HomeMy WebLinkAboutAPA2743SUSITNA
HYDROELECTRIC PROJECT
FEDERAL ENERGY REGULATORY COMMI8SION
PROJECT No.7114
STREAM FLOW RELATIONSHIPS REPORT SERIES
FISH RESOURCES AND HABITATS
IN THE MIDDLE SUSITNA RIVER
TECHNICAL REPORT No.1
ODWARD-CLYDE CONSULTANTS
FINAL REPORT
APRIL 1985
DOCUMENT No.2744
~~ALASKA POWER AUTHORITY..___----....
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SUSITNA HYDROELECTRIC PROJECT
Document No.2744
Susitna rile No.4.3.1.4
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INSTREAM FLOW RELATIONSHIPS REPORT SERIES
FISH RESOURCES AND HABITATS IN THE
MIDDLE SOSITNA RIVER
TECHNICAL REPORT NO.1
Prepared by
Woodward-Clyde Consultants
Entrix
Under Contract To
Harza-Ebasco Susitna Joint Venture
Prepared for
Alaska Power Authority
Final Report
April 1985
ARLIS
Alaska Resources
Library &Infonm.lti{)tl ServIces
Anchorage,Alask~l
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The primary author of this report is T.R.Jennings.The draft version of
this report was prepared while he was an employee of Woodward-Clyde
Consultants.The final version was prepared while an employee of Entrix,
Inc.,under contract to Woodward-Clyde Consultants.
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This report represents a volume of the Instream Flow
Relationships study·technical report series prepared for the
Susitna Hydroelectric Project.The primary purpose of the
Instream Flow Relationships Report and its associated technical
report series is to present technical information and data that
reflect the relative importance of the various interactions
among the primary physical and biolog:ical components of aquatic
habitats within the Talkeetna-to-Devil Canyon reach of the
Susitna River.The Instream Flow Relationships Report and its
associated technical report series are not intended to be an
impact assessment.However,these reports present a variety of
natural and with-project relationships tha~provide a
quantitative basis to compare alternative streamf~ow regimes,
conduct impact analyses,and prepare mitigation plans.
The technical report series is based on the data and findings
presented in a variety of baseline data reports p~epared by the
Alaska Department of Fish and Game (ADF&G)SU Hydro Aquatic
study Team,R&M Consultants,E.Woody Trihey and Associates
(EWT&A)and the Arctic Environmental Information and Data
Center (AEIDC).The Instream Flow Relationships Report and its
associated technical report series provide the methodology and
appropriate technical information for use by those deciding how
best to operate the proposed Susitna Hydroelectric Project for
the benefit of both power production and downstream fish
resources.The technical report series is described below.
Tec:hnical Report No.1.Fish Resources and Habitats in the
Middle Susitna River.This report,prepared by Entrix,In~.
and Woodward-clyde Consultants,consolidates information on the
fish resources and habitats in the Talkeetna-to-Devil Canyon
reach of the Susitna River available through January 1985 that
is currently dispersed throughout numerous reports.
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Technical Report No.2.Physical Processes Report.This
report,being prepared by Harza-Ebasco and R&M Consultants,
describes such physical processes as:reservoir sedimentation,
channel stability and groundwater upwelling.
Technigal Report No.3.Water Quality/Limnology Report.This
report,being prepared by Harza-Ebasoo,consolidates existing
information on water quality in the Susitna Basin and provides
technical discussions of the potential for with-project
bioaccumulation of mercury,influences on nitrogen gas
sup1arsaturation,changes in downstream nutrients,and changes
in turbidity and suspended sediments.A draft report based
pri:ncipally on data and information that were available through
Junia 1984 was prepared in November 1984.
Tech.nical Report No.4.Instream Temperature.This report,
prepared by AEIOC,consists of three principal components:(1)
ins'cream temperature modeling:(2)development of temperature
cri'ceria for Susitna River fish stocks by species and life,
stal;Je:and (3)evaluation of the influences of with-project
stream temperatures on existing fish habitats and natural ice
processes.A final report describing downstream temperatures
asslociated with various reservoir operating scenarios and an
evaluation of these stream temperatures on fish was prepared in
Octlober 1984.A draft report addressing the influence of
anticipated with-project stream temperatures on natural ice
proc::esses was prepared in November 1984.
Tecbnical Report No.5.Aquatic Habitat Report.This report,
being prepared by EWT&A,describes the availability of various
types of aquatic habitat in the TalkE"etna-to-Oevil Canyon river
reac::h as a function of mainstem discharge.A preliminary draft
of 'this report is scheduled for March 1985 with a draft final
repc:lrt prepared in FY86.
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Technical Report No.6.Ice Processes Report.This report
being prepared by AEIDC,Harza-Ebasco,and R&M Consultants will
describe naturally occurring ice processes in the middle river,
anticipated changes in those processes due to proj ect
construction and operation,and discuss the ~ffects of
nat'urally occurring and with-project ice conditions on fish
habitat.
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TABLE OF CONTENTS
PRE:~ACE iii
LIS~!'OF FIGURES viii
..-LIS~!'OF TABLES xi
1.0 INTRODUCTION •1
2.0 BACKGROUND •3
9
9
9
12
15
15
20
20
23
23
30
30
30
30
31
31
31
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OVERVIEW OF IMPORTANT SPECIES
CONTRIBUTION TO COMMERCIAL FISHERY
3.2.1 Sockeye Salmon.
3.2.2 Chum Salmon
3.2.3 Coho Salmon
3.2.4 Pink Salmon
3.2.5 Chinook Salmon.
SPORT FISHING •
3.3.1 Arctic Graylinq
3.3.2 Rainbow Trout
3.3.3 Pink Salmon
3.3.4 Coho Salmon •'.
3.3.5 Chinook Salmon.
3.3.6 Chum Salmon
3.3.7 Sockeye Salmon ..
SUBSISTENCE FISHING •3.4
3.3
INTRODUCTION TO FISH RESOURCES
3.1
3.2
3.0
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4.0 SPECIES BIOLOGY
4•1 ADULT SALMON
4.1.1 Sockeye Salmon.
4.1.2 Chum Salmon
4.1.3 Coho Salmon
4.1.4 Pink Salmon
4.1.5 Chinook Salmon.
4 •2 INCUBATION
4.2.1 Dissolved Oxyqen •
4.2.2 Temperature
4.2.3 Substrate
4.2.4 Streamflow.
4.2.5 superimposition
4.2.6 Predators
4.3 JUVENILE SALMON.
4.3.1 Sockeye Salmon.
4.3.2 Chum Salmon
4.3.3 Coho Salmon
4.3.4 Pink Salmon
4.3.5 Chinook Salmon.
4.4 RESIDENT SPECIES
4.4.1 Rainbow Trout •
32
32
32
43
57
63
72
82
84
86
90
91
92
93
93
93
99
104
109
113
118
118
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TABLE OF CONTENTS (continued)
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4.4.2 Arctic Grayling · ·
•••• •···• •
4.4.3 Burbot .··•· · ·
•· · · ····4.5 OTHER SPECIES .·· · · · · · · ··•·•···4.5.1 Round Whitefish ···· · ·
•·· ·4.5.2 Long-nose Sucker · ··· ···•····4.5.3 Humpback Whitefish · ·
•··•·4.5.4 Dolly Varden · · ···•· · · ·
•·4.5.5 Arctic Lamprey · · · · · ····-4.5.6 Threespine stickleback ··· ···•··4.5.7 Bering cisco ·••····•· · · ·4 ..5.8 Eulachon ····•· ·
•··· ·
•···4.5.9 Sculpin · ·
•· ··•·····4.5.10 Lake Trout · ·
•·•· · · · · · · ·4.5.11 Northern pike •····· ······ ·4.5.12 Ninespine Stickleback · · · · · ·
·•·
119
120
121
121
122
123
123
123
124
124
124
125
125
125
126
5.0 SUMMARY OF HABITAT UTILIZATION.• • • • • • • •••127
5.1 MAINSTEM AND SIDE CHANNEL HABITATS • •••127
5 ..1.1 Adult Salmon.• • • • • • • • •••127
5.1.2 Juvenile Salmon • • • • • • • • • •••129
5 ..1.3 Resident species.• • • • • • • • •130
5.2 SIDE SLOUGH AND UPLAND SLOUGH HABITATS • •••131
5.2.1 Adult Salmon.• • • • • • • • • • •••132
5 ..2 •2 Juvenile Salmon • • • • • • • • • •••133
5.2.3 Resident Species.• • • • • • • • •••134
5.3 TRIBUTARY AND TRIBUTARY MOUTH HABITATS ••135
5.3.1 Adult Salmon.• • • • • • • • • • •••135
5.3.2 Juvenile Salmon • • • • • • • • • •136
5.3.3 Resident Species.• • • • • • • • •••137
ADF&G SUSITNA HYDRO REFERENCE LIST
IN CHkONOLOGlCAL ORDER • • • • • •
.. . . ..... . .. .. . .....
... .... .. . . ... ... ...
APPll:NDIX A.
156
139
139
140
144
147
148
·... .
·.. .... .
· ... .. . .
......· .......FACTORS AFFECTING PRODUCTION • • • •
6•1 ADULT SALMON • • • • • • • • •
6•2 SPAWNING AND INCUBATION • • • •
6•3 REARING.• • • • • • • • • • •
6.0
ACmQOWLEDGEMENTS
LITll:RATURE CITED-
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LIST OF FIGURES
General habitat categories of the Susitna
River - a conceptual diagram.••••
I~
Figure 1.
Figure 2.
susitna River drainage basin..... ..4
5
Figure 3.Upper Cook Inlet commercial salmon management
area.• • • • • • •11
Figure 4.
Figure 5.
Commercial catch of upper Cook Inlet salmon,
1954-1983.••••••••••••••••••13
Commercial catch of upper Cook Inlet sockeye,
1954-1983.••••••••••••••••••17
Figure 6.
Figttre 7.
Commercial catch of upper Cook Inlet chum,
1954-1983 • • • • • • • • • • • • • • • • •
Commercial catch of upper Cook Inlet coho,
1954-1983 • • • • • • • • • • • • • • • • •
18
19
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Figttre 8.
Figl;lre 9.
Commercial catch of upper Cook Inlet pink,
1954-1983 • • • • • • • • • • • • • • • • • • •21
Commercial catch of upper Cook Inlet phinook,
1954-1983 • • • • • • • • • • • • • • • • • • •22
Figure 10.
Figure 11.
susitna River and major tributaries from
mouth to Sheep Creek.• • • • • • • • • •
Susitna River and major tributaries from
Sheep Creek to Devil Canyon • • • • • • •
27
28
Figure 12.Migrational timing of second-run sockeye
salmon based on fishwheel catch per unit
effort at selected locations on the Susitna
~River in 1981,1982 and 1983 • • • • • • • • • •34
Figu.re 13.Comparison of second-run sockeye fishwheel
catch and mainstem discharge at Sunshine
station (RM 80)1981-1983 ••••••••••••35
Figu.re 14.Migrational timing of c:hum salmon based on
fishwheel catch per unit effort at selected
locations on the susitna River in 1981,1982
and 1983 • • • • • • • • • • • • • • • •••45
Figu.re 15.Comparison of chum salmon fishwheel catch and
mainstem discharge at Sunshine station (RM 80),
1981-1983.• • • • •••••••••••••47
viii
Figure 16.
Fig'ure 17.
LIST OF FIGURES (continued)
Migrational timing of coho salmon based on
fishwheel catch per unit effort at selected
locations on the Susitna River in 1981,1982
and 1983 •••••••••'•••••••••••58
Comparison of coho salmon fishwheel catch
and mainstem discharge at Sunshine Station
(RM 80),1981-1983 •••••••••••••••59
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Figure 18.Migrational timing of pink salmon based on
fishwheel catch per unit effort at selected
locations on the Susitna River in 1981,1982
and 1983 • • • • • • • • • • • • • • • • • • • •65
Figure 19.Comparison of pink salmon fishwheel catch and
mainstem discharge at Sunshine Station,(RM 80),
1981-1983 ••••••••••••••••••••66
Figure 20.Migrational timing of chinook salmon based on
fishwheel catch per unit effort at selected
locations on the Susitna River in 1981,1982
and 1983 • • • • • • • • • • • • • • • • • • • •74
Figure 21.Comparison of chinook salmon fishwheel catch
and mainstem discharge at Sunshine Station,
(RM 80),1981-1983 •••••••••••••••76
Figure 22.Chum salmon spawning time versus mean
Iincubationtemperaturenomograph• • •. ...•89
Figure 23.Distribution of juvenile sockeye salmon by
macrohabitat type on the Susitna River between
the Chulitna River confluence and Devil Canyon,
May through October 1983.Percentages are
based on mean catch per cell • • • • • • • • • •95
Figure 24.Chum salmon fry daily catch per hour recorded
at the downstream migrant traps,May 18 through
August 20,1983 and sockeye salmon fry daily
catch per hour recorded at the downstream
migrant traps,May 18 through August 30,1983 ••97
Figure 25.Distribution of juvenile chum salmon by
macrohabitat type on the Susitna River between
the Chulitna River confluence and Devil Canyon,
May through October 1983.Percentages are
based on mean catch per cell ••••••••..101
Fiqure 26.Coho salmon age 0+and age 1+or older daily
catch per hour recorded at the downstream
migrant traps,May 18 through August 30,1983 .105
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LIST OF FIGURES (continued)
Fi~lre 27.Distribution of juvenile coho salmon by
macrohabitat type on the Susitna River between
the Chulitna River confluence and Devil canyon,
May through November 1983.Percentages are
based on mean catch per cell • • • • • • •••106
Figure 28.Pink salmon fry daily catch per hcnr recorded
at the downstream migrant traps,May 18 through
July 8,1983 • • • • • • • • • ••••• •111
Figure 29.Distribution of juvenile chinook salmon by
macrohabitat type on the Susitna River between
the Chulitna River confluence and Devil Canyon,
May through November 1983.Percentages are
based on mean catch per cell ••••••••••115
Figtlre 30.Chinook salmon age 0+and age 1+daily catch
per hour recorded at the downstream migrant
traps,May 18 through August 30,1983 •••••117
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Ta:ble 1.
LIST OF TABLES
Common and scientific names of fish species
observed in the Susitna Basin • • • • • • •10
Table 2.
Table 3.
Table 4.
Table 5.
Commercial catch of upper Cook Inlet Salmon
in numbers of fish by species,1954-1984 ••
Summary of commercial and sport harvests on
Susitna River basin adult salmon returns.•
Susitna Basin sport fish harvest and effort
by fishery and species -1978,1979,1980,
1981,1982 and 1983 • • • • • • • • • • • •
Sport fish harvest for Southcentral Alaska
and Susitna Basin in numbers of fish by
species,1978-1983 ••••••••••••
Average salmon escapements in the Susitna
River by species and location • • • • • •
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16
24
29
36
Second-run sockeye salmon peak survey
counts in sloughs upstream of RM 98.6,1981-
1984 ••••.•.•.••...... .39
Second-run sockeye salmon total slough
escapement upstream of RM 98.6,1981-1984 . . .40
Sex ratios of second-run sockeye at
Flathorn,Susitna,Yentna,Sunshine,
Talkeetna and curry stations,1981-
1984 • • • • • • • • . • • • • • • •. . .. ..44
Table 10.Chum salmon peak index counts by habitat
type upstream of RM 98.6,1981-1984 •••
Table 11.Chum salmon peak index counts in sloughs
11pstream of RM 98.6,1981-1984 • • • • •
. . ..49
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Table 12.Chum salmon total slough escapement upstream of
l~98.6,1981-1984 •••••••••••
Table 13.Chum salmon peak index counts in streams
upstream of RM 98.6,1981-1984 •••••
Table 14.Chum salmon peak spawner counts in mainstem
habitats upstream of RM 98.6,1981-1984 •••
xi
51
52
54
Table 15.
Table 16.
Table 1/.
Table 18.
LIST OF TABLES (continued)
Sex ratios of chum salmon at F1athorn,
Susitna,Yentna,Sunshine,Talkeetna and
Curry Stations,1981-1984 ••••••••
Coho salmon peak index counts in streams
upstream of RM 98.6,1981-1984 •••••
Sex ratios of coho salmon at Flathorn,
Susitna,Yentna,Sunshine,Talkeetna and
Curry Stations,1981-1984.• • • • • • •
Pink salmon peak index counts in streams
upstream of RM 98.6,1981-1984 •••••
·. .
·..
56
62
64
69
Table 19.Pink salmon total slough escapement upstream
of RM 98.6,1981-1984 •••••••••••••71
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Table 20.
Table 21.
Sex ratios of pink salmon at Flathorn,
Susitna,Yentna,Sunshine,Talkeetna and
Curry stations,1981-1984 ••••••••
Chinook salmon peak survey escapement
counts of Susitna River streams by sub-
basin from 1976 to 1984 •••••••••
· . .
· . .
73
77
Table 22.Chinook salmon peak index counts in
streams upstream of RM 98.6,1981-1984 ..80
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Table 23.Sex ratios of chinook salmon at Yentna,
Sunshine,Talkeetna and CUrry stations,
1981-1984 •••••••••••••••••
xii
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1.0 INTRODUCTION
This report summarizes the available information on the fishery
resources and habitats of the Susitna River,with emphasis on
the river reach between Talkeetna and Devil Canyon.It is
based primarily on existing reports and analyses generated by
the feasibility and licensing studies of the Susitna
Hydroelectric Project,with a lesser dependence on additional
pert~inent information in the literature.The objective of the
report is to synthesize and summarize information to describe
the biology,relative abundance and seasonal habitat
utilization of important fishery resources.As a part of the
Inst~ream Flow Relationships (IFR)report series,information
sUDmLarized here will assist in defining the relationships
between physical processes and fishery habitat in the Susitna
Rive~r basin.
since the report series provides important information relative
to t~he decision making process,this report focus~s on habitats
and species most likely to be affected by the proposed project.
Most~of the report emphasizes the Talkeetna-to-Devil Canyon
reach (rivet-mile (RM)98.6-152]of the Susitna River.This
rivelr reach extends from the proposed Devil Canyon dam site (RM
152)downstream to the confluence of the Susitna and Chulitna
rive:rs (RM 98.6).Effects on habitats downstream of the
proposed project are expected to be greatest within this reach_
Downstream from Talkeetna,the inflow from the Talkeetna and
Chulitna rivers is expected to reduce the magnitude of changes
in physical processes under with-project conditions.
This report emphasizes salmon and important resident species,
and their habitat utilization.section 2.0 contains a brief
description of the proj ect and proj ect area and a summary of
the studies that have been conducted to date on the fish
resources.In Section 3.0 the species of the Susitna River are
introduced a.nd their commercial,recreational and subsistence
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utilization and importance are discussed.section 4.0
SUlDIIlIarizes information on the species biology of the fish in
the Susitna River.Habitat utilization by species/life stages
is summarized in Section 5.0.section 6.0 discusses some
fact.ors that may affect fish production in freshwater and th~\~
Susitna River drainage.
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2.0 BACKGROUND
The Susitna River flows approximately 318 miles (530 km)and
drains about 19,600 square miles (50,900 km 2 )from the terminus
of the Susitna Glacier in the Alaska MOlJ"1tain Range to Cook
Inlet (Figure 1).The study area for the Susitna Hydroelectric
pro:ject includes the Susitna River mainstem,side channels,
sloughs,and tributaries.A diagram and description of habitat
categories of the Susitna River is presented in Figure 2.
The Alaska Power Authority (APA)has proposed construction of
two dams on the Susitna River:Watana Dam (RM 184)and Devil
Canyon Dam (RM 152).The project would reduce streamflows
during the summer and increase them during the winter.
Suspended sediment levels,turbidity and water temperatures are
expected to follow similar patterns (reduced levels in summer
and increased levels in winter).Details of dam construction,
opeJ::'ation a:nd expected changes to aquatic habitats and fish
res()urces were presented by Acres American (19S3a,b)in the
FedE!ral Energy Regulatory Commission (FERC)license applica-
tion.Additional studies and analyses have since taken place
that:furtheJ::'refine and update the license application.Any
questions c10ncerning the license application and studies in
support of the application should be directed to the APA.
Beginning in 1974,detailed studies were conducted to describe
and quantify fish resources,aquatic habitats and habitat
utilization in the Susitna River.In 1980 the Susitna
HydJ:"oelectri.c Proj ect Aquatic Studies Program was initiated and
funded by the APA.Baseline data collection by ADF&G Su Hydro
on fish and aquatic habitat resources was divided in.to three
groups:Adult Anadromous Fish Studies (AA),Juvenile Anadromous
and Resident Fish Studies (RJ),and Aquatic Habitat and
Ins1:ream Flow Studies (AR).
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SUSITNA RIVER DRAINAGE BASIN.
ALASKA POWER AUTHORITV
SUSITNA HYDROELECTRIC PROJECT
FIGURE 1
Woodward·Clyde Consultants
and
ENTAIX,INC.
HARZA-EBA$CO
SUSITNA JOINT VENTURE
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CE"ERAL IIABITAT CAl£r.oRIES Of l"E SUSITNA RIVER
lJ1 ,~:;::m?':;:72i;·:/
11
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".'nsU'.H,ltthl (:onshu uf tho51!'portions of lh~SUIltna RlvlPr thlt
~T1'Y~Slr.,..'IDN throughout lb.y••r.Both !lIngle .n(ll:1J'ttple
,",nllt'f r.IlIChe5 are Intluded In thl$h,blt,l (,tegory.Grounchl.tf'r .nd
lrlbul.,)'l"rIOW IpplPiIr to be Incannquent ..,contrlbutorl to th~oVl!!'rll1
chultt.rhtlu of INlnHe-1II h.bIUl.M.tnstH!h.bH.t h l,p'ClU)'
ch.r.clrrfted by 1III'9h ~'Ur vlPlocllfes and \Itt".nnored ,tl"lP.lI'tJpdl.
SubUutt's 9f'ntrally tnnsht of bouldr.r and cobble Sill!lerl.h .lth
interstithi spltU ,iiiea with.grovt-ihr ...hturlP 0'n grIVeh ,nd
9hd,I und'_S.,!opench,d Stdt~nl concentr.tloft1o ,nd lurbtdtty .re high
durln9 '.......r due-to the Innv.nn of '!I1ICI.1 .H·If.tt't".strlP"lnOlll~
n!'c.d.In uri)'f.lI .nd thlP ~Iniotetlt (;I.,n .pprlPcl,b')'In October.An
let'covn fOrMS pn th.rly"r tn "tIP Novewb.r 01'I.Jec~er.
Sldf O.nn.1 HlbUu conshU of thou portlohs of th"Susttn'IlvlPr lh.t
l'l PnN l')'cOI1.e)'IIre-lliflo.durtnfJ th.oj;ten NUn unon but ~c~
,pp,.cllb')'dt'N'lter.d durll'l'9 ~rlodl of low flow.Side-chlnnel h.Mht
IN)'tlliU "lth",In IfIPIl dltflnrd ovuflow chltlnrh.or In pood)'d"r\n'l'd
••tfl"(:Qurns flow'ng U,rot.l9"pitt lin,,ub.rged fJrlWlPl b,rs Ind hhn6s
.II)"fJ th...,gins of th.NlnHr-t rlv,r.Sldr ch,nnel Slre...ibrd rllP-
Vltlons Ire t)'plc.ll)'Tower th,n the ",n "",nthl,~Ilf'r sur"u e-I,-
VlUO"S of th.",,1nll81 Su~ttnl Rher observed 6urlng June.July ,nd
August.SldlP ch,nnlPl h,btUts Ire chlrlcurll.d by t,hll1owlPr dl'prht,.
lowr veloc'tl.s Ind s..lt.,It'tI~lPd _terl,11 th,n the .djlCent
h,bhll 0'the "'nltN rtv.r.
Side SI~H.bltllllt Is 10Cltf'd In sprln'U fed o...rf 1(*Chlnn.B bdwpn
i1ie-fiiJg.C)'----O'-irToodphln Ind the NlnU..,"d ",.ch,nneh tlf the
51,11ltn.Rh.r ,nd Is Ulullt)"uP"UlPd fr..the .,.Ittst....'lid "••
chlnneh h)'",,11 v''I"UUd b.r~.At:!e.lposed .ltuvl.1 b",.nft.ft
",pU'I.S thlP h...d nf the slOU9h frCWI NtnSle-01'ltd.thln~1 flow;.
Thlt ermtrolllnlj UrlPlIII"'.d/Uru.'''••le.,.t lon~IlIt thp upstre,.rnd of
the lide "Ioog"t,Irf!sllghtl)'11tH th,n the "'Itpr svrflCe rleutto..s of
t".N'n lIIIOnthl)"flow"of t"e N'OUetII SVltln.Ih.1'nbSf!'rwed ftlr Jvne.
Jul)'••nd August.At tnll'rwdlU.Ind 1000·flow Pf'rlodl.the slrte ,lpughs
'tOn.fI)'dIP"lII,t.r fr.u ..l1 trlbl,lt.,.es Ind/or upwltlnlJ '1roundN.tt'r
«ADfIC 19R1c.I'URlb).'h.se cllP,r \fltlr InfiOll'lre "Bot",'"Con-
trthutor;to the ••htenu of this h'blt,t t)'~.'h.""ter surhce
.I.vllton of th.SUlhn,l'vlPr tItner,ll)'(lvsn •b"."ller to nt"nd
""II bP 'nto thlP ,Iovgh frc.t tu 1000r end (ADFIG 19A1c.198~b).h"n
though this subst,nUAI b,d~lt.r uhl1.th.,t,IOU9hS fUflctlon hydr,...
Th:.ll)',.r)'..t.h lib sNIl Ure••,)',t...,,nd snerl'hundre"feet of
the "lough chlMel oft.,n I;:onv,,)',",Ur tftdep~ndtnt of ..Inst",b".~.t.r
.ff.ctl.Al high fli:*s the "U~r surhce el.utlOf'of th....lnU"rher
"sufllet.nt to ove-rtop th.upJ\*r end of the .toogh (AIlFIG .98Ic.
198i!'b).Su,hc."UIP'telllPl!rtturU I"tht stdIP sloo'UhI durtn9 s~r
IlOl'lth .."f pdnt",II)'•function of .Ir ttllllPf,.tur••tohr ,.dl,tloll•
•l'ld th.tNlPt,.tvre of the loCi I 'unoff.
~:~t~:.~1;9hort:J:'stl~~~ret,tn~~o.;n~:~:~:ctl.l:uZ~thhl~hlet."tur~~t:~h~~t~~
of the Nll1st",Sulltn.Ihlr or Itl IldlP chlnnl'lI.'heu sloughs Ire
chu.cte,I""b)'thp prp"pnt..of bener 6,.s ,nd .nlccUlJ\lhtlon of "ttl
tOvfrtng th.subst,.t.r ..svltfng f,OII'the IbunCf'of .Instellt SCOUdllg
flow".
~~th~t~~lclt'::!It\I~::'I,t~'t ::c;u~hlPlnfutl~.~~t~~~~I.Of T~~t'u:::,o::~
'Ur••",flow,ndllll"nt.,nd th"1'1lII1 r.gl_io :rofteet thr IntelJrllllln of the
h)'drolo9)"e;teoI09W'••nd cliNt..of thlP trlbvtlr)'drltllllje.Ihe physical
Iltrlbbt.,of trlbvUr)'h,bitll ,re not dePf'ndlPnt on ..lnll81 conditions.
~~;~d';tI~~~~:,l:;:,':r:r':~~~::;~~c~~~nt~(lft"ftt:t:::t~:t:~:
"nw"st,•••IJtt"nt of thlP trlhutu)'p1ulfte-""'ch "dtnds Into th.Nlnstr",
SbsHn.Iher or slough .ADUG '961c.1901b).
L.k.1t,blt.t consists of vlrlOlls h;lnllc IPnvlrOnn'nts thlt occur "Uht"
Uir~j,ftiiIAlvl!f'dr.ln.lJr.'hue h,b'Uls r.nlJe fr(HII s..l1.sh,It[MII.
ISoUld.d hlu pt!rched on th~lund,.to lIr9tr.dreper Ilk"_Meh
connect to the Nlnstetll Sulttn,Iher throtlgh ...11 deflnlPd trlbuhr)'
s)'stetlJs.Ihr:tI..,,eCllve thlPlr Niler fre-sprtngs,surhcr runDff
.nd/ur t"lbu..r1p~,
ALASKA POWER AUTHORITY
SUSITN~HYDROELECTRIC PROJECT·
GENERAL HABITAT CATEGORIES OF THE SUSITNA RIVER -
A CONCEPTUAL DIAGRAM (SOURCE:AEIDC,MODIFIED BY
ADF&G 19828.)
FIGURE 2
Woodward·Clyde Consultants
and
ENTRIX.INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
-
The objectives of the three groups of this continuing program
are:
(1)AA.-determine the seasonal distribution and
relative abundance of adult anadromous fish
popUlations produced within the Susitna River
drainage:
(2)RJ -determine the seasonal distribution and
relative abundance of selected resident and
juvenile anadromous fish popUlations within the
Susitna River drainage;and
(3)AH -characterize the seasonal habitat
requirements of selected anadromous and resident
fish species within the Susitna River drainage.
A summary of the significant accomplishments to date by the
three sections of ADF&G's Su Hydro Group is outlined below.
Adult Anadromous
a.Documented migrational timing of salmon runs in the
Susitna River.
b.
c.
d.
Estimated popUlation size and relative abundance of
salmon in sub-basins of the Susitna River.
Estimated total slough escapements for salmon in
sloughs upstream of RM 98.6.
Estimated relative abundance of spawning salmon in
tributaries upstream of RM 98.6.
6
""'"
e.Quanti:Eied selected biological characteristics for
salmon stocks in the Susitna River (i.e.sex ratio,
fecundity,age and lenqth).
f.Determined migrational timing,relative abundance,sex
ratio,age composition and length of eulachon.
g.Documented migrational timing of Bering cisco.
Resident and Juvenile Anadromous
-
a.
b.
c.
d.
Estima1:ed population size for Arctic grayling
popula1:ions in the proposed impoundment areas.
Identified important spawning areas for selected
resident species.
Estimated the relative utilization of macrohabitat
types for juvenile salmon and selected resident
species.
Developed habitat suitability criteria for juvenile
salmon and selected resident species.
e.Estima1:ed population size and survival for juvenile
chum and sockeye.
f.Defined outmigration timing for juvenile salmon.
--,
Aquatic Habitat and Instream Flow
a.Collec1:ed physical and chemical water quality data
describing macrohabitat types.
-b.Identified aquatic macrohabitat types within the middle
reach of the Susitna River (RM 98.6 -152).
7
c.Defined seasonal timing and utilization of adult salmon
in macrohabitat types.
-d.Developed site-specific habitat responses to mainstem
discharge.
e.Developed habitat criteria for adult and juvenile
salmon,eUlachon,Bering cisco,and selected resident
species.
f.Evaluated the passage of adult salmon into selected
sloughs.
-
-
g.Confirmed the importance of ground water upwelling for
spawning salmon in sloughs.
For a list of ADF&G Susitna Hydro references,see Appendix A.
8
~-
3.01 INTRODUCTION TO FISH RESOURCES
3.1 OVERVIEW OF IMPORTANT SPECIES
Fishery res,ources in the Susitna Rive'r comprise a major portion
of the Cook Inlet commercial salmon harvest and provide fishing
opportunitiies for sport anglers.Anadromous species that form
the base of these fisheries include five species of Pacific
salmon:chinook,coho,chum,sockeye and pink.ether
anadromous species present in the Susitna River include
eulachon and.Bering cisco.
The Susitna River is a migrational corridor,spawning area and
juvenile re,aring area for the five species of salmon from its
point of di.scharge into Cook Inlet (RM 0)to Devil Canyon (RM
152),where salmon are usually prevented from moving upstream
by a high velocity barrier.Sloughs and tributaries provide
mos't of thEl spawning habitat for salmon,while the mainstem,
sloughs,and tributary mouths are important ,habitats for
juvenile salmon rearing and overwintering (Barrett et ale 1984,
Schmidt et al.1984).
