River fishwheels were never detected at or above the Middle River Gateway fixed station; and these fish were censored
from the marked sample.
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Table H-5. Recapture matrix for pink salmon radio-tagged at the Middle River fishwheels and inspected for tags at the Indian River weir, 2013.
Not Recapture
26 27 28 29 30 31 32 33 34 Recaptured Recaptured Marked a Rate
25 0 0 0
26 0 0 0
27 0 0 0
28 0 2 2 0.000
29 1 1 2 3 0.333
30 13 9 22 52 74 0.297
31 6 3 1 10 47 57 0.175
32 2 2 9 11 0.182
33 0 4 4 0.000
34 0 0 0
Marked 0 0 0 0 0 0 20 14 1 35 116 151 0.232
Unmarked 0 0 0 1 67 5124 21667 8390 1897 37,146
Inspected 0 0 0 1 67 5124 21687 8404 1898 37,181
Mark rate 0.000 0.000 0.000 0.001 0.002 0.001 0.001
Notes:
Bold numbers were used in contingency table tests (Chi-square) to evaluate whether mark and recapture rates varied by week. Adjacent shaded cells were pooled.
Period of Marking
(Statistical Week)
Period of Recapture (Statistical Week)
a 49 of the 200 radio-tagged pink salmon released at the Middle River fishwheels were never detected at or above the Middle River Gateway fixed station; and these fish were censored
from the marked sample.
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PART A - APPENDIX I: ABUNDANCE ESTIMATES FOR CHINOOK
SALMON IN THE SUSITNA RIVER DRAINAGE AND COHO SALMON
ABOVE THE YENTNA RIVER
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1. INTRODUCTION
Additional data analyses were required to estimate the Chinook salmon escapement to the entire
Susitna River and the coho salmon escapement in the Susitna River above the Yentna River
confluence, leading to the Results and Discussion for these objectives being presented separately
in this appendix.
1.1. Study Objective
From ISR 9.7, 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
See ISR 9.7, Section 3.
3. METHODS
See ISR 9.7, Section 4.8.
4. RESULTS
4.1. Estimated Abundance
4.1.1. Chinook Salmon
A total of 2,049 Chinook salmon were captured in drift gillnets and two fishwheels at the lower
mainstem Susitna River tagging site (PRM 34) from June 4 to August 15, 2013. Radio tags were
deployed on 699 Chinook salmon measuring 50 cm METF or greater. Based on observations
made at fixed tracking stations and using aerial radio-telemetry, 568 of these radio-tagged fish
moved upstream and remained upstream of the tagging site, comprising the first event in the
mark-recapture experiment. The remaining 131 radio-tagged Chinook salmon were not used in
the experiment, as they migrated to the Yentna River drainage or the Susitna River below
PRM 34, were taken by anglers prior to spawning, possibly regurgitated the radio tag, possibly
failed to migrate due to handling stress, or while unlikely, were above the tagging site and not
detected.
Second event sampling was conducted at weirs on Deshka River and Montana Creek. A total of
18,531 Chinook salmon were counted through the Deshka River weir from June 9 to September
2, 2013, with 18,003 of these fish estimated to be 50 cm METF or greater. At the Montana
Creek weir, 2,015 Chinook salmon were counted from July 8 to August 27, of which 1,949 were
estimated to be 50 cm METF or greater. Second event sampling was also conducted at a site on
the Chulitna River using ARIS sonar. However, estimates of Chinook salmon passage and
length composition from the sonar data were not available as of this ISR, so these data were not
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used to compute the estimates. The estimated numbers of Chinook salmon measuring 50 cm
METF or greater that passed the Deshka River and Montana Creek weirs comprise the second
event of the mark-recapture experiment.
Based on observations made at fixed tracking stations and using aerial radio-telemetry, 148
radio-tagged Chinook salmon passed the Deshka River weir and were assumed to have spawned
above the weir. Similarly, 11 radio-tagged Chinook salmon passed the Montana Creek weir and
were assumed to have spawned above the weir. These 159 fish comprise the recaptured fish for
the mark-recapture experiment.
