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Home My WebLink AboutAPA1611JAY S.HAMMOND,BOVERNOR l'h1l\~~ January 19,1976 / ~lT&V[@IF fA\~&~~~\/ I DEPARTMENT OF FISII AND GAME / !333 RASPBERRY ROAD ANCHORAGE 99502 Mr.Gordon Watson Fish and Wildlife Service U.S.Department of the Interior 813 II St reet Anchorage,Alaska 99501 Dear t,lr.Watson: Contained herein are reports suhmitted by the Alaska Department of Fish and Game to fulfill contract obligations to the U.S.Pish and Wildlife Service for studies of the proposed Susitna River hydroelectric proj ect. The biological studies attached were conducted by three separate divisions of this agency,resulting in a segmented report.The Game Division conducted studies of moose and caribou within and adjacent to the impoundment area.The Commercial Fish Division studied primarily the anac1romous fish populations and aquatic habitat downstream of the proposed impoundment site,and the Sport Fish Division conducted a limnological study supplemented with fishery information for both resident and anadromous fish species. The full impacts of hydroelectric development of the Susitna River are as yet undetermined.The potential impacts depicted in each of the fish division report segments are not necessarily impacts this project will have,but illustrate areas of biological concern.As stated previously, inadequate funding and time have been limiting factors in carrying out more extensive studies, We think the collective findings of these reports will be valuable as preliminary baseline data and as an aid in planning future investigations. - If I may be of assistance in interpreting or clarifying any of the attached study findings feel free to contact me. Y07 trUlY,"/! //_ ~t~l \j'./,p/'~~------ Larry J.Heckart rvlgt-Research Coordinator Division of Sport Fish Attachments: ARLIS A!ask:::;Resources Lit ,Cln '\i IntormatJon SerVices \nrhnrage.Alaska - - - - - - - PREAUTHORIZATION ASSESSr1ENT OF ANADRJrl0US FISH POPULATIONS OF THE UPPER SUSITNA RIVER WATERSHED IN TIE VICINITY OF THE PROPOSED DEVIL CANYON HYDROELECTRIC PROJECT by: Nancy V.Friese Fisheries Research Biologist Alaska Department of Fish and Game Division of Commercial Fisheries Anchorage,Alaska November,1975 ARLIS Alaska Resources Library &Information Services Anchorage.tUaska TABLE OF CONTENTS List of Tabl es 0 oii i .i~ - Li st of Fi gures Introduction.0 Description of Study Area Methods of Investigation Sampling Procedures Winter Sampling Spring Sampling SUl11T1er Sampling Laboratory Analyses . Results .... .... . . . . . ...'..... . . ... .... v 1 2 2 2 2 6 6 8 8 -Adult Investigations Rearing Fry and Escapement Investigations Susitna River Winter Sampling Susitna River Summer and Fall Surveys Escapement Surveys .0 ..·0 ·8 16 16 22 .·.·29 -Talkeetna and Chulitna River Investigations Climatological Observations Discussion and Summary ........ . •32 35 3S Potential Impacts and Recommendations Acknowledgements Literature Cited Ii • •..•• 0 •42 ·48 •49 j I Maps of sioughs and clearwater streams on the Susitna,Talkeetna and Chul i tna Rivers . . . . . • . . •.•. • • . . . . . .SO ARLIS Alaska Resources Library &Information Services }\nchorage,AJaska Appendixes: - Appendixes (cont.) ...'.- TABLE OF CONTENTS (cont.) .'".",.. II Escapement surveys of sloughs and tributary streams of the Susitna River tributaries and Talkeetna River.. . . . . . . .93 II I Notes on the more common benthi c i iwertebriltes found in the Susitna River tributaries . . . . . . . . . . . . . . . . . .IDS IV Estimated monetary values of the Susitna River salmon stocks 107 ~. 11 :'- - .-. - LIST OF TABLES Table - - - 1 2 3 East bank fishwhee1 catch of salmon by species from July 7 through AU9ust 27,Devil IS Canyon Project,1975 . . • . • . .9 West ba~k fishwhee1 catch of salmon from July 9 through July 31, Devil's Canyon Project,1975 ..••....•.•.