Important resident species found in the Susitna River basin
include Arctic grayling,rainbow trout,lake trout,burbot,
Dolly VardeJl and round whitefish.Scientific and common names
of all fish species observed in the Susitna River basin are
listed in Tn.ble 1.
3.2 CONTRIBUTION TO COMMERCIAL FISHERY
with the exception of sockeye and chinook salmon,the majority
of the upper Cook Inlet commercial catch of salmon originates
in the Susitna Basin (Barrett et ale 1984).The upper Cook
Inlet area :ls that portion of Cook Inlet north of Anchor Point
and Chinitna Bay (Figure 3).The long-term average annual
catch of 3.0,million fish is worth approximately $17.9 million
in 1984 dollars to the commercial fishery _(K.Florey,ADF&G,
9
Table 1.Co1mnon an:i scientific names of fish species observed in the susitna
Basin.
--
scientific Nama
Petrt:xnyzontidal:!
I.ampetra :japonica
Salmcmi.dae
Coregonus 1aurettae
CoregOIlUS pidschian
OnCOrhyndlUS gol:buscha.
Oncorhynchus keta
9ncorhyncl1us kisutch
Oncorhynchus nerka
oncorhyndlus tshawytscha
Prosopium cy1indraceum
Salmo~eri
Salvelinu.c;ma.l.ma
Salve1~namaycush
Thymal,lus arcticus
Osmeridae
'Ihaleicht112§pacificus
Esocidae
Esox lucius
catostamidae
castostomus catostomus
Gadidae
Iota.lota.
Gasterosteidae
GasterostEros acu1eatus
*Pungitius pungitius
cottidae
Cottus sp ..
Conunon Name
Arctic lamprey
Berin;J cisco
hulTpback whitefish
pink salmon
chum salmon
coho salmon
sockeye salmon
chinook salmon
roon:i whitefish
rai.nb<::M trout
I):)lly Varden
lake trout
Arctic gray1in;J
eulachon
nort:hem pike
longnose sucker
threespine stickleback
ninespine stickleback
sculpin
SClUrC"..e:ADF&G 1981a,b;1982a;1983b;Barrett et ale 1984;schmidt at ale
1984;Sautner an:i stratton 1984.
*U11published data,ADF&G SU Hydro,Anchorage,Alaska.
10
J I 1 J 1 j 1 ]j J J j t )J 1
I(ASILO'".
J
/C(NTltAL DlITIlIeT
.'
(
CItESCfNT It '>
TUll(DHI '\••J'"
uv-"''''''
-"'\()
)
.........."'.~.....L~TU .....~~•..-....,.......N.
'"
{:I SUSlT~It VI(NIIl ••"L..•1 " .,,"NiM i'-
.'.......;.;';":Y:}!r···....../..'
CHUTNA It.).,.••./\....'..1/'..../-~.
,.....,...,........./'"r"It.'NORTHf-U V {ANCHORAG(
...AftT.....":.:"n "-"i ..-...-'"...'V'..~""~,/..\'",
'"""...N.J ..'\......"-.\,./....,--..'......\\;/..........-...."'.-........'\'-.........'.A \_..-...-"'..\
.............'.../"
"'CE \fAST "
)/':NTRAL •'OIl£LAND
0I1T1t1CT \.i'i:f-.....:1 I(~NAI It.
)\
.:\~
./I'
,"../j.u .
v"')!
i (ANCHOII rT.
......
......
UPPER COOK INLET COMMERCIAL SALMON MANAGEMENT AREA
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 3
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
sus IT NA JOINT VENTURE
-
-
pers.COmIn.1984).In recent years commercial fishermen have
landed record numbers of salmon in the upper Cook Inlet fishery
(Figure 4);over 6.7 million salmon were caught in 1983 and
over 6.2 million fish in 1984.The Susitna River is the most
important s,almon-producing system in upper Cook Inl"'ot (ADF&G
1982a;BarrEatt et al.1984,1985);however,the quantitative
contribution of the Susitna River to the commercial fishery can
only be approximated because of:
o th.e high number of intra-drainage spawning and
re:aring areas;
o the lack of stock separation programs (except for
sockeye salmon);and
-
o th.e lack of data on other known and suspected
sa,lmon-producing systems in upper Cook Inlet;
".,..
o overlap in the migration timing of mixed stocks
and species in the Cook Inlet harvest areas.
Therefore,'the estimates of contributions of Susitna River
salmon to the upper Cook Inlet fishery should be viewed as
approximations.
3.2.1 Sockeye Salmon
The most important species in the upper Cook Inlet commercial
fishery is sockeye salmon.In 1984,the total sockeye harvest
of 2.1 million fish was valued at $13.5 million (K.Florey,
ADF&G,pers.comm.1984).The commercial sockeye harvest has
averaged 1.34 million fish annually in upper Cook Inlet for the
last 30 years (Table 2).The estimated contribution of Susitna
River sockeye to the commercial fishery is between 10 to 30
percent (Barrett et al.1984).This represents an estimated
annual commercial harvest of between 134,000 to 402,000 Susitna
River sockeye over the last 30 years.In 1983,Susitna River
12
8 ......·-------------------------..,
-0').
0
0
0.
0
0
0 .4....-
Z--:2:
IF'"(.)
~<(.)
2
1985198019751970196519601955
O'....---.,.-----,---...,..---.....---r----....,.----;
19510-
YEAR
COMMERCIAL CATCH OF UPPER COOK INLET SALMON t 1954-1983.
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 4
Woodward~Clyde-Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
13
Table 2.camnercial catch of upper Cook Inlet sa1:mon in numbers of fish by
species,1954 -1984.
14
-
sockeye contributed approximately 500,000 fish to the total
catch of 5 million (Table 3).The 1983 commercial sockeye
catch was the highest in 30 years of record (Figure 5).
3.2.2 Chum Salmon
Chum salmon and coho salmon are about equal in importance in
the upper Cook Inlet commercial fishery and rank second and
third in va.lue after sockeye eK.Florey,ADF&G,pers.comm.
1984).The upper Cook Inlet chum salmon catch has averaged
659,000 fish annually since 1954 (Table 2).The contribution
of Susitna River chum to the upper Cook Inlet fishery is about
85 percent (Barrett et al.1984).This contribution represents
an estimated annual chum harvest of 560,000 Susitna River fish
in the commercial harvest over the last 30 years./In 1982,the
Susitna River contributed approximately 1.21 million fish
(Table 3)of the record harvest of 1.43 million chum salmon
taken in thE!upper Cook Inlet fishery (Table 2;Figure 6).In
1984,the t.otal chum salmon harvest of 684,000 fish in the
commercial fishery was valued at $2.0 million (K.Florey,
ADF&G,pers.comm.1984).
3 •2 "3 Coho Salmon
since 1954,the upper Cook Inlet coho salmon commercial catch
has averaged 264,000 fish annually (Table 2).Approximately 50
percent of the commercial coho harvest in upper Cook Inlet is
from the Susitna River (Barrett et al.1984)•This
contribution represents an average annual Susitna River coho
harvest of 132,000 fish in the commercial fishery over the last
30 years.In 1982,the Susitna r~iver contributed an estimated
388,500 fish.(Table 3)to a record harvest of 777,000 coho
taken by the:upper Cook Inlet fishery (Figure 7).In 1984,the
total coho lsalmon harvest of 443,000 fish in upper Cook Inlet
had a worth of $1.8 million (K.Florey,ADF&G,pers.comm.
1984).
15
J J ]]1 )J ]]1 J J
Table 3.Summary of commercial and sport harvests on Susitna River basin adult salmon returns.
Commercial Harvest Sport Harvest
Upper Estimated Estimated Estimated Susistna
Cook Inlit Estimated Susitna Susitna Total Basin Sp~rt Percent of2SpeciesHarvestPercentSusitnaHarvestEscapementRunHarvestEscapement
Sockeye 14ean Range 287,000~81 1,443,000 20 (10-30)288,600 575,1./00 1,283 0.4
82 3,237,000 20 (10-30)647,400 279,0003 926,400 2,205 0.8
83 5,003,000 10 (10-30)•500,300 185,0005 685,300 5,537 3.0
84 2,103,000 20 (10-30)420,600 605,800 1,026,400
Pink 381128,000 85 108,800 127,0003 235,800 8,660 6.8
82 789,000 85 670,650 1,318,0003 1,988,650 16,822 1.3
83 74,000 85 62,900 150,000 5 212,900 4,656 3.1
84 623,000 85 529,550 3,629,900 4,159,450
I-'Chum 297,000~0'\81 843,000 85 716,550 1,013,550 4,207 1.4
82 1,429,000 85 1,214,650 481,0003 1,695,650 6,843 1.4
83 1,124,000 85 955,400 290,0005 1,245,400 5,233 1.8
84 684,000 85 581,400 812,700 1,394,100
Coho 68,000~81 494,000 50 247,000 315,000 9,391 13.8
82 777,000 50 388,500 148,0003 536,500 16,664 11.3
83 521,000 50 260,500 45,0005 305,500 8,425 18.7
84 443,000 50 221,500 190,100 411,600
Chinook
81 11,500 10 -1,150 7,576------
82 20,600 10 2,060 -.-..-10,521
83 20,400 10 2,040 .--12,420
84 8,800 10 880 250,0006 251,000
-----------------------------
12 Source:ADF&G Commercial Fisheries Division .
3 B.Barrett,ADF&G Su Hydro,February 15,1984 Workshop Presentation
5%for chumYentnastation+Sunshine Station estimated escapement +5%for sockeye,+48%for pink,+
4 +85%for coho (Source:B.Barrett,ADF&G SU Hydro,February 15,1984 Yorkshop Presentation).
5 Mi lls 1982,1983,1984
6 Flathorn Station (RM 22)Escapements (Barrett et al.1985)
Source:Barret t et a l.1985
-8_-------------------------,
5
-.
-!I'
0c
0 .
C
C 30.
p
Z--:c
0 2l-
F!""<0
Jll'l!!lfa 1
1985198019751970196519801955
O....,--.....---~--__r---.....--~---.,..--.....
1950
YEAR
COMMERCIAL CATCH OF UPPER COOK INLET SOCKEYE;1954-1983.
-ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROjECT
FIGURE 5
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
17
2-.---------------------------.
1.5-fI).
0
0
0 .
.""""0
0
0.,-
Z 1---::J:
(J
II"""t-oe
(J
~0.5
1985198019751910
YEAR
196519601955
0-&-.------------.,.....--.....---.,...--.....,r------4
1951J-
COMMERCIAL CATCH OF UPPER COOK INLET CHUM,1954-1983.
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 6
Woodward-Clyde Consultants
and
ENTRIX,INC•.
HARZA-EBASCO
SUSITNA JOINT VENTURE
18
"""
,~
80
~
71J
~
eo
,~
-en,.-.
0
0
0 .
0
(~
,..
z--:z:
~u
~<"U
~
10
1985198019751970196519601955
o-l-'--......---....---..,..--.....---,.----r----1
1950
YEAR
COMMERCIAL CATCH OF UPPER COOK INLET COHO,1954-1983.
-~
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
,~
FIGURE 7
--
Woodward.Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCv
SUSITNA JOINT VEIIITURE
19
-
-
I~
3.2.4 Pink Salmon
Pink salmon is the least valued of the commercial species in
upper Cook Inlet.The upper Cook Inlet average annual odd-year
harvest of"pink salmon since 1954 is about 120,000 fish,with a
range of 12,500 to 544,000 fish.The average annual even-year
harvest is approximately 1.58 million pink salmon with a range
of 0.48 to 3.23 million fish (Table 2;Figure 8).The
estimated contribution of Susi'cna River pink salmon to the
upper Cook Inlet pink fishery is 85 percent (Barrett et ale
1984).This represents an average annual Susitna River
contribution of 0.10 million odd-year and 1.34 million
even-year pink salmon to the upper Cook Inlet fishery over the
last 30 years.In 1984,the total pink salmon harvest of
623,000 fish in upper Cook Inlet was worth an estimated $0.5
million (K.Florey,ADF&G,pers.comm.1984).
3.2.5 Chinook Salmon
The commercial chinook harvest has averaged 19,200 fish
annually in the upper Cook Inlet fishery over the last 30 years
(Table 2;Figure 9).Since 1964,the opening date of the
commercial fishery has been June 25.The Susitna River chinook
run begins in late May and peaks in mid-June.Thus,by June 25
the maj ority of chinook have already passed through the area
sUbject to commercial fishing.Catches of chinook salmon have
averaged 11,600 fish annually for the 20~year period of
1964-1983.Approximately,10 percent of the total chinook
harvest in upper Cook Inlet are Susitna River fish (Barrett et
ale 1984).This represents an average annual contribution of
1,960 chinook to the upper Cook Inlet fishery for the last 30
years,or 1,160 fish for 1964-1983.In 1984,the 8,800 chinook
caught in the upper Cook Inlet fishery were valued at $0.3
million (K.Florey,ADF&G,pers.comm.1984).
20
-
,~
198519801975197019601955
o~--"::::===;r====::::::r====;;;:;r:~--r--""":::""'---=~
1950
.-
3 EVEM-YEAR-~en.
0
0
0 ..
0
0
0 ..
po
Z 2--:::cu...cu
-.1
YEAR
COMMERCIAL CATCH OF UPPER COOK INLET PINK,1954-1983.
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 8
Woodward-Clyde Consultants
and
ENTRfX,fNC.
HARZA-ESASCO
SUSITNA JOINT VENTURE
21
701_----------------------------,
--CI)
'0O·
ct
~~
z--:c..-(J
l-ce
(J
20
"""
10
-
-
1955 1960 1965
YEAR
I
1970 1975 1980 1985
COMMERCIAL CATCH OF UPPER COOK INLET CHINOOK,1954-1983.
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 9
Woodward-Clyde Consultants
and
ENTRIX,INC.
22
HARZA-EBASCO
SUSITNA JOINT VENTURE
-
3.3 SPORT FISHING
Increases in population and tourism in Alaska have resulted in
a growing demand for recreational fishing.Recreational
fishing is now consisered a significant factor in total
fisheries management,particularly in Cook Inlet where
commercial and non-commercial user conflicts have developed
(Mills 1980).The Susitna River and its major salmon and
resident fish-producing tributary streams provide a
mUlti-species sport fishery.Since 1978,the drainage has
accounted for an average of 127,100 angler days of sport
fishing effort,which is approximately 9 percent of the
1977-1983 average of 1.4 million total angler days for Alaska
and 13 percent of the 1977-1983 average of 1.0 million total
angler days for the Southcentral reg'ion (Mills 1979,1980,
1981,1982, 1983,1984).
The sport fish harvests for 1978 through 1983 from the Susitna
Basin,based on mail surveys to a sample of license holders,'
are shown in Table 4 (Mills 1979,1980,1981, 1982,1983 and
1984)•The estimates represent the sport fishing harvests
throughout the Susitna Basin and include an area that is larger
than that which could be affected by the proposed project (see
Figures 10 and 11 for locations of most of the major
tributaries listed in Table 4).
3.3.1 Arctic Grayling
The annual Arctic grayling sport harvest has averaged 18,200
fish in the Susitna Basin and 61,500 fish in southcentral
Alaska over the last six ye~rs (Table 5).The largest sport
harvest of Arctic grayling on record;in the Susitna Basin
occurred in 1980 when an estimated 22,100 fish were caught.
This represents about 32 percent of the total Southcentral
Arctic grayling harvest in 1980 (Mills 1981).
23
)1 )-)')1 }~I 1 )J 1 ))j
Table 4.Susitna Basin sport fish harvest and effort by fishery and species -1978,1979, 1980, 1981,1982 and 1983.
------
Days Chinook Coho Sockeye Pink Chum Rainbow Dolly lake Arctic
locations Fished Salmon Salmon Salmon Salmon Salmon Trout Varden Trout Grayling 8urbot
------------
1978
Willow Creek 22,682 47 905 56 18,901 2,458 913 280 0 208 9
Caswell Creek ...
Montana Creek 25,762 408 2,451 85 15,619 4,429 1,193 633 0 958 9
Sunshine Creek .-.
Clear (Chunilna)Creek 5,040 12 2,200 28 2,074 1,912 1,501 1,817 0 859 27
Sheep Creek 11,869 256 478 14 6,981 1,697 470 108 0 461 18
little Willow Creek 5,687 0 151 28 3,142 1,015 334 63 0 334 D
Deshka Rher 9,111 850*1,798 0 697 0 3,634 0 0 579 0
lake creek 8,767 326*2,212 254 2,833 1,015 2,721 154 36 2,115 45
At'exander Creek 6,914 769*2,401 183 1,146 215 2,640 136 0 1,871 0
Talachulitna River 732 12*88 141 31 234 0 235 0 99 0
lake louise,lake Susitna,
Tyone River 13,161 0 0 0 0 0 0 0 2,522 2,278 2,947
Others 14.970 163 2,388 56 3,994 2,692 1,519 2,739 877 3,770 208
!V 1978 Total 124,695 2,843 15,072 845 55,418 15,667 14,925 6,165 3,435 13,532 3,263
~---------
1979
Willow Creek 18,911 459 462 94 3,445 582 1,500 618 0 1,654 18
Caswell Creek 3,710 156 624 0 100 9 282 91 0 354 0
Montana Creek 22,621 312 1,735 346 2,472 745 1,536 527 0 791 9
Sunshine Creek 3,317 10*774 157 700 55 382 264 0 0 45
Clear (Chunilna)Creek 5,125 312 1,248 31 645 355 1,373 827 0 1,045 9
Sheep Creek 6,728 10 462 31 2,418 682 573 127 0 645 64
little Willow Creek 5,171 0 262 141 745 118 345 336 0 1,091 0
Deshka River 13,236 2,811 973 0 109 0 3,182 0 0 1,463 82
lake Creek 13,881 1,796 2,671 440 882 136 4,527 164 9 1,963 109
Alexander Creek 8,28it 712 1,560 79 236 45 1,182 182 0 745 145
Talachulitna River 2,185 293 125 47 100 55 0 155 0 664 45
lake louise,lake Susitna,
Tyone River 12,199 0 0 0 0 0 0 0 2,618 2,936 2,363
Others 12,639 39 1,997 220 664 1,245 3,472 909 472 4,918 282
1979 Total 128,007 6,910 12,893 1,586 12,516 4,072 18,354 4,200 3,099 13,342 3,171
----------------------
*Chinook less than 20 inches
)I I J 1 1 -l i -1 ).~)-)i l
Table 4.(Continued)
-----~~---~---------------------------------------------------------------------------------------------------------------------------------------------
Days Chinook Coho Sockeye Pink Chum Rainbow Dolly Lake Arctic
Locations Fished Salmon Salmon Salmon salmon Salmon Trout Varden Trout Grayli ng Burbot
-------------------------------------
1980
Willow Creek 29,011 289 1,20it 83 23,638 989 1,168 636 0 1,868 0
Caswell Creek 4,963 215 1,124 77 1,663 19 154 83 0 353 26
Montana Creek 19,287 559 2,684 257 8,230 571 854 167 0 655 13
Sunshine Creek 5,208 132 1,534 116 2,408 225 193 39 0 0 39
Clear (Chunilna)Creek 4,388 172 661 6 622 385 950 751 0 1,348 32
Sheep Creek 8,041 45*430 9 6,362 648 385 83 0 725 45
Little Willow Creek 8,190 32*494 77 6,420 270 353 122 0 1,156 0
Deshka River 19,364 3,685 2,290 0 689 0 4,305 0 0 1,817 224
Lake Creek 8,325 775 2,351 267 2,101 69 2,144 121 9 1,972 0
Alexander Creek 6,812 1,438 999 52 809 121 1,945 353 0 1,145 0
Talachulitna River 2,542 121 491 112 276 17 379 982 0 1,713 0
Lake Louise,Lake Susitna,
Tyone River 10,539 0 0 0 0 0 0 0 2,609 4,477 6,612
Others 12,216 45*2,234 257 3,403 1,445 2,65l'790 267 4,854 212
1980 Total 138,886 7,389 16,499 1,304 56,621 4,759 15,488 4,127 2,876 22,083 7,203
-
l\J --------
U1 Days r.hinook Chinook Coho Sockeye Pink Chum Rainbow Dolly Lake Arctic
Locations Fished salmon*Salmon Salmon
Salmon Salmon Salmon Trout Varden Trout Grayl i ng Burbot
-----------------
1981
Willow Creek 14,060 144 441 747 77 2,797 1,533 1,475 249 0 1,188 48
Caswell Creek 3,860 77 172 901 38 335 0 326 38 0 144 0
Montana Creek 16,657 239 422 2,261 182 1,782 805 1,111 240 0 891 0
Sunshine Creek 3,062 57 0 968 220 958 125 249 10 0 57 115
Clear (Chunilna)Creek 3,584 86 287 422 29 19 57 1,226 1,418 n 996 0
Sheep Creek 6,936 0 0 326 105 1,236 987 201 57 0 872 0
Little Willow Creek 3,845 0 0 29 -67 604 192 374 48 0 623 0
Deshka River 13,248 738 2,031 632 0 19 0 3,631 10 0 1,255 96
Lake Creek 6,471 163 632 1,035 211 412 48 2,874 67 19 1,600 29
Alexander Creek 6,892 278 843 891 67 57 10 2,290 287 0 1,130 29
Talachulitna River 1,378 57 0 240 172 29 0 0 0 0 479 0
Lake Louise,Lake Susitna,
Tyone River 14,397 0 0 0
0 0 0 0 0 4,093 4,892 5,292
Others 7,850 277 0 939 115 412 450 3,851 814 287 7,089 57
1981 Total 102,240 2,748 4,828 9,391 1,283 8,660 4,207 13,757 3,238 4,399 21,216 5,666
------------------------------------
*Chinook less than 20 inches.
-~~l )}~-~1 )-j -}1 --J --])J j ~]111
Table 4.(Continued>
-----------------------------------------------------------------------------------------------------------------------~--------------------------------
Days Chinook Chinook Coho Sockeye Pink Chum Rainbow Dolly Lake Arctic
Locations Fished Salmon*Salmon Salmon Salmon Salmon Salmon Trout Varden Trout Grayl i ng Burbot
------
1982
Willow Creek 19,704 220 409 1,069 94 4,789 2,086 891 262 0 1,520 63
Caswell Creek 5,101 178 293 776 52 1,092 °189 73 °252 0
Montana Creek 23,645 126 115 3,060 514 3,595 1,708 2,243 356 0 849 0
Sunshine Creek 3,787 52 0 1,719 189 1,132 231 545 42 0 42 73
Clear (Chunilna)Creek 3,856 52 398 996 115 220 31 608 1,069 0 943 0
Sheep Creek 9,093 0 0
367 88 2,599 1,750 325 409 0 723 0
Little Willow Creek 5,579 0 0
398 105 1,520 199 335 189 0 377 0
Oeshka River 18,391 1,142 3,165 2,463 0 377 0 3,804 0 0 1,457 252
Lake Creek 8,649 356 1,289 1,603 252 398 199 3,134 482 0 1,955 0
Alexander Creek 10,748 681 1,825 1,907 335 482 0 2,505 42 0 1,582 84
Talachulitna River 1,911 0 0 524 63 220 0 0 31 0 587 0
Lake Louise,Lake Susitna,
Tyone River 14,024 0 0 0 0 \0 0 0 0 4,056 3,532 5,565
Others 9,980 220 0 1,782 398 398 639 2,400 1,666 335 5,041 63
1982 Total 134,468 3,027 7,494 16,664 2,205 16,822 6,843 16,979 4,621 4,391 18,860 6,100
---
tv 19830\
Willow Creek 13,405 136 398 576 425 1,647 1,490 1,689 336 0 1,794 21
Caswell Creek 5,048 10 262 408 151 126 0 231 157 °315 31
Montana Creek 17,109 199 305 1,402 534 902 1,311 1,332 325 0 336 0
Sunshine Creek 3,429 105 0 722 685 241 42 178 84 0 31 367
Clear (Chunilna)Creek 7,564 252 682 836 534 73 650 1,836 1,962 0 1,553 84
Sheep Creek 6,237 °0 596 370 682 902 409 52 0 839 10
Little Willow Creek 2,791 0 0 52 110 157 147 514 73 0 84 0
Oeshka River 23,174 934 3,955 1,036 0 21 °2,434 0 0 1,280 126
Lake Creek 14,749 535 1,888 1,392 726 430 52 2,287 262 0 2,224 283
Alexander Creek 9,425 672 1,039 408 69 126 0 608 136 0 483 0
Talachulitna River 4,556 63 273 84 41 0 0 0 105 0 3,178 0
Kashwitna River 1,344 231 0 52 0 0 0 357 304 0 514 0
Lake Louise,Lake Susits~Q
Tyone River 12,948 0 0 0 °°0 0 0 3,210 4,217 4,070
Others 12,367 303 178 861 1,892 251 639 4,625 1,067 287 3,387 534
1983 Total 134,156 3,440 8,980 8,425 5,537 4,656 5,233 16,500 4,863 3,497 20,235 5,526
~----------------------------------
*Chinook less than 20 inches
Source:Mills (1979-1984)
15 KlIomelers
Flathorn
Station
(RM 22)
_-,;.5---":'1°Miles
o 5 10
COOK INLET
SUSITNA RIVER AND MAJOR TRIBUTARIES FROM
MOUTH TO SHEEP CREEK.
,....ANCHORAGE
"'-.......J
lIlLASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 10
Woodward-Clyde Consultants
and
ENTRIX,INC.
27
HARZA-EBASCO
SUSITNA JOINT VENTURE
-
0 o S 10 Miles....)
0 5 10 15 KilornelEls~
SUSITNA RIVER AND MAJOR TRIBUTARIES
FROM SHEEP CREEK TO DEVIL CANYON.
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 11
Woodward.Clyde Consultants
and
ENTRIX,INC.
28
HARZA-EBASCO
SUSITNA JOINT VENTURE
'i .~1 ))j j 1 1 1 1 -J )1 J )j 1 1
Table 5.sport fish harvest for Southcentral Alaska and Susitna Basin in numbers of fish by species,1978-1983.
----------------
Arct ic Grayli ng Rainbow Trout Pink Salmon Coho Salmon Chinook Salmon Chum Salmon Sockeye Salmon
South-Susitna South'Susitna South-Susitna South'Susitna South'Susitna South-Susitna South'susitna
Year central Basin central Basin central Basin central Basin central Basin central Basin central Basin
1978 47,866 13,532 107,243 14,925 143,483 55,418 81,990 15,072 26,415 2,843 23,755 15,667 118,299 845
1979 70,316 13,342 129,815 18,354 63,366 12,516 93,234 12,893 34,009 6,910 8,126 4,072 77,655 1,586
1980 69,462 22,083 126,686 15,488 153,794 56,621 127,958 16,499 24,155 77,389 8,660 4,759 105,914 1,304
1981 63,695 21,216 149,460 13,757 64,163 8,660 95,376 9,391 35,822 7,576 7,810 4,207 76,533 1,283
1982 60,972 18,860 142,579 16,979 105,961 16,822 136,153 16,664.46,266 10,521 13,497 6,843 128,015 2,205
1983 56,896 20,235 141,663 16,500 47,264 4,656 87,935 8,425 57,094 12,420 11,043 5,233 170,799 5,537
N
\0
Average 61,535 18,211 132,908 16,000 even-134,413 even'42,954 103,774 13,157 37,294 7,943 12,149 6,797 112,869 2,128
odd-58,264 odd-8,611
Source:Mills <1979'1984)
--
3.3.2 Rainbow Trout
The Susitna Basin and Southcentral Alaska annual rainbow trout
sport harvests have averaged 16,000 and 132,900 fish
respectively since 1978 (Table 5).In 1979,about 18,350
rainbow trout were harvested by anglers in the Susitna Basin,
which represents approximately 14 percent of the Southcentral
region rainbow trout sport catch in 1979 (Mills 1980).
3.3.3 Pink Salmon
The annual even-year pink salmon sport harvest has averaged
42,950 fish in the Susitna Basin and 134,400 fish in
Southcentral Alaska since 1978 (Table 5).The annual odd-year
pink salmon sport catch has averaged 8,600 fish in the Susitna
Basin and 58,300 fish in Southcentral Alaska since 1979 (Table
5).The largest sport harvest of pink salmon on record in the
Susitna Basin occurred in 1980 when an estimated 56,600 fish
were caught (Mills 1981).In 1981,the estimated.odd-year pink
salmon sport harvest of 8,700 fish represented about 6.8
percent of the estimated Susitna escapement of 127,000 pink
salmon (Table 3).
3.3.4 Coho Salmon
Since 1978,the Susitna Basin and Southcentral Alaska annual
coho salmon sport harvests have averaged 13,200 and 103,800
fish respectively (Table 5).In 1982,about 16,664 coho were
landed by anglers in the Susitna Basin.(Mills 1983),which is
the largest annual catch on record.In 1983,almost one of
every five coho entering the basin was caught bi'sport anglers
(Table 3).
3.3.5 Chinook Salmon
The annual chinook salmon sport harvest has averaged 37,300
fish in Southcentral Alaska and 7,950 fish in the susitna Basin
30
since 1978 (Table 5).This represents an annual Susitna Basin
contribution of 21 percent to the Southcentral chinook sport
harvest over the six year period.The largest Susitna Basin
sport harvest of chinook salmon on record occurred in 1983,
when 12,420 fish were caught by fishermen (Mills 1984).
3.3.6 Chum Salmon
The Susitna Basin and Southcentral Alaska annual chum salmon
sport harvests have averaged 6,800 and 12,150 fish respectively
since 1978 (Table 5).The largest sport catch of chum salmon
on record in the Susitna Basin occurred in 1978 when 15,700
fish were landed (Mills 1979).For the years 1981 to 1983,
chum salmon sport harvests have averaged between 1.4 and 1.8
percent of the estima~ed Susitna Basin chum salmon escapement
(Table 3).
3.3.7 Sockeye Salmon
ITheannualsockeyesalmonsportharvesthasaveraged 112,900
fish in Southcentral Alaska and 2,100 fish in the Susitna Basin
for the years 1978 through 1983 (Table 5).In 1983 over 5,500
sockeye salmon were caught by fishermen in the Susitna Basin,
which is the largest annual catch on record (Mills 1984).The
sport catch of sockeye fJ:'om 1981 through 1983 has averaged 3
percent or less of the estimated Susitna Basin sockeye
escapement (Table 3).
3.4 SUBSISTENCE FISHING
The only subsistence fishery on Susitna River fish stocks that
is officially recognized and monitored by the Alaska Department
of Fish and Game is near the village of Tyonek,approximately
30 miles (50 km)southwest of the Susitna River mouth.The
Tyonek subsistence fishery was reopened in 1980 after being
closed for sixteen years.From 1980 through 1983,the annual
Tyonek subsistence harvest averaged 2,000 chinook,250 sockeye
and 80 coho salmon (ADF&G 1984).
31
"""
-
4.0 SPECIES BIOLOGY
4.1 ADULT SALMON
Adult salmon escapements have be~n monitored at various
sampling stations in the Susitna Basin.The locations of these
stations are shown in Figures 10 and 11.The methodology used
by ADF&G to monitor salmon escapements can be found in reports
cited in the text.
4.1.1 Sockeye Salmon
(i)Timing of Runs
Sockeye salmon enter the Susitna River in two distinct runs
(Barrett et ale 1984,1985).The first run of fish enters the
river in late May to early June and passes Sunshine station (RM
80)between the first and third weeks of June (Barrett et ale
1984,1985).The escapement of first-run sockeye at Sunshine
station was about 5,800 fish in 1982,3,300 fish in 1983 and
4,800 fish in 1984 (Barrett et ale 1984,1985).First-run
sockeye spawn upstream of RM 80 in the Papa Bear lake system in
the Talkeetna River drainage (RM 97.1)(AOF&G 1982a,Barrett et
ale 1984).Peak spawning activity in the Papa Bear Lake inlet
stream was between the third week of July and the first week of
August in 1982 and between the second and fourth weeks of July
in 1983 and 1984 (ADF&G 1982a;Barrect et ale 1984,1985).
Because first-run sockeye salmon spawn upstream of RM 80
exclusively in the Talkeetna River drainage,which will not be
influenced by the project,they are not discussed in further
detail.