Tests for size biased sampling were conducted using the KS two-sample test (Cleary et al. 2013;
Appendix A). The test for the second sampling event provided significant evidence of size
biased sampling (p < 0.001; Figure I-1). The test for 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 first event using data from fish passing the Montana Creek weir provided
no evidence of size biased sampling (p = 0.663; Figure I-3). Based on these test results, the data
were stratified into three size strata: 50.0–65.9 cm METF, 66.0–77.4 cm METF, and 77.5 cm
METF or greater. Length data were not available for eight radio-tagged fish caught with gillnet
gear in the first event sample, one each of which was recaptured at the Montana Creek and
Deshka River weir sites. These fish were allocated among the three size strata based on the size
distribution of the 84 known length fish captured in gillnets in the first event sample.
Tests for temporal and/or spatial variation in probability of capture were conducted within each
of the three size strata (Cleary et al. 2013). Tests for variation in probability of capture during
the first event 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.
For the 50.0–65.9 cm METF stratum, significant variation in probability of capture was detected
for the second sampling event on a spatial scale (p = 0.003; Table I-1a) but not on a temporal
scale (p = 0.548; Table I-1b). No significant variation in probability of capture was detected for
the first sampling event on either a spatial scale (p = 0.887; Table I-1c) or a temporal scale (p =
0.907, p = 0.347; Tables I-1e,f, respectively). These results indicate that the Chapman (1951)
model is appropriate for estimating abundance for the 50.0–65.9 cm METF stratum.
For the 66.0–77.4 cm METF stratum, significant variation in probability of capture was detected
for the second sampling event on a spatial scale (p = 0.023; Table I-2a) but not on a temporal
scale (p = 0.786; Table I-2b). Significant variation in probability of capture was detected for the
first sampling event on a spatial scale (p = 0.011; Table I-2c) but not on a temporal scale (p =
0.127; Table I-2d). However, given the differences in run timing of fish past the Deshka River
vs Montana Creek weirs, significant results from the test reported in Table I-2c (and Tables I-1c
and I-3c) may well indicate temporal variation instead of or in addition to spatial variation in
probability of capture during the marking event. These results indicate that the partially
stratified model described by Darroch (1961) is necessary for estimating abundance for the 660–
774 mm METF stratum. Attempts to fit a Darroch-type model that reflected the variation in
probability of capture detected during both sampling events were unsuccessful. As a result, an
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estimate of abundance based on the Chapman (1951) model is reported and these results are
assumed to be biased to an unknown degree.
For the 77.5 cm METF or greater stratum, no significant variation in probability of capture was
detected for the second sampling event on a spatial scale (p = 0.068; Table I-3a) or on a temporal
scale (p = 0.596; Table I-3b). No significant variation in probability of capture was detected for
the first sampling event on either a spatial scale (p = 0.347; Table I-3c) or a temporal scale (p =
0.202, p = 0.947; Tables I-3d, e). These results indicate that the Chapman (1951) model is
appropriate for estimating abundance for the 77.5 cm METF or greater stratum.
Abundance for each stratum was estimated using the Chapman (1951) model with variances
estimated using a bootstrapping approach (Efron and Tibshirani 1993), adapting the methods
described by Buckland and Garthwaite (1991) to this experimental design. Within each size
stratum, the probability that a marked fish was recaptured was modeled as a binomial process
with observed numbers of fish marked and recaptured as model parameters. For each of the two
weir sites, the numbers of fish per strata 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. The allocation of the eight fish of unknown length
among size strata was modeled as a multinomial process with total number of known length fish
caught with gillnet and the size distribution of these fish used to define model parameters. One
million bootstrap samples were generated. Confidence intervals reported are percentiles of the
bootstrap distributions of estimated parameters (Table I-4).
The abundance of Chinook salmon measuring 50 cm METF or greater spawning in the Susitna
River above the Lower River mainstem tagging site in 2013 is estimated to be 89,463 (SE =
9,523).