•......10 Number of tagged fish submitted into the salmon populations and the nUmJ2r of tagged to untagged fish observed on the spawning grounds with the resultant population estimates by species,Devi1's Canyon Proj2:t,1975 . • . . . . . • • • . . . . . . • . . . . . .14 Record of tagged salmon recovered below the Devil Canyon camp,Devi1's Canyon Project,1975 .......•... Analysis of chum salmon age and sex data by percent from ment samples collected at fishwheel camp,Devil IS Canyon 1975 .. .. .. ... .... . .... . . ......... .... .'II •.. fi sh\'/hEe 1... ..15 escape- Project,... ..17 -10 Analysis of sockeye salmon age and sex data by percent from escape- ment samples collected at fishwheel camp,Devi1's Canyon Project, 1975 It J7 Analysis of pink salmon sex data by percent from escapement samp1es collected at fish\'/heel camp,Devi1 1 s Canyon Project,1975 ....17 Survey of winter conditions and fry distr-ibution in slough numbers 8 through 21,Devi1's Canyon Project,1974-1975 20 Age,length and weight analysis of coho fry collected in the Susitna River and sloughs numbers,8A through 21,Devi1 1 s Canyon Winter Project,1974-75 .....•....•.......'.. . . . . .23 Survey of winter conditions in Indian River,Lane Creek and Gold Creek,Devi1's Canyon Winter Project,1974-75 24 - - 11 Analysis of water conditions at Chase Creek,Devil's Canyo~Project, 1974-1975 ..........•..•..•.....•.....25 12 Analysis of water conditions at Gold Creek,Devi1's Canyon Project, 1974-1975 ..................•.........25 13 Analysis of water conditions at the Anchorage-Fairbanks Highway Bridge crossing,Devil 's Canyon Project,1974-1975 26 14 Age and length samples of coho fry collected at sloughs numbers 1 through 21 and Fishwhee1 Slough,Susitna River,Devi1's Canyon Project,1975 .................•••....•.27 15 Age and length samples of coho fry collected at Whisker's,Chase Lane and McKenzie Creeks,Susitna River,Devil's Canyon Project, 1~75 .... .. ...... .. .. .. ..•..28 iii LIST OF TABLES (cant.) Table ... Stomach content analysis of coho salmon fry collected in sloUQhs numbers 9,11 and 15,Susitna River,and slough number 2,Talkeetna River,Devil 's Canyon Project,1975 . . . . . . . . . . . .30 16 17 Age and length samples of king salmon fry in slough number 15, Susitna River,Devil IS Canyon Project,1975 .28 - 18 Peak adult escapement survey counts for chum,pink,sockeye and king salmon,Susitna River,Devil 's Canyon Project,1975 31 19 Age and 1ength samp 1es of chum sa 1mon fry from slough m~mber 1, Beaver Pond Slough,and slough number 4,Talkeetna River,Devil's Canyon Project,1975 . . . . . . . . . . . . . . . . . . . . ...33 20 Age and length of coho salmon fry from slough numbers 1,2,Beaver Pond,Billion,3A,5,6, 7,Wi,iskey and 9,Talkeetna River,Devil's Canyon Project,1975 . . . . . . . . . . . . . . . . . . .34 21 Analysis of water conditions of the Talkeetna River at the Alaska Railroad bridge,Devil's Canyon Project,1975 . . . . . . . . .36 22 Climatological Observations at the fishwheel camp,Devil Canyon Project,1975 . . . . . . . . . . . . . . . . . . . . . . . . .37 iv - - LIST OF FIGURES Figure - 1 2 Devil Canyon iA reference to the Susitna River water~hed and northern Cook Inlet,Devil 's Canyon Project,1975 Map of the upper Susitna River stucy area encompassed in the Devi1's Canyon Project,1975 . . . ...•. 3 4 3 Map of the Talkeetna River study area encompassed in the Devil's Canyon Project,1975 . 5 4 Average hourly catch of pink and chum salmon per day from the east bank fishwhee1,Devi1's Canyon Project,1975 ..11 5 Average hourly catch of sockeye salmon from the east bank fishwhee1 at the Devil 's Canyon fishwhee1 camp,Devi1's Canyon Project,1975 . . . ... . . . . . . . . . ...12 6 Reference map of the downstream recovery areas for salmon tagged at the fishwhee1 site,Devil IS Canyon Project,1975 15 7 8 Length frequency of the co~o salmon catch from the east and west bank fishwhee1s,Devi1's Canyon Project,·1975 length frequency of the chum salmon catch from the east and west bank fishwhee1s,Devi1's Canyon