Second-run sockeye enter the Susitna River about the last of
June.In 1981 through 1984 fish passed Sunshine station
between the third week of July and the second week of August
(Barrett et ale 1984,1985).These fish are abundant in the
32
mainstem of the Talkeetna-to-Devil Canyon reach (RM 98.6-152)
-from about the third week of July to the fourth week of August
(Barrett et ale 1984,1985).A summary of second-run sockeye
migration timing in the Susitna River basin for 1981,1982 and
1983 is presentsd in Figure 12.
Second-run sockeye salmon migration timing is likely influenced
by river discharge.In 1981 river discharge was declining from
over 150,000 cfs when most second-run sockeye passed Sunshine
Station (Figure 13).In 1982 a discharge spike above 80,000
cfs coincided with reduced ADF&G fishwheel catches (Figure 13).
In 1983 river discharge was below 80,000 cfs at Sunshine
station during most of the second-run sockeye migration and the
run passed Sunshine station in one maj or peak (Figure 13).
Based on this analysis ,it appears that spikes in discharge
~
over 100,000 cfs at Sunshine Station can delay sockeye salmon
migration timing.
(ii)Escapement
The total annual minimum escapement of second-run sockeye
salmon in the Susitna River averaged 248,000 fish for 1981
through 1984 (Table 6).This estimate is considered a minimum
because it is based on the summation of escapements at Sunshine
and Yentna stations and does not include escapements downstream
of RM 80,excluding the Yentna River (RM 28).In 1984,
approximately 605,800 second-run sockeye reached Flathorn
Station (RM 22)(Barrett et ale 1985).This estimate is based
on data from the first year of monitoring at this location and
does not include escapements downstream of RM 22 (Barrett et
ale 1985).Most second-run sockeye salmon spawn in the Yentna
(RM 28),Talkeetna (RM 97.1)and Chulitna (RM 98.6)drainages
(Barrett et al.1984,1985).
For 1981 through 1984,second-run sockeye escapements averaged
6,300 fish annually at Talkeetna station (RM 103)(Table 6),
33
~I }1 1 ~I B J ~J 1 J ])1 )J )
CURRY
STATION -
I '..,·..··:1.I 11883
1 r=::=f"::I f 1982
J---f:::··f .;I IH.••••1981
t--------------------------------------------
I I ::';;t:",:::r:;;·:"..;:;:1 1 1983
T:i:i~OT~Ai 1 EEl·"::::;'I 11982
I 1:;:;;,1,'.:I 1 1981
~-------------~-----------------------------
...----,----------------....-----~_.._----------....dian Pili II
Rang.\Calch~r:,.;::~1-1
/\
'0/.Cumulative 950/o C"m"loliwe
Catch ,er Eflort Cll Ich
19831 E:!I;:..;..::··:"d I
18821 ~I
1981'e:;:j!pt<'·;.',:,:;q I ,r--S-EC-O-N-O-R-U-N--'
SOCKEYE SALMON
1883 I EE:i:f;r;;,".,';';:!d':,,
19821 E!:!:f j"•..•I 1
I 9 fJ I I I ......::I:;;;';I 1
YENTNA
STATION ~
SUNSHINE
STATION •w
oJ>o.
t
6/12
,--,-.--.------.'--~'-I~------.-.---',---,-.--,
6/26 7/10 7/24 -8/7 8/21 9/4
, I
9/18
OATE
MIGRATIONAL TIMING OF SECOND-RUN SOCKEYE SALMON BASED ON FISHWHEEL CATCH PER UNIT EFFORT
AT SELECTED LOCATIONS ON THE SUSITNA RIVER IN 1981,1982 AND 1983.(SOURCE:BARRETT et at.1984)
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 12
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSII NA JOINT VENTURE
J 1 1 ...~~J i 1 J j j 1
Ie1111
AU\1.
•,.u"•
.lIlLY
F18HWHEEl CATCH (FC)
DISCHARGE CO)
COMPARISON OF SECOND-RUN SOCKEYE FISHWHEEL CATCH
AND MAINSTEM DISCHARGE AT SUNSHINE STATION (RM 80),
1981-1983.
1982~~'.I,: •I I
:I : \
I.: :~
I I II
I II
\A :
\
I
I.•,
,I....\to,
'.,'--,I •I
'"I',I.~\I.I
.........-....,.}\.._,...1
,
I
~{'\..\ ,I.,I .....'II
I •
I "...,,,
, I..'.
.AllY
OJ
II.
~
o
;;;
~
'I
80
10
4012
11
30-+100
:10+180
18+100 ,
"I'19831981II.,
I',,·I •18-1 I ,
I
,f\80 ·
"
I IUOI \
11 I ,I,n I ~1",I ,, I ,'.,
I o',,'II '
I ,
1'''\:,
I
,:;I \-,\I \
I \:;0 ,0
III I III ,
I
1:1 I \
,,
10 ,,III iii I III Wi ,,X I \0
(--'"§I I X 0 I•I 0 ".I \I I "l 0 ..-
I ,,.,
I I '\0 .,•It 80 ~\ I
I ,
8 ~
,
I •,•%I I 'V"V "\It ,."I •I',I \X I "• I
,.I
X ..I •i ..--.,....I '...II.8 u ,
0 !;!
..-,,........
II.o ,I '\-0u\I I u..
\II.I ,
"'-,4.
4
4-i -',........'0
u...
0:r
X
OJ..
.-...
III
III
X•
w
U1
e-t-,o
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
JULy AUG.
I I 11
UPT.
FIGURE 13
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EOASCO
SUS IT NA JOINT VENTURE
'-1 1 'm )1 1 ~i J J J I J J J ))
Table 6.Average salmn escapements in the SUsitna River by species am location.
Location;
sockeye1 Chum2 Ccl:J.o2 Pink3 Chinook4RiverMile Total
Yentna station 126,750 21,200 19,600 odd 48,400 odd 215,950-RM 28,TRM 04 even 408,300 even 575,850
sunshine station 121,650 431,000 43,900 odd 45,000 88,200 odd 729,750
RM 80 even 730,100 even 1,414,850
Talkeetna station 6,300 54,600 5,700 odd 5,900 16,700 odd 89,200
RM 103 even 125,500 even 208,800
w curry station 2,400 28,200 1,600 odd 3,300 13,000 odd 48,500
CtI RM 120 even 87,900 even 133,100
~SUsitna 248,400 452,200 63,400 odd 93,400 odd 857,500-River even 1,138,400 even 1,902,500
1 Secorrl-nm sockeye escapements.Four-year average of 1981, 1982,1983 am 1984 escapements.
2 Four-year average of 1981,1982,1983 am 1984 ~pements.
3 '00d is average of 1981 ani 1983 escapements.Even is average of 1982 am 1984 escapements.
4 'Ihree-year average of 1982,1983 am 1984 escapements.
5 summation of Yentna station am SUnshine station average escapements.Does not include escapement to the SUsitna
River arrl its tributaries belaw :RM 80 (exclt.1din;J the Yentna River).
Source:Barrett et al.1984,1985
-
with a range of 3,100 to 13,100 (Barrett et a1.1984,1985).
These escapements are overestimates of the number of fish that
spawn upstream of RM 103 because a significant number of fish
return downstream of Talkeetna·station (Barrett et a1.1984,
1985).In 1984,about 83 perc~~t of the sockeye escapement at
Talkeetna station were milling fish that returned downstream to
spawn (Barrett et a1.1985).If the 1984 escapement (13,100
fish)to Talkeetna station is reduced to account for this
milling component of the run,spawning sockeye salmon in the
Talkeetna-to-Oevi1 Canyon reach accounted for about 0.5 percent
of the 1984 second-run sockeye escapement to F1athorn station
(Barrett et a1.1985).In 1983 about 72 percent of the sockeye
escapement to Talkeetna station (4,200 fish)were considered
milling fish that returned downstream of Talkeetna Station to
spawn.The milling components of the sockeye escapements to
Talkeetna Station were not estimated in 1981 or 1982.
,\
(iii)Migration Rate
Tagged,second-run sockeye salmon migrated the 23 miles between
Sunshine station (RM 80)and Talkeetna station (RM 103)at an
average rate of travel of 4.6 miles per day (mpd)in 1981,2.7
mpd in 1982,2.4 mpd in 1983 and 5.8 mpd in 1984 (Barrett et
a1.1984,1985).The average rate of travel for tagged,
second-run sockeye between Talkeetna station and Curry station
(RM 120)was:3.5 mpd in 1981,2.4mpd in 1982,3.0 mpd in 1983
and 8.5 mpd in 1984 (AOF&G 1981a,1982a;Barrett et a1.1984,
1985)•
(iv)Spawning Locations
Almost all sockeye salmon in the Talkeetna-to-oevi1 canyon
reach (RM 98.6-152)spawn in slough habitat (Barrett et a1.
1984,1985).Relatively few sockeye spawn in the mainstem and
tributaries.One main channel spawning site was identified
during the 1983 survey and seven sites were located in 1984
37
-
(Barrett et al.1984,1985).The 1983 mainstem site (RM
138.6-138.9)was used by eleven spawning sockeye on September
15.Mainstem spawning sites were located between RM 131 and
142 in 1984.The peak count for all seven sites was 33 fish
(Barrett et;:;l.1985).About 50 percent of these fish were
spawning in side Channel 11 (RM 134.5-135.3)(Barrett et al.
1985)•six sockeye were observed in streams during the 1981
through 1984 surveys.However,all six were considering
milling fish that did not spawn in streams (ADF&G 1981a, 1982a,
Barrett et al.1984).In 1984,13 sockeye were observed in
streams (Barrett et al.1985).
During slough spawning surveys in 1981 through 1984,sockeye
were observed in 23 sloughs upstream of RM 98.6 (Table 7).
Three sloughs contained most of the fish in all four years.
Sloughs 8A,11 and 21·accounted for 89 percent of the peak
counts in 1981,95 percent in 1982,92 percent in 1983 and 88
percent in 1984 (Table 7).
The peak of the sockeye spawning activity in sloughs occurred
between the last week of August and the end of September in all
four years (ADF&G 1981a,1982a;Barrett et al.1984,1985).A
portion (24-44 percent)of the sockeye salmon monitored in
sloughs in 1983 and 1984 did not spawn in the slough of first
recorded entry (Barrett et al.1984,1985).These fish
suffered mortality from either bear predation or stranding,or
departed the slough and presumably spawned elsewhere (Barrett
et al.1984).
Total slough escapement of sockeye salmon upstream of RM 98.6
was estimated by calculati"1g the total fish days in slough
habitat and then dividing by the average slough life (Barrett
et al.1984,1985).The total slough escapement was about
2,200 fish in 1981,1,500 fish in 1982,1,100 fish in 1983 and
2,200 fish in 1984 (Table 8).
38
Table 7.Second-run sockeye salmon peak survey eotmts in sloughs upstream of
RM 98.6,1981-1984 •
.....
Four-Year
'"""Slough River Mile 1981 1982 1983 1984 Average
f~1 99.6 0 0 0 10 3
2 100.2 0 0 0 7 2
3B 101.4 1 0 5 20 7
3A 101.9 7 0 0 11 5
~It,5 107.6 0 0 0 1 0
6A 112.3 1 0 0 0 0
8 113.7 0 0 0 2 1
.-8e 121.9 0 2 0 0 1
8B 122.2 0 5 0 1 2
Moose 123.5 0 8 22 8 10
"....SA 125.1 177 68 66 /128 110
B 126.3 0 8 2 9 5
9 128.3 10 5 2 6 6
9B 129.2 81 1 0 7 22.-9A 133.8 2 1 1 0 1
10 133.8 0 0 1 0 0
11 135.3 893 456 248 I 564 540
!-15 137.2 0 0 0 1 0
17 138.9 6 0 6 16 7
19 139.7 23 0 5 11 10
20 140.1 2 0 0 0 1
21 141.1 38 53 197 122 103
22 144.5 0 0 0 2 1
Total 1,241 607 555 926 832 (1)
Source:ADF&G 1981a,1982a;Barrett et al.1984,1985
(1)Four-year average of totals
r-',
39
Table 8.Second-ron sockeye salmon total slough escapement upstream of
RM 98.6,1981-1984.
~Four-Year
Slough River Mile 1981 1982 1983 1984 Average
""'"
1 99.6 0 0 0 26 7
2 100.2 0 0 0 18 5
r-"3B 101.4 0 0 10 36 12
3A 101.9 13 0 0 29 11
5 107.6 0 0 0 3 1.....·8 113.7 0 0 0 5 1
8e 121.9 0 5 0 0 1
8B 122.2 0 13 0 0 3
Moose 123.5 0 20 31 0 13
SA 125.1 195 131 130 532 247
B 126.3 0 20 10 23 13
9 128.3 18 13 0 16 12
I"""9B 129.2 212 0 0 18 58
9A 133.8 4 0 0 0 1
11 135.3 1,620 1,199 564 11.,280 1,166
1""".15 137.2 0 0 0 3 1
17 138.9 11 0 11 26 12
19 139.7 42 0 10 29 20
~21 141.1 63 87 294 154 150
22 144.5 0 0 0 5 1
Total 2,178 1,488 1,060 2,203 1,732 (1)
..,..
.....
Source:Barrett et ale 1984,1985
(1)Four-year average of totals
40
-
(v)Access
The upstream passage of salmon into sloughs and side channels
is dependent primarily on water depth and length of the passage
reaches that are restrictive to the upstream movement of fish
(Sautner et al.1984).Hydraulic velocity barriers do not
exist in the Talkeetna-to-Oevil Canyon reach (RM 98.6-152)
(Trihey 1982)•The mainstem discharge level directly
influences passage into sloughs because of its influence on
backwater at the mouths of sloughs and breaching at the
upstream (head)ends of them.Under low mainstem discharge
conditions (unbreached),the backwater at the mouths of sloughs
and side channels may not be of sufficient depth to allow
successful passage.As mainstem discharge increases,the
backwater area generally increases in depth and extends its
length upstream,which increases the depths within those
reaches affected by the backwater.The elimination of passage
restrictions within a reach by backwater inundation oontinues
in the upstream direction with increasing mainstem discharge.
When breaching ocours,depths become adequate for passage at
all passage reaches in most sloughs and side channels (Sautner
et al.1984).
Mainstem discharge levels in the Susitna River at Gold Creek
(RM 136.7)commonly range between 20,000 and 30,000 cfs during
June,July and August when adult salmon are migrating upstream
and 15,ono to 20,000 cfs during peak spawning periods (20
August to 20 September)(Sautner et al.1984).Passage into
sloughs varies considerably at a mainstem discharge level
because of the diversity in the morphology of individual
sloughs.Breaching of most sloughs in the Talke~tna-to-Oevil
Canyon reach (RM 98.6-152)occurs at relatively high mainstem
discharges (19,000 to 42,000 cfs)(Sautner et al.1984).
During the August 20 to September 20 period,mainstem discharge
at Gold Creek is less than 15,000 cfs 50 percent of the time
(Sautner et al.1984).Therefore,passage into sloughs and
41
~I
-
-
~.
-
side channels is often controlled by the backwater at the
slough mouth and the local flow from groundwater and runoff
sources.
Sloughs 8A,11 and 21 have a.:.counted for over 90 percent of the
sockeye salmon total peak counts in slough habitat (Table 7).
At Slough 8A,successful passage conditions occur for all
passage reaches when the northeast channel is overtopped at
33,000 cfs (Sautner et ale 1984).When the northwest channel
breaches (27,000 cfs),the three lowermost reaches have
successful passage conditions (Sautner et ale 1984).At lower
mainstem discharges,Passage Reaches I and II have successful
passage conditions due to backwater effects at mainstem
discharges of 10,600 and 15,600 cfs,respectively (sautner et
ale 1984).Slough 11 is overtopped at a higher than normal
mainstem discharge of 42,000 cfs (Sautner et ale 1984).Below
breaching flows,the first three passage reaches have
successful passage conditions at 16,200,33,200 and 39,600 cfs,
respectively (Sautner et ale 1984).None of.the passage
reaches in Slough 21 are influenced by backwater below the
breaching discharge of the left fork (25,000 cfs)(Sautner et
ale 1984).The local flows required for successful passage
conditions at specific passage reaches have not been
determined.Analyses are currently being done to determine
these values in sloughs 8A,9,9A,11 and 21.
(vi)Fecundity and Sex Ratio
The mean fecundity for Susitna River second-run sockeye is
3,350 eggs per female (Barrett et ale 1984).This estimated
fecundity is derived from the regression analysis of fecundity
as a function of length and from the mean length of sockeye
salmon measured at Sunshine station (Barrett et ale 1984).
The average egg retention from a sample of 56 sockeye salmon
was about 250 eggs per female in 1983 (Barrett et ale 1984).
42
-
......
-
-
Almost 80 percent of the carcasses had retained 25 or fewer
eggs,while only seven percent of the fish sampled had retained
more than 1,000 eggs each.In 1984,the average egg retention
was 64 eggs per female (Barrett et a1.1985).Most fish
examine '1 (67 of 76 females)had completely spawned (Barrett et
a1.1985).
The sex ratio (male to female)of second-run sockeye salmon in
the Susitna River was 1.0:1 in 1981,1.2:1 in 1982,1.2:1 in
1983 and 1.0:1 in 1984 (ADF&G 1981a,1982a;Barrett et a1 .
1984,1985).Sex ratios varied considerably between some
locations and years (Table 9).Sex ratios of sockeye salmon by
age were reported by ADF&G (ADF&G 1981a,1982a;Barrett et a1.
1984a,1985).Some males matured at an earlier age than
females.Most returning adult sockeye were four or five year
fish that had gone to sea after one year in freshwater (Barrett
et a1.1984,1985).
4.1.2 Chum Salmon
(i)Timing of Run
Chum salmon enter the Susitna River in late June to early July
and are numerous in the lower river at Yentna Station (RM 28,
TRM 04)by the third week of JUly (Barrett et a1.1984,1985).
The chum migration lasts about one month in the lower river,
with most fish passing Yentna·station by the third lIIeek of
August (Barrett et a1.1984,1985).The migration passes
Sunshine Station (RM 80)from the end of July to early
September.In the Ta1keetna-to-Devi1 Canyon reach (RM
98.F-152),the mi"gration begins about the end of July and
continues until the end of August.A summary of chum migration
timing in the Susitna River for 1981,1982 and 1983 is
presented in Figure 14.
43
Table 9.Sex ratios of second-nm sockeye at Flathom,SUsitna,Yentna,
SUnshine,Talkeetna and curry stations,1981-1984.
-
Sex ratio CM:Fl 1
~Location 1981 1982 1983 1984
Flathom station 1.5:1
~~RM 22
SUsitna station 0.9:1 1.0:1
RM 26
Yentna station 1.2:1.2.1:1 1.5:1 0.9:1
RM 28,TRM 04
sunshine station 1.0:1.0.9:1 0.9:1 0.6:1
RM 80
Talkeetna Station 0.6:1.1.3:1.1.6:1.0.6:1
RM 103
".-curry station 0.8:1 2.1:1 1.6:1.1.4:1
RM 1.20
-
,..,.
Source:ADF&G 1981a,1982a:Barrett et ale 1984,1985
1.Includes all aged am non-aged fish
Dashes indicate no su:r:vey
44
-1 I )J )J 1 1 1 J )1 1 j !1
CURRY
STATION"'
Ut83 I ';:i:':'rT"~;'?W :j:Wr }'::-':..~•
1882 1 rl':t:"&<'·<l I
""I p'i@t:::H/:::"I
CHUM SALMON
..."...,....
fl.'I'\Carel..H c';"'=!;!'H
/\
D%C-....t"'.n".OInIut.tlw,
Careh ,.t (tlorl Coleh p ••(tlo.t
.I'>
U1
TAlI(EETNA.
STATION
SUNSHINE..
STATION
,,~---------------------------------~--------
18131 EEl::i :'p 'lYE :T'yire ;:'it I I
18821 SilT?;0,1 ';':0 I
Ie,I'e:.E=!'i~IIlIMi:t:$ve#5M I
~------~~~-------------------------------,I~:!=I';"'.':""2\':":::';J.lmJ I "II
I III.'1:1 Jtk.[1:'.::.11812
,I i ttYi-':$~p 5)",'.1':;J ':.resg I ,.1,
YENTNA
STATION"'
~----~-~-~---------------------------~------I J!if')::i t::'17;:1 F:';y:i!!:TIii:T>;::'1 I 1.1'
H':/;:<;:':*1 ;j:e!:·,:,;:~?:*'''12
I hi:f?:I !':W:,:::C~=:9::::;':;"3 I ...,
I
8/21
I I I I I I r ,I I I ,--I
7/1 7/11 812 -1/18 "30 .,t3
DATE
I
IIZ7
MIGRATIONAL TIMING OF CHUM SALMON BASED ON FISHWHEEL CATCH PER UNIT EFFORT AT SELECTED
LOCATIONS ON THE SUSITNA RIVER IN 1981,1982 AND 1983.(SOURCE:BARRETT et aL1984)
•ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 14
Woodward·Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
-
-
-
....
Chum salmon migration timing is likely influenced by river
discharge (Barrett et a1.1984).Peak river discharge levels
of 100,000 cfs or greater at Sunshine station in 1981 and 1983
coincided with reduced fishwhee1 catches at Sunshine station
and apparently delayed upstream movement (F~.gure 15).
(ii)Escapement
For the last four years,the chum salmon minimum escapement in
the Susitna River has averaged 452,200 fish (Table 6).This
estimate is considered a minimum because it is based on the
summation of escapements at Sunshine and Yentna stations and
does not include escapements downstream of RM 80,excluding the
Yentna River (RM 28).In 1984,about 812,700 chum salmon
reached F1athorn station (RM 22)(Barrett et a1.1985).This
estimate can be considered the total Susitna River chum
escapement because spawning downstream of RM 22 is minimal
(Barrett et a1.1985).Most chum salmon spawn in the Talkeetna
River drainage (RM 97.1)(Barrett et a1.1985).
The annual chum salmon escapement for 1981 through 1984 aver-
aged 54,600 fish at Talkeetna station (RM 103)(Table 6),with
a range of 20,800 to 98,200 (Barrett et a1.1984,1985).These
escapements overestimate the number of fish that spawn upstream
of RM 103 because a significant portion of the escapement
returns downstream of Talkeetna station (Barrett et a1.1984,
1985)•In 1984,about 75 percent of the chum escapement to
Talkeetna Station returned downstream to spawn (Barrett et a1.
1985).If the 1984 escapement (98,200 fish)to Talkeetna
station is reduced to account for the milling factor,the
Ta1keetna-to-Devi1 Cany':m reach accounted for about 3 percent
of the 1984 total Susitna River chum escapement of 812,700 fish
(Barrett et a1.1985).The milling components of the chum
escapements to Talkeetna station were not estimated in 1981,
1982,or 1983.
46
I 1 1 1 1 1 ]1 J J )i i I ])J 1
1983
,1
f",I I
J.I I
"\ I \I I I \\),,,,
I,
\
\
\
\
"'."
.1I,
I :,,
"
I •
I ,
1
I
I
I~~\
\,
I
\
\
\,
\
\
(~,-"!"/.;"~
I.....
!:!
o
ao
40
ao
12
20,+100
14
.a
.a
.J......
J:
J
u...
II:
J:
J:..
e:
un.
1981
,,
I
I,
'......
I~
t \:,,
(
I,
I
I
,I
I•"'1I,
I \
I,
I \
I \
I
I,
\.\I,.
"V
.AlI.Y
l..
I
I
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I,
I,
I,,
I
\
V"'--,,
\V
I
I
\ I
\ I,,,,
\','V
iii
~
I.....
!:!
o
.'\10
70
4
II
110
130
110
10-.1-1110
~
u...
.J......
J:
J
~.,
J:
%..
oJ:>.
-..J
70
HARZA-EBASCO
SUSITNA JOINT VENTURE
Woodward.Clyde Consultants
and
ENTRIX,INC.
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 15
....WHEEL CATCH IFC)
DISCHARGE lOt
COMPARISON OF CHUM SALMON FISHWHEEL CATCH AND
-MAINSTEM DISCHARGE AT SUNSHINE STATION (RM 80),
1981-1983.
tI
un.
1982
I,
I'
I ~
'''"',.
.."-.....,I "
'OJ \....",'
"
I,'.,,
I,
I I,\
: I ,l,',
I I II
I \ ,
I II:~
I•
I ,,'.,'.,'A'~;"\./\..,-~~;
I ,,,
\ 1'.'
iii
8
!'!
o
o
3
411
36
lIO
II
u
16
10
110
6lI
40
~
.J......
J:
J
u..
a:
J:
J:..
(iii)Migration Rate
,~
"""
~-
Tagged chum salmon migrated between Sunshine Station (RM 80)
and Talkeetna Station (RM 103)at an average rate of travel of
4.1 miles per day (mpd)in 1981,4.9 mpd in 1982,3.8 mpd in
1983 and 5.8 mpd in 1984 (Barrett et ale 1984,1985).Chum
salmon migrated between Talkeetna station and curry station (RM
120)at the following rates:4.5 mpd in 1981,7.7 mpd in 1982,
6.3 mpd in 1983 and 8.5 mpd in 1984 (Bar't'ett et ale 1984,
1985).
(iv)spawning Locations
Most chum salmon spawning in the Talkeetna-to-Oevil Canyon
reach occurs in either slough or tributary stream habitats.In
1983 peak index counts in stream and slough habitats were about
equal,while in 1981,1982 and 1984 counts were higher in
sloughs (Table 10)~
Chum salmon peak index counts in sloughs upstream o·f RM 98.6
were:2,596 fish in 1981,2,244 fish in 1982,1,467 fish in
1983 and 7,556 fish in 1984 (Table 11).Ten sloughs were
occupied by spawning chum salmon in all four years (Table 11).
Five of the ten (sloughs 21,11,8A,9A and 9)accounted for
over 70 percent of the chum salmon counted (Table 11).
Total slough escapements of chum salmon in sloughs upstream of
RM 98.6 were estimated by dividing the total fish days in
slough habitat by the average slough life of chum salmon
(Barrett et ale 1984,1985).The total slough escapement was
about 4,500 fish in 1981,5,100 fish in 1982,2,950 fish in
1983 and 14,650 fish in 1984 (Table 12).
Chum salmon peak index counts in streams upstream of RM 98.6
were:241 fish in 1981,1,737 fish in 1982,1,500 fish in 1983
and 3,814 fish in 1984 (Table 13).In 1981,Indian River,
48
Table 10.Chum salmon peak index COlmts by habitat type upstream of RM 98.6,
~1981-1984.
Source:ADF&G 1981a,1982a;Barrett et al.1984,1985
1 Includes main channel and side channel habitats
2 Includes upland slough and side slough habitats
3 Four-year average of totals
-
49
Table 11.Chum salmon peak index counts in sloughs upstream of RM 98.6,
1981-84.
Four-Year
Slough River Mile 1981 1982 1983 1984 Average
~
1 99.6 6 0 0 12 5
2 100.2 27 0 49 129 51
3B 101.4 0 0 3 56 15
3A 101.9 0 0 0 17 4
4 105.2 0 0 0 0 0
5 107.6 0 2 1 0 1
6 108.2 0 0 0 0 0
6A 112.3 11 2 6 0 5
7 113.2 0 0 0 0 0
8 113.7 302 0 0 65 92
Bl1shrod 117.8 0 0 0 90 23
80 121.8 0 23 1 49 188e121.9 0 48 4 121 43
8B 122.2 1 80 104 400 146
Moose 123.5 1.67 23 68 76 84
AI 124.6 140 0 77 111 82
A 124.7 34 0 2 2 10
SA 125.1 620 336 37 917 478-B 126.3 0 58 7 108 43
9 128.3 260 300 169 350 270
9B 129.2 90 5 0 73 42
9A 133.8 182 118 105 303 177
10 133.8 0 2 1 36 10
11 135.3 411 459 238 1,586 674
12 135.4 0 0 0 0 0
13 135.9 4 0 4 22 8
14 135.9 0 0 0 1 0
15 137.2 1 1 2 100 26,-16 137.3 3 0 0 15 5
17 138.9 38 21 90 66 54
18 139.1 0 0 0 11 3
19 139.7 3 '0 3 45 13
20 140.0 14 30 63 280 97
21 141.1 274 736 319 2,354 921
22 144.5 0 0 114 151 66
,~21A 145.3 8 0 0 10 5
Total 2,596 2,244 1.,467 7,556
Source:ADF&G 1981a,1982a~Barrett et aL 1.984,1985
1 Four-year average of totals
50
Table 12.,Chtnn sa1Inon total slough escapement upstream of RM 98.6,1981-1984 .
.-Four-Year
Slough River Mile 1981 1982 1983 1984 Average
-1 99.6 10 0 0 46 14
2 100.2 43 0 96 188 82
3B 101.4 0 0 0 109 27
6A 112.3 19 5 0 0 6
8 113.7 695 0 0 217 228
Bushrod 117.8 0 0 0 161 40
80 121.8 0 53 0 60 28
8e 121.9 0 108 8 207 81
8B 122.2 0 99 261 860 305
Moose 123.5 222 59 86 284 163
Al 124.6 200 0 155 217 143
A 124.7 81 0 4 8 23
8A 125.1 480 1,062 112 2,383 1,009
B 126.3 0 104 14 168 72
9 128.3 368 603 430 304 426
9B 129.2 277 12 0 132 105
10 133.8 0 0 0 90 23
9A 133.8 140 86 231 528 246
11 135.3 1,119 1,078 674 G,418 1,572
F 13 135.9 7 0 8 16 8
14 135.9 0 0 0 4 1
15 137.2 0 0 4 67 18
16 137.3 5 0 0 20 6
17 138.9 135 23 166 204 132
18 139.1 0 0 0 42 11
19 139.7 5 0 6 102 28
~20 140.0 24 28 103 329 121
21 141.1 657 1,737 481 4,245 1,780
22 144.5 0 0 105 187 73
21A 145.3 14 0 0 38 13
~
Total 4,501 5,057 2,944 14,634 6,7841
Source:Barrett et a1.1984,1985
1 Four-year average of totals
--51
""'"
Table 13.Chum salmon peak index counts in streams upstream of RM 98.6,
1981-84 ..
52
-Fourth of July Creek and Lane Creek accounted for 85 percent of
the 241 chum salmon counted during peak surveys (Table 13).In
1982,1983 and 1984 over 95 percent of the chum salmon counted
in streams were observed in Indian River,Fourth of July Creek
and Portage Creek.
Less than 10 percent of the peak survey counts of chum salmon
used mainstem spawning areas in 1981 through 1984 (Table 10).
Peak counts at mainstem spawning sites y 7 ere:16 fish in 1981,
550 fish in 1982,219 fish in 1983 and 1,266 fish in 1984
(Table 10).During 1981 through 1984,38 mainstem spawning
sites were identified.Most of these were sites located during
1984.Three sites were used in three or more of the four years
(Table 14).
Generally,the peak spawning activity of chum salmon occurred
during the last week of August in streams and the first two
weeks of September in sloughs and mainstem spawning sites in
1981 through 1984 (ADF&G 1981a,1982a;Barrett I et al.1984,
-1985)•
(v)Access
Access and passage of salmon into tributaries is controlled by
conditions at stream mouths.As the stage in the mainstem
decreases,the tributary mouths may become perched above the
river.That is,steep deltas may form.If these steep deltas
were to remain under low mainstem conditions ,the upstream
passage of fish into tributaries could be inhibited.Based on
the analyses by R&M Consultants (1982),Trihey (1983)and
Harza-Ebasco (1984),most tributaries in the Talkeetna-to-Devil
Canyon reach will adjust to lower mainstem flows without
detrimental effects on fish access.
Access and passage conditions into selected sloughs for chum
salmon are similar to the conditions described for sockeye
.-53
Table 14.Chtnn salmon peak spawner counts in mainstem habitats upstream of
RM 98.6,1981-1984.