4.1.2. Coho Salmon
A total of 3,278 coho salmon were captured in two fishwheels at the lower mainstem Susitna
River tagging site from June 4 to August 15, 2013. Radio tags were deployed on 596 coho
salmon measuring 40 cm METF or greater. Based on observations made at fixed tracking
stations and using aerial radio-telemetry, 411 of these radio-tagged fish moved upstream and
remained upstream of the tagging site, comprising the first event in the mark-recapture
experiment. The remaining 185 radio-tagged coho salmon were not used in the experiment, as
they migrated to the Yentna River drainage or the Susitna River below PRM 34, were taken by
anglers prior to spawning, possibly regurgitated the radio tag, possibly failed to migrate due to
handling stress, or while unlikely, were above the tagging site and not detected.
Second event sampling was conducted at weirs on Deshka River and Montana Creek. A total of
22,141 coho salmon were passed through the Deshka River weir from July 10 to September 3,
2013, with all of these fish estimated to be 40 cm METF or greater. At the Montana Creek weir,
765 coho salmon were counted from July 31 to August 20 and August 26 to September 3, all of
which were estimated to be 40 cm METF or greater. The Montana Creek weir was under water
and no counting was conducted from August 21 to late on August 26. The estimated numbers of
coho salmon 40 cm METF or greater passing the Deshka River and Montana Creek weirs
comprise the second event of this mark-recapture experiment.
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Based on observations made at fixed tracking stations and using aerial radio-telemetry, 67 radio-
tagged coho salmon passed the Deshka River weir when the weir was operational and were
assumed to have spawned above that site. Similarly seven radio-tagged coho salmon passed the
Montana Creek weir when the weir was operational and spawned above that site. These 74 fish
comprise the recaptured fish for the mark-recapture experiment.
Tests for size biased sampling were conducted using the Kolmogorov-Smirnov (KS) two-sample
test (Cleary et al. 2013). The test for the second sampling event provided no evidence of size
biased sampling (p = 0.754; Figure I-4). The test for the first event using data from fish passing
the Deshka River weir provided significant evidence of size biased sampling (p < 0.001; Figure
I-5). A similar test for first event using data from fish passing the Montana Creek weir also
provided significant evidence of size biased sampling (p = 0.005; Figure I-6). These test results
indicate that no stratification by size is necessary to provide an overall estimate of abundance.
However, due to the size biased sampling detected during the marking event it was necessary to
stratify these data in order to provide the necessary weights for radio-tagged fish to provide
unbiased estimates of spawning distribution. Therefore, the data were stratified into three size
strata: 40.0–47.9 cm METF, 48.0–53.4 cm METF, and 53.5 cm METF or greater.
Tests for temporal and/or spatial variation in probability of capture were conducted within each
of the three size strata (Cleary et al. 2013). Tests for variation in probability of capture during
the first event 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.
For the 40.0–47.9 cm METF stratum, no significant variation in probability of capture was
detected for the second sampling event on a spatial scale (p = 0.607; Table I-6a) or on a temporal
scale (p = 0.757; Table I-6b). Significant variation in probability of capture was detected for the
first sampling event on a spatial scale (p = 0.002; Table I-6c) but not on a temporal scale (p =
0.151, p = 0.273; Table I-6e, f, respectively). However, given the differences in run timing of
fish past the Deshka River vs Montana Creek weirs, significant results from the test reported in
Table I-6c (and Tables I-7c and I-8c) may well indicate temporal variation instead of or in
addition spatial variation in probability of capture during the marking event. These results
indicate that the Chapman (1951) model is appropriate for estimating abundance for the 40.0–
47.9 cm METF stratum.
For the 48.0–53.4 cm METF stratum, significant variation in probability of capture was detected
for the second sampling event on a spatial scale (p = 0.005; Table I-7a) but not on a temporal
scale (p = 0.215; Table I-7b). No significant variation in probability of capture was detected for
the first sampling event on a spatial scale (p = 0.167; Table I-7c) or on a temporal scale (p =
0.785; Table I-7d). These results indicate that the Chapman (1951) model is appropriate for
estimating abundance for the 48.0–53.4 cm METF stratum.
For the 53.5 cm METF or greater stratum, no significant variation in probability of capture was
detected for the second sampling event on either a spatial scale (p = 0.341; Table I-8a) or on a
temporal scale (p = 0.296; Table I-8b). No significant variation in probability of capture was
detected for the first sampling event on a spatial scale (p = 0.476; Table I-8c) or on a temporal
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scale (p = 0.081; Table I-8e). These results indicate that the Chapman (1951) model is
appropriate for estimating abundance for the 53.5 cm METF or greater stratum.