Project,1975 18 18 9 - Length frequency of the sockeye salmon catch from the east and west bank fishwhee1s,Devi1's Canyon Project,1975 19 10.Length frequency of the pink salmon catch from the east and west bank fishwhee1s,Devi1's Canyon Project,1975 19 11 Water temperature profiles recorded daily in the Susitna River at Gold Creek,Devi1's Canyon Winter Project,1975 38 12 Profile of water and air temperatures recorded daily (2000 hours)at the east bank fishwhee1 cam~.Devil 's Canyon Project,1975 . . . . . . . . • . . . . . . . . . . . . . .39 v - - - - A 1972 Senate Public Works Committee resolution requested the U.S. Corps of Engineers to consider the possibilities of hydroelectric power development along the Upper Susitna River in the area of Devil Canyon. In 1974 the National t1arine Fisheries Service (N~~FS)contracted the Alaska Department of Fish and Game,Division of Commercial Fisheries, to conduct a preauthorization assessment of the salmon populations (OncQrhynchus ~.)utilizing the Susitna River in the vicinity of the proposed Devil Canyon damsite.The objectives of these studies were to determine the spawninq distribution,relative abundance,migrational timing,representative age-length-sex composition by species,and juvenile rearinq areas (Barrett,1974,1975a,1975b,1975c).Investiga- tions were exoanded in 1975 to include the lower reaches of the Talkeetna and'Chulitna Rivers through funds provided by U.S.Fish and Wildlife Service. Several sites within the Susitna River drainaqe have been under consideration for construction of a hydroelectric complex since the early 1950's.The current recommended plan includes the construction of dams and powerp1ants on the Susitna River at Devil Canyon and Watana and electric transmission facilities to the Alaska Rai1be1t load centers. Construction is expected to commence in 1981 with Watana Dam followed by Devi 1 Canyon Dam.Prorosed construction time for the project is 12 years. The proposed plan for the Watana site includes the construction of an earthfi11 dam with a structural height of 810 feet (247 m)at river mile 165 (266 km).The reservoir would have an elevation of 2,200 feet (671 m)and a crest elevation of 2,2lO feet (674 m).It I,,,ould cover a surface area of approximately 43,000 acres and extend about 54 river miles (87 km)upstream from the damsite,i.e.,4 miles (6 km)above the confluence of the Susitna and Oshetna Rivers (personal communication, J.Reid,1975). The p1 ans for the Devil Canyon site i ncl ude the constructi on of a concrete thin-arch dam with a structural heiqht of 635 feet (194 m) located at river mile 134 (216 km).The reservoir created would have a surface area of about 7,550 acres and would extend upstream approximately 23 river miles (37 km)to the Watana Dam site (personal communication, J.Reid,1975). Barrett's studies (1974)provide the only recent information avail- able on the extent of salmon utilizing the Susitna River and its tributaries between Devil Canyon and its confluence with the Chulitna River.Investi- gations by U.S.Fish and Wildlife Service in 1956 documented the presence of salmonid populations in the Susitna River and four tributary streams between Gold Creek and the Devil Canyon site (Anonymous,1957).Anadromous species were not found above Devil Canyon. This study included continued monitorinq of spawning distribution, relative abundance and representative aqe-length-sex composition by'species and surveys of juvenile rearinq areas.Reconnaissance surveys were initiated on the Tal keetna and Chul i tna Rivers in June 1975 and weekly surveys \>Iere conducted from July through September 1975.Adult and juvenile fish popu- lations \~ere monitored in the Susitna River and its tributaries between Devil Canyon and its confluence with the Chulitna River from July through September 1975. Description of Study Area The Susitna River rises in Alaska Range of southcentra1 Alaska and drains an area exceeding 19.000 square miles (49.210 sq km).The Susitna River is approximately 275 miles (443 km)long from its source to its point of discharge into Cook Inlet (Fiqure l).The major tributaries of lower basin originate in glaciers and carry a heavy load of glacial silt.:1ost of the tributaries are turbulent in their upper reaches and slow-flowing in the lower regions.Thirty-seven sampling sites were monitored on the Susitna River between Devil Canyon and the confluence of the Chulitna River in 1975 (Figure 2).Twenty-eight of these sites were clearwater slough areas adjunct to the Susitna Piver.The remaininq locations were clearwater creeks and rivers flowing into the Susitna ~iver ~Appendix I.Figures 1-27}. The Talkeetna River originates in the Talkeetna '1ountains and flows in a westerly direction to its point of discharge into the Susitna River 80 miles (129 km)upstream from its mouth.An aerial reconnaissance of the river was conducted in June 1975.Potential spawning and rearing areas were mapped and later surveys by riverboat established 16 sampling sites from Clear Creek downstream to the confluence of the Talkeetna and Susitna Rivers (Figure 3).Two of these sites are clean1ater streams and 14 are slough areas adjunct to the Talkeetna River (Appendix I.Figures 28-40). The Chulitna River originates in the Alaska Range and flows in a southerly direction.joining the Susitna River opposite the Talkeetna River confluence.The braided nature of this river at its mouth prevents exten- sive surveying by riverboat.One sampling location was established on the Chulitna River approximately one-half mile (0.3 m)above its confluence with the Susitna River (Appendix I,Figure 41). r1ETHODS OF INVESTIGATION Sampling Procedures l~inter Sampling Winter sampling was conducted from a base camp located at Indian River. Access to slough areas was provided by a sinqle track snow vehicle.Fifteen sloughs and 3 clearwater streams were surveyed from March 11 to March 14, 1975.Sloughs were sampled for temperature,dissolved oxygen,pH,relative water height and flow,ice cover and thickness,and snow depth.Dissolved oxygen was measured with a Edmondson-Hil son D.O.and temperature analyzer (Model #60-620).Fry were sampled from sloughs 11ith minnow traps when water depths permitted.Samples caught were frozen and returned to the Anchorage laboratory for analysis.Standard lenqth (SL)data was obtained for all specimens.Scale samples were taken for age analysis. A Ryan thermograph was installed at Gold Creek (river mile 119)to monitor daily water temperature fluctuations.Water conditions at Gold Creek and the Anchorage-Fairbanks Highway Bridge crossing below Talkeetna were monitored biweekly.Water conditions at Chase Creek,river mile 91 (146 km).were sampled monthly.Two liter water samples were collected at each site for total dissolved solid analysis.Temperature,dissolved oxygen, pH,water depth,ice cover and snow cover were recorded at each site. 2 - - - .WiUow •Palmer N ,20 miles Figure i.Devil Canyon in reference to the Susitna River watershed and northern Cook Inlet t Devil's Canyon Project t 1975. 3 Portage Cr. ... - - .' N Cr. Talkeetna R. Cr. Indion R. ~.8A nO.SB nO.A nO.Se 'no.SD Clear Cr. Fourth of July Cr. To Ikeetna ~ cc--"5o Figure 2.Map of the uoper Susitna River study area encomoassed in the Devil IS Canyon Project,1975.- - - - - - - - - Figu~e 3. -_..SL no.5 TALK EETNA Map of the Talkeetna River study area encomnassed in the Devi1's Canyon Project,1975. 