'"""
I..ocation 1 1981 1982 1983 1984
River Mile Bank
100.9 R 89
110.1 L 4
114.0 C 46
114.6 R 10 69,....llS.O R 15
115.1 R 20 50
118.9 L 17 21
119.1 L 15
~,119.4 L 2
121.6 R 2
124.0 L 18
.......124.9 C 8
128.3 R 73
128.6 R 10 77
129.2 R 2
129.8 R 5 18
130.0 R 5
130.5 R 3 36
131.1 L 3 81
131.3 L 12 4 57
131.5 L 102
131.7 L 20
131.8 L 18
134.6 L 2
135.1 R 8
~135.2 R 40
136.1 R 6 50 110 131
136.3 R 31
136.8 R 12 6
137.4 R 25
138.7 L 36
""""139.0 L 16 56 87
140.5 R 6
140.8 R 2
141.4 R 45
~141.6 R 1
143.3 L 22 45
148.2 C 400
Total 14 550 219 1,266
1 L =Left,R =Right,C =Center as facing upstream.
Source:Barrett et ale 1984,1985
54
salmon in section 4.1.1,v.Sloughs 8A,9,9A,11 and 21 have
accounted for over two-thirds of the total peak counts of chum
salmon in slough habitats during 1981 through 1984 (Table 11).
Breaching and backwater effects at sloughs 8A,11 and 21 have
been mentioned previously (Section 4.1.1).At Slough 9,
breaching occurs at 16,000 cfs (Sautner et ale 1984).Below
the breaching discharge,Passage Reach I has successful passage
conditions at a discharge less than 12,000 cfs (Sautner et al.
1984).The breaching and backwater effects on passage condi-
tions have not been evaluated at Slough 9A (Sautner et al.
1984).
(vi)Fecundity and Sex Ratio
I"""
I
-
-
The mean fecundity for Susitna River chum salmon is 2,850 eggs
per female (Barrett et al.1984).This estimated fecundity is
derived from the regression analysis of fecundity as a function
of length and from the mean length of females sampled at
Sunshine station (Barrett et al.1984).
The egg retention of chum salmon was estimated in 1983 from
sampling 229 female carcasses in 12 sloughs and one main
channel spawning site between river miles 98.6 and 161 (Barrett
et al.1984).The median retention was about 114 eggs per
female (Barrett et al.1984).Almost 75 percent of the
carcasses had retained 25 or fewer eggs,while less than four
percent of the fish sampled had retained more than 1,000 eggs
each (Barrett et al.1984).In 1984,the average egg retention
for 215 fish was 463 eggs per female (Barrett et al.1985).
Over 75 percent of the fish sampled had completed spawning
(Barrett et al.1985).
The sex ratio (male to female)of chum salmon in the Susitna
River was 1.0:1 in 1981,1.1:1 in 1982,1.2:1 in 1983 and 1.2:1
in 1984 (ADF&G 1981a,1982a;Barrett et al.1984,1985).Sex
ratios varied between locations and years (Table 15).Sex
55
~,
,-..
Table 15.Sex ratios of chum saJ1non at Flathom,susitna,Yet1tna.,sunshine,
Talkeetna.and Curry stations,1981-1984.
IDeation;Sex ratio (M:F)1
River Mile 1981 1982 1983 1984
Flathom station 1.1:1
RM 22
susitna station 0.6:1 0.7:1
RM 26
yentna station 1.0:1 1.3:1 1.3:1 0.7:1
RM 28,n<M 04
sunshine station 0.8:1 1.0:1 1.0:1 1.1:1
RM 80
Talkeetna.station 1.3:1 1.9:1 1.5:1 1.4:1
RM 103
Curry Station 1.1:1 1.1:1 1.9:1 2.0:1
RM 120
Source:ADF&G 1981a,1982ai Barrett et a1.1984,1985
.1 Includes all aged and non-aged fish
Dashes i.n:1i.cate no survey
56
-
-
ratios by age are reported by ADF&G (ADF&G 1981a,1982a;
Barrett et ale 1984,1985).Most returning adult chum were
four or five year old fish that had gone to sea during their
first summer of life.
4.1.3 Coho Salmon
(i)Timing of Run
Coho salmon enter the Susitna River about mid-July and are
abundant in the lower river at Yentna station (RM 28,TRM 04)
from the third week of July until the third week of August
(Barrett et ale 1984,1985).Coho salmon are numerous in the
mainstem of the Talkeetna-to-Devil Canyon reach (RM 98.6-152)
from the last week of JUly to the first week of september
(Barrett et ale 1984,1985).A summary of coho migration
timing in the Susitna River for 1981,1982 and 1983 is
presented in Figure 16.
Coho salmon migration timing may be influenced by river
discharge (Barrett et ale 1984).In 1981 and 1983 discharge
levels of 100,000 cfs or greater at Sunshine Station coincided
with reduced fishwheel catches at Sunshine station and
apparently delayed the upstream migration of coho salmon
(Figure 17).
(ii)Escapement
The minimum coho salmon total escapement in the Susitna River
basin has averaged 63,400 fish for 1981 through 1984 (Table 6).
This estimate is based on the summation of escapements at
Sunshine and Yentna stations and does not include escapements
downstream of RM 80,exclUding the Yentna River (RM 28).In
1984,about 190,100 coho salmon reached Flathorn station (RM
22)(Barrett et ale 1985).This estimate is based on data from
the first year of monitoring at this location and does not
57
J )--1 i 1 j 1 j "}))}1 j i J
CURRY _
STATION
TALKEETNA
STATION -
l--Mij'Miiii;alli:;;;;,iiiiiRiiH 1911
~Wi_11812
~,;;;~11811
-----~----_..._---_-.-----------------
I lfSiiiiSiilm"iU."iWliiiiJ I 18 II
Hiiiijiijijlii;iiiiiii 11882
f---fMiiP;tijMit;UUi.:,I;;1iril '1881
COHO SALMON
"."1,"p .._.."',_\c.,~...
J4m;m~
/\
11%C-u'.lIwe ,D"y.Culllul.llwe
Co'c:h ptf fllo,'Co'c:h p.r Ellor'
111
OJ
SUNSHINE
STATION -
YENTNA _
STATION
----~----------~---------~~----------
I iiiifijliiiiiiiiijiiiijJ ,18 I 3
I 1:5;;_1'1;;;;:;:;;;1 ,1112
I S;:'iiM;m;;;iiI'';iiS 11181
~~-_...-----~_..._----------------------~--
~_~'if 11883
1-I;;;i;tiiJiliiiii'&'iiiiiit.,l I 18 I 2
I liP';;;;,I:;Piij(;:;;;i1i:kir/3 '188 I
I •T---11--1 J I I I
7/7 7/21 1/4 I/fl 8/1 •8/1&
I I
8/28
DATE
MIGRATIONAL TIMING OF COHO SALMON BASED ON FISH WHEEL CATCH PER UNIT EFFORT AT SELECTED
LOCATIONS ON THE SUSITNA RIVER IN 1981,1982 AND 1983.(SOURCE:BARRETT et 81.1984),
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 16
Woodward·Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
I )))J })1 j )}1l'!
J )l ))]
1983
\
\,,,,,
\
\,,
\
\,
'"'"'"
•11_no
1
t ,\
~I
II
It :"",\I
\.J
II
HARZA-EBASCO
SUSITNA JOINT·VENTURE
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
Woodward·Clyde Consultants
and
ENTRIX,INC.FIGURE 17
COMPARISON OF COHO SALMON FISHWHEEL CATCH AND
MAINSTEM DISCHARGE AT SUNSHINE STATION (RM 80),
1981-1983.
U"T.
t\,,
'\..,,,\
"\
'>J \....
-v
3 .....,00
1981 I
~
I ",.,'I I,'
10 J f '":
:::;
,.f..
' I
r
,
A 1 IN I I'"
IN
,\
%;;
0/,
1\i "
~0
,
"\
0 \
0:~
,%
\
i ~
,'"
en..
\
..
'..."
u "I
\
...
\.
\
1-40
\
\I
"
e.•
-,,,--.
~
IIlOT.
1982 I """WHEEL CATCH (FCI
DISCHAAGE (01 ..._------
AUG.
l
~1\,I)
II I I
J \, :
I \I I
I \,I
" I I
J'"I
,"I
\ I '
\ 1, I
, 1
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»"
,".....,,
\,...v ,,
, I
\I
'-'"
o
;;
~
!
'"..
B
o
!
iiig
o
~
"1'I',\
, I I,,~,
I , , \
, I,~", \I I,",
'J ,,\,,
I ,
I ,~\/\J ~B y
3+.0
4+110
.0
1I+130
1+70
II
Il
1I;"70
4-J-1I0
12"1..80
14+100
10
..J
IN...
%
~,
0:
%,
%
'"..
u...
0:
%
X
'"...
u...
..J...
IN
%
~
U1
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,,-
-
-
include escapements downstream of RM 22 (Barrett et ale 1985).
Most coho salmon in the Susitna River spawn in tributaries
downstream of RM 80 (Barrett et ale 1985).
The annual coho salmon escapement for 1981 through 1984
averaged 5,700 fish at Talkeetna station (RM 103)(Table 6),
with a range of 2,400 to 11,800 (Barrett et ale 1984,1985).
These escapements overestimate the number of fish that spawn
upstream of RM 103 because a significant number of fish return
downstream below Talkeetna station (Barrett et ale 1984,1985).
In 1984,approximately 75 percent of the coho escapement to
Talkeetna station returned downstream to spawn (Barrett et ale
1985)•If the 1984 escapement (11,800 fish)to Talkeetna
station is reduced to account for the milling component of the
run,the Talkeetna-to-Devil Canyon reach accounted for less
than 2 percent of the 1984 coho escapement to Flathorn Station
(Barrett et ale 1985).The milling co~ponents of the coho
escapements to Talkeetna station were not estimated in 1981,
1982,or 1983.
(iii)Migration Rate
Tagged coho salmon traveled from Sunshine station (RM 80)to
Talkeetna station (RM 103)at average rates of 4.0 miles per
day (mpd)in 1981,5.3 mpd in 1982,1.4 mpd in 1983 and 2.9 mpd
in 1984 (Barrett et ale 1984,1985).Coho salmon migrated
between Talkeetna station and CUrry station (RM 120)at an
average rate of:11.3 mpd in 1981,10.0 mpd in 1982,5.7 mpd in
1983 and 2.8 mpd in 1984 (Barrett et ale 1984,1985).
(iv)Spawning Locations
-..
Almost all coho salmon in the Talkeetna-to-Devil Canyon reach
(RM 98.6-152)spawn in tributaries (Barrett et ale 1984,1985).
only seven coho salmon have been observed spawning in mainstem
and slough habitats.In 1981,one fish was captured in the
60
mainstem at RM 129.2,in 1983 two coho salmon were observed
spawning in the mainstem at RM 131.1 and in 1984 two fish were
observed in the mainstem at RM 131.5.Two fish were observed
r>=.spawning in Slough 8A (RM 125 ~1)on October 2,1982 (ADF&G
1982a)•
Coho salmon peak index counts in tributary streams upstream of
RM 98.6 were:458 fish in 1981,633 fish in 1982,240 fish in
1983 and 1,434 fish in 1984 (Barrett et ale 1984,1985).
Twelve tributary streams upstream of RM 98.6 contained coho
salmon during index surveys in 1981 through 1984.Peak index
counts greater than 10 fish in all four years were recorded in:
Whiskers Creek,Chase Creek,Gash Creek,Lower McKenzie Creek,
Indian River and Portage Creek (Table 16).The two most
important tributary streams for coho spawning were:Gash Creek
and Indian River in 1981,Whiskers Creek and Lower McKenzie
Creek in 1982,Whiskers Creek and Indian River in 1983 and
Indian River and Whiskers Creek in 1984.
Coho spawning in tributary streams upstream of RM 98.6 usually
occurred between the last week of August and the first week of
October in 1981,1982,1983 and 1984 (ADF&G 1981a,1982a;
Barrett et ale 1984,1985).
(v)Access
conditions into tributaries for coho salmon are similar
conditions described for chum salmon (see Section
Passage
to the
4.1.2 ,v).
(vi)Fecundity and Sex Ratio
The mean fecundity of coho salmon in the Susitna River is 2,800
eggs per female (Barrett et ale 1985).This estimated
fecundity is derived from the regression analysis of fecundity
-61
Table 16.COho salmon peak in:iex COlll'lts in streams upstream of RM 98.6,
1981-1984.
-
-
Total 458 633 240 1,434
-
Source:ADF&G 1981a,1982a;Barrett et ale 1984,1985
1 Four-year average of totals
62
~.
.-
as a function of length and from the mean length of coho salmon
females sampled at Sunshine station (Barrett et al.1985).
The sex ratio (male to female)of coho salmon in the Susitna
River was 0.9:1 in 1981,1.4:1 in 1982,"1.3:1 in 1983 and 1.2:1
in 1984 (ADF&G 1981a,1982a;Barrett et al.1984,1985).The
sex ratios varied between years and sites (Table 17).Sex
ratios of coho salmon by age are reported by ADF&G (ADF&G
1981a,1982a;Barrett et al.198~,1985).Most returning adult
coho were three or four year old fish that"had gone to sea
after one or two years in freshwater (ADF&G 1981a,1982a;
Barrett et al.1984,1985).
4.1.4 Pink Salmon
(i)Timing of Run
Pink salmon enter the Susitna River in late June to early JUly
and are present in the lower river at Yentna Station (RM 28,
TRM 04)between the second week of July and the third week of
August (Barrett et al.1984,1985).In the Talkeetna-to-Devil
Canyon sub-basin (RM 98.6-152),the pink salmon migration in
the mainstem lasts about 4 weeks from the fourth week of July
to the third week of August (Barrett et al.1984,1985).A
summary of pink migration timing in the Susitna River for 1981,
1982 and 1983 is presented in Figure 18.
Upstream movements of pink salmon are likely influenced by peak
discharge levels.River discharge levels of 100,000 cfs or
greater at Sunshine Station coincided with reduced fishwheel
catches at Sunshine station i.1 1981 and 1983 and apparently
delayed the migrations (Figure 19).
63
Table 17.Sex ratios of coho salInon at Flathorn,susitna,Yeni::na,SUnshine 1
Talkeetna and CIJny stations,1981-1984.
Location,!Sex ratio &:F)l
""'"River Mile 1981 1982 1983 1984
F1athorn station 1.4:1
RM 22
susitna station 0.8:1 0.6:1
I~RM 26
Yentna station 0.9:1 2.4:1 2.3:1 0.8:1
,~RM 28,TRM 04
SUnshine Station 0.7:1 1.4:1 1.2:1 1.2:1
RM 80
""""
Talkeetna station 1.5:1 1.5:1 1.7:1 1.1:1
RM 103
,@l;;;1I,
CUr:ry station 2.0:1 1.3:1 2.0:1 1.1:1
RM 120
Source:ADF&G 1981a,1982a~Barrett et al.1984,1985
1 Includes all aged and non-aged fish
Dashes indicate no sw:vey
64
)»}~J .~....I ,..1
PI NK SALMON
)J -1 I l 11 j 1 I j j
CURRY
STATION •
M,dl....,a.
Rail"\Ca'e.
H;:4mi,':;::·I SiiG£H
/\
Oak CUMula'I.".0%CUMulatl."
Calc.par Elto,'Calcll ".,[110,1
t--IhJr;;,z,I;:,;.:&:;;;,;;;;,;.'1883
I .:;~mi;;t;1 1 1182
I ni5.i1t:Ki;;I;;;;j;:ii;",4;:>,<l~;.i;l 11881
TALKEETNA.
STATION
~---------~---------------------------------I ili,us,:t;,::;;:::;;';,,1 11183
I &iij :i.i'#i;;;~;:,1 1 1182
I--f::r;i;it£;.,fa';;;,;;:::;';;';;·'iiS;''I 1181
...-------------------------------------------
Cl\
U1
SUNSHINE •STATION
YENTNA..
STATION
I 1\!;·.*:wF·;Y;I··;.~,,;:;;;n;,:uy:c·,:::<1'I.~~·'-··~!f'!l,:~l ..,,.:i.,-..~!Z ···"'·"··:~·',~.~~·~A':(J;··[f;;'.I 8e I
I ~,>;FGi!iia 11882
If----------!.·g:..''I tit:;,?"ir:t':~'?;1 I.?::-.,!d:!IJ,!!:J~....I 881
~---------------~-----~----------------------1 I:,;'~;;;F!'~i::i:'I~i!;:~;;;Witi;~'~~!'ir 'r ;1 I.:,.:.;<:,»;.;~.,<..,..:J..~.-.«>..;;;;,;{$;.Li.;.1'"~(JdT,"j...J.'".18.3
I i3s:::;j··.·f:;.j;;i;rt,c,;;r1:!11182
I Ii:'::;;+',P:!;i;;-i;~;;;::,~;::~;'1::"1:,:iF,:~dm.«.'!'H I a 81t..-',.-.,."!,.·.·;·~.;;:·i ..t.;f··;/;;[=··:6:.<:,.,'."·f-,···>··~j·';"~{iM /,,·,:..N ,.,'..\;,:..,
I I
8/28
I
1/8
-I 1 1
1/18
, I
7/28
1
8/7
I .--,
8117
I ..
8/27
J
8/e
-1
DATE
MIGRATIONAL TIMING OF PINK SALMON BASED ON FISH WHEEL CATCH PER UNIT EFFORT AT SELECTED
LOCATIONS ON THE SUSITNA RIVER IN 1981,1982 AND 1983.(SOURCE:BARRETT et al.1984)
•ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 18
Woodward·Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT·VENTURE
1 1 1 1 1 j I 1 i 1 )1 1 1 1 J j )
HARZA-E8ASCO
SUSITNA JOINT -VENTURE
.....y
Woodward-Clyde Consultants
and
ENTRIX,INC.FIGURE 19
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
F!SHWHEEl CA rCM (FC)
DISCHARGE (Q)
COMPARISON OF PINK SALMON FISHWHEEL CATCH AND MAINSTEM
DISCHARGE AT SUNSHINE STATION (RM 80).1981-1983.
SlP1.AUG..u.y
\0......\80 4-+-\00 A
II
•'If,I I
1981 I I 1983,,I I
.-t ,'8O ,,,
I
'20
,I 3
,II,r.l'I ,;'\,,I ,,\I ~.\
I I I ,,'\,'"\,,,\:;\r,-\I ,::\I \...•I J I ..eo \...Ui ,,...0;\:E ,
\."",":E \/\~b I 1 ~b '--0
..'"0 \\,\~0 I I ,0 ,
Il eo ~I I \Il -,\/'.../
\I I
\:E !I '{\%iii!,'\~I \J%'"X '"'"...,I '"...
4 ~\I 0:40 IJ...I "'-.-a \,...-a
IJ \\IJ•,...\ I
...
V f\\
40 \'-...
•-t '.............I 1-.0
0\
.....y0\-
\80+\00 /,
1982
A
"
/ I
II
\40--1
I \
. I
I I A,I1O
I ,", I
I II
I ~,
I \:;\00 \,,-'v/\;,
\
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iii \I...
\I
\
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:E 'I
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,,....,,
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--"\..,,..
OJ
40 ~...a
IJ...
.0
'0
--
(ii)Escapement
Pink salmon have a two-year life cycle that results in two
genetically distinct stocks occurring in each stream.In the
Susitna Basin,the even-year runs are numerically dominant
(Barrett et a1.1984,1985).The odd-year pink salmon minimum
escapement in the Susitna River averaged 93,400 fish for 1981
and 1983,while the even-year m~n~mum escapement averaged
1,138,400 fish for 1982 and 1984 (Table 6).These estimates
are based on the summation of escapements at Yentna and
Sunshine Stations and do not include escapements downstream of
RM 80,excluding the Yentna River (RM 28).In 1984,·about
3,629,900 pink salmon reached F1athorn Station (RM 22)(Barrett
et a1.1985).This estimate is based on data from the first
year of monitoring at this location and does not include
escapements downstream of RM 22 (Barrett et a1.1985).Most
pink salmon in the Susitna River spawn downstream from the
Chulitna River confluence (RM 98.6)(Barrett et a1.1984,
1985).
The 1981 and 1983 odd-year pink salmon escapements averaged
5,900 fish annually at Talkeetna Station (RM 103)(Table 6),
with a range of 2,300 to 9,500 fish (Barrett et a1.1984,
1985)•The even-year escapement at Talkeetna station was
177,900 fish in 1982 and 73,000 fish in 1984 (Barrett et ale
1984,1985).The escapements at Talkeetna station overestimate
the number of fish that spawn upstream of RM 103 because a
significant number of fish return downstream below Talkeetna
station (Barrett et a1.1984,1985).In 1984,about 85 percent
of the pink escapement to Talkeetna station returned downstream
to spawn (Barrett et ale 1985).If the 1984 escapement
(177,900 fish)to Talkeetna station is reduced to account for
the milling factor,the Talkeetna-to-Devi1 Canyon reach
accounted for less than 1 percent of the 1984 pink escapement
to F1athorn station (Barrett et ale 1985).The milling
67
I~
components of the pink escapements.to Talkeetna station were
not estimated in 1981,1982,or 1983.
(iii)Migration Rate
Tagged pink salmon migrated from Sunshine station (RM 80)to
Talkeetna station (RM 103)at average rates of speed of 2.6
.miles per day (mpd)in 1981,7.4 mpd in 1982,5.9 mpd in 1983
and 5.9 mpd in 1984 (B~rrett et ale 1984,1985).The average
rates of travel increased between Talkeetna station and Curry
station (RM 120):6.0 mpd in 1981,10.0 mpd in 1982,7.1 mpd in
1983 and 9.4 mpd in 1984 (Barrett et ale 1984,1985).
(iv)Spawning Locations
The majority of pink salmon in the Talkeetna-to-Devil Canyon
reach (RM 98.6-152)spawn in tributaries (Barrett et ale 1984,
1985).Peak index counts for streams upstream of RM 98.6 were
378 fish in 1981,2,855 fish in 1982,1,329 fish in 1983 and
and 17,505 fish in 1984 (Table 18).In 1981,Lane Creek,Chase
Creek and Fourth of July Creek accounted for almost 95 percent
of the total peak counts of 378 fish.In 1982,when the pink
salmon escapement in the Susitna River was at an even-year
high,eight streams accounted for almost 93 percent of the
total count of 2,855 fish (Table 18).Indian River,Portage
Creek and Fourth of July Creek were the most important pink
salmon spawning streams in 1983;the three streams collectively
had a peak index count of 1,249 fish,or about 94 percent of
the total peak count of 1,329 fish.In 1984,85 percent of the
total peak count in streams was observed in Indian River,
Po~tage Creek,Fourth of July Creek,and Lower McKenzie Creek
(Barrett et a1.1985).Spawning activity in streams occurred
primarily during the first three weeks of August in all four
years (ADF&G 1981a,1982a;Barrett et a1.1984,1985).
68
Table 18.Pink salmon peak iniex counts in streams upstream of RM 98.6,
1981-1984.
River Odd-Year Even-Year
stream Mile 1981 1982 1983 1984 Average Average
Whiskers Creek 101.4 1 138 0 293 1 216
Chase Creek 106.9 38 107 6 438 22 273
Slash Creek 111.2 0 0 0 3 0 2
Gash Creek 111.6 0 0 0 6 0 3
lane Creek 113.6 291 640 28 1,184 160 912
Clyde Creek 113.8 0 a a 34 a 17
Maggot Creek 115.6 a a a 107 a 54
i"'""rawer McKenzie cr.116.2 a 23 17 585 9 304
McKenzie Creek 116.7 0 17 a 11 a 14
Little Portage cr•.117.7 .0 140 7 162 4 151
Frcmunda Creek 119.3
---
a a 0 40 0 20
;W!J;S D:::Iwr1Un.:2 Creek 119.4 a a a 6 a 3
Deadhorse Creek 120.8 a a a 337 0 169
Tulip Creek 120.9 a a a 8 a 4
I"""Fifth of JUly Cr.123.7 2 113 9 411 6 262
Skull Creek 124.7 8 12 1 121 5 67
Sherman Creek 130.8 6 24 a 48 1 3 36
Fourth of July cr.131.1 29 702 79 1,842 54 1,272
Gold Creek 136.7 0 11 7 82 4 47
Irxiian River 138.6 2 738 886 9,066 444 4,902
Jack I.ong cree1c 144.5 1 21 5 14 3 18
I'....Portage Creek 148.9 0 169 285 2,707 143 1,438
~1Iq
8541 10,1802Total3782,855 1,329 17,505
Source:Barrett et ale 1984,1985
1 Q:id-year aVeJ::age of totals
2 Even-year avE~ge of totals
69
Pink salmon were observed spawning in slough habitat in 1981,
1982 and 19~14.Total slough escapement upstream of RM 98.6 in
1981 was 38 fish in Slough 8 (Table 19).In 1982,total slough
escapement upstream of RM 98.6 was 297 fish in seven sloughs
~
(Table 19).Two of the seven sloughs (11 and 20)accounted for
over 80 percent of the escapement.No pink salmon were
observed spa.wning in sloughs in 1983;fish counted in slough
habitat duri.ng spawning surveys were considered milling fish
(Barrett et ale 1984).In 1984,the total pink salmon
escapement u.pstream of RM 98.6 was 647 fish (Table 19).The
three most important sloughs were:8A,11 and 20.In 1981 the
peak of spa\lming activity in sloughs occurred about the last
week of August,in 1982 it occurred during the first three.-
weeks of August and in 1984 it ranged from the second week of
August to the first week of September (ADF&G 1981a,1982a;
Barrett et ale 1985).
(v)Access
Passage conditions of salmon into sloughs and tributaries in
the Talkeetna-to-Devil Canyon reach have been discussed
previously (see sections 4.1.1,v and 4.1.2,V).
Sloughs 8A,11 and 20 appear to be important pink salmon
spawning areas (Table 19).Breaching and backwater effects at
Sloughs 8A and 11 have been discussed previously (see Section
4.1.1,v)•T:he upstream passage of salmon into Slough 20 is
apparently provided for by the local flow from Waterfall Creek
(Sautner et al.1984).Most pink salmon spawning occurs below
Waterfall Creek (Sautner et al.1984,1985).
(vi)Fecundity and Sex Ratio
The predicted fecundity for Susitna River pink salmon is about
1,350 eggs per female,which is based on the regression
-70
-
-
Table 19.Pink salmon total slough escapement upstream of RM 98.6,1981-1984.
Source:Barret±et al.1984,1985
1 Odd-year average of totals
2 Even-year ave~ge of totals
71
-
analysis of fecundity as a function of length and the me.an
length of all female pink salmon measured at Sunshine station
in 1983 (Barrett et ale 1984).
The sex ratio (male to female)of all pink salmon sampled in
the Susitna River was:0.8:1 in 1981,1.4:1 in 1982,0.9:1 in
1983 and 1.:3:1 in 1984 (ADF&G 1981a,1982a;Barrett et ale
1984,1985).Sex ratios at sampling locations in the Susitna
River for 15181 through 1984 are presented in Table 20.All
pink salmon returning to the susitna River are two year old
fish that wEmt to sea in their first summer of life (ADF&G
1981a,1982a;Barrett et ale 1984,1985).
4.1.5 Chinook Salmon
(i)Timing of Run
-
--
Chinook salml:>n enter the Susitna River in late May to early
June.In the lower river,most chinook (over 90 percent)have
migrated past susitna station (RM 26)by July 1 (ADF&G 1972).
The chinook s;almon migration at Sunshine station (RM 80)lasts
for about one month between early June and early July (Barrett
et ale 1984,1985).In the Talkeetna-to-Devil Canyon reach (RM
98.6-152),the chinook migration in the mainstem lasts for
about one ml:mth from mid-June to mid-July.A summary of
chinook migration timing in the Susitna River for 1981,1982
and 1983 is presented in Figure 20.
Chinook migrsLtion timing may be influenced by river discharge
(ADF&G 1982a).During 1981 and 1982 river discharge peaks
cnincided wi1:h reduced fishwheel catches at Sunshine Station
72
Table 20.Sex ratios of pink salmon at Flathom,SUsitna,Yentna,sunshine,
Talkeetna and curry stations,1981-1984.
r~
-Location;Sex ratio (M:F)
River Mile 1981 1982 1983 1984
Flathom Statilon 1.3:1
RM 22
.-SUsitna Statioll'l 0.4:1 0.9:1
RM 26
YentnaStation 0.8:1 1.0:1 0.9:1 1.2:1
"..,.
RM 28,T.RM 04
sunshine static:m 0.8:1 1.8:1 1.0:1 1.1:1
RM 80
Talkeetna station 1.2:1 1.6:1 0.8:1 1.1:1
,....RM 103
cuny station 0.8:1 1.5:1 1.0:1 1.6:1
RM 120
Source:Barre11:t et al.1984,1985
rashes Wicatl=no survey
,~
-73
J 1 1 ])}J ))·~J I J ]1 })
CHINOOK SALMON
Medlo/l P,••
,1Il0/l"\ C .te"~;mr:\:i:t"~r;:;fHIf"L":::~::'PtEtL"">·i 11982 J /\;.'::.:,,~'...>p<::::.&,..CufIIu'o"n 95%Cuftlula'h"_I ca,c"pI'Effo,t Catch per E"o,'Ik=!I=,..:';;)1:;:£::··:;;:,:i;:::;:";::~,i:1 11981
I I·;::e:f ~il:::::::;::::::::::;]'198 ;'
CURRY
STATION-
~--------~-----~-----------~---------
.......,.
TALKEETNA
STATION -
I l=,F,!·..51~tl·.YF:::H:';it;);gt4i;i:!!·\!t:5Y":.11983
J 1ft?"!;:"'¥::S;:ir:IF*Tiz,'}ttJ (1982
JI---~;::5::<r¥P:"t::,WCIl '.98 •
t---------------.....------------------...._--- ---
I l:dr';:::!t·,d;:·:,;,,!:::I 11982
SUNSHINE _'H::i:f;-(1:::.::.:52:::::·::;:d 11985
STATION
6/!5
I I I
6/19
"I I ••I I I
7/5 7117 7/31 8/14 8/28
DATE
MIGRATIONAL TIMING OF CHINOOK SALMON BASED ON FISH WHEEL CATCH PER UNIT EFFORT Ar SELECTED
LOCATIONS ON THE SUSITNA RIVER IN 1981,1982 AND 1983.(SOURCE:BARRETT et al.1984)
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 20
Woodward·Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT-VENTURE
..."
i'-'
--
-
-!
(Figure 21).However,in 1983 reduced fishwheel catches during
the chinook migration did not coincide with the peak river
discharges.The relationship of river discharge (above 100,000
cfs)with reduced fishwheel catches at Sunshine station is not
as clear for chinook ~almon as it is for sockeye,chum,coho
and pink salltnOn.
(ii)Escapement
The minimum chinook salmon escapement in the Susitna River in
1983 was approximately 125,000 fish.This estimate is based on
1983 chinook,stream surveys (Table 21)(Barrett et al.1984)
and the rellationship that a peak chinook survey count
represents a't most 52 percent of the total escapement (Neilsen
and Geen 1981).The total escapement derived by this method
should be viewed as an approximation because:(1)the 1983
surveys did not include all known chinook spawning streams in
the Susitna Basin (Barrett et al.1984)~(2)counts may not
represent pei:lk numbers as some streams were surveyed only once ~
and (3)the :t:'elationship that a peak survey count represents at
most 52 percent of the total escapement may not apply to
Susitna River chinook.In 1984,the chinook salmon total
escapement ilrl the Susitna River was about 250,000 fish (Barrett
et al.198!5).This estimate is based on the estimated
'escapement t.o Sunshine station (RM 80)of 121,700 fish and
stream surveys (Barrett et al.1985).
The annual chinook salmon escapements at Talkeetna station (RM
103)for 198:2 through 1984 averaged 16,700 fish (Table 6),with
a range of 10,900 to 24,800 (Barrett et a1.1984,1985).These
escapements overestimat~the number of fish that spawn upstream
of RM 103 because a significant part of the escapement returns
downstream bE!low Talkeetna station (Barrett et a1.1984,1985).
In 1984,
Talkeetna
about 45
station
percent
(RN 103)
of the chinook escapement to
returned downstream to spawn
75
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0\
1 J ))-j J J )J J )j J
..".
B I }J
7
1
8
~
III
III
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a
100
80
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go,d \I
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I V''''
",..