Abundance for each stratum was estimated using the Chapman (1951) model with variances
estimated using a bootstrapping approach (Efron and Tibshirani 1993), adapting the methods
described by Buckland and Garthwaite (1991) to this experimental design. Within each size
stratum, the probability that a marked fish was recaptured was modeled as a binomial process
with observed numbers of fish marked and recaptured as model parameters. For each of the two
weir sites, the numbers of fish per strata 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. One million bootstrap samples were generated.
Confidence intervals reported are percentiles of the bootstrap distributions of estimated
parameters (Table I-9).
The abundance of coho salmon measuring 40 cm METF or greater spawning in the Susitna River
above the mainstem tagging site in 2013 is estimated to be 130,026 (SE = 24,342).
4.2. Estimated Distribution of Spawning Salmon
4.2.1. Chinook Salmon
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-4). Numbers of fish were then summed over size strata for each tributary (Table I-5).
4.2.2. 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).
4.2.3. Pink Salmon
See ISR 9.7, Section 5.2.2.3.
5. DISCUSSION
The objective to estimate the system-wide Chinook salmon escapement was not fully met, as no
estimate could be produced for the Yentna River, due to the lack of any sampling at Lake Creek
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and sonar operated at only one site, the Talachulitna River, as described in ISR 9.7, Section
4.8.1. An estimate for the Susitna River above the Yentna River was generated, although with
some unknown bias. However, the bias is restricted to one size class, 66.0–77.4 cm METF,
which is likely only about 11 percent of the escapement (9,482/89,463). The objective to
estimate the coho salmon escapement for the Susitna River above the Yentna River was
successful, as variations in probability of capture could be compensated for. The objective to
estimate the distribution of the Chinook and coho escapements among the tributaries of the
Susitna River above the Yentna River was successful, as knowledge of the marked fraction for
each size stratum allowed adjusting for unequal marked rates to reduce bias.
6. CONCLUSIONS AND RECOMMENDATIONS
To meet the objective to estimate the system-wide Chinook salmon escapement, sampling
methods other than weir or sonar on Yentna River tributaries should be attempted, such as an
additional fishwheel and gillnet site on the mainstem Yentna River. Tagging different size strata
of Chinook salmon at different rates should be investigated as a way to reduce size bias.
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Table I-1. Tests for temporal and spatial variation in probability of capture for mainstem Susitna River
Chinook salmon 50.0–65.9 cm METF, 2013.
Event Tested Parameter
a) Second eventa
Gear Gillnet Fishwheel 1 west
Fishwheel 2 east
Marks 35 127 102
Recaptured 1 25 7
Not recaptured 34 102 95
b) Second eventb
Julian day 155-160 161-164
165-180
Marks 77 98 88
Recaptured 7 14 12
Not recaptured 70 84 76
c) First eventc
Weir site Deshka R Montana Cr
Inspectedd 5,012 1,045
Marked 27 6
Unmarked 4,985 1,039
d) First evente
Deshka weir Julian day 160-174 175-177
178-182 183-247
Inspectedd 1,876 1,311 919 905
Marked 8 8 5 5
Unmarked 1,868 1,303 914 900
e) First eventf
Montana weir Julian day 169-193 194-197
198-258
Inspectedd 360 397 563
Marked 3 2 1
Unmarked 357 395 562
a Test of equal probability of capture during second event sampling: χ2 = 11.933, P = 0.003.
b Test of equal probability of capture during second event sampling: χ2 = 1.203, P = 0.548.
c Test of equal probability of capture during second event sampling: χ2 = 0.020, P = 0.887.
d Number of fish inspected for marks is estimated.
e Test of equal probability of capture during second event sampling: χ2 = 0.554, P = 0.907.
f Test of equal probability of capture during second event sampling: χ2 = 2.117, P = 0.347.
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Table I-2. Tests for temporal and spatial variation in probability of capture for mainstem Susitna River
Chinook salmon 66.0–77.4 cm METF, 2013.