5 \ WhiskeYSI. Spring Sampling A base camp was established on Billion Slough at the confluence of the Susitna and Talkeetna Rivers June 2,1975.Surveys by riverboat were con- ducted on the Talkeetna,Chulitna,and Susitna (from Talkeetna downstream to the Anchorage-Fairbanks Highway bridge crossing)Rivers to investigate potential adult spawning areas and locate areas utilized by rearing fry. High water conditions during this period made surveying difficult and in some areas impossible.Slough areas were identified and mapped where the mainstem river was not flowing through them.Permanent depth stakes were installed.Fry samples were taken with a dip net or minnow seine and pre- served in 10 percent formalin solution. Two liter water samples were taken in the Talkeetna River at the Alaska Railroad bridge and the Susitna River at the Anchorage-Fairbanks Highway bridge biweekly.Air and water temperature and depth were taken when possible.Samples were processed in the Anchorage laboratory for total dis- solved solids. An aerial survey of the area was conducted June 26,1975.Additional slough areas were noted. Summer Sampling Fishwheels were operated on the Susitna River from July 7 through August 27,1975 at the same locations as 1974 studies.One wheel was located adja- cent to the east bank of the river approximately 5 miles (8 m)upstream from the town of Talkeetna;the second was located adjacent to the west bank of the river approximately 2.3 miles (3.7 m)downstream from the first.Fish- wheels were operated on a twenty-four hour a day schedule with exception of occational breakdown periods.The east and west bank fishwheels averaged 2.25 and 2.5 revolutions per minute,respectively,during the season.Fish- wheels were normally fished 2 feet (0.6 m)above the river bottom due to daily fluctuation of water levels.Fishwheel design is discussed by Barrett (1974).Complete structural failure of the west bank fishwheel axel occurred on August 1.Fishwheel sampling at this site was discontinued due to the low catch prior to the breakdown.~ill net sets were made on the west bank approximately 100 yards (91 m)above the fishwheel site to continue monitor- ing salmon migration. Fishwheel catches were recorded daily by species and all salmon were tagged immediately below their dorsal fin with a color and number coded 1 inch (2.54 cm)diameter Peterson disc.Buffer discs were also applied. Length and sex data were collected on all species of salmon.Scale samples for age analysis were taken on all species with the exception of pink salmon (Q.gorbuscha).Fish were measured from mid-eye to fork of tail.Fish were released immediately after sampling. A stream survey camp was established July 17 and maintained through September 27 at the mouth of Gold Creek.Boat,foot,and aerial surveys monitoring spawning and rearing areas between Devil Canyon and the con- fluence of the Susitna and Chulitna Rivers and the Talkeetna River were 6 - ... - - - - - - .- - conducted.All spawning and rearing areas were scheduled to be surveyed weekly,but due to poor weather,substandard survey conditions,and the distance involved in surveying,a strict schedule could not be adhered to.The section of the Susitna River from the cormnunity of Chase down- stream to the Chulitna River and the one accessible slough on the Chulitna River was surveyed by the crew stationed at the fishwhee1 camp. Sloughs were surveyed in their entirety.Streams were surveyed within established index areas,usually located from the mouth upstream 0.5 mile (0.8 km).Limited manpower did not permit surveying the streams in their entirety,although adults do occur above most established index areas. Water and air temperature,survey conditions as determined by the survey crew,and water depth were recorded on each slough survey.Stream flow was taken on limited streams with a flow rod. A two man crew conducted escapement surveys in streams and sloughs; one person counted live fish while the other individual counted carcasses. Tagged fish observed were recorded by tag color and,when permissab1e,by tag number.Sampling adult salmon for age and length in the spawning areas was discontinued in 1975 due to the condition of the scales.Most scales sampled were reabsorbed and accurate age determination could not be made. Rearing fry data was collected in sloughs of the Susitna,Talkeetna and Chulitna Rivers.The total number of fry observed was recorded and species composition noted.A dip net and/or