40 ~
o
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1982 ,~
I ,
/ I
, I,,
I I,V,
I''
/''../',.',.,
.....WHEEL CATCH (FC)
DISCHAJlOE (Q)
COMPARISON OF ~HINOOK SALMON FISHWHEEL CATCH AND
-MAINSTEM DISCHARGE AT SUNSHINE STATION (RM 80).
1981-1983.
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
.0
JU/E M.V FIGURE 21
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT·VENTURE
")-I'I -1 }))J "j J J -J }})B
Table 21.Chinook salmon peak survey escapement COl.U1ts of Susitna River streams by sub-basin from 1976 to 1984.
SUb-basin 1976 1977 1978 1979 1980 1981 1982 1983 1984
I.cMer susitna sub-basin1
Alexarrler Creek 5,412 9,246 5,854 6,215 a a 2,546e 3,755 4,620
Deshka River 21,693 39,642 24,639 27,385 a a 16,000d 19,237 16,892
Goose Creek 160 133 283 b a 262 140d 477 258
Kashwitna River (North Fork)203 336 362 4570 a 557 156d 297 1110
Little Willow creek 833 598 436 324 a 459 316d 1,042 b
Montana Creek 1,445 1,443 881 1,0940 a 814 887d 1,641 2,309
Sheep Creek 455 630 1,209 778 a 1,013 527 945 1,028
SUcker creek (Alexarrler creek)b b b b b b b
597 b
Willow creek 1,660 1,065 1,661 1,086 a 1,357 592d 777 2,789
WOlverine creek (Alexarrler creek)b b b b b b b 491 b
-..J SUbtotal 31,861 53,093 35,325 37,339 --4,462 21,164 29,259 28,007-..J
Yentna sub-basin2
camp creek (lake creek)b b b b b b b 1,050 b
canyon creek 44 135 b b b 84 b 575 b
lake creek 3,735 7,391 8,931 4,196 a a 3,577 7,075 a
Peters Creek 2,280 4,102 1,335 a a a a 2,272 a
Quartz Creek b 8 b b b 8 b b b
Red creek b 1,511 385 b b 749 b b b
sunflower creek (lake creek)b b b b b b b 2,250 b
Taladlulitna River 1,319 1,856 1,375 1,648 a 2,129 3,101 10,014 6,1380
SUbtotal 7,378 15,003 12,026 5,844 --2,970 6,678 23,236 6,138
Talkeetna-Qlulitna sub-basin3
Bunco Creek 112 136 a 58 a a
198d 523 51d
Byers Creek 53 69 a 28 a a 7 b 39
Chulitna River 124 229 62 a a a load b b
Chulitna River ,East Fork)112 168 59 a a a 119d b b
1 l 1 'j )J }1 J J J 1 ~)J J }]j
Table 21-(Continued)
SUb-basin 1976 1977 1978 1979 1980 1981 1982 1983 1984
Chulitna River (Middle·Fork)1,870 1,782 900 a a a
644d 3,846 4,1910ClearCreek(Chunilna)1,237 769 997 8640 a a 982.".806 1,520
Honolulu creek 24 36 13 37 a a 27u b b
Prairie creek 6,513 5,790 5,154 a a 1,900 3,844d 3,200e 9,000
Troublesome creek 92 95 a a a a 36 b b
SUbtotal 10,137 9,074 7,185 987 -1,900 5,957 8,375 14,801
Talkeetna-Devil Caffiron·sub-basin4
Chase creek 5 b b b b
b b 15 15 3
Cheechako ~b b b b b b
16 25 29
-..I Chinook ~b b b b b b 5 8 15(Xl
Devil creek b b b b b b
b 1 0
Fifth of ~uly creek b b b
b b b b b 17
Fog creek b b b b b b b b 2
Fourth of July creek b b b b b b
56 6 92
Gold creek b b b b b b 21 23 23
Indian River 537 393 114 285 a 422 1,053 1,193 1,456
Jack long creek b b b b b b 2 6 7
lane creek b b b b b
40 47 12 23
Portage creek 702 374 140 190 a 659 1,253 3,140 5,446
Whiskers creek b b b b b
b b 3 67
-
SUbtotal 1,239 767 254 475 -1,121 2,474 4,432 7,180
'IOTAL 50,615 77,937 54,790 44,645 10,453 36,273 65,302 56,126
~No total count due to high tw:bid water
Not counted
c Poor counting conditions
d Counts conducted after peak spawning
e Estimated peak spawning count
i RM 0-80,excluding the Yentna sub-basin
3 RM 28,Yentna River drainage
4 RM 80-98.6
5 RM 98.6-152
Above RM 152
-
(Barrett et.a1.1985).If the 1984 escapement (24,800)to
Talkeetna station is reduced to account for the milling factor,
the Ta1keetna-to-Devi1 Canyon reach accounted for about 5
percent of the 1984 Susitna River chinook escapement (Barrett
et a1.19185)•The milling components ,"Jf the chinook
escapements to Talkeetna station were not estimated in 1982 and
1983.Chin(Jok salmon escapements at Talkeetna station (and at
the other l;amp1ing locations in the susitnaRiver)were not
estimated ill 1981.
(iii)Migration Rate
-Tagged chinook salmon migrated between Sunshine station (RM 80)
and Ta1keetlna station (RM 103)at an average rate of travel of
2.1 miles pEar day (mpd)in 1982,1.8 mpd in 1983 and 3.3 mpd in
1984 (Barre't:t et a1.1984,1985).The average rate of travel
between Talkeetna station and Curry station (RM 120)was
,~
2.2 mpd in 1982,2.7 mpd in 1983 and 4.3 mpd in 1984 (Barrett
et a1.1984,1985).
(iv)Spawning Locations
In the Ta1keetna-to-Devi1 Canyon reach (RM 98.5-152)chinook
salmon spawn exclusively in tributaries (Barrett et a1.1984,
1985).Peak index counts in streams upstream of RM 98.6 were:
1,121 fish in 1981,2,474 fish in 1982,4,432 fish in 1983 and
7,180 fish in 1984 (Table 22).
The total l:::hinook salmon escapement to streams upstream of
RM 98.6 was estimated by the relationship that a maximum survey
count represents at most 52 percent of the total escapement
(Nielson and Geen 1981).Based on this method,the total
escapement 1:0 streams upstream of RM 98.6 was about 2,150 fish
in 1981,4,750 fish in 1982,8,500 fish in 1983 and 13,800 fish
in 1984.These escapements should be viewed as approximations
because:(1)in 1981 not all chinook salmon spawning streams
79
Table 22.Ch.iJnook sa1Jnon peak index counts in streams upstream of RM 98.6,
1981-1984.
~
River Four-Year
stream Mile 1981 1982 1983 1984 Average
Whiskers Creek 101.4 0 3 67
C1ase creek 106.9 15 15 3
lane Creek 113.6 40 47 12 23 31
"""Fifth of July Creek 123.7 3 0 17
Sherman Creek 130.8 3 0 0
Fourth of July Creek 131.0 56 6 92
Gold Creek 136.7 21 23 23
~Irdian River 138.6 422 1,053 1,193 1,456 1,031
Jack long creeJt 144.5 2 6 7
Portage creek 148.9 659 1,253 3,140 5,446 2,625
~.Oleechako Creek 152.5 16 25 29
Chinook creek 156.8 5 8 15
Devil creek 161.0 0 1 0
Fog creek 176.7 0 0 2
""'"
Jf~Total 1,121 2,474 4,432 7,180 3,8021
-Source:ADF&G 1981a,1982a;Barrett et ale 1984,1985
1 Four-year av'~ge of totals-Dashes indicaba no survey in 1981:no four-year average
,--
.-
80
....
--
.-..
were surveyed upstream of RM 98.6;and (2)more importantly,
the relationship that a peak count represents at most 52
percent of t.he total escapement may not be valid for Susitna
River chinook salmon.
Portage Creelk and Indian River are the two most important
tributary streams for chinook salmon spawning in the Susitna
River upstream of RM 98.6 (Barrett et ale 1984).The two
streams accounted for over 90 percent of the pee...k index counts
in 1981 through 1984 (Table 22).
The peak of the spawning activity in tributaries upstream of
RM 98.6 was between the last week of July and the first week of
August in 1981,1982 and 1983 (ADF&G 1981a,1982a,Barrett et
ale 1984).
(v)Access
Salmon are usually prevented from migrating upstream of Devil
Canyon (RM 152)because of the high water velocity.Low flows
in 1982,198:3 and 1984 allowed a few chinook salmon to pass
through Devil Canyon.In 1982,21 chinook salmon were observed
in two tribtltaries in upper Devil Canyon (ADF&G 1982a).In
1983,34 chinook salmon were observed in three tributaries in
upper Devil c:anyon (Table 22).In 1984,46 fish were observed
in three trihutaries in upper Devil Canyon (Table 22).
Trihey (1983)examined the hydraulic conditions supporting fish
passage into Indian River and Portage Creek,which are the two
most important streams for chinook spawning in the Talkeetna-
to-Devil Canyon sub-basin.Trihey I s analysis indicated that
passage of salmon into these two tributaries is not likely to
be impeded at:low mainstem discharge.
81
I~
t~,
(vi)Fecundity and Sex Ratio
The fecundity of chinook salmon has not been estimated in the
Susitna Rive~r,but is expected to be in the range of 4,200 to
13,600 eggs per female,as reported by Morrow (1980).
The sex ratio (male to female)of chinook salmon in the Susitna
River was 2.8:1 in 1981,1.4:1 in 1982,1.5:1 in 1983 and 1.1:1
in 1984 (ADlr&G 1981a,1982a;~arrett et al.1984,1985).Sex
ratios at s,amp1ing locations in the Susitna River for 1981
through 1984 are presented in Table 23.Sex ratios by age are
"-reported by ADF&G (ADF&G 1981a,1982a;Barrettet a1.1984,
1985).Most returning adult chinook salmon were five,six,or
seven year lold fish that had gone to sea after one year in
freshwater (,ADF&G 1981a,1982a;Barrett et al.198-4,1985).
4.2 INCUBATION
Salmon egg incubation in the middle reach (RM 98.,6-152)of the
Susitna River begins in July with chinook spawning in
tributaries and tributary mouths.This is followed by pink
salmon in mid-to late August and chum and sockeye in late
August to early September.Chum incubation begins about one
week earlier in the tributaries than in the sloughs.
Incubation of sockeye in sloughs begins at about the same time
as chum incubation.The last species to spawn are coho salmon,
which spawn almost exclusively in tributaries in September
(ADF&G 1981a,1982a;Barrett et al.1984,1985).
Successful i.ncubation and emergence is dependent on numerous
biological,chemical,and physical fact~rs.These factors
include disl:;olved oxygen,water temperature,surface water
discharge,and intragravel permeability (Reiser and Bjornn
82
Table 23.Sex ratios of chinook salmon at Yentna,sunshine,Talkeetna and
curry stations,1981-1984.
-
IDeation;Sex ratio CM:F)1
River Mile 1981 1982 1983 1984
~
yentna station 6.4:1 2.3:1 1.1:1
RM 28,TRM 04
sunshine statilDn 3.5:1 1.2:1 1.2:1 1.0:1
.~RM 80
Talkeetna station 2.7:1 2.3:1 2.4:1 1.1:1
RM 103
""'"
cuny station 1.9:1 1.5:1 1.4:1 1.2:1
RM 120
Source:Barrett et al.1984,1985
1 Includes all aged am non-aged fish
Dashes indicate no survey
-
I~
-
83
1979).Droughts,floods,freezing temperatures,super-
imposition 'of redds,and predators can also affect successful
incubation (McNeil 1969).The following sections discuss these
factors.The information is derived from studies on the
Susitna River and other locations.
4.2.1 Dissc)lved Oxygen
Dissolved oxygen is needed during incubation to
metabolic reactions.A literature review by Reiser
(1979),concluded that:
facilitate
and Bjornn
(1)Sa.c fry incubated in low and intermediate oxygen
cClncentrations were smaller and weaker than sac fry
reared at higher concentrations;
~,
(2)
(3)
LOlw oxygen concentrations in the early stages of
development may delay hatching,increase the
incidence of anomalies,or both;and
Low oxygen concentrations during the latter stages of
development may stimulate premature hatching.
Brannon (1965)found apparent differences in characteristics of
a1evins that had been incubated at oxygen concentrations
ranging froml 3.0 to 11.9 mg/1.Slowed development was evident
at low concentrations,but these fish eventually attained a
weight similar to those raised in higher concentrations by the
time they reached the fry stage.
The intragrclvel flow of water is important in assuring that
dissolved oxygen is made available to the inCUbating eggs and
that metabolic wastes are removed.Reiser and Bjornn (1979)
_recommend that the apparent velocity through the gravel should
84
-
-
-
be more than 20 em/hour,while Bell (1980)recommends a rate of
110 em/hour.Specific studies on intragravel flow have not
been performed in the Susitna River.
In studies em four SIO'lghs (8A,9,11,and 21)in the middle
river in April and May of 1983,ADF&G (1983a)found that mean
concentrations of intragravel dissolved oxygen were
consistently lower than mean concentrations for overlying
surface watE~rs.Means for intragravel concentrations ranged
from 4.6 to 8.5 mg/1,whereas the surface waters ranged from
9.1 to 11.2 mg/l.The lowest intragravel concentrations
occurred in Slough 8A and the highest in Slough 11.Assuming
that low dissolved oxygen levels occurred throughout the
incubation period (rather than only the April and May sampling
period),the:low concentrations in Slough 8A may have caused
some delay in chum and sockeye development.Diversion of cold
mainstem water through this slough as a result of an ice jam
may also hav'e contributed to delayed development.Development
at the othe:r three sloughs (9,11 and 21)foll'embryos and
a1evins was 'generally uniform.
McNeil and B,ai1ey (1975)recommend a dissolved oxygen threshold
of at least 6.0 mg/l for incubation,while Reiser and Bjornn
(1979)reco:mmend concentrations at or near saturation with
temporary reductions to 5.0 mg/l.In general,for the Susitna
River sloughs studied thus far,these recommendations are
usually met.The exception is the lower values found in
Slough 8A and some concentrations in Slough 9 (ADF&G 1983a).
Biochemical oxygen demand (BOD),reSUlting from excessive
amounts of organic material in the stream,can reduce dissolved
oxygen levels (Reiser and Bjornn 1979).BOD levels have not
been measured in theSusitna River.Under existing conditions,
dissolved oxygen levels remain at or greater than saturation in
the mainstem.Therefore,it is suspected that BOD is at low
levels.Habitats adjacent to the mainstem may have higher BOD
85
,..-
levels due to the high organic content of waters (e.g.,upland
sloughs),concentrations of dead post-spawned salmon (e.g.,in
side slough:s)or movement of water through the groundwater
system.
4.2.2 Tempe:rature
Temperature and salmon embryo development are strongly
interrelated,with higher temperatures resulting in more rapid
development.Development is also related to species,time of
egg deposition,and the temperature regime over the period of
incubation.In general,the lower and upper limits for
successful initial incubation of salmon embryos are 4.5 and
14.Soc (AE:IDC 1984)•Incubation can occur at lower
temperatures if the initial temperature is greater than
approximately 4.0 o C.This initial sensitivity to low
temperatures is apparently related to embryo developmental
phases because once the blastopore is closed on the developing
embryo,the sensitivity is reduced (Combs and Burrows 1957).
For most species in the Susitna River,the timing of egg
deposition j.s sUfficiently early in the season to avoid low
initial temperatures.The relationship between temperature and
embryo development is frequently measured in temperature units
(TUs).These are defined as the difference between the average
temperature and Ooc over 24 hours.For example,if eggs were
incubated at 7 0 C for 5 days,the accumulated TOrS would be 35.
If an embryo has accumulated 140 temperature units (the
approximate .developmental stage needed to achieve closing of
the blastopo,re),then it probably has passed the temperature-
sensitive st:age fCombs and Burrows 19S Pi).The peak spawning
activity for most salmon in the Ta1keetna-to-Devil Canyon reach
(RM 98.6-1S2)occurs prior to september 1.This is the case
for chinook and pink salmon (Barrett et al.1984).Chum and
sockeye sallnon overlap this period.However,they utilize
areas of groundwater upwelling in the mainstem and sloughs that
86
have tempersLtures throughout the winter that vary between 2 to
4 o C.Coho :salmon spawn late in the season.If they do not
spawn in upwelling areas (this is not known at the present
time),embryos theoretically do not accumulate sufficient
temperature units during this sensitive stage for proper
development.Additional studies would be needed to fUlly
understand if this species has different initial temperature
requirements for successful incubation.
studies by l\1angaard and Burger (1983)have shown that the time
to emergence.(complete yolk absorption)can vary considerably
at differen1t:temperatures.In laboratory tests at average
temperatures between 2.1 and 4.oOe,these authors found that
lower temperature would extend the time to complete yolk
absorption for Susitna River chum and sockeye eggs from 30 to
60 days.There are some weak compensatory mechanisms that tend
to counteract but not eliminate these differences.For
example,Dong (1981)suggested that the accumulation of one
temperature unit at low temperatures results dn a greater
amount of de~velopment than the accumulation of one temperature
unit at high temperature.However,this does not necessarily
provide enough compensation so that eggs incubated under
different rE~gimes hatch at the same time.This was evident
from the 30 to 60 day difference in complete yolk absorption
shown in the studies of Wangaard and Burger (1983).Embryos
incubated in colder water hatched at shorter lengths and
required fewer TO's for hatching.However,mean alevin length
at complete yolk absorption did not reveal the corresponding
differences.In summary,alevins at yolk absorption may be of
similar sizE~between two temperature ranges (in the 0 to 4 0 C
range),but alevins in the colder regi:t:e would take longer to
reach that stage while requiring fewer temperature units.
The temperature/time of emergence relationship has been studied
on the Skagit River in Washington (Graybill et al.1979).This
river has been affected by hydropower development for at least
87
.....
60 years.Present year-round water temperatures are generally
warmer by several degrees than pre-project temperatures (no
actual pre-proj ect temperatures have been recorded,however
modeling has established a likely pre-proj ect scenario).For
chinook salmon,the timing for spawning has not been notic,'ably
altered,at least through records that date back to 1948.
However,it appears that emergence timing of Skagit River
chinook has advanced by about one month.Pink salmon emergence
has advanced by about 4 to 11 weeks and chum salmon by 0 to 5
weeks.The implications of this advancement in the Skagit
River are not clear.
Numerous authors have speculated that an advancement of
emergence in any river system would not be specifically
patterned t(:>natural peak abundances in food organisms and
therefore wCluld not be advantageous to survival.Wangaard and
Burger's (1983)finding of a 30 to 60 day delay in chum salmon
emergence could mean that embryos incubated at the lower
temperatures would result in fish that are out pf phase with
the normal parr-smolt transformation (this transformation is
the salmonid life phase when they undergo a physiological
change so ~lat they can adapt to a saltwater environment)and
therefore,fish would not be viable.However,Wangaard and
Burger stat*~that the effect of early emergence on sockeye
salmon was unclear because sockeye rear for one to two years in
freshwater before they outmigrate.
To simplify the predictions for chum salmon incubation from
fertilization to emergence,AEIDC (1984)has developed a
nomograph with the variables of date of fertilization,average
incubation t,emr'erature,and date of emergence (Figure 22).If
the date of:spawning were known and an average incubation
temperature assumed,the date at which emergence would occur
could be predicted.This nomograph is useful for examining and
estimating potential changes in chum salmon incubation periods
under a wide range of temperature regimes in theSusitna River.
88
....Emergence
r(C)Dote
Spownirl9
....r"
....'"..June 10~Dote
I-1.0
"r"~June I-~
L5 May 20
July 20 -May 10
-2.0
,....-AUljIl -Mayl
I-2.5
AUljIlO -~i-April20
~3.0
AU1jI20 -I-3.5 April 10
"""~
...4.0 I-April I
Sept I -l-
I"'"10-4.5
I-
Sept 10 -5.0 I-March 2010-
~~5.5
Sept20 -I-6.0 I-March 10
I-6.5
I
.1-7.0
I-March IOctI-
Oct 10 -Feb 20
""'"....1..-
-FeblO
~
...J.,.
-Febl
-Jon 20
-Jon 10
~Jon I
CHUM SALMON SPAWN ING TIME VERSUS MEAN
INCUBATION TEMPERATURE NOMAGRAPH
(SOURCE:AEIDC 1984)
A LAS K A POW ERA U THO R tTY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 22
Woodward-Clyde Consultants
and
ENTRIX,INC.
89
HARZA-EBASCO
SUSITNA JOINT VENTURE
.pIIIllIil.
-
4.2.3 Substrate
Salmon require certain substrate characteristics for successful
spawning and incubation.The substrate must be capable of
allowing su,fficient flow to deliver dissolved oxygen to the
embryos and carry away metabolic wastes.It also must not
contain a high percentage of fine sediments which could cut off
the flow or prevent emergence of fry.As a general guideline,
Reiser and Bjornn (1979)recommend that the substrate used for
incubation should contain less than 25 percent by volume of
fines <6.4 mm.
Substrate also cannot be excessively large because adult salmon
generally l:ire unable to excavate'large rocks or solid
substrate.Instead,they require intermediate-sized gravels.
The substrate size used depends to some extent on the size and
species of fish and the substrate that is available to the
fish.Based on extensive field studies on the Susitna River by
Vincent-Lan~J et al.(1984),chum salmon in sloughs can utilize
substrates :between 1 in.and 10 in.in diameter.Sockeye in
sloughs alsc)utilize a similar size range of substrates.silt
is not used nor is sand.Chinook salmon spawn in tributaries
and most oj:ten utilize rubble (3-5 in.diameter)and cobble
(5-10 in.).Based on literature review and extrapolation from
other river systems,AD&FG (Vincent-Lang et al.1984)indicates
that pink salmon utilize substrates from small gravel
(1/8-1 in.:in diameter)to rubble (3-5 in.)with large gravel
(1-3 in.)bEdng preferred.Using a similar method of analysis,
Vincent-Lan~J et al.(1984)found that coho would mainly use
small (1/8 to 1 in.)to large (1-3 in.)gravel.
90
-
4.2.4 Streamflow
(i)High streamflow
During peric)ds of high streamflow,McNeil (1969)found that
disappearance of embryos due to streambed scouring often
exceeded 50 percent for chum and pink salmon eggs and alevins
in streams that he studied in southeast Alaska.On one
occasion,Mc:Neil recorded a loss that exce~ded 90 percent.
High flows c::an also cause deposition of fine sediment on the
redds,which can reduce permeability or entrap emerging fry
(Hale 1981).
A clear definition of the flows that result in loss is
ill-defined because moderately high flows may be beneficial in
assuring adequate interchange of intragravel and surface waters
and improving the oxygen supply to embryos (Reiser and Bjornn
1979)and,depending on conditions,may remove fine sediments.
In general,velocities should be less than those.that displace
spawning bed materials (Reiser and Bjornn 1979).
In the Susitna River and its tributaries,high streamflows and
bed material movement predominantly occur during the open water
season either due to high discharge from rain events or
ice/snow mel'ting.Increases in streamflow in side channels and
slough habitats can also occur during the ice covered period,
when ice jalns and staging cause overflows from the mainstem
(R&M Consultants 1984).The mainstem bed material appears to
be relatively stable compared to side channels and sloughs.
(ii)Low Streamflow
Once embryos have begun incubation,reductions in
lead to dessication of embryos,low oxygen
temperatures,or during cold weather,freezing
91
discharge can
levels,high
(Hale 1981).
-
McNeil (1969)found that freezing could be a cause of high
mortality ,:but that its occurrence was erratic in streams that
he studied in southeast Alaska.
Responses of incubating embryos and behavioral characteristics
of alevins t.o dewatering have been studied by Stober et ale
(1982)on the Skagit River,Washington.Using chinook,chum,
.coho,and pi.nk embryos,the authors found that various periods
of daily dewatering (with maintenance of humidity and
temperature)for up to 24 hrs per day in several substrate
types maintained prehatching survival for all species with a
decrease in post-hatching survival in direct relationship to
the length of daily dewaterings.Also,tolerance to single
dewatering events of various times decreased as development of
alevins progressed.Stober et ale (1982)qualified these
results to state that they should be used cautiously during
extrapolation to field conditions.Such extrapolation would
probably not be valid for the severe conditions (particularly
cold)that occur on the Susitna River.The I Skagit River
studies do point out,however,that alevins have some ability
to avoid severe conditions by moving through the gravel.
4.2.5 Superimposition
Superimposition can occur if salmon excavate existing redds
that were developed by previous spawners.In addition to
mechanical injury that can occur,existing embryos can be
removed from the redd,thus exposing them to light (which can
kill incubcLting embryos)and predators.Superimposition
becomes morE~prevalent when the density of spawning adults
increases.No specific studies have been undertaken to
determine effects of superimposition on the Susitna River.
However,because competition exists both within and between
salmon species in certain limited areas of spawning (e.g.,
sloughs),it is suspected that superimposition does occur.
92
-
~.
4 . 2. 6 Preda.tors on Live Eggs
Numerous spE~cies of predators can consume live eggs.McNeil
(1969)sUggE~sts that scu1pins (Cottus sp.)and possibly ·other
fish predatclrs may be involved.Potential predators,such as
rainbow tr011t and Dolly Varden,are present in the Susitna
River,but :no information is available on the effects of egg
and embryo predation.
4.3 JUVENIL~SALMON
4.3.1 Sockeye Salmon
(i)Emergen,ce
The emergence of sockeye salmon in the Ta1keetna-to-Devi1
Canyon reach (RM 98.6-152)occurs during the month of March
(ADF&G 1983b,c).In late April most sockeye juveniles of
age 0+have reached 33 mm in length.This obse!iVed emergence
timing is similar to the April to June emergence reported for
sockeye by M:orrow (1980)and Scott and Crossman (1973).
(ii)Seasonal Movements
In other river systems,sockeye usually spend one to two years
in lakes before going to sea (Morrow 1980,Scott and Crossman
1973)•How~~ver,in the Ta1keetna-to-Devi1 Canyon reach (RM
98.6-152),suitable lakes are not available for rearing
sockeye.Therefore,juvenile sockeye either rear in sloughs or
leave the Ta1keetna-to-Devi1 Canyon reach during their first
year of life (ADF&G 1984b).It is unknown if the age 0+
sockeye 1eav'ing this reach of river go directly out to sea as
smo1ts or mc)ve to rearing habitats in other sub-basins of the
Susitna river.If they do go directly to the ocean,their
survival is low (ADF&G 1981a,1982a;Barrett et a1.1984,
1985).
93
-
-
~.
For those :i uvenile sockeye that rear and overwinter in the
Talkeetna-t<:>-Devil Canyon reach,upland sloughs and side
sloughs are used most frequently.In 1982,over 90 percent of
the 1325 juvenile sockeye collected were in upland and side
slough habitats (ADF&G 1983b).Similarly,in 1983 densities
were highest in side slough and upland slough habitats (Schmidt
et ala 1984).In 1983 rearing sockeye were about equally
distributed between upland slough and side slough habitats
(Figure 23)"The most important upland slough was Slough 6A,
while Slough 11 was the most important side slough.
The importance of Slough 11 for rearing sockeye is likely due
to two fact:ors.First,Slough 11 is an important slough for
sockeye spa1llning,accounting for over 75 percent of the total
slough escapement for adult sockeye salmon in 1982 (Barrett et
ale 1984).And secondly,Slough 11 is breached only at high
discharges (over 42,000 cfs)(Sautner et ala 1984).This
condition provides more favorable rearing conditions than
breached sll:mghs.There have been decreased cat.ches in natal
side sloughs;after breaching transforms the side slough to side
channel habitat (Schmidt et ale 1984).
During July and August 1983 there was a redistribution of
juvenile sockeye from natal side slough habitat to upland
slough habitat (Schmidt et ale 1984).Slough 6A was the most
important upland slough for juvenile sockeye in 1982 and 1983
(ADF&G 1983b,Schn.idt et ale 1984).This slough has low water
velocity,clear water,adequate depth and abundant cover and is
quite different from the majority of sloughs in the Talkeetna-
to-Devil Canyon sub-basin (Schmidt et ale 1984).
Some juveni.le sockeye overwinter in the Talkeetna-to-Devil
Canyon sub-basin.This has been documented by winter sampling
and the downstream outmigrant trap catches of age 1+fish at
RM 103 (ADFStG 1983b,Schmidt et ale 1984).However,catches of
age 1+sockeye have been low (less than 1 percent of the
94
j J j -J )J 0)1 )1 J I -J J i ))1
f,lalnalem II
Seven Maln.'em
Situ Combinld
1.0
(JI
Nine Slough.
Combined
SIDE SLOUGHS
TRIBUTARI ES
MAINSTEM SI DE
CHANNELS
Slough ~
UPLAND SLOUGHS
COMBINED MACROHABITAT
TYPES
DISTRIBUTION OF JUVENILE SOCKEYE SALMON BY MACROHABIT AT TYPE ON THE SUSITNA RIVER
BETWEEN THE CHULITNA RIVER CONFLUENCE AND DEVIL CANYON,MAY THROUGH OCTOBER 1983.
PERCENTAGES ARE BASED ON MEAN CATCH PER CELL.(SOURCE:SCHMIDT et al.1984)
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 23
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SU81TNA JOINT ·VENTURE
..-
,~
outmigrant t:.rap catches),which indicates that this reach -of
river is I1l0t used extensively for overwintering.Age 1+
sockeye haVE!been observed in sloughs 9 and 11 (Schmidt et ale
1984)•
(iii)Food Habits
Juvenile soc:keye food habits were examined in July and August
1982 at sloughs 8A and 11 (ADF&G 19~3b).Fish were found to be
feeding primarily on chironomid larvae,pupae and adults.
However,do:minance of food items is based on numbers not
biomass or volume.Since chironomids are small,their
volumetric c:ontribution may be overemphasized by the numerical
method.Ele~ctivity indices suggested a positive selection for
chironomid larvae.Cladocerans and copepods were important
food items (::If juvenile sockeye in Slough 11 during August.A
variety of aquatic and terrestrial insects were also consumed •
(iv)outmig'ration Timing
Most juvenile sockeye salmon leave the Talkeetna-to-Devil
Canyon reach (RM 98.6-152)during their first year of life.
OVer 99 perc:ent (12,312)of the 12,395 juvenile sockeye caught
in outmigrant traps at RM 103 in 1983 were age 0+fish,while
only 83 fish were age 1+(Schmidt et ale 1984).If age 0+
sockeye go directly to the ocean their survival is low,because
less than (:me percent of returning adult sockeye at Curry
Station (RM 120)outmigrated as age 0+smolts (ADF&G 1982a).
The peak ol.:ltmigration of age 0+sockeye at RM 103 occurred
during ear~y July in 1982 and 1983 (ADF&G 1983b,Schmidt et ale
1984)(Fi~lre 24).The outmigration was monitored from
mid-June to mid-October in 1982 and from mid-May to the end of
August in 1983 (ADF&G 1983b,Schmidt et ale 1984).Catches of
age 0+socki3ye occurred throughout the sampling season.The
96
-10
9
O..f--r---r-r-.---r---r--r---r-...,..-r--..,.....~:::::;=;-~=;:=;:..c~I-l"'"1-.
III 23 211 2 7 12 11 2Z Z1 2 7 12 17 ZZ 21 6 11 16 21 26
I-MAY--I-I----JUNE I JUI.T-----!---A.UGUST----I
DATe::
8
-
CHUM SALMON FRY DAILY CATCH PER HOUR RECORDED AT THE
DOWNSTREAM MIGRANT TRAPS.MAY 18 THROUGH AUGUST 20,1983.
(SOURCE:SCHMIDT et at 1984)'
-
16.5
15.0
-
12.0
~10.5
o
::I:90
a:
\0,1
Q.
::I:
U
l-
e[
(,,)
0 I t I III,I I IIII28211217i!:2 21 2 21 26 31
~_"'AY I.JUNE:JULT :'UGUST
DATE
I'"~
SOCKEYE SALMON FRY DAILY CATCH PER HOUR RECORDEDAT
THE DOWNSTREAM MIGRANT TRAPS,MAY 1 a THROUGH AUGUST 3D,
1983.(SOURCE:SCHMIDT et al.1984)--------------------tALASKAPOWERAUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 24
Woodward-Clyde Consultants
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97
outmigration of age 1+sockeye occurred primarily during May
and June and was over by the end of July in 1982 and the end of
June in 1983.