Event Tested Parameter
a) Second eventa
Gear Gillnet Fishwheel 1 west
Fishwheel 2 east
Marks 16 105 41
Recaptured 5 66 19
Not recaptured 11 39 22
b) Second eventb
Julian day 155-160 161-164
165-180
Marks 51 63 74
Recaptured 30 34 39
Not recaptured 21 29 35
c) First eventc
Weir site Deshka R Montana Cr
Inspectedd 4,814 451
Marked 89 1
Unmarked 4,725 451
d) First evente
Deshka weir Julian day 160-173 174-176
177-182 183-247
Inspectedd 1,131 1,590 1.224 869
Marked 24 19 26 20
Unmarked 1,107 1,571 1.198 849
a Test of equal probability of capture during second event sampling: χ2 = 7.505, P = 0.023.
b Test of equal probability of capture during second event sampling: χ2 = 0.482, P = 0.786.
c Test of equal probability of capture during second event sampling: χ2 = 6.516, P = 0.011.
d Number of fish inspected for marks is estimated.
e Test of equal probability of capture during second event sampling: χ2 = 5.704, P = 0.127.
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Table I-3. Tests for temporal and spatial variation in probability of capture for mainstem Susitna River
Chinook salmon measuring 77.5 cm METF or greater, 2013.
Event Tested Parameter
a) Second eventa
Gear Gillnet Fishwheel 1 west
Fishwheel 2 east
Marks 33 72 29
Recaptured 6 24 4
Not recaptured 27 48 25
b) Second eventb
Julian day 155-160 161-164
165-180
Marks 53 49 32
Recaptured 14 14 6
Not recaptured 39 35 26
c) First eventc
Weir site Deshka R Montana Cr
Inspectedd 8,177 452
Marked 31 3
Unmarked 8,146 459
d) First evente
Deshka weir Julian day 160-173 174-176
177-182 183-247
Inspectedd 1,922 2,700 2,079 1,477
Marked 4 8 10 9
Unmarked 1,918 2,692 2,069 1,468
e) First eventf
Montana weir Julian day 169-193 194-197
198-258
Inspectedd 64 70 99
Marked 1 1 1
Unmarked 63 69 98
a Test of equal probability of capture during second event sampling: χ2 = 5.364, P = 0.068.
b Test of equal probability of capture during second event sampling: χ2 = 1.036, P = 0.596.
c Test of equal probability of capture during second event sampling: χ2 = 0.884, P = 0.347.
d Number of fish inspected for marks is estimated.
e Test of equal probability of capture during second event sampling: χ2 = 4.623, P = 0.202.
f Test of equal probability of capture during second event sampling: χ2 = 0.109, P = 0.947.
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Table I-4. 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, 2013.
Size Strata Estimated Abundance Estimated SE Radio Tags Deployeda Relative Weight spawners/tag
50.0-65.9 cm METF 46,667 7,981 263 175.2
66.0-77.4 cm METF 9,482 711 161 58.3
≥77.5 cm METF 33,315 5,239 134 242.9
a Does not include two radio-tagged fish for which final spawning locations were not determined.
Table I-5. Chinook salmon spawning distributions, based on weighted abundance (Table I-4), in the
mainstem Susitna River above the lower river tagging site, 2013.
Estimated
Abundance
Intervals
Location SE 95% lower 95% upper
Susitna River above the mainstem tagging site 89,463 9.523 77,720 114,954
PRM 34–102.4 mainstem Susitna River a 2,432 259 2,112 3,124
Deshka River 18,469 1,573 16,643 22,801
Eastside Susitna River 16,867 1,873 14,541 21,860
Talkeetna River 24,408 3,008 20,619 32,362
PRM 102.4–153.4 mainstem Susitna River b 7,680 898 6,560 10,066
Chulitna River 19,607 2,161 16,907 25,352
a PRM 34 upstream to the Chulitna River Confluence
b Chulitna River Confluence to Devils Canyon
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Table I-6. Tests for temporal and spatial variation in probability of capture for mainstem Susitna River coho
salmon 40.0–47.9 cm METF, 2013.