minnow seine was employed to capture fry for positive species identification,age-length composition samples and foregut analysis. Biweekly water samples were collected from three locations for total dissolved solid content.The Susitna River was sampled at Gold Creek and Anchorage-Fairbanks Highway bridge below Talkeetna.The Talkeetna River was sampled at the Alaska Railroad bridge above the confluence of the Susitna River.Air and water temperatures were recorded. Benthic invertebrates were collected with artificial substrates.The artificial substrates consisted of a wire vegetable basket lined with nylon cloth with 210 micrometer ~m)mesh and filled with rocks collected from the streambed sampled.Four traps were installed in Indian River and Water- fall Creek.Four types of habitat were sampled in Indian River.These included a deep pool,deep riffle,shallow riffle and quiet water.Two traps were placed in a shallow riffle and two in a shallow pool near the mouth of Waterfall Creek.The substrate was placed in a bucket immediately after retrieval.Specimens were preserved in 70 percent methyl alcohol. Insects were identified to the generic level in most cases with the aid of a Bausch and Lomb dissecting scope. Juvenile insects are often good indicators of water conditions,i.e., dissolved oxygen and temperature.Many groups are extremely sensitive to even slight changes in temperature.A temperature change of 5°C could result in the elimination of certain insect populations within slough areas,re- sulting in a complete change in the food chain. 7 Climatological observations were recorded daily at the fishwheel camp. Conditions monitored included air and water temperature,relative water level and general atmospheric conditions,such as cloud cover and precipitation. Laboratory Analyses Total dissolved solids were determined by methods adapted from Stand- ard Methods (APHA,et.al.,1971).The water sample was shaken vigorously for a minimum of 15 seconds and then 1000 milliliters (ml)was poured into a graduated cylinder and allowed to settle for a 24 hour period.After settlinq,the water was filtered through preweighed 1.2 ~(0.0012 mrn) Millipore filters.The first few hundred ml were filtered taking care not to disturb the residue of the sample.The volume of water filtered was recorded.The remainder of the sample was filtered through a second r~i11ipore filter,using distilled water to completely rinse the residue from the graduated cylinder. r1illipore filters were placed in Petri dishes and dried in a drying oven at 103-105°C until constant weights were attained.The settlable and nonfilterable residue weights were computed by determining the dif- ference between the weights of the filters before and after filtration. Total suspended solids (mg/l)are the summation of the settlable and non- filterable residues. Age data presented in this report is expressed by the European method. The number of winters spent in freshwater is written to the left of the decimal.The number of winters reared in saltwater appears to the right of the decimal. RESULTS Adult Investigations A total of 618 salmon (Oncorh~ncus iQ.)were captured in the two fish- wheels from July 7 through August',1975.The composition by species was 291 pink (.Q..gorbuscha),139 chum (0.keta),27 coho m.kisutch), 103 sockeye UL.nerka}and 58 king salmon (0.tShaw~tscha).The catch of the east bank f;shwheel comprised 98.7 percent 0 the total catch for the season.The west bank fishwheel was removed from the water on August 1.Limited gill netting was initiated on the west bank of the river at that time.Sampling on the west bank indicated only a minor portion of the fish migrate along this bank.Catch of the east and west bank fish- wheels by species and date is presented in Tables 1 and 2,respectively. Average hourly catch of pink and chum salmon is presented in Figure 4. The chum salmon fishwheel catches peaked on August 14.Fishwheel catches indicate about 70.5 