Analyses wl:re done to compare 1983
outmigration catch rates at RM 103 with
(Schmidt et al.1984).The coefficient of
between mainstem discharge and outmigration
age 0+fish and 0.06 for age 1+fish.
(v)Size
j uvc.mile sockeye
mainstem discharge
determination (r2 )
rate was 0.12 for
-
-
The average size of outmigrating age 0+sockeye in 1982 at
RM 103 was 42 mm in late June and increased to 72 mm by early
October (ADF'&G 1983b).Age 1+sockeye in 1982 averaged 77 mm
in early June and 87 mIn in late JUly.In 1983 age 0+and 1+
fish were sc!parated by length analysis.In early May age 0+
sockeye werei less than 56 mIn,while age 1+fish were 56 mIn or
greater.Irl late June age 0+sockeye were less than 71 mIn,
while age 1+fish were 71 mm or greater (Schmidt et al.1984).
(vi)Population Estimates
In 1983 the population size of age 0+sockeye was estimated in
the Talkeetna-to-Devil Canyon reach (RM 98.6-152).Fry were
fin clipped and tagged with half-length coded wire tags at
sloughs 8A,11 dnd 21 and recaptured in downstream outmigrant
traps at RM 103.The population size was an estimated 560,000
fish using 11:he Peterson mark/recapture estimator and 575,000
fish using the Schaefer estimator (Schmidt et al.1984).
In 1983 sUZ"'tival estimates for egg to fry were calculated by
dividing the fry population estimate by the total potential egg
deposition.Survival from egg to fry was about 40.9 percent
using the Pe'terson estimate of population size and 42.0 percent
using the Schaefer estimate of population size (Schmidt et al.
1984)•
98
~-
.-
The high sU:l:'Vival rate (41-42 percent)for egg to outmigrant
for juvenilE!sockeye in the Talkeetna-to-Devil Canyon reach is
not comparable to survival estimates for egg to fry in other
studies (Sch~idt et ale 1984).The study in the Susitna River
covered a shorter period of tL'e (egg to age 0+sockeye),while
other studiE~s (Russell 1972 and Meehan 1966,cited in Schmidt
et ale 1984)reported survival estimates of 0.6 to 8.5 percent
from egg to age 1+or age 2+sockeye smo1ts.
4.3.2 Chum Salmon
(i)Emergen.ce
Chum salmon emergence in the Talkeetna-to-Devil Canyon reach
(RM 98.6-152)occurred during 1982 in late February and March
(ADF&G 1983b,c).By late April most juvenile chum were 35 mm
in length.Thus,it appears that chum salmon emergence occurs
in this reach of the Susitna River from February through April.
(ii)Seasonal Movements
After emergence chum salmon may outmigrate to the estuary in a
single night~if they are in systems close to the ocean (Scott
and Crossman 1973).However,in other situations the chum
outmigration may last for days or weeks (Morrow 1980).
Most juvenile chum in the Talkeetna-to-Devil Canyon reach
(RM 98.6-152)emerge by late April,while the peak outmigration
(at RM 103)does not occur until early June or early JUly
(ADF&G 19831b,c;Schmidt et a1.1984).This indicates that
juvenile chum from this reach t·-:the Susit'ba River may spend
one to threE~months rearing in freshwater.All juvenile chum
in the Susit~na River outmigrate as age 0+fish (ADF&G 1981a,b;
1982a;1983b;Barrett et ale 1984;Schmidt et ale 1984).
99
-
-
-
-
Almost all :iuvenile chum (over 90 percent)were distributed in
side slough and tributary habitats in the Talkeetna-to-Devil
Canyon reach during 1983 (Figure 25).These side sloughs and
tributaries were the same areas of adult chum spawning in 1982
(ADF&G 1982a).Slough 21 supported the highest density of
juveniles in side sloughs in 1983 while Indian River had the
highest den::3ity of juveniles in tributaries (Schmidt et ale
1984).
In early JtLne 1983 juvenile chum densities dropped in side
slough and tributary habitats and increased at side channels,
upland slouqhs and the downstream outmigrant traps at RM 103
(Schmidt et ale 1984).Most juvenile chum salmon leave the
Talkeetna-tol-Devil Canyon reach by mid-July (Figure 24).
(iii)Food Habits
The food habits of juvenile chum have not been examined in the
Susitna River.However,juvenile chum spend ,one to three
months rearing in the Talkeetna-to-Devil Canyon reach
(RM 98.6-152)before outmigrating and can gain up to 27 mm in
length during this period (ADF&G 1983b).Morrow (1980)reports
that they :may feed on chironomids and cladocerans.Food
habi tat studies of juvenile chinook,coho and sockeye in the
Talkeetna-tel-Devil Canyon sub-basin indicate that chironomids
comprised a significant portion of the diet for these three
species (ADF&G 1983b).It is expected that juvenile chum al~o
feed on chironomids in this reach of river.other food items
may be important.
(vi)OU'~miC[ration Timing
All juvenilE!chum salmon in the Susitna River outmigrate to
ocean in thleir first year of life.The outmigration from
Talkeetna-tel-Devil Canyon sub-basin was monitored by
downstream outmigrant traps (RM 103)from mid-June
100
the
the
the
to
1 )1 J J 1 )J J J I )I 1 1 .~)J )
SlouOh SA
SeYIn SlouOh,
Combined 2.5 -I.
Slough 8 6.5-'_
Slough 9 7.8"'_~
S loug h II
MAINSTEM SiDE CHANNEL
UPLAND SLOUGHS
Eleven
Moin'fem
S ifes Combined
9.5 ct•
W hllker.Creek
Slaugh
SlouOh 22
COMBINED
M ACROHABITAT
TYPES
SIDE SLOUGHS
TR IBUTARfES
Cho ..Cruk
Four Tributorl ..
Combined 2.0-'_
......
o
......
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
DISTRIBUTION OF JUVENILE CHUM SALMON BY MACROHABITAT TYPE ON THE SUSITNA RIVER BETWEEN THE
CHULITNA RIVER CONFLUENCE AND DEVIL CANYON,MAY THROUGH OCTOBER 1983.PERCENTAGES ARE BASED
ON MEAN CATCH PER CEll.(SOURCE:SCHMIDT et a!.1984)
FIGURE 25
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
,~
--
.-
mid-October in 1982 and mid-May to the end of August in 1983
(ADF&G 1983b,Schmidt et al.1984).In 1982,the peak
outmigration occurred on June 21,just three days after the
trap began fishing.Therefore,it is possible that the peak
outmigration occurred before June 18 in 1982.By mid-July 1982
almost 90 percent of the outmigrants (754 chum)had been
caught.No juvenile chum were caught at the trap after
mid-August in 1982 (ADF&G 1983b).In 1983 the outmigration
peaked between early June and early July.By mid-August all
juvenile chum had left the Talkeetna-to-Devil Canyon reach
(RM 98.6-152)(Figure 24).
Analyses were done ~o compare 1983 juvenile chum outmigration
catch rates with mainstem discharge (Schmidt et al.1984).
During mid-May to mid-July (this period accounted for over 98
percent of the catch at the downstream migrant traps)almost 80
percent of the variation in catch rates was accounted for by
mainstem discharge.The coefficient of determination (r2 )
between mainstem discharge and juvenile chum outmigration rates
was 0.79;r =0.89 (Schmidt et al.1984).
(v)Size
Most juveniles had reached a length of 35 mm by late April 1982
(ADF&G 1983b).The mean size of juvenile chum in the
Talkeetna-to-Devil Canyon reach (RM 98.6-152)was 42 mm (length
range 29-55 mm)during the first two weeks of July 1982 (ADF&G
1983b).
(vi)PopUlation Estimates
The popUlation size of juvenile chum was estimated in the
Talkeetna-to-Devil Canyon reach (RM 98.6-152)in 1983.Fry
were fin clipped and tagged with half-length coded wire tags at
sloughs 8A,9,11 and 21 and at Indian River.Outmigrating fry
were captured at downstream outmigrant traps at RM 103 and
102
....
--
examined for marks.The population size was an estimated
3,322,000 fish using the Peterson mark/recapture estimator and
3,037,000 fish using the Schaefer estimator (Schmidt et ale
1984)•
survival estimates for egg to fry were calculated by dividing
the population estimate by the total potential egg deposition.
Survival from egg to fry was 14.1 percent using the Peterson
estimate of population size and 12.9 percent using the Schaefer
estimate of population size (Schmidt et ale 1984).The
survival rate (13-14 percent)for egg to fry for chum salmon in
the Talkeetna-to-Devil Canyon reach is within the range
(0.4-35.4 percent)of those reported from other studies
(Schmidt et ale 1984).
Daily outmigration rates,population size and recruitment rates
of juvenile chum were estimated at Slough 11 in 1983 (Schmidt
et ale 1984).Fish were tagged with half-length coded wire
tags and marked with Bismark Brown dye so that fish marked over
a three day period could be separated upon recapture by the
particular day they were marked.On day two of the experiment,
the juvenile chum population size in Slough 11 was an estimated
2,068 fish,the daily emigration rate was 32.7 percent of the
population,and the daily recruitment (emergence)rate was ~.84
percent of the population (Schmidt et ale 1984).
A comparison of data from the east bank outmigrant trap at
RM 103 for 1982 and 1983 indicates that in 1983 juvenile chum
catch rates were 2.3 times higher than 1982 catch rates
(Schmidt et ale 1984).This relative abundance of juvenile
chum corresponds with the pt-rent spawner relative abundance.
The 1982 chum escapement (29,400 fish)at Curry station
(RM 120)was 2.2 times higher than the 1981 escapement (13,100
fish)(Barrett et ale 1984).
103
-
-
-
4.3.3 Coho Salmon
(i)Emergence
Coho emergence likely occurs before May in the Talkeetna-
to-Devil Canyon reach (RM 98.6-152)as the downstream
outmigrant traps (RM 103)began catching age 0+juvenile coho
in mid-May 1983 (Schmidt et ale 1984).However,the emergence
likely extends over a considerable time period,based upon the
shorter lengths of fish observed in June and JUly 1981,1982
and 1983 (ADF&G 1981b,1983b;Schmidt et ale 1984).Scott and
Crossman (1973)also report that coho emergence can occur from
early March to late July,depending upon time of spawning and
incubating water temperatures.
(ii)Seasonal Movements
There is a pattern of downstream movement of juvenile coho
throughout the summer in the Talkeetna-to-Devi1'Canyon river
reach (RM 98.6-152)(Figure 26).Some juvenile coho of all age
groups (age 0+,1+,2+)leave the Talkeetna-to-Devil Canyon
sub-basin (ADF&G 1983b,Schmidt et ale 1984).
Most juvenile coho (96 percent)were distributed in tributary,
upland slough and side slough habitats in the Talkeetna-to-:
Devil Canyon sub-basin during 1983 (Figure 27).Important
tributaries for juvenile rearing in 1983 were spawning areas
for adult coho in 1982 (ADF&G 1982a).Whiskers Creek,Chase
Creek and Indian River had the highest juvenile coho densities,
based upon mean catch per cell,of the tributaries in 1983
(SchmiL.t et ale 1984).
Sloughs 6A and 5 were important upland sloughs for juvenile
coho rearing,while Whiskers Creek Slough and Slough 8 were
important side sloughs in 1983 (Schmidt et ale 1984).The
104
1 )])j 1 )))I 1 )'I
26 31II1621
AUGUST ~I
617ZZ27
JULY .1.
127
o ,(".I I I'I -i""I I ",'."'(".'1"""1 tte'r-'·"I''''Y·('y""'j'_.,I I I
18 23 28 2 7 12 17 22 27 2
!'-MAY .1.JUNE ~I.
DATE
10 -COHO,AGE to
9 I I -,-COHO,AGE • I
8
a:
::>7a
r
6
0::
Wa.5-
:r:4u
l-
I
<t 3I-'U
0
U1
Z
COHO SALMON AGE 0+AND AGE t OR OLDER DAILY CATCH PER HOUR RECORDED AT
THE DOWNSTREAM MIGRANT TRAPS.MAY 18 THROUGH AUGUST 30.1983.(SOURCE:
SCHMIDT et ai,1984),
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 26
Woodward-Clyde Consultants .
and
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HARZA-EBASCO
SUSITNA JOINT VENTURE
)I -J ))J ]))i J J J J j "j
W hi ....n Cr ....
SlouQh \
.......(11Vu SlouQh
____.""Comblntd
1.2·'.
Whl.ker.
Cr....\
SlouQh
Maln.l.m No.Zi.a .,.
Four'lIn Moiftl'.m Sid.
Chonn.l.Combln.d
O.D .,.
SlouOh 19...,.
~
UPLAND SLOUGHS
SIDE SLOUGHS MAINSTEM SIDE
~~CHANNEL
,.e .,.
4.0 .".FOllr Trlbutorl..1.,/
Cornbln.d 3.2·'.
Cho ..
Cr ....~
TRIBUTARIES ...-----
Indian Rlvlf6.9·'.
Whi.Il.,.
Crull
~o
0'1
COMBINED MACROHABITAT
TYPES
DISTRIBUTION OF JUVENILE COHO SALMON BY MACROHABITAT TYPE ON THE SUSITNA RIVER BETWEEN THE CHULITNA
RIVER CONFLUENCE AND DEVIL CANYON,MAY THROUGH NOVEMBER 1983.PERCENTAGES ARE BASED ON MEAN CATCH
PER CELL.(SOURCE:SCHMIDT et al.1984)
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 27
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the
that
water
coho
-
-
-
presence of juveniles in these sloughs coupled with
infrequent catches in side channel habitat suggests
juvenile coho are found primarily in low-velocity,clear
areas.Upland and side sloughs may also attract juvenile
due to higher water temperatures (Schmidt et a1.1984).
significant overwintering of juvenile coho in the
Ta1keetna-to-oevi1 Canyon reach occurs in side sloughs and
upland sloughs (Schmidt et a1.1984).In 1981 through 1983,
Whiskers Creek Slough (side slough)and Slough 6A (upland
slough)were used for overwintering by age 1+and 2+coho.
Some coho may also use the mainstem,side channels and
tributaries for overwintering.
(iii)Food Habits
Food habits were examined in August and September 1982 in the
Ta1keetna-to-oevi1 Canyon reach (RM 98.6-152).Chironomids
were the dominant food item numerically in samp~es collected.
Since chironomids are small,their volumetric contribution is
probably less than their numeric contribution.E1ectivity
indices suggested a positive selection for chironomid larvae.
Other dipterans,and mayfly and stonef1y nymphs were
occasionally eaten.Riis and Friese (AOF&G 1978)found that
juvenile coho in the Susitna River fed on drifting aquatic
insect larvae in the spring,while the adult stage of aquatic
insects were major food items during the summer and fall.
Scott and Crossman (1983)report that juvenile pink,chum and
sockeye can be important food items for age 1+and older coho.
These food :tems are more likely to occur in coho diets between
May and August,when juvenile pink,chum and sockeye are more
numerous in the Ta1keetna-to-oevi1 Canyon sub-basin.
107
_.
-
-
....
(iv)outmiqration Timing
The outmigration of juvenile coho from the Talkeetna-to-Devil
Canyon reach (RM 98.6-152)was monitored by downstream migrant
traps (RM 103)during 1982 and 1983 (V)F&G 1983b,Schmidt et
a1.1984).There was a downstream movement of juvenile coho
throughout the summer (Figure 26).Age 0+fish accounted for
over 90 percent of the trap catch of 5,646 coho,whil~age 1+
and 2+fish comprised the remaining portion (schmidt et ale
1984).
From November 1980 to May 1981 age 2+coho were captured in the
Ta1keetna-to-Devi1 Canyon reach (ADF&G 1981b).After May in
this reach of river and mid-June in the Cook Inlet to Talkeetna
reach no age 2+coho were caught.Catches of age 2+coho were
low at the outmigrant traps at RM 103,however it appears that
catches peaked in early June in 1982 and 1983 (ADF&G 1983b,
Schmidt et ale 1984).Analyses of scales in 1982 and 1983 from
returning adult coho salmon at Curry Station (RM,120)indicate
that most coho outmigrate from the Susitna River as age 1+or
2+smo1ts (ADF&G 1981a, 1982a,Barrett et a1.1984).
Analyses were done to compare juvenile coho outmigration catch
rates at RM 103 with mainstem discharge (Schmidt et ale 1984).
The coefficie~t of determination (r2 )between mainstem
discharge and outmigration rates was 0.17 for age 0+fish and
0.22 for age 1+fish.
(v)Size
The average size of age 0+coho in the Talkeetna-to-Devi1
Canyon sub-basin (RM 98.6-152)was 56 mm in late June 1981 and
41 mm in late June 1982.The size increased to 63 mm in late
September in 1981 and 65 mm in late september 1982 (ADF&G
1981b,1983b).In 1983,age 0+coho were separated from age 1+
and older coho by length frequency and scale analyses~age 0+
108
-
coho were less than 46 rom in early May,less than 66 rom in late
June,and less than 96 rom in late September (Schmidt et al.
1984)•
Length frequency and 3cale analyses of coho salmon cannot be
used to separate age 1+and 2+coho because of overlapping
lengths (ADF&G 1983b).Therefore,age 1+and 2+fish were
combined as age 1+and older in most analyses (Schmidt et al.
1984)•
(vi)Population Estimates
Population size and survival estimates of juvenile coho have
not been done in the Susitna River.Catches of juvenile coho
in 1982 suggest that the river reach downstream of RM 98.6 is
used more for coho rearing than the reach upstream of RM 98.6.
About 80 percent of the 1,857 juvenile coho caught in 1982 were
captured downstream of RM 98.6 (ADF&G 1983b).
A comparison of data from the east bank outmigrant trap at RM
103 for 1982 and 1983 indicates that in 1983 juvenile coho
catch rates were 2.8 times higher than the 1982 catch rates
(Schmidt et al.1984).This relative abundance of juvenile
coho corresponds with the parent spawner relative abundance.
The 1982 coho escapement (2,400 fish)at Curry station (RM 120)
was 2.2 times higher than the 1981 escapement (1,100 fish)
(Barrett et al.1~84).
~4.3.4 Pink Salmon
(i)Emergence
-
The emergence of pink salmon probably occurs in March and April
in the Talkeetna-to-Devil Canyon reach (RM 98.6-152).Limited
information obtained in 1981 indicated that fry appeared in
Slough 11 and Indian River on April 11 (ADF&G 1981b).
109
..-
(ii)Seasonal Movements
After emergence juvenile pink salmon move almost immediately
downstream to the ocean (ADF&G 1981b,1983b;Schmidt et ale
J.984).All juveniles in the Susitna River outmigrate in their
first summer (age 0+fish)and little if any freshwater rearing
occurs.
Most juvenile pink salmon were captured in the downstream
outmigrant traps (RM 103)in May and June (Figure 28).In
1982,the downstream outmigrant trap caught only seven juvenile
pink during early JUly (ADF&G 1983b).In 1983 the downstream
outmigrant traps caught few juvenile pink after July (Schmidt
et al.1984).
(iii)Food Habits
It is uncertain if juvenile pink salmon feed in the Susitna
River.They apparently spend little time in the Talkeetna-
to-Devil Canyon reach (RM 98.6-152)after emergence (Schmidt et
ale 1984).Scott and Crossman (1973)indicate that juvenile
pink salmon remain in freshwater for such a short time that
many do not feed at all.However,those that migrate longer
distances to the estuary may eat nYmphal and larval insects.
It is likely that juvenile pink salmon in the Talkeetna-to-
Devil Canyon sub-basin may feed occasionally on chironomid
larvae and other aquatic insects during their outmigration.
(iv)OUtmigration Timing
_After emergence in April and Ma~,juvenile pink move almost
immediately downstream to the estuary.In 1983 juvenile pink
catches were highest at the outmigrant traps (RM 103)during
late May and early June (Figure 28).
110
J -1 1 )J ).~-J »J .~J »J j J
1.0
13 18 23 28 3 8
JUNE .14 JULY----l
DATE
8324 29
I-MAY .,-
0'I I \.J19Iii I ~~I I j I
0.8
cr:
::>
0
::I:0.6
cr:
wa..
0.4
J:
0
......I
...
......
-t
......
0 0.2
PINK SALMON FRY BAilY CATCH PER HOUR RECORDED AT THE DOWNSTREAM MIGRANT TRAPS.
MAY 18 THROUGH JULY 8.1983.(SOURCE:SCHMIDT et al.1984)
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 28
Woodward-Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
Analyses were done to compare 1983 juvenile pink outmigration
catch rates at RM 103 with mainstem discharge (Schmidt et al.
1984)•During mid-May to mid-July about 30 percent of the
variation in catch rates was accounted for by mainstem
discharge.The coefficient of determination_(r2 )between
mainstem discharge and outmigration rates was 0.30;r =0.55
(Schmidt et al.1984).
(v)Size
The average size of juvenile pink,between RM 79 and 136,was
36 mm (length range 29-43 mm)during late May to late July 1982
(ADF&G 1983b).No increase in size was observed between fish
measured in May compared to those measured in July.However,
the sample size was small (28 fish).It appears that juvenile
pink grow little,if any,during their freshwater residence.
(vi)Population Estimates
No estimation of the population size of juvenile pink salmon in
the Talkeetna-to-Devil Canyon reach (RM 98.6-152)has been
done.Catches have been low for this species.In 1982,only
six fish were caught in the downstream migrant trap (RM 103),
while in 1983,245 juveniles were captured (ADF&G 1983b,
Schmidt et al.1984).
Adult runs of pink salmon are numerically dominant in even
years in the Susitna River,with even-year escapements about 10
times greater than odd-year escapements (ADF&G 1981a,1982a;
Barrett et al.1984,1985).The progeny of even-year pink
salmon emerge and outmigrate in the following odd year.
Therefore,the abundance of juvenile pink salmon is likely
greater in odd years than in even years.
112
--I
-
4.3.5 Chinook Salmon
(i)Emergence
Most chinook salmon emerge from the gravel in tributaries of
the Ta1keetna-to-Devi1 Canyon reach (RM 98.6-152)in March or
April (ADF&G 1983d).Juvenile chinook had emerged prior to
mid-April in Indian River in 1981 (ADF&G 1983c).
(ii)Seasonal Movements
In.other river systems juvenile chinook usually spend one or
two years in freshwater residence before outmigrating to the
ocean (as age 1+or 2+smo1ts)(Scott and Crossman 1973,Morrow
1980).Most juveniles in the Ta1keetna-to-Devi1 Canyon
sub-basin (RM 98.6-152)spend one year in freshwater before
going to sea as age 1+smo1ts (ADF&G 1981a,b;1982a,Barrett et
a1.1984;Schmidt et a1.1984).
One to two months after emergence there is a downstream
movement of some juvenile chinook (age 0+)from areas of high
post-emergent densities (natal tributaries)to rearing and
overwintering areas (mainstem,side channels,side sloughs,
upland sloughs and tributary mouths)(ADF&G 1981b,1983b;
Schmidt et a1.1984).The downstream redistribution of age 0+
juvenile chinook has been observed in the Deshka River
(RM40.6).by Delaney et a1.(1981),in Montana Creek (RM 77)by
Riis and Friese (ADF&G 1978)and in the Little Susitna River
(eight miles east of the Susitna River mouth)by Delaney and
Wadman (ADF&G 1979).Some juveniles move downstream and leave
the Ta1keetna-to-Devil Canyon reach.The downstream out~igrant
traps (RM 103)in 1983 captured age 0+juvenile chinook
throughout the season with a major peak catch occurring in
August (schmidt et a1.1984).
113
-I
Important rearing habitats for juvenile chinook are side
sloughs,side channels,upland sloughs and tributary mouths
(ADF&G 1981b,1983b;Schmidt et a1.1984).Apparently
juveniles prefer areas of moderate water velocity and depth,
and utilize turbidity for cover (Schmidt et a1.1984).These
conditions are often present in side channels.Consequently,
densities of juvenile chinook were higher in side channels than
in side or upland slough habitats (Figure 29).
Side sloughs,tributaries,the mainstem,and side channels are
used by juvenile chinook for overwintering areas (ADF&G 1981b,
1983b;Schmidt et ale 1984).Side sloughs may attract
overwintering juvenile chinook because of the warmer water
temperatures that are associated with groundwater upwelling in
sloughs (Schmidt et a1.1984).
In 1981 juvenile chinook were captured throughout the Susitna
River from Alexander Creek (RM 10.1)upstream to Portage Creek
(RM 148.8)(ADF&G 1981b);in 1982 fish were collected between
Goose Creek (RM 73.1)and Portage Creek (RM 148.8)(ADF&G
1983b)•In both years juvenile chinook abundance was higher
downstream of the Chulitna River (RM 98.6).
(iii)Food Habits
Juvenile chinook food habits were examined in August and
September 1982 at sloughs 8A,11,20,21 and at Indian River
and Fourth of July Creek (ADF&G 1983b).Fish were found to be
feeding primarily on chironomid larvae,pupae and adults.
However,dominance of food items was based on numbers and not
biomass or volume.Since ,~hironomids are small,their
volumetric importance may be overemphasized by the numerical
method.E1ectivity indices indicated that juvenile chinook had
a positive selection for chironomid larvae.Terrestrial and
other aquatic insects were also eaten (ADF&G 1983b).
114
j ]-J ')1 J J )})J 1 J J J 'u l
Molnatem "9.3!Y_Oxbow One
Eight Sites \/B.2-'_
Combined 4.0!Y_
Slough 22
Whiskers Creek
Slough
Side Channel 10
Oxbow One
10.7%
--Sid,Chonn.1
10 oJ 17.9-'_
Twelve Sit"
Combined
Slough 9
SIDE
CHANNELS
SiDE SLOUGHS~
Five Trlbutorles
Combined 10.4-'_
6'~UPLAND SLOUGHS
COM BIN ED MACROHABITAT
TYPES
I-'
I-'
U1
DISTRIBUTION OF JUVENILE CHINOOK SALMON BY MACROHABITAT TYPE ON THE SUSITNA RIVER BETWEEN
THE CHULITNA RIVER CONFLUENCE AND DEVIL CANYON,MAY THROUGH NOVEMBER 1983.PERCENTAGES ARE
BASED ON MEAN CATCH PER CELL.I (SOURCE:SCHMIDT et al.1984)t,
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 29
Woodward·Clyde Consultants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
-
-
-
(iv)outmigration Timing
There is a downstream movement of age 0+chinook throughout the
summer (mid-May through August)with a major peak occurring in
August (Figure 30).These age 0+chinook likel~redistribute
to rearing and overwintering areas downstream of RM 103.
Age 1+chinook leave the Talkeetna-to-Devil Canyon sub-basin
primarily in May and June (ADF&G 1983b).In 1983,the
outmigration of age 1+chinook at RM 103 was over by mid-July
(Figure 30).Age 1+chinook apparently leave the Susitna River
by September as no age 1+juveniles were captured between Cook
Inlet and Talkeetna station (RM 103)after the end of August
(1981b)•
Analyses were done to compare 1983 juvenile chinook
outmigration catch rates at RM 103 with mainstem discharge
(Schmidt et ale 1984).The coefficient of determination (r2 )
between mainstem discharge and outmigration rates I was 0.25 (r =
0.50)for age 1+fish and 0.19 (r =0.44)for age 0+fish.
Thus 25 and 19 percent of the variation in outmigration rates
was accounted for by mainstem discharge.
(v)Size
Age 1+chinook averaged 90 rom in length during May and June in
1981 and 1982 (ADF&G 1983b).This is when most age 1+chinook
leave the Talkeetna-to-Devil Canyon sub-basin (RM 98.6-152).
In this reach of the Susitna River,age 0+and age 1+chinook
can be separated by length frequency analysis (Schmidt et ala
1984).In early May age 0+chinook upstream of RM 103 are less
than 56 mm,in early June they are less than 71 mm,and in
early July they are less than 81 mIn.After August 1 all
chinook upstream of RM 103 are considered age 0+fish (Schmidt
et ale 1984).
116
1 .I.}--1 ))J J J 1 )j B J }
150 -CHINOOK,AGE '0
-'.CHINOOK,AGE • I
12.5-
302214
AUGUST ./
6292113~2719II326
J--MAY ·1.JUNE ...,-JULY ...,.
,)..(',-•.....,~;:>-'J#.-.~.'V'~
0-.I I 'r ,I .I I"I I I I I Iii
18
10.0a::
:J
a
:I:
n:7.~
w
Q.
:I:
U
~.-~.O
~0':{
-..J u
2.5
DATE
CI-l'NOOK SALMON AGE 0+AND AGE 1+DAILY CATCH PER HOUR RECORDED AT THE DOWNS "REAM
MIGRANT TRAPS,MAY 18 THROUGH AUGUST 30,1983.(SOURCE:SCHMIDT et al.1984):
ALASKA POWER AUTHORITY
SUSITNA HYDROELECTRIC PROJECT
FIGURE 30
Woodward-Clyde Consul~ants
and
ENTRIX,INC.
HARZA-EBASCO
SUSITNA JOINT VENTURE
the Susitna Basin below Devil
from Talkeetna,they mainly use
rearing,while overwintering
(Schmidt et al.1984).
......
Downstream of Talkeetna station (RM 103),it is not possible to
separate age 0+and age 1+chinook from length frequency data
alone because of overlapping lengths of the two age groups.
After September 1 all juvenile chinook downstream of RM 103 are
considered to be age 0+fish (A~'F&G 1981b).
(vi)Population Estimates
No estimate of population size for juvenile chinook has been
done in the Susitna River.In 1982 juvenile chinook abundance
in the Talkeetna-to-Devil Canyon sub-basin was lower than in
1981 and 1983 (Schmidt et al.1984).Comparisons of the
catches at the east bank downstream migrant trap (RM 103)
between 1982 and 1983 indicate that juvenile chinook abundance
was over four times greater in 1983 than for the same time
period in 1982 (Schmidt et al.1984).
4.4 RESIDENT SPECIES
4.4.1 Rainbow Trout
Rainbow trout occur throughout
Canyon (ADF&G 1983b).upstream
tributaries for spawning and
occurs primarily in the mainstem
upstream of the·Chulitna River confluence (RM 98.6),rainbow
trout move into tributaries to spawn in late May and early June
(Schmidt et al.1984).Whiskers Creek (RM 104.4),Lane Creek
(RM 113.6)and Fourth of July Creek (RM 131.1)are the major
spawning areas in this r:~er reach,whereas the larger
tributaries (Indian River and portage Creek)are of lesser
importance (Schmidt et al.1984).Both sexes mature by age 5+
(Schmidt et al.1984).
118
-
There is a post-spawning movement from spawning areas to
feeding areas (Schmidt et ale 1984).These feeding areas may
be located in the same tributaries in which spawning occurred,
or in other tributaries and at tributary mouths (ADF&G 1983b,
Schmidt et a 1,.1984).During August and September rainbow
trout can be found in sloughs and at tributary mouths that are
occupied by adult salmon (ADF&G 1983b,Schmidt et ale 1984).
It is suspected that rainbo~trout feed on salmon eggs at these
sites (Schmidt et ale 1984).
Juvenile rainbow trout rear mainly in tributaries (ADF&G 1983b,
Schmidt et ale 1984).Some juveniles also rear in the mainstem
and sloughs,but the use of these habitats appears to be
limited (ADF&G 1983b,Schmidt et ale 1984).Fourth of July
Creek (RM 131.1)is an important rearing area for juvenile
rainbow trout (Schmidt et ale 1984).
In the fall,rainbow trout move out of tributaries into the
mainstem to overwinter (ADF&G 1983b,Schmidt et ale 1984).By
early December in 1983,most radio-tagged rainbow trout were
located in mainstem areas that were not influenced by tributary
inflow (Schmidt et ale 1984).