Event Tested Parameter
a) Second eventa
Gear Fishwheel 1 west Fishwheel 2 east
Marks 79 75
Recaptured 14 11
Not recaptured 65 64
b) Second eventb
Julian day 190-203 204-207
208-232
Marks 62 40 52
Recaptured 11 5 9
Not recaptured 51 35 43
c) First eventc
Weir site Deshka R Montana Cr
Inspectedd 912 37
Marked 21 4
Unmarked 891 33
d) First evente
Deshka weir Julian day 190-223 224
225-228 229-246
Inspectedd 100 334 157 322
Marked 3 4 7 7
Unmarked 97 330 150 315
e) First eventf
Montana weir Julian day 190-231 232-246
Inspectedd 10 27
Marked 2 2
Unmarked 8 25
a Test of equal probability of capture during second event sampling: χ2 = 0.264, P = 0.607.
b Test of equal probability of capture during second event sampling: χ2 = 0.558, P = 0.757.
c Test of equal probability of capture during second event sampling: χ2 = 10.035, P = 0002.
d Number of fish inspected for marks is estimated.
e Test of equal probability of capture during second event sampling: χ2 = 5.302, P = 0.151.
f Test of equal probability of capture during second event sampling: χ2 = 1.200, P = 0.273.
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Table I-7. Tests for temporal and spatial variation in probability of capture for mainstem Susitna River coho
salmon 48.0–53.4 cm METF, 2013.
Event Tested Parameter
a) Second eventa
Gear Fishwheel 1 west Fishwheel 2 east
Marks 74 74
Recaptured 23 9
Not recaptured 51 65
b) Second eventb
Julian day 190-207 208-211
212-232
Marks 80 24 44
Recaptured 20 2 10
Not recaptured 60 22 34
c) First eventc
Weir site Deshka R Montana Cr
Inspectedd 5,888 270
Marked 29 3
Unmarked 5,859 267
d) First evente
Deshka weir Julian day 190-223 224
225-233 234-246
Inspectedd 643 2,159 1.908 1,178
Marked 2 12 8 7
Unmarked 641 2,147 1.900 1.171
a Test of equal probability of capture during second event sampling: χ2 = 7.815, P = 0.005.
b Test of equal probability of capture during second event sampling: χ2 = 3.071, P = 0.215.
c Test of equal probability of capture during second event sampling: χ2 = 1.911, P = 0.167.
d Number of fish inspected for marks is estimated.
e Test of equal probability of capture during second event sampling: χ2 = 1.066, P = 0.785.
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Table I-8. Tests for temporal and spatial variation in probability of capture for mainstem Susitna River coho
salmon measuring 53.5 cm METF or greater, 2013.
Event Tested Parameter
a) Second eventa
Gear Fishwheel 1 west Fishwheel 2 east
Marks 59 50
Recaptured 11 6
Not recaptured 48 44
b) Second eventb
Julian day 190-208 209-212
213-232
Marks 54 18 37
Recaptured 11 1 5
Not recaptured 43 17 32
c) First eventc
Weir site Deshka R Montana Cr
Inspectedd 15,341 458
Marked 17 0
Unmarked 15,324 458
d) First evente
Deshka weir Julian day 190-224 225-233
234-246
Inspectedd 7,300 4,971 3,070
Marked 5 5 7
Unmarked 7,295 4,966 3,063
a Test of equal probability of capture during second event sampling: χ2 = 0.908, P = 0.341.
b Test of equal probability of capture during second event sampling: χ2 = 2.435, P = 0.296.
c Test of equal probability of capture during second event sampling: χ2 = 0.508, P = 0.476.
d Number of fish inspected for marks is estimated.
e Test of equal probability of capture during second event sampling: χ2 = 5.038, P = 0.081.
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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, 2013.
Size Strata
Estimated
Abundance Estimated SE
Radio Tags
Deployeda
Relative Weight
spawners/tag
40.0-47.9 cm METF 5,666 1,129 154 36.8
48.0-53.4 cm METF 27,805 4,585 147 189.1
≥53.5 cm METF 96,556 23.880 109 885.8
a Does not include 1 radio-tagged fish for which final spawning location was not determined.
Table I-10. Coho salmon spawning distributions, based on weighted abundance (Table I-9), in the mainstem
Susitna River above the lower river tagging site, 2013.
Estimated
Abundance
Intervals
Location SE 95% lower 95% upper
Susitna River above the mainstem tagging site 130,026 24,342 100,411 193,403
PRM 34–102.4 mainstem Susitna Rivera 31,204 6,604 23,224 48,365
Deshka River 29,215 5,386 22,629 43,231
Eastside Susitna River 11,038 1,837 8,764 15,839
Talkeetna River 13,372 2,277 10,568 19,324
PRM 102.4–153.4 mainstem Susitna Riverb 8,313 1,566 6,402 12,383
Chulitna River 36,844 6,726 28,684 54,413
a PRM 34 upstream to the Chulitna River Confluence
bChulitna River Confluence to Devils Canyon
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Figure I-1. Empirical cumulative distribution functions (ECDF) of length (in mm) of all Chinook salmon
marked during first event sampling at the lower mainstem Susitna River tagging site and all recaptures
during second event sampling, 2013.
Note: The Kolmogorov-Smirnov test results for equal probability of capture based on METF length
during second event sampling were D = 0.272, P < 0.001.
0.00
0.25
0.50
0.75
1.00
500 600 700 800 900 1000 1100Cumulative Relative Frequency Length METF - D = 0.272, p < 0.001
ECDF - Marks vs. Recaptures
Marks (560)
Recaptures (157)
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Figure I-2. Empirical cumulative distribution functions (ECDF) of length (in mm) of Chinook salmon
inspected for marks and all recaptured salmon during second event sampling at the Deshka River weir, 2013.
Note: The Kolmogorov-Smirnov test results for equal probability of capture based on METF length
during first event sampling were D = 0.243, P < 0.001.
0.00
0.25
0.50
0.75
1.00
500 600 700 800 900 1000 1100Cumulative Relative Frequency Length METF - D = 0.243, p < 0.001
ECDF - Deshka Captures vs. Recaptures
Captures (273)
Recaptures (147)
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Figure I-3. Empirical cumulative distribution functions (ECDF) of length (in mm) of Chinook salmon
inspected for marks and all recaptured salmon during second event sampling at the Montana Creek weir,
2013.
Note: The Kolmogorov-Smirnov test results for equal probability of capture based on METF length
during first event sampling were D = 0.233, P = 0.663.
0.00
0.25
0.50
0.75
1.00
500 600 700 800 900 1000 1100Cumulative Relative Frequency Length METF - D = 0.233, p = 0.663
ECDF - Montana Captures vs. Recaptures
Captures (207)
Recaptures (10)
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Figure I-4. Empirical cumulative distribution functions (ECDF) of length (in mm) of all coho salmon
marked during first event sampling at the lower mainstem Susitna River tagging site and all recaptures
during second event sampling, 2013.
Note: The Kolmogorov-Smirnov test results for equal probability of capture based on METF length
during second event sampling were D = 0079, P = 0.754.
0.00
0.25
0.50
0.75
1.00
400 450 500 550 600 650Cumulative Relative Frequency Length METF - D = 0.079, p = 0.754
ECDF - Marks vs. Recaptures
Marks (596)
Recaptures (74)
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Figure I-5. Empirical cumulative distribution functions (ECDF) of length (in mm) of coho salmon inspected
for marks and all recaptured salmon during second event sampling at the Deshka River weir, 2013.
Note: The Kolmogorov-Smirnov test results for equal probability of capture based on METF length
during first event sampling were D = 0.439, P < 0.001.
0.00
0.25
0.50
0.75
1.00
400 450 500 550 600 650Cumulative Relative Frequency Length METF - D = 0.439, p < 0.001
ECDF - Deshka Captures vs. Recaptures
Captures (267)
Recaptures (67)
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Figure I-6. Empirical cumulative distribution functions (ECDF) of length (in mm) of coho salmon inspected
for marks and all recaptured salmon during second event sampling at the Montana Creek weir, 2013.
Note: The Kolmogorov-Smirnov test results for equal probability of capture based on METF length
during first event sampling were D = 0.657, P = 0.005.
0.00
0.25
0.50
0.75
1.00
400 450 500 550 600 650Cumulative Relative Frequency Length METF - D = 0.657, p = 0.005
ECDF - Montana Captures vs. Recaptures
Captures (200)
Recaptures (7)