percent of the chum salmon migration occurred between August 5 and August 15.Approximately 69 percent of the pink salmon migra- tion occurred during the 9 day period between August 1 and August 9.Sock- eye salmon catch was significantly higher than that of 1974.About 48.5 percent of the migration occurred between August 2 and August 10 (Figure 5). The accumulative catch of coho salmon shows a marked decline over 1974. About 52 percent of the coho catch occurred from August 12 through August 8 - - ... - - - - - Table 1.East bank fishwhee1 catch of salmon by speoies from July 7 through August 27, Devil 's Canyon Project,1975. Date No.Hours Pink Chum Coho Sockeye King Fished Da;1y Cum Da;1y Cum Dai 1y Cum Da;1y Cum Da;1y Cum July 57240 0 0 0 0 0 0 0 5 8 24 0 0 0 0 0 0 0 0 3 8 9 24 0 0 0 0 0 0 0 0 6 14 10 24 0 0 0 0 0 0 0 0 4-18 11 24 0 0 0 0 0 0 0 0 4 22 12 24 0 0 0 0 0 0 0 0 0 22 13 24 0 0 0 0 0 0 0 0 2 24 14 24 0 0 0 0 0 0 0 0 2 26 15 24 0 0 0 0 0 0 0 0 4 30 16 24 0 0 0 0 0 0 0 0 2 32 .~.17 24 0 0 0 0 0 0 0 0 2 34 18 24 0 0 0 0 0 0 0 0 2 36 19 24 0 0 0 0 0 0 0 0 1 37 20 24 0 0 0 0 0 0 0 0 0 37 21 24 0 0 0 0 0 0 1 1 0 37 22 24 0 0 0 0 0 0 1 2 0 37 23 24 1 1 0 0 0 0 3 5 1 38 24 24 4 5 0 0 0 0 1 6 0 38 25 24 6 11 0 0 0 0 1 7 0 38 26 24 13 24 0 0 0 0 4 11 1 39 27 24 9 33 0 0 0 0 1 12 2 41 28 24 7 40 1 1 0 0 6 18 2 43 29 24 14 54 0 1 1 1 5 23 1 44 30 20.0 5 59 0 1 0 1 0 23 0 44 31 0 0 59 0 1 0 1 0 23 0 44 August 1 2.5 13 72 0 1 0 1 0 23 0 44 2 24 46 118 5 6 1 2 10 33 1 45 3 24 36 154 9 15 0 2 4 37 0 45-4 24 31 185 1 16 0 2 6 43 0 45 5 24 32 217 10 26 2 4 9 52 0 45 6 24 17 234 14 40 0 4 4 56 0 45 7 24 11 245 2 42 2 6 3 59 0 45 8 24 8 253 7 49 3 9 2 61 0 45 9 24 8 261 2 51 0 9 5 66 0 45 10 24 4 265 9 60 0 9 7 73 0 45 11 24 2 267 8 68 0 9 3 76 1 46 12 24 6 273 10 78 0 9 2 78 0 46 13 24 6 279 12 90 3 12 3 81 0 46 14 24 4 283 15 105 0 12 2 83 0 46 15 24 2 285 9 114 3 15 4 87 1 47 16 24 0 285 2 116 2 17 0 87 2 4917'24 1 286 1 117 1 18 0 87 0 49 18 24 0 286 1 118 1 19 5 92 1 50 19 24 1 287 3 121 0 19 0 92 1 51-20 24 0 287 8 129 3 22 4 96 0 51 21 24 1 288 1 130 1 23 1 97 1 52 22 24 0 288 4 134 1 24 2 99 0 52 23 24 0 288 2 136 1 25 2 101 1 53-24 24 0 288 1 137 1 26 2 103 0 532524028801370260103053 26 24 0 288 0 137 0 26 0 103 0 53 27 24 0 288 2 139 1 27 0 103 0 53 Season Total 1198.5 288 139 27 103 53 9 ... Table 2.West bank fishwhee1 catch of salmon from July 9 through July 31.Devi1's Canyon Project,1975... No.Pink Chum Coho Sockeye King Date·Hours Fished Daily Cum Daily Cum Daily Cum Daily Cum Daily Cum - July 9 22 0 0 0 0 0 0 0 0 0 0 -10 24 0 0 0 0 0 0 0 0 2 2 11 24 0 0 0 0 0 0 0 0 0 2 12 24 0 0 0 0 0 0 0 0 1 3 13 24 0 0 0 O'0 0 0 0 0 3 -14 24 0 0 0 0 0 0 0 0 0 3 15 24 0 0 0 0 0 0 0 0 0 3 16 24 0 0 0 O.0 0 0 0 0 3 17 24 0 0 0 0 0 0 0 0 1 4 .... 18 24 0 0 0 0 0 0 0 0 1 5 19 2 0 0 0 0 0 0 0 0 0 5 20 21 0 0 0 0 0 0 0 0 0 5 21 24 0 0 0 0 0 0 0 0 0 5 -22 24 0 0 0 0 0 0 0 0 0 5 23 24 1 1 0 0 0 0 0 0 0 5 24 24 0 1 0 0 0 0 0 0 0 5 25 24 0 1 0 0 0 0 0 0 0 5 ,;. 26 24 1 2 0 0 0 0 0 0 0 5 27 24 1 3 0 0 0 0 0 0 0 5 28 24 0 3 0 0 0 0 0 0 0 5 29 24 0 3 0 0 0 0 0 0 0 5 30 24 0 3 0 0 0 0 C 0 0 5 31 24 0 3 0 0 0 0 0 0 0 5 Season -Total 549 3 0 0 0 5 - ... - 10 !.~I(5.2)/.;,~,...pink'.,"I", \1\/ \I";:J.......Y......;-----.chum,..1\I \I \,\/\r..../ \,\\\\8101214161820 222426August,~I ,/,r ,", ,I\ , ,/\,,'\'li't/\'//\,,//".,,I7 91113'15 17 192123 2527 29312 4 6JulyI--'I--'2.22.01.81.6~1.40.r::~~1.2z:~~1.00.80.60.40.2Figure4.Averagehourlycatchofpink(Oncorhynchusgorbuscha)andchum(~.ketalsalmonperdayfromtheeastbankfishwheel,DevillsCanyonProject,1975. ,0.5':,-•.....II0.4II•It-o::::Jo0• 00;::I:~0.3c...cu~I"'•(.)I1\., \I\I \f-'0.2f\)I••V\••~.,~1\I\/•.-..