Based on recaptures from three years of tagging (1981-1983),
the population size of rainbow trout in the Talkeetna-to-Devil
Canyon reach was estimated to be about 4,000 fish.(greater than
150 mIn in length)(Schmidt et ale 1984).This estimate s~lould
be viewed as an approximation because it does not account for
annual recruitment,mortality or emigration (Schmidt et ale
1984)•
4.4.2 Arctic Grayling
Arctic grayling are found throughout the Susitna Basin (ADF&G
1983b).In the Talkeetna-to-Devil Canyon reach,Arctic
grayling primarily use mainstem habitats for overwintering and
119
-
.-
tributaries for spawning and rearing (ADF&G 1983b,Schmidt.et
ale 1984).
upstream of Talkeetna,Arctic grayling move into tributaries to
spawn in May and early June (ADF&G 1983b,Schmidt et ale 1984).
High catches occurred in Whiskers Creek Slough (RM 101.2),Lane
Creek (RM 113.6),Fourth of July Creek (RM 131.1),!Indian River
(RM 138.6),Jack Long Creek (RM 144.5)and Portage Creek
(RM 148.8)in 1982 and 1983 (Schmidt et ale 1984).Al though
these tributaries have not been identified as spawning areas,
they are likely candidates.Spawning may also occur in the
mainstem.In 1983,it was suspected that spawning occurred at
or near RM 150.1 (Schmidt et ale 1984).
After spawning,most adults and juveniles remain in tributaries
or move to tributary and slough mouths until early September
(ADF&G 1983b,Schmidt et ale 1984).Some juvenile fish rear in
mainstem areas (ADF&G 1983b,Schmidt et ale 1984).These
juveniles may be displaced from tributary hal:;litat by the
territorial behavior of older,larger fish (ADF&G 1983b,
Schmidt et ale 1984).
During September,Arctic grayling move into the mainstem from
tributaries (ADF&G 1983b,Schmidt et ale 1984).It is sus-
pected that this movement to the mainstem is for overwintering,
however specific areas have not been identified (Schmidt et ale
1984).Some fish may use the larger,deeper pools in Portage
Creek for overwintering (Schmidt et ale '1984).
4. 4•3 Burbot
Burbot occur throughout the Susitna River basin (ADF&G 1981d,
1983b).Burbot appear to be more abundant downstream from the
t-Chulitna River confluence (RM 98.6)(Schmidt et a1.1984).
120
-
Burbot are associated almost exclusively with the mainstem and
mainstem-influenced areas.
Burbot apparently move to spawning areas in the winter and then
disperse to feeding areas after spawning is completed (ADF&G
1983b,Schmidt et ale 1984).Other than these migrations,
burbot are generally sedentary (ADF&G 1983b).Burbot spawning
takes place from mid-January to early February in mainstem-
influenced areas (ADF&G 1983a,Schmidt et a1.1984).Tributary
and slough mouths are thought to be important areas of
spawning,as are mainstem areas with groundwater upwelling
(ADF&G 1983a,Schmidt et a1.1984).Spawning areas have not
been located in the Talkeetna-to-Devil Canyon reach (Schmidt et
ale 1984).Downstream of Talkeetna,the mouth of the Deshka
River (RM 40.5)is a known spawning area (ADF&G 1983a).
Due to the limited catch data,juvenile rearing areas are
unknown.It is suspected that juvenile burbot rear in the
mainstem,tributary and slough mouths,and clea~ater sloughs
(ADF&G 1981d,1983b).
In 1983,15 burbot were estimated to occur between RM 138.9 and
140.1 (Schmidt et a1.1984).This population estimate should
be viewed as an approximation because few fish were caught dur-
ing this study (Schmidt et ale 1984).However,it appears that
the burbot population size in the middle Susitna River is low.
4.5 OTHER SPECIES
4.5.1 Round Whitefish
Round whitefish occur throughout the Susitna River drainage
(ADF&G 1981d).Downstream from Devil Canyon,they appear to be
121
--
....
,~
.~
more abundant in the middle river reach (ADF&G 1983b).Within
this reach,round whitefish are most numerous between RM 132.6
and 150.1 (Schmidt et al.1984).
Round whitefish were found in tributaries c...I'1d sloughs more
often than mainstem areas in 1982 and 1983 (Schmidt et al •
1984)•The mainstem is used for some spawning and juvenile
rearing,and as a migrational corridor.
During September,there is an upstream migration of round
whitefish that is thought to be associated with spawning (ADF&G
1983b).This species spawns in the mainstem and at tributary
mouths in October (ADF&G 1983b,Schmidt et al.1984).During
1981 through 1983,nine spawning areas were identified upstream
of Talkeetna.Mainstem sites were:RM 100.8,102.0, 102.6,
114.0,142.0 and 147.0 (Schmidt et al.1984).Round whitefish
may also spawn in tributaries,such as Indian River and Portage.
Creek (Schmidt et al.1984).
Juvenile round whitefish rear mainly in the mainstem and
sloughs (ADF&G 1983b,Schmidt et al.1984).Slow velocities
and turbid water are apparently preferred (Schmidt et al.
1984)•overwintering areas of round whitefish have not been
identified (ADF&G 1983b).
4.5.2 Longnose Sucker
Longnose suckers occur throughout the Susitna Basin (Schmidt et
al.1984,Sautner and Stratton 1984).They appear to be more
abundant downstream of the Chulitna River confluence (RM 98.6)
(Schmidt et al.1984).In the Talkeetna-to-Devil Canyon reach
(RN 98.6-152),longnose suckers are primarily associated with
tributary and slough mouths,although the mainstem is also used
throughout the open-water season (ADF&G 1983b,Schmidt et al.
1984).The major overwintering and juvenile rearing areas of
this species are unknown (ADF&G 1983b).The mouths of Trapper
122
Creek (RM 91.5)and Sunshine Creek and side channel (RM 85.7)
are known spawning areas (ADF&G 1983b).
-4.5.3 Humpback Whitefish
Humpback whitefish are found downstream of Devil Canyon between
RM 10.1 and 150.1 (Schmidt et al.1984).They appear to be
more abundant downstream from the Chul i tna River confluence
(RM 98.6)(Schmidt et al.1984).In the Talkeetna-to-Devil
Canyon reach,tributary and slough mouths are used by adults -
most frequently,with the mainstem serving mainly as a
migrational corridor (ADF&G 1983b,Schmidt et al.1984).Due
to low catches of humpback whitefish,little is known of their
overwintering,spawning and juvenile rearing areas (ADF&G
1983b,Schmidt et ale 1984).It is suspected that they spawn
in tributaries during October (Schmidt et al.1984).
4.5.4 Dolly Varden
'~
Dolly Varden occur throughout the Susitna Basin (Schmidt et al.
1984).In the Ta1keetna-to-Devil Canyon reach,Dolly Varden
are found primarily in the upper reaches of tributaries and at
tributary mouths (ADF&G 1983b,Schmidt et a1.1984).They
apparently use the mainstem for overwintering (Schmidt et al.
1984).Spawning and juvenile rearing areas are suspected to be
in tributaries (ADF&G 1983b).The population size of Dolly
Varden in the Talkeetna-to-Devil Canyon reach appears tc be low
and they are apparently more abundant downstream from the
Chulitna River confluence (RM 98.6)(Schmidt et al.1984).
4.5 5 Arctic Lamprey
Arctic lamprey have been found in the susitna River as far
upstream as Gash Creek (RM 111.5),however they are more
abundant downstream of RM 50.5 (ADF&G 1983b,Schmidt et al.
123
-
1984).Most fish have been found in tributaries and tributary
mouths (ADF&G 1983b,Schmidt et al.1984).
4.5.6 Threespine stickleback
Threespine stickleback have been caught in the Susitna River as
far upstream as RM 146.9,but they are more abundant downstream
of the Chulitna River confluence (RM 98.6)(ADF&G 1983b,
Schmidt et al.1984).Spawning and juvenile rearing apparently
occur in tributary and slough mouths (ADF&G 1983b).Over-
wintering areas of this species are unknown (ADF&G 1983b)•
4.5.7 Bering Cisco
Bering cisco occur mainly downstream of the Chulitna River
confluence (RM 98.6)in the Susitna River (Barrett et al.
1984)•In 1981 and 1982,the major spawning areas for this
species were in the mainstem between RM 75 and 85 (Barrett et
al.1984).In 1982,most spawning fish were age 5 that had
gone to the ocean for rearing in their first summer (ADF&G
1982a)•
4.5.8 Eulachon
Eulachon occur in the Susitna River as far upstream as RM 50.5,
but are more abundant downstream of RM 29 (Barrett et a1.
1984).Because eulachon are not found in the middle reach of
the Susitna River,they are not discussed in great detail.
Information on preferred habitat and life history information
can be found in reports by Barrett et al.(1984)and
Vincent-Lang and Queral (1984).Eulachon enter the Susitna
River in two runs (Barrett et a1.1984).The first run enters
the river during the last two weeks of May,while the second
run follows during the first two weeks of June (Barrett et a1.
1984).Fish from both runs spawn in the mainstem (Barrett et
al.1984).The first-run population size is likely several
124
--
hundred thousand fish,while the second run is probably several
million fish (Barrett et al.1984).In 1982,most returning
adults were age 3 that had gone to the ocean for rearing in
their first summer (ADF&G 1982a).
4.5.9 sculpin
Slimy sculpin occur throughout the Susitna River drainage
(ADF&G 1981e,1983b).They are most abundant in tributaries
and tributary mouths,although the mainstem is also used (ADF&G
1983b)•Sculpin in the Susitna River are sedentary with
spawning,juvenile rearing and adult movements confined to a
limited area (ADF&G 1983b).In addition to slimy sculpin,
other species of sculpin may occur in the lower Susitna River
(ADF&G 1981d).
4.5.10 Lake Trout
Lake trout occur throughout the Susitna Basin I primarily in
larger,deeper lakes.Occasionally they can be found in the
inlet or outlet streams of these lakes.Lake trout have not
been captured in the mainstem-influenced areas of the Susitna
River below Devil Canyon (ADF&G 1981.b,1983b;Schmidt et al.
1984).
4.5.11.Northern Pike
Northern pike were apparently illegally transplanted into
severa1.lakes in the Yentna River drainage (RM 28)during the
1950's (ADF&G 1981d).During 1981 one northern pike was
captured in the Susitna River at Kroto Slough (~~30.1)(ADF&G
1981d).
125
.~..
-
.-
4.5.12 Ninespine stickleback
Ninespine stickleback are apparently rare in the Susitna River.
This species has been captured in the vicinity of the Deshka
River (RM 40.5)(ADF&G Su Hydro,unpublished data).
126
~.
--
......
-
5.0 SUMMARY OF HABITAT UTILIZATION
5.1 MAINSTEM AND SIDE CHANNEL HABITATS
Mainstem habitat is comprised of those portions of the susitna
River that normally convey streamflow throughout the year
(Figure 2).Both single and multiple channels are included in
this habitat category.The mainstem is typically characterized
by high water velocities and armored streaInbeds.Substrates
generally consist of gravel and cobble size materials with
interstitial spaces filled with a grout-like mixture of small
gravels and sands.Suspended sediment concentrations and
turbidity are high during summer due to the influence of
glacial melt-water.Streamflows recede in early fall and the
mainstem clears appreciably in October.An ice cover forms on
the river in late November or DeceInber and lasts until late
April or May (Trihey 1982,ADF&G 1983e).
side channel habitat consists of those portions of the Susitna
River that normally convey streamflow during the open-water
season but become appreciably dewatered during periods of low
flow (Figure 2).Side channel habitat may exist either in
well-defined overflow channels,or in poorly defined
watercourses flowing through partially submerged gravel bars
and islands along the margins of the mainstem river.Side
channels are characterized by shallower depths,lower
velocities and smaller streambed materials than the adj acent
habitat of the mainstem river (Trihey 1982,ADF&G 1983e).
5.1.1 Adult Salmon
Five species of Pacific salmon utilize the mainstem and side
channels upstream of the Chulitna confluence (RM 98.6),
primarily as a migrational corridor (ADF&G 1981a,1982a;
Barrett et ale 1984,1985).Migrational periods for adults of
each species are:
127
-Sockeye
Chum
Coho
Pink
Chinook
-July through mid-September;
-mid-July through mid-September;
-mid-July through mid-September;
-mid-July through August;and
-Ju~e through July.
Escapement estimates based on 1981 through 1984 data indicate
that the mainstem and side channels of the Talkeetna-to-Devil
~Canyon reach (RM 98.6-152)serve as'a migrational corridor for
less than 5 percent of the total Susitna River salmon
-escapement (ADF&G 1981a,1982a;Barrett et ale 1984,1985).
Generally,the upstream migration of adult salmon corresponds
with the summer high-flow season.However,peak river
discharge events apparently cause slowed upstream movements of
salmon until high flows subside (Figures 13, 15,17,19,21).
Slowed upstream migration was observed in the Talkeetna-
to-Devil Canyon reach at flows above 40,000 cfs at Gold Creek
(RM 136.8)(Sautner et ale 1984).
Mainstem and side channel spawning upstream of RM 98.6 has been
observed for sockeye,chum and coho salmon (ADF&G 1981a,1982a;
Barrett et ale 1984,1985).Chum salmon apparently utilize the
mainstem margins and side channels for spawning more than coho
or sockeye do.Peak counts of chum salmon spawning in mainstem
and side channel habitats were:14 fish in 1981,550 fish in
1982,219 fish in 1982 and 1,266 fish in 1984 (Table 14).Only
five coho and 44 sockeye were observed spawning in mainstem and
side channel habitats during 1981-1984.Most mainstem spawning
has been observed in late August to mid-September.The armored
streambed material,high water velocities and infrequent
upwelling sites apparently limit spawning in mainstem habitat.
In 1984,about 5 percent of the 68,750 salmon spawning upstream
of RM 98.6 used the mainstem for spawning (Barrett et a1.
1985).
128
-
5.1.2 Juvenile Salmon
Juvenile salmon of all five species utilize the mainstem and
side channels upstream of RM 98.6 as a migrational corridor.
Addit.,iona11y ,mainstem and side channels are important
overwintering areas for chinook and coho,and summer rearing
areas for chinook salmon.Periods of juvenile salmon mainstem
and side channel use in the Ta1keetna-to-Devi1 Canyon reach
(RM 98.6-152)are outlined be19w.
Sockeye -Juvenile sockeye use the mainstem and side
channels mainly for movements and outmigration.During
1982 and 1983 most juvenile sockeye moved out of the
Ta1keetna-to-Devi1 Canyon reach during June and July
(ADF&G 1983b,Schmidt et a1.1984)(Figure 24).Mainstem
and side channel habitats are relatively unimportant
rearing habitats for this species (Figure 23).
Chum -Juvenile chum leave natal tributaries and sloughs
in June and move into side channels and the mainstem
(Schmidt et a1.1984).During 1982 and 1983 most
juveniles had migrated downstream of RM 103 by mid-July
(ADF&G 1983b,Schmidt et a1.1984)(Figure 24).Juvenile
chum use mainstem and side channels for rearing in low
densities (Schmidt et a1.1984)(Figure 25).
C~ho -Relatively few juvenile coho utilized mainstem and
side channel habitats for rearing in 1983 (Figure 27).
They use these habitats primarily as a migrational
corridor and for overwintering.outmigration of juvenile
coho peaked during June in 1982 and in June,July and
August during 1983 (ADF&G 1983b,Schmidt et a1.1984)
(Figure 26).
129
.-
~.
Pink -Juvenile pink salmon use the mainstem and side
channels mostly as migrational corridors.Most fish moved
downstream of RM 103 during May and June in 1983
(Figure 28).Minimal freshwater rearing and growth occurs
for juvenile pink salmon because of their short residence
time (Schmidt et al.1984).
Chinook -Mainstem and side channels are important summer
rearing and overwin,tering habitats for juvenile chinook
(ADF&G 1981b,1983b;Schmidt et al.'1984)(Figure 29).
Additionally,these habitats are used as migrational
corridors.Most age 1+chinook moved downstream of RM 103
in May and June in 1981 through 1983 (ADF&G 1981b,1983b;
Schmidt et al.1984),while age 0+,chinook moved
downstream throughout the open water season/(Figure 30).
Analyses were done to compare 1983 juvenile salmon outmigration
rates with mainstem discharge (Schmidt et al.1984).The
correlation coefficient was highest for juvenile chum (r =
0.89;r 2 =0.79),indicating that outmigration rates for
juvenile chum may be influenced by river discharge levels.
Correlation coefficients were moderate to low for the remaining
juvenile salmon and ranged from r =0•55 (r2 =0.30)for
juvenile pink to r =0.24 (r2 =0.06)for age 1+sockeye.
5.1.3 Resident Species
Most resident species
migrational corridors.
whitefish,also spawn
et al.1984).
use the mainstem and side channels as
Some species,such as burbot and round
in these habitats (ADF&G 1983a,Schmidt
Themainstem appears to be an important overwintering area for
many resident fish.Rainbow trout,Arctic grayling and burbot
apparently use the mainstem extensively during the winter
(Schmidt et al.1984).Other species,such as Dolly Varden,
130
-
whitefish,and suckers,likely.overwinter in the mainstem.
However,overwintering areas have not been identified for these
species.
~.
Juvenile burbot,round whitefish and longnose suckers ~ear
primarily in mainstem and side channel habitats (ADF&G 1983b,.....
Schmidt et ale 1984).Some Arctic grayling and rainbow trout
juveniles also use these habitats (Schmidt et ale 1984).
5.2 SIDE SLOUGH AND UPLAND SLOUGH HABITATS-The clear water in sloughs originates from local surface runoff
and groundwater upwelling.Groundwater of 2-4 o C upwells in
some slough channels throughout the year,thus keeping these
areas relatively ice free in the winter.The shallow
infiltration from the Susitna River is the primary source of
the groundwater in many of the sloughs (APA 1984).Local
runoff can be an important source of water for some sloughs in
the summer.
-
-
The stage in the mainstem controls the water surface elevation
of the lower portion of the sloughs by forming a backwater that
can extend some distance upstream into the slough.This
backwater is divided into two parts--clear water from the
slough and turbid water from the mainstem.At high mainstem
discharges,the water level in the mouth of the slough raises
and backs up the clear water in the slough.As th~stage in
the mainstem drops,the size and character of the backwater
changes,reducing the depth of water at the entrance to most
sloughs.
When high mainstem flows overtop the upstream (head)end of the
sloughs,the flows flush out fine sediments that accumulate in
the lower portion of the sloughs.As peak flows in the
mainstem subside and the stage in the mainstem drops below the
head of the slough,discharge through the slough drops and the
water begins to clear,with sand in suspension settling out.
131
-
-
-
--
Because of the diversity in the morphology of individual
sloughs,the flows at which they are overtopped by the mainstem
vary considerably.Most side sloughs are overtopped at flows
between 15,000 to 25,000 cfs,although some sloughs are only
overtopped at high discharge leve~s (e.g.Slough 11 at
42,000 cfs).
In general,slough water temperatures are warmer than .mainstem
water temperatures in the winter,due to the strong influence
of groundwater upwelling in the sloughs.This may attract
overwintering juvenile anadromous and resident fish to these
areas (Schmidt et al.1984).
Upland sloughs differ from side sloughs in that the upstream
(head)end of the slough is rarely connected with the mainstem
Susitna River or its side channels (Figure 2).Upland sloughs
are characterized by near zero velocities and an accumulation
of silt covering the substrate resulting from the absence of
mainstem scouring flows.Beaver activity is common in upland
sloughs,and large backwater areas of the Susitna River.
5.2.1 Adult Salmon
sockeye,coho,pink and chum salmon have been observed spawning
in slough habitat in the Talkeetna-to-oevil Canyon reach
(RM 98.6-152)(AOF&G 1981a,1982a;Barrett et al.1984,1985).
Results of escapements and spawning surveys in 1981 through
1984 indicate that chum and sockeye are the most numerous
salmon in sloughs while pink and coho are less abundant.
Total slough escapements upstream of RM 98.6 for 1981 through
1984 are summarized below:
132
species 1981 1982 1983 1984 Average
Sockeye 2,178 1,488 1,060 2,203 1,732
Chum 4,501 5,057 2,944 14,634 6,784
Coho 0 2 0 0 1
Pink 38 297 0 647 Odd-years 19
Even-years 472
In 1984,about 25 percent of all spawning salmon (68,742 fish)
~upstream of RM 98.6 spawned in slough habitat (Barrett et a1.
1985).
Most slough-spawning salmon upstream of RM 98.6 spawn in August
and September (ADF&G 1981a,1982a;Barrett et al.1984,1985).
During 1981 through 1984,spawning activity occurred mainly
during the first three weeks of August for pink salmon,the
first week of September for chum salmon,and the first two
weeks of September for sockeye (ADF&G 1981a,1982a;Barrett et
al.1984,1985).
5.2.2 Juvenile Salmon
Sloughs are important habitats for juvenile
Talkeetna-to-Devil Canyon reach (RM 98.6-152)
serve as rearing and overwintering areas.The
hab;tat by juvenile salmon is discussed below.
salmon in the
because they
use of slough
,~
Sockeye -Most sockeye rear in sloughs (Figure 23).Natal
sloughs (8A,11 and 21)and upland sloughs are used most
frequently.Some sockeye also ovelwinter in slough
habitat (schmidt et al.1984).
Chum Sloughs provide important rearing habitat for
juvenile chum salmon (Figure 25).Chum salmon rear for
one to three months before they move downstream as smolts.
133
.-
/""'"
-
-
......
..-
-.
-
Most juvenile chum leave the Talkeetna-to-Devil Canyon
reach by mid-July (Schmidt et al.1984).
Pink -The extent of slough utilization by juvenile pink
is limited because they spend little time in freshwater
(ADF&G 1983b,Schmidt et al.1984).Pink salmon natal
sloughs are listed in Table 18.
Coho -Some juvenile coho move from natal tributaries to
upland and side sloughs for rearing (Figure 27).Juvenile
coho apparently prefer clear water and lower velocities
(Schmidt et al.1984).These conditions usually occur in
upland sloughs more frequently than in side sloughs.Some
juvenile coho use sloughs for overwintering.
Chinook -Juvenile chinook used side sloughs and upland
sloughs for rearing in relatively low densities in 1983
(Figure 29).However,sloughs apparently provide
important feeding areas for juvenile chinook during the
fall,salmon-spawning period.During the period,juvenile
chinook move into sloughs to feed on salmon eggs (schmidt
et al.1984).Sloughs may be important overwintering
habitat for juvenile chinook.
5.2.3 Resident species
Sloughs are rearing areas for some resident fish.Rainbow
trout,Arctic grayling and round whitefish use sloughs and
slough mouths for rearing,while some burbot rear in slough
mouths (Schmidt et al.1984).These fish apparently feed on
salmon eggs in.sl~ughs during the salmon-spawning period .
spawning in sloughs by resident fish appears to be limited.
Burbot and longnose sucker may spawn in slough mouths (ADF&G
1981a,1984b).The extent of overwintering in sloughs by
resident fish is unknown.
134
.-
--
~-
.-
-
--
-
5.3 TRIBUTARY AND TRIBUTARY MOUTH HABITATS
Tributary streamflow,sediment,and thermal regimes reflect the
integration of the hydrology,geology,and climate of the
tributary drainage (Figure 2).Hence,the physical attributes
of tributary habitats are not dependent on mainstem conditions.
Tributary mouth habitat extends from the uppermost point that
the tributary is i1",fluenced by either the mainstem or the
slough backwater to the downstream extent of the tributary
plume (ADF&G 1981c).The tributary plume is clearwater which
extends downstream in the mainstem,side channel or slough
before mixing with the more turbid water.The extent of the
plume is influenced by both mainstem and tributary flows.At
higher mainstem flows,the plume is usually restricted.Depths
and velocities in the plume are a function of channel
morphology and mainstem stage.Physical characteristics and
fish utilization of tributary mouths are also influenced by the
type of confluences:tributary/slough,tributary/side channel
or tributary/mainstem (Sandone et al.1984).Water temperature
and water quality are those of the tributary •
5.3.1 Adult Salmon
Tributaries serve as the primary spawning habitat for chinook,
coho and pink salmon (Barrett et al.1984,1985).About
one-third of the chum salmon escapement upstream of Talkeetna
spawned in tributaries during 1984 (Barrett et al.1985).
Tributaries are rarely used by adult sockeye salmon (Barrettet
al.1984,1985).
The peak counts in tributaries upstream of RM 98.6 for 1981
through 1984 are summarized below:
135
r-In 1984,about 70 percent of all spawning salmon upstream of
RN 98.6 (68,742 fish)spawned in tributaries (Barrett et ale
1985).
All five salmon species spawned in tributary mouth habitat in
1984 (Barrett et ale 1985).Sockeye salmon spawning is limited
in this habitat type (Barrett et ale 1985).In contrast,
chinook,pink,chum and coho salmon frequently spawned in
tributary mouths in 1984 (Barrett et ale 1985).I Index counts
of spawning salmon in tributary mouth habitats are unavailable,
as counts are included in tributary counts.It appears that
more spawning occurs in tributaries than in tributary mouths
(Barrett et ale 1985).Water depth and velocity may limit
spawning in tributary mouths (Sandone et ale 1984).-
5.3.2 Juvenile Salmon
The significance of tributary and tributary mouth habitats for
,-juvenile salmon in the Talkeetna-to-Devil Canyon reach
(RN 98.6-152)is discussed below.
Sockeye Juvenile sockeye utilize tributary habitat
incidentally (Schmidt et al.1984).In 1983,few juvenile
sockeye were captured in tributary habitat (Figure 23).
.....
-
Chum -Tributaries likely provide rearing habitat for chum
salmon for about one to three months (Schmidt et a1.
136
-
-
.-
1984).Tributaries upstream of RM 98.6 that are natal
areas for juvenile chum are listed in Table 13.
Coho -Tributaries serve as the primary coho natal areas
upstream of RM 98.6.Some ~uvenile coho use tributaries
for rearing throughout the summer,while others redistri-
bute downstream from areas of emergence to other rearing
habitats,including tributary mouths (Schmidt et ale
1984)•This redistribution occurs throughout the summer
as fish become more mobile.Tributary mouths apparently
provide important rearing areas for age 0+coho (ADF&G
1981b,1983b).Some of the larger tributaries,such as
Indian River and Portage Creek,likely provide
overwintering habitat for juvenile coho.
Pink -Tributaries upstream of RM 98.6 are the primary
natal areas for pink salmon (Barrett et ale 1984,1985).
However,the extent of tributary utilization by juvenile
pink is limited because they move downstream to the ocean
shortly after emergence (Schmidt et ale 1984).
Chinook -Tributaries are important rearing areas for
chinook in the spring and early summer (Schmidt et ale
1984)•The redistribution of some juveniles from
tributaries to other rearing habitat,inclUding the
mainstem,sloughs and tributary mouths,occurs throughout
the summer (Schmidt et ale 1984)•Tributary·mouths
apparently are important rearing areas for juvenile
chinook.Tributaries,such as Indian River and Portage
Creek,are likely utilized by juvenile chinook for
overwintering.
5.3.3 Resident Species
In the Talkeetna-to-Devil Canyon reach,tributaries are th'e
primary spawning and rearing areas for rainbow trout and Arctic
137
-~
~-
-
~,
grayling (Schmidt et ale 1984).The larger tributaries in this
reach,such as Portage Creek,may provide overwintering habitat
for some rainbow trout and Arctic grayling (Schmidt et al.
1984).However,it appears that overwintering in tributaries
is limited (Sc1).midt et ale 1984).
Round whitefish,humpback whitefish,Dolly Varden and longnose
suckers likely spawn in tributary or tributary mouth habitats
(ADF&G 1983b,Schmidt et al.1984).Juvenile Dolly Va=den are
thought to rear in the upper reaches of tributaries (Schmidt et
al.1984).Tributary mouths are important rearing and feeding
areas for many resident species,such as rainbow trout,Arctic
grayling and whitefish (ADF&G 1981d,1983b;Schmidt et al.
1984).
138
6.0 FACTORS AFFECTING PRODUCTION
Each life stage of fish has factors that may limit production.
Some of these factors are complex and the mechanisms are not
easily understood (e.g.,the relationships among food
availability,growth,and survival).In contrast,other
factors are readily defined,such as freezing of redds causing
direct mortality.Although biological organisms have the
ability to adj ust and adapt to various environmental
conditions,overall they may not be highly successful.For
example,survival of salmon eggs from deposition to fry
emergence may be 5 percent or less under natural conditions.
In contrast,survival rates of 95 percent.or greater occur
frequently under artificially controlled conditions (e.g.
hatchery or laboratory conditions)that exclude many of the
limiting factors.Following is a summary of the major limiting
factors that may affect the.freshwater phases of anadromous
salmonids in the Susitna River.Although specific studies may
not have identified some of these as factors :Ln the Susitna
River,they have been described in other similar river systems.
_6.1 ADULT SALMON
When adult salmon enter the Susitna River,several potential
situations can prevent them from successfully spawning.These
include:-
(i)Sport Fishing -sportfish harvests remove fish from
the system.The primary fishing effort in the
susitna River is for chinook and coho salmon.The
effect of sport fishing is most evident on the coho
salmon run.In 1983,almost one of every five coho
entering the Susitna River was caught by an angler
(Table 3).The extent of harvest is governed by
regulations,water conditions,access to fishing
sites,etc.
139
(ii)Predation -in areas where salmon are available,
predators can remove adults prior to spawning.
Alaska Department of Fish and Game personnel (1984a)
have noted predation by bears,otter,weasels and
eagles in the Susitna River,but this removal of fish
is unquantified.Predation by animals is probably
less significant than the effects of sport fishing.
(iii)Access -barriers to upstream ~igration such as Devil
Canyon,impassable reaches in sloughs during low flow
conditions and beaver dams can prevent fish from
reaching spawning areas.It is unknown if this
precludes successful spawning.Salmon strandings in
passage reaches of sloughs,which can result in
mortality,have been noted (Barrett et a1.1984).
Additional factors such as high or low temperature extremes,
low dissolved oxygen,and turbid waters have been implicated as
potential factors limiting upstream migration,(Reiser and
Bjornn 1979).However,these have not been shown to prevent
successful migration in the Susitna River,probably because the
adults are exposed to ranges of these factors that are within
their range of tolerance.other factors such as high flows
have been shown to result in cessation of upstream movement
(Barrett et a1.1984,1985)(Figures 13, 15, 17, 19,21),but
movement does resume following these events and fish do
successfully·move to their spawning sites.Therefore,
mortality associated with high flow events is likely not a
significant factor.
6.2 SPAWNING AND INCUBATION
Each species within the Susitna Basin characteristically tends
to utilize specific areas for spawning (see Section 4.1).The
lack of a particular type of area can limit production for a
specific species.
140
-
~,..
-
(v)Upwelling Certain species,particularly chum
salmon,seek areas of groundwater upwelling for
spawning and incubation (Vincent-Lang et ale 1984,
Barrett et ale 1985).These areas offer potential
temperature and flow benefits.Because upwelling
areas often support maj or spawning ,it is assumed
that areas lacking upwelling would likely limit the
spawning and incubation success of species like chum
salmon.
(vi)Predation -Sculpins and other fish species such as
Dolly Varden and rainbow trout have been implicated
as taking significant numbers of salmon eggs.For
example,Hunter (1959)found that,with pink and chum
fry,the mortality from predation could range from 23
to 86 percent.Predation on salmon eggs and embryos
in the Susitna River has not been quantified.
(vii)Low Streamflow -Low water can dewater spawning areas
and expose incubating eggs and alevins {McNeil 1969).
Reduced winter flows may cause significant mortality,
if adult fish spawned under high water conditions and
redds were located along the margins.This may have
occurred during 1982 spawning and 1982-1983
incubation periods (Schmidt et al.1984).The
occurrence of groundwater upwelling may reduce
mortalities in areas of upwelling when natural flows
in the Susitna River are lower during the winter.
(viii)High Streamflow -Extremely high flows can scour
redd~'and destroy eggs and alevins.High scouring
flows are uncommon in fall and winter in the Susitna
River.Thus,scouring is probably not an important
limiting factor.
142
,~
l~
i~,
(ix)Freezing If redds are frozen,mortalities will
occur.Alevins may be able to move through the
gravel to avoid adverse conditions.Freezing of
redds is associated with low streamflows and
sub-freezing temper2'tures;these conditions occur
annually in the Susitna River.However,mortality
due to frozen redds is unquantified in the Susitna
River.Dependence on upwelling areas by adult salmon
may reduce embryo losses due to freezing.
(x)Sedimentation -An influx of fine sediments can shut
off the water flow through the substrate and result
in increased mortality.Sedimentation of spawning
areas in sloughs and side channels by high mainstem
discharge,ice processes and local flows occur in the
Susitna River.During spring breakup in 1982,
Slough 9 suffered a heavy influx of silts and sands,
reducing the amount of usable spawning habitat (ADF&G
1983a).
(xi)Intraspecific Competition -Adult salmon of the same
species may compete for specific spawning areas if
the density of spawning adults is high.Competition
for redd sites can lead to superimposition of redds
(the excavation of existing redds).Based on egg
retention studies,Barrett et al . (1984)concluded
that the adult salmon density was not excessive for
chum salmon in slough habitats in 1983.
(xii)Interspecific Competition -Adult salmon of two or
more species may compete for specific redd sites
(e.g.chum and sockeye may utilize similar spawning
habitats in sloughs).This can cause problems
similar to those for intraspecific competition.
143
I~
(xiii)Dissolved Oxygen -If sufficient dissolved oxygen is
not present,growth of embryos can be retarded and
mortality may occur.Dissolved oxygen is strongly
tied to permeability of gravels and intragrave1 flow.
Density of salmon eggs can also be a significant
factor.If only a few eggs are present,a given
level of dissolved oxygen,intragrave1 flow,and
substrate permeability may be sufficient.At higher
egg densities,this level might be insufficient and
would cause poorly developed fry or,in severe cases,
mortality.Studies by ADF&G (1983a)have indicated
that dissolved oxygen levels in the Susitna River are
generally not a problem for incubating embryos.
(xiv)Ice Processes -In certain instances,staging due to
ice cover can raise the level of the river diverting
cold mainstem water (ooe)into sloughs that are
predominantly supplied by warmer upwelling water
(e.g.Slough 8A in 1982-1983;ADF&G 1983a).This can
lead to reduced intragrave1 water temperatures,which
can delay embryo development or cause mortality.
6.3 REARING
Factors that limit the rearing phase of sa1monids are complex
and vary with species,size,and time of year.These factors
may affect species fo~only a short period of time (e.g.,pink
salmon fry may only be in freshwater for a few days before they
outmigrate)or for more than a year (e.g.chinook,coho or
sockeye juveniles).Following is a brief summary of the major
factors that affect rearing fish:
(i)primary and secondary production -the amount of
available food at specific times of ,the year can be
144
critical to assuring the growth and survival of
rearing fish.In the Susitna River,the highly
turbid water in the ice-free season reduces light
penetration and primary production;primary and
secondary production in the winter may be severely
restricted by the ice cover and low levels of light.
These,in turn,can severely reduce secondary
production and potential sources of fish food from
within the system (a~tochthonous production).The
extent of either autochthonous or allochthonous (food
sources from outside the system such as insects that
fall into the water)food production in the Susitna
River is presently unknown,although a study is
currently underway to determine primary productivity
relationships.Nutrients that support primary
production may not be limiting in the Susitna River:
extensive blooms of benthic algae have been noted
during brief clear-water periods that occur prior to
freeze-up.
(ii)Water Velocity -This factor is important both for
allowing production of food organisms and for
optimization of energy expenditures by fish.For
example,fish will seek areas in which they do not
have to needlessly expend energy.Low to moderate
stream gradients and water velocities generally are
considered productive juvenile rearing habitat
(Canada Fisheries and Oceans 1980).Peak flow events
that affect mainstem rearing areas may cause a
downstream displacement of juvenile chinook (Schmidt
et al.1984).
(iii)Water Depth -Small fish appear to utilize shallower
areas with greater frequency.Unless too shallow to
allow free movement,depth does not usually cause
mortality in the Susitna River.Juvenile fish
utilize water depth for cover in some situations.
145
--
I,\
(iv)Substrate The number of benthic invertebrates
generally decreases in the progression of rubble to
bedrock to gravel to sand (Reiser and Bjornn 1979).
This affects fish food production.Substrate also
provides cover for juveniles and areas of decreased
velocity.Cementing of interstitial spaces in
mainstem and side channel substrates likely reduces
their utility to rearing juveniles.
(v)Water Quality Temperature,dissolved oxygen,
turbidity,pH and other water quality parameters can
all limit production if they are not within a
specific range.Even with this range,an optimum may
not be available under natural conditions (e.g.an
optimum temperature for growth of salmonids may be
around 1So C,but temperatures do not reach this level
in the Susitna).
(vi)Cover Juvenile salmonids require,cover that
provides protection from predators.Cover can
include turbid water,vegetation,substrate and
depth.Large substrates and turbidity commonly
provide cover in mainstem and side channel habitats.
Vegetation and organic debris provide cover in upland
and side slough habitats.
The .end result of exposure to limiting factors in any system is
the number of fish that are able to survive and reproduce.The
on-going studies to document the fish resources and habitats of
the Susitna River are designed to establish these numbers.
146
ACKNOWLEDGEMENTS
Funding for this report was provided by the State of Alaska,
Alaska Power Authority.
The draft of this report was completed when the author was
employed by Woodward-Clyde Consultants.Two subsequent
editions,the draft final and final reports,were done by the
author as an employee of Entrix,.Inc.In the draft final and
final reports,substantial revisions and additions were made:
information on 1984 adult anadromous escapement monitoring was
added,as were the sections on resident species,Bering cisco
and eulachon.
The assistance of Don Beyer,Harza-Ebasco Susitna Joint
Venture,in preparing the sections on incubation and factors
affecting production is greatly appreciated.
Thanks is extended to Rhonda Steward of Entrix,Irc.for typing
the many drafts of the manuscript,and Andrea Shoulders and
Emily Berry of Woodward-Clyde Consultants for drafting and
preparing the figures.
Staff of the following proj ect participants provided helpful
review comments:
Alaska Department of Fish and Game,Su Hydro
Alaska Power Authority
Arctic Environmental Information and Data Center
E.Woody Trihey and Associates
Harza-Ebasco Susitna Joint venture
R&M Consultants
Woodward-Clyde Consultants
147
LITERATURE CITED
Acres American.1983a.FERC application for license for major
project:Susitna Hydroelectric Project,Initial statement
Exhibit A,C,and D.Prepared for Alaska Power
Authority,Anchorage,AK.Volume 1:189 pp.
Acres American.1983b.FERC license application for major
proj ect:Susitna Hydroelectric Proj ect,Exhibit E.
Prepared for Alaska Power Authority,Anchorage,AK.
Volume 6A:Chapter 3.603 pp.
Alaska Department of Fish
Salmon Status Report.
Juneau,Alaska.
and Game.1972.Cook Inlet King
Alaska Department of Fish and Game.
Alaska Department of Fish and Game.1978.Preliminary
environmental assessment of hydroelectric development on
the Susitna River.Prepared for the u.s.Fish and
I
-Wildlife Service.Anchorage,AX.207 pp.
Alaska Department of Fish
juvenile chinook and
Delaney and Roger
Anchorage,AX.
and Game.1979.Little Susitna
coho salmon study.Prepared by
Wadman,Division of Sport
River
Kevin
Fish.
1981b.Susitna Hydro
Draft Report:Juvenile
lower Susitna River.
Buffalo,NY.121 pp.
Alaska Department of Fish and Game.
Aquatic Studies -Phase I Final
anadromous fisheries project.
American,Inc.BUffalo,NY.
Alaska Department of Fish and Game.
Aquatic Studies -Phase I Final
anadromous fish study on the
Prepared for Acres American,Inc.
148
1981a.Susitna .Hydro
Draft Report:Adul t
Prepared for Acres
149
Alaska Department of Fish and Game.1982a.Susitna Hydro
Aquatic Studies -Phase II Final Data Report:Volume 2.
Adult anadromous fish studies.Anchorage,AX.239 pp.
Alaska Department of Fish and Game.1981e.Susitna Hydro
Aquatic Studies Phase I Report:Resident fish
investigations on the Upper Susitna River.Prepared for
Acres American,Inc.Buffalo,NY.137 pp.
susitna Hydro
winter aquatic
Anchorage,AI<.
Game.1983a.
Data Report:
May,1983),
Alaska Department of Fish and
Aquatic Studies -Phase II
studies (October,1982
137 pp.
Alaska Department of Fish and Game.1983b.Susitna Hydro
Aquatic Studies.Phase II Basic Data Report.Volume 3:
Resident and juvenile anadromous fish studies below Devil
Canyon,1982.Anchorage,AX.277 pp.
Alaska Department of Fish and Game.1983c.Susitna Hydro
Aquatic Studies -Phase II Report:Summarization of
Volumes 2,3,41 Parts I and II,and 5 -Su Hydro Basic
Data Reports,1982.Anchorage,AX.126 pp.
Alaska Department of Fish and Game.1981d.Susitna Hydro
Aquatic Studies -Phase I Final Draft Report:Resident
fish investigations on the Lower Susitna River.Prepared
for Acres American,Inc.Buffalo,NY.166 pp.
Alaska Department of Fish and Game.1981c.Susitna Hydro
Aquatic Studies Phase I Report (Vol.1):Aquatic
habitat and instream flow project.Prepared for Acres
American,Inc.Buffalo,NY.260 pp.
-
-
..-
Alaska Department of Fish and Game.1983d.Susitna Hydro
Aquatic studies,Phase II Report:Synopsis of the 1982
aquatic studies and analysis of fish and habitat
relationships.Anchorage,AX.152 pp.
Alaska Department of Fish and Game.1983e.Susitna Hydro
Aquatic Studies:Phase II Basic Data Report.Volume 4:
Aquatic habitat and instream flow studies,1982.Part I
and II,Anchorage,AX.367 pp.
Alaska Department of Fish and Game.1984.Tyonek subsistence
salmon fishery,1983.Prepared by James Browning,
Division of Commercial Fisheries.Soldotna,Alaska.
Alaska Power Authority.1984.Comments on the FERC Draft
Environmental Impact Statement of May 1984.Volume 9,
Appendix VII -Slough Geohydrology Studies.Anchorage,
AX.
Arctic Environmental Information and Data Center.1984.
Assessment of the effects of the proposed Susitna
hydroelectric project on instream temperature and fishery
resources in the watana to Talkeetna reach,Alaska Power
Authority.
Barrett,B.M.,F.M.Thompson,and S.N.Wick.1984.Report No.
1:Adult anadromous fish investigations (May -October
1983).susitna Hydro Aquatic Studies.Alaska Department
of Fish and Game.Anchorage,AX.380 pp.
Barrett,B.M.,F.M.Thompson,and S.N.Wick.1985.Report No .
1:Adul t anadromous fish investigations (May -October
1984).Draft.susitna Hydro Aquatic Studies.Alaska
Department of Fish and Game.Anchorage,AX.177 pp.and
appendices.
150
Bell,M.C.1973.Fisheries Handbook of Engineering
~Requirements and Biological criteria (Revised 1980).
Prepared for Fisheries-Engineering Research Program,Corps
of Engineers,North Pacific Division.Portland,Oregon.
Brannon,E.L.1965.The influence of physical factors on the
development and weight of sockeye salmon embryos and
a1evins.Int.Pac.Salmon Fish Comm.Prog.Rep.No.12.
26 pp.
""""Canada Fisheries and Oceans.1980.Stream Enhancement Guide.
I
Vancouver,B.C.82 pp •.
Combs,B.D.and R.E.Burrows.1957.Threshold temperatures for
the normal development of chinook salmon eggs.Prog.Fish
CUlt.19(1):3-6.
Delaney,X.,K.Hepler,X.Roth.1981.Deshka River Chinook
and coho Salmon StUdy.ADF&G Federal ,Aid in Fish
Restoration.Volume 22.AFS 49 - 1 &2.
Dong,J .N.1981.Thermal tolerance and rate of development of
coho salmon embryos.Master's Thesis.University of
Washington.
,jIl1#I1!A.
Florey,X.1984.ADF&G Commercial Fisheries.
Alaska.Personal Communication.
Anchorage,
Graybill,J.P.,R.L.Burgner,J.C.Gislason,P.E.HUffman,X.H.
Wyman,R.G.Gibbons,R.W.Kurko,Q.J.Stober,T.W.Fagnan,
A.P.Stayman and O.M.Eggers.1979.Assessment of the
reservoir-related effects of the Skagit project on
downstream fishery resources of the Skagit River,
Washington.University of Washington,College of
Fisheries,Cont.No.FRI-OW-7905.
151
Hale,S.S.1981.Freshwater habitat relationships -chum salmon
f""'"(Oncorhynchus ~).Alaska Dept.of Fish and Game,
Habitat Division,Anchoraqe,Ak.
-Harza-Ebasco susitna Joint Venture.19P4.Reservoir and River
Sedimentation.Final Report.Prepared for the Alaska
Power Authority.Anchoraqe,AK.
Hunter,J.G.1959.Survival and production of pink and chum
salmon in a coastal stream.Journal Fish.Res.Bd.Can.
16(6):835-886.
-
McNeil,W.J.1969.Survival of pink and chum salmon eqgs and
a1evins..In:SYmposium on Salmon and Trout in Stream.
Edited by T.G.Northcote,Institute of Fisheries,
University of British Columbia,Canada.pp.101-116.
McNeil,W.J.and J.E.Bailey.1975.Salmon rancher's manual.
National Marine Fisheries Service,Auke Bay Alaska,
Fisheries Laboratory.National Oceanic and Atmospheric
Administration.
Mills,M.J.1979.
ADF&G Federal
SW-I.
Alaska statewide sport Fish Harvest StUdies.
Aid in Fish Restoration.Volume 20.F-9-11,
-
Mills,M.J.1980.Alaska statewide sport Fish Harvest Studies.
1980.Alaska Department of Fish and Game.Federal Aid in
Fish Restoration.Volume 21.F-9-12,SW-I.65 p.
Mills,M.J.1981.Alaska statewide sport Fish Harvest S~udies
1980 Data.ADF&G Federal Aid in Fish Restoration.
Volume 22.F-9-13,SW-I.
152
Mills,M.J.1982.Alaska statewide Sport Fish Harvest Studies.
I"""ADF&G Federal Aid in Fish Restoration.Volume 23.
F-9-14,SW-I.
Mills,M.J.1983.A1a~ka statewide Sport Fish Harvest Studies:
ADF&G Federal Aid in Fish Restoration.Volume 24.SW-I.
Mills,M.J.1984.Alaska statewide Harvest Studies.ADF&G
Federal Aid in Fish Restoration.Volume 25.SW-IA.
-
Morrow,J.E.1980.The Freshwater Fishes of Alaska.Alaska
Northwest Publishing Company.Anchorage,Alaska.
Neilson,J.D.and G.H.Geen.1981.Enumeration of
salmon from spawner residence time and aerial
Transactions of the American Fisheries
110(4):554-556.
spawning
counts.
Society.
R&M consultants,Inc.1982.Susitna
Tributary Stability Analysis.
American,Inc.BUffalo,NY.33 pp.
Hydroelec~ric Project:
Prepared for Acres
+attachments.
R&M consultants,Inc.1984.Susitna River Ice study,1982-1983.
Prepared for Alaska Power Authority •Anchorage,Alaska.
136 pp.+appendices.
Reiser,D.W.and T.C.Bjornn.
range land management on
western United States and
of anadromous salmonids.
Rept.PNW-96.54 pp.
1979.Influence of forest and
anadromous fish habitat in the
Canada.1.Habitat requirements
USDA Forest Service Gen.Tech.
Sandone,G.,D.Vincent-Lang,and A.Hoffman.1984.Chapter 8:
Evaluations of Chum Salmon-Spawning Habitat in Selected
Tributary-Mouth Habitats of the Middle Susitna River.In
Report No.3:Aquatic habitat and instream flow
153
-
investigations (May-October 1983),by C.Estes and D.
Vincent-Lang,eds.Susitna Hydro Aquatic Studies.Alaska
Department of Fish and Game.Anchorage,AK.70 pp.
Sautner,J.S.,and M.E.Stratton.1984.Chapter 1:Access and
Transmission Corridor Studies.In Report No.4:Access
and transmission corridor investigations (July -October
1983),by D.schmidt,C.Estes,D.Crawford and D.
Vincent-Lang,eds.Susitna Hydro Aquatic Studies.Alaska
Department of Fish and Game.Anchorage,AK.89 pp.
Sautner,J.S.,L.J.Vining,and L.A.Rundquist.1984.Chapter
6:An Evaluation of Passage Conditions for Adult Salmon
in Sloughs and Side Channels of the Middle Susitna River.
In Report No.3:Aquatic habitat and instream flow
investigations (May-October 1983),by C.Estes and D.
Vincent-Lang,eds.susitna Hydro Aquatic Studies.Alaska
Department of Fish and Game.Anchorage,AK.70 pp.and
appendices.
Schmidt,D.,S.Hale,D.CraWford,and P.Suchanek,eds.1984.
Report No.2:Resident and juvenile anadromous fish
investigations (MaY-October 1983).Susitna Hydro Aquatic
Studies.Alaska Department of Fish and Game.Anchorage,
AK.395 pp.
and E.J.
Volume 19.
Canada.
-scott,W.B.
Canada.
Ottawa,
Crossman.1973.Freshwater Fishes of
Fisheries Research Board of Canada
-
stober,-Q.J.,S.C.Crumley,D.E.Fast and E.S.Killebrew.1982.
Effects of hydroelectric discharge fluctuation on salmon
and steelhead in the Skagit River,washington.University
of Washington,College of Fisheries Conts.No.
FRI-OW-8218.
154
Trihey,E.W.1983.Preliminary assessment of access by spawning
salmon into Portage Creek and Indian River.Prepared for
Alaska Power Authority,Anchorage,AK.31 pp.
-
Trihey,E.W.~982.Preliminary assessment of access by
salmon to side slough habitat above Talkeetna.
for Acres American,Inc.Buffalo,NY.26 pp.
spawning
Prepared
-
Vincent-Lang,D.,A.Hoffman,A.Bingham,C.Estes,D.
Hilliard,C.Steward,E.Trihey and S.Crumley.1984.
Chapter 7:An Evaluation of Chum and Sockeye Salmon
ppawning Habitat in Sloughs and Side Channels of the
Middle Susitna River.In Report No.3:Aquatic habitat
and instream flow investigations (May -October 1983),by
C.Estes and D.Vincent-Lang,eds.susitn~Hydro Aquatic
Studies.Alaska Department of Fish and Game.Anchorage,
AK.178 pp.
Vincent-Lang,D.,and I.Queral.1984.Chapter 5:Eulachon
I
Spawning Habitat in the Lower Susitna River.In Report
No.3:Aquatic habitat and instream flow investigations
(May -October 1983),by C.Estes and D.Vincent-Lang,
eds.Susitna Hydro Aquatic Studies.Alaska Department of
Fish and Game.Anchorage,AK.32 pp.and appendix.
Wangaard,D.and C.Burger.1983.Effects of various water
temperature regimes on the egg and alevin incubation of
Susitna River chum and sockeye salmon.U.S•Fish and
Wildlife service,National Fishery Research Center,
Anchorage,Alaska.
155
APPENDICES
APPENDIX A -ADF&G Susitna Hydro Reference List in
chronological Order
1.
2.
Barrett,B.M.1974.An assessment of the anadromous fish
populations in the upper Susitna River watershed
between Devil Canyon and the Chulitna River.
Division of Commercial Fisheries,Alaska Department
of Fish and Game,Anchorage,AK.57 pp.
Friese,N.V.1975.Preauthorization assessment of
anadromous fish popUlations of the upper Susitna
River watershed in the vicinity of the proposed Devil
Canyon Hydroelectric project.Division of Commercial
Fisheries,Alaska Department of Fish and Game.
Anchorage,AX.108 pp.
3.Alaska Department of Fish and Game.1977.Corps of
Engineers Susitna River Hydroelectric Project:
Baseline inventory study (~July ~976-30 September
~976).Prepared for u.S.Department of the Interior,
Fish and wildlife Service,Anchorage,AX.9~pp.
4.
5.
Riis,J.e.1977.Preauthorization Assessment of the
Susitna River Hydroelectric Project:Preliminary
investigations of water quality and aquatic species
c.omposition.sport Fish Division,Alaska Department
of Fish and Game.Anchorage,AX.50 pp.
Alaska Department of Fish and Game.1978.PrC'liminary
environmental assessment of hydroelectric development
on the Susitna River.Prepared for the u.S.Fish and
Wildlife Service.Anchorage,AX.207 pp.
~56
.-.
6.Alaska Department of Fish and Game.
Aquatic Studies -Phase I Final
anadromous fisheries project.
American,Inc.Buffalo,NY •
1981.Susitna
Draft Report:
Prepared for
Hydro
Adult
Acres
7.Alaska Department of Fish and Game.1981.Susitna Hydro
Aquatic Studies -Phase I Report:Resident fish
investigation on the Upper Susitna River.Prepared
for Acres American,Inc.Buffalo,NY.137 pp.
8.Alaska Department of Fish and Game.1981.
Aquatic Studies Phase I Final
Resident fish investigation on the
River.Prepared for Acres American,
NY.166 pp.
susitna Hydro
Draft Report:
lower Susitna
Inc.BUffalo,
9.Alaska Department of Fish and Game.1981.Susitna Hydro
Aquatic Studies -Phase I Report:Juvenile anadromous
fish study on the Lower Susitna River.Prepared for
I
Acres American,Inc.Buffalo,NY.121 pp.
10.Alaska Department of Fish and Game.1981.Susitna Hydro
,Aquatic Studies -Phase I Report (Vol.1):Aquatic
habitat and instream flow proj ect.Prepared for
Acres American,Inc.Buffalo,NY.260 pp.
11.Alaska Department of Fish and Game.19a1.Susitna Hydro
Aquatic Studies -Phase I Report (Vol.2 pt.1):
Aquatic habitat and instream flow project.Prepared
for Acres American,Inc.Buffalo,NY.305 pp.
12.Alaska Department of Fish and Game.1981.Susitna Hydro
Aquatic Studies -Phase I Report (Vol.2 Pt.2):
Aquatic habitat and Instream Flow Project.Prepared
for Acres American,Inc.Buffalo,NY.541 pp.
157
-
-
".....
-
13.Alaska Department of Fish and Game.1982.Susitna Hydro
Aquatic Studies -Phase I Report:Aquatic Studies
Program.Prepared for Acres American,Inc.Buffalo,
NY.137 pp.
14.Alaska Department of Fish and Game.1982.Susitna Hydro
Aquatic Studies -Phase II Final Data Report:Volume
2.Adult Anadromous Fish studies.Anchorage,AK.
239 pp.
15.Alaska Department of Fish and Game.1982.Susitna Hydro
Aquatic Studies -Phase II Report:Volume 2:Adult
Anadromous Fish StUdies,Part B:Appendices A-H.
Anchorage,AK.318 pp.
16.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies -Phase II Report:Summarization of
Volumes 2,3,4:Parts I and II,and 5 -SU Hydro
Basic Data Reports,1982.Prepared fo~Alaska Power
Authority,Anchoraqe,AK.126 pp.
17.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies Phase II Data Report:Winter
aquatic studies (October,1982 May,1983),
Anchorage,AK.137 pp.
18.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic studies,·Phase II Report:Synopsis of the
1982 aquatic studies and analysis of fish and habitat
relationships.Anchorage,Ak.152 pp.
19.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies -Phase II Report:Synopsis of the
1982 aquatic studies and analysis of fish and habitat
relationships.Appendices A-K.Anchoraqe,AK.
357 pp.
158
20.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic studies.Phase II Basic Data Report.
Volume 3:Resident and juvenile anadromous fish
studies below Devil Canyon,1982.277 pp.
21.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies.Phase II Basic Data Report.
Volume 3:Resident and juvenile anadromous fish
studies below Devil Canyon,1982 (Appendices).
22.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies :Phase II Basic Data Report.
Volume 4:Aquatic habitat and instream flow studies,
1982,Part I and II.367 pp.
23.Alaska Department of Fish and
Aquatic Studies.Phase
Volume 4:Aquatic habitat
1982,Appendix A (Draft).
Game.1983.Susitna Hydro
II Basic Data Report.
and instream flow studies,
Anchorage,~.182 pp.
-
-
-
24.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies:Phase II Basic Data Report.
Volume 4:Aquatic habitat and instream flow studies,
1982,Appendix B (Draft).Anchorage,AX.99 pp.
25.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies:Phase II Basic Data Report.
Volume 4:Aquatic habitat and instream flow studies,
1982,Appendix C (Draft).Anchorage,AX.221 pp.
26.Alaska Dep~rtment of Fish and Gam~.1983.Susitna Hydro
Aquatic Studies:Phase II Basic Data Report.
Volume 4:Aquatic habitat and instream flow studies,
1982,Appendices D and E (Draft).Anchorage,AK.
168 pp.
159
27.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies:Phase II Basic Data Report.
Volume 4:Aquatic habitat and instream flow studies,
1982,Appendices F-J (Draft)•Anchorage,AK.
236 pp.
28.Alaska Department of Fish and Game.1983.Susitna Hydro
Aquatic Studies Phase II Basic Data Report.
Volume 5:Upper Susitna River impoundment studies,
1982.Anchorage,AX.150 pp.
29.Barrick,L.,B.Kepshire and G.CUnningham.1983.Upper
Susitna River Salmon Enhancement Study.Division of
Fisheries Rehabilitation,Enhancement and
Development,Alaska Department of Fish and Game.
Anchorage,AX.15 pp.
30.Barrett,B.M.,F.M.Thompson,and S.N.wick.1984.
Report No.1:Adult anadromous fish inyestigations
(May-october 1983).Susitna Hydro Aquatic Studies.
Alaska Department of Fish and Game.Anchorage,AK.
380 pp.
31.Schmidt,D.,S.Hale,D.Crawford,and P.Suchanek,eds.
1984.Report No.2:Resident and juvenile
anadromous fish investigations (May-october 1983).
Susitna Hydro Aquatic Studies.Alaska Department of
Fish and Game.Anchorage,AX..395 pp.
32.Quane,T.,P.Morrow,and T.Withrow.1984.Chapter 1:
Staqe and Discharge Investiqations.In Report No.3:
Aquatic habitat and instream flow investigations
(May-October 1983),by C.Estes and D.Vincent-Lang,
eds.Susitna Hydro Aquatic stUdies.Alaska
Department of Fish and Game.Anchoraqe,AK.1.36 pp.
and appendices.
1.60
:~
-
--
I~
33.Quane,T.,I.Queral,T.Keklak,and D.Scagven.1984.
Chapter 2:Channel Geometry Investigations of the
Susitna River Basin.In Report No.3:Aquatic
habitat and instream flow investigations (May-October
1983),by C.Estes and D.Vincent-Lang,ed~.Susitna
Hydro Aquatic Studies.Alaska Department of Fish and
Game.Anchorage,AX.81 pp.and appendices.
34.Keklak,T.and T.Quane.1984.Chapter 3:continuous
Water Temperature Investigations.In Report No.3:
Aquatic habitat and instream flow investigations
(May-October 1983),by C.Estes and D.Vincent-Lang,
eds.susitna Hydro Aquatic Studies.Alaska
Department of Fish and Game.Anchorage,AX.112 pp.
and appendices.
35.Sandone,G.and T.Quane.1984.Chapter 4:Water
Quality Investigations.In Report No.3:Aquatic
habitat and instream flow investigations (May-October
I
1983),by C.Estes and D.Vincent-Lang,eds.Susitna
Hydro Aquatic Studies.Alaska Department of Fish and
Game.Anchorage,AX.30 pp.and appendices.
36.Vincent-Lang,D.and I.Queral.1984.Chapter 5:
Eulachon spawn~ng Habitat in the Lower Susitna River.
In Report No.3:Aquatic habitat and instream flow
investigations (May-October 1983),by C.Estes and D.
Vincent-Lang,eds.Susitna Hydro Aquatic Studies.
Alaska Department of Fish and Game.Anchorage,AK.
32 pp.and appendix.
37.sautner,J.S.,L.J.Vining,and L.A.Rundquist.1984.
Chapter 6:An Evaluation of Passage Conditions for
Adult Salmon in Sloughs and Side Channels of the
Middle Susitna River.In Report No.3:Aquatic
habitat and instream flow investigations (May-october
161
1983),by C.Estes and
Hydro Aquatic Studies.
Game.Anchorage,AI{.
D.Vincent-Lang,eds.Susitna
Alaska Department of Fish and
70 pp.and appendices.
-
..-
38.Vincent-Lang,D.,A.Hoffman,A.Bingham,C.Estes,D.
Hilliard,C.Stewart,E.Trihey,and S.Crumley.
1984.Chapter 7:An Evaluation of Chum and Sockeye
Salmon spawning Habitat in Sloughs and Side Channels
of the Middle Susitna River.In Report No.3:
Aquatic habitat and instream flow investigations
(May-October ~983),by C.Estes and D.Vincent-Lang,
eds.Susitna Hydro Aquatic studies.Alaska
Department of Fish and Game.Anchorage,AK.178 pp.
39.Sandone,G.,D.Vincent-Lanq,and A.Hoffman.~984.
Chapter 8:Evaluations of Chum Salmon-Spawninq
Habitat in Selected Tributary-Mouth Habitats of the
Middle susitna River.In Report No.3:Aquatic
habitat and instream flow investigation~(May-october
1983),by C.Estes and D.Vincent-Lang,eds.susitna
Hydro Aquatic Studies.Alaska Department of Fish and
Game.Anchorage,AI{.70 pp.
40.Vincent-Lang,D.,A.Hoffman,A.Binqham,and C.Estes.
~984.Chapter 9:Habitat suitability criteria for
Chinook,Coho,and pink Salmon Spawning in
Tributaries of the Middle susitna River.In Report
No.3:Aquatic habitat and instream flow
investigations (May-October 1983),by C.Estes and D.
Vincnet-Lang,eds.Susitna Hydro Aquatic Studies.
Alaska Department of Fish and Game.Anchorage,AX.
61 pp.and appendices •
41.Sandone,G.and C.Estes.1984.Chapter ~o:Evaluations
of the Effectiveness of Applying Infrared Thermal
Imagery Techniques to Detect Upwelling Groundwater.
162
-
-
~-
I~
In Report No.3:Aquatic habitat and instream flow
investigations,by C.Estes and D.Vincent-Lang,eds.
Susitna Hydro Aquatic Studies.Alaska Department of
Fish and Game.Anchorage,AK.27 pp.
42.Sautner,J.S.and M.E.Stratton.1984.Chapter 1:
Access and Transmission Corridor Studies.In Report
No.4:Access and transmission corridor
investigations (July-October 1983),by D.Schmidt,C.
Estes,D.Crawford and D.Vincent-Lang,eds.susitna
Hydro Aquatic Studies.Alaska Department of Fish and
Game.Anchorage,AK.89 pp.
43.Schmidt.D.C.and M.E.Stratton.1984.Chapter 2:
Population Dynamics of Arctic Grayling in the Upper
Susitna Basin.In Report No.4:Access and
transmission corridor investigations (July-October
1983),by D.Schmidt,C.Estes,D.Crawford and D.
Vincent-Lang,eds.susitna Hydro Aquattc Studies.
Alaska Department of Fish and Game.Anchorage,AK.
26 pp.
44.Alaska Department of Fish and Game.1984.Susitna Hydro
Aquatic Studies:Procedures Manual,May 1983 -June
1984.prepared for Alaska Power Authority,
Anchorage,AK.255 pp.
45.Alaska Department of Fish and Game.1984 .Susitna Hydro
Aquatic Studies:Procedures Manual,May 1983 -June
1984.(Appendices).Prepared.for Alaska Power
Authority,Anchorage,Ak.119 pp.
46.Barrett,B.M.,F.M.Thompson,and S.N.wick.1985.
~Report No.1:Adult anadromous fish investigations
(May-October 1984).Draft.Susitna Hydro Aquatic
t-Studies.Alaska Department of Fish and Game.
Anchorage,AK.177 pp.and appendices.
.-.163