-..212325272931246 810121416 182022242628JulyAugustFigure5.Averagehourlycatchofsockeyesalmonfromtheeastbankfishwhee1attheDevi1'sCanyonf;shwhee1camp.Devil·s.CanyonProject.1975.ltt•,I,If• 24,1974.The peak in migration may have occurred after removal of the fishwhee1s in 1975,but escapement surveys of coho salmon were also signifi- cantly less in 1975.The peak king salmon migration occurred prior to in- stallation of the fishwhee1s and a steady decline in catch was observed a few days after operations began.Catch did increase over 1974,but this was due to earlier installation of fishwhee1s. Population estimates were obtained for pink,chum and sockeye sal- mon migrating into the Susitna River and susceptible to capture at the fishwhee1 sites by the Peterson mark and recapture formula (Table 3). The number of fish tagged in the population (m),number of fish sampled (c),and number of fish sampled (r),were used to calculate the estimated size of the population with 95 percent confidence limits using the fo110winq expressions: N =m c +N U~-m)~N-c ~ r -mc N-1 The population estimates for each species were as follows: Chum Pink Sockeye 11 ,850 +4,044 6,257 +"261 1 ,835 ~337 .- - The population estimates reflect the density of the salmon populations that were susceptible to capture at the fishwhee1 sites rather than the spawning ground density above the fishwhee1 sites.The number of live fish sampled were from sloughs and index areas of streams above the fishwhee1 sites surveyed by the escapement survey crew (Appendix II,Table 1). Insufficient numbers of coho salmon were observed to obtain population estimates for this species.The peak king salmon migration occurred prior to installation of fishwhee1s so population estimates based on catch and recovery data could not be determined . The population estimates would be increased directly proportional to possible tag loss and/or tag induced mortalities.The possibility of either of these having occurred above the fishwhee1 sites is unlikely since no tag scarred fish were observed on spawning grounds and tags were difficult to remove from carcasses.The population estimates contain some positive bias since these factors are not taken into consideration in the computati on. Sportfishermen provided tag recoveries from below the fishwhee1 camp (Table 4).This is concurrent with 1974 findings.Two possible implica- tions still exist:(1)a proportion of the tagged fish become disoriented after the capture-tag process and finally migrate downstream spawning in a different location than their homestream,or (2)fish passing the tagging site are not all destined for upstream areas and later migrate downstream to spawn in areas below the site.Further studies are needed to provide an explanation for this phenomenon.Either possibility adds bias to esti- mates of population size above the fishwhee1 sites. 13 Table 3.Number of fish tagged at the fishwheel site and the number of tagged to untagged fish observed on the spawning grounds with the resultant population estimates by species.D~wll·s Canyon Project.1975. ".. No.Fish No.Fish Sampled Population Species Tagged (m)(live counts)Estimates (Fishwhee1)Untagged Tagged (r)Total (c)(N) Chum 139 674 8 682 11850 +4044 Pink 291 943 46 989 6257 +261 Sockeye 103 370 22 392 1835 +337 14 - - - -~- - Table 4.Record of tagged salmon recovered below the Devil Canyon fishwheel camp,Devil's Canyon Project,1975. Species Tagging Date Recovered Date location Activity ~~S~~l~~~~:~~~~~~~~!~e~~~_~~~~~~~~~!~g _ Pink 7/27 8/3 Birch Creek__~~~~:~~1 ~~lZ ~!~~r_~r~~~_ Chum 8/12-8/14 8/17 Chunilna Creek Spawning 8/9-0/11 8/20 Montana Creek Spawning 8/9-8/11 Byers Creek________________~~lg:~~l~~~l~r~_~r~~~~~_- ~!~g !~Z:Z~lQ Z~l~~~~!~~~_~r~~~_ Coho 8/2 8/11 Birch Creek 8/5-8/7 8/23 Clear Creek 8/21-8/23 7/29 Cfear Creek------------------------------------------------------------------------------- - - - 5 miles Figure 6.Reference map of the downstream recovery areas for salmon tagged at the fish- wheel site,Devil 's Canyon Project,1975. heep Cr: 15 Analysis of chum salmon age samples revealed the 1975 escapement was composed of primarily three and four-year-old fish produced from the 1971 and 1972 brood year,respectively (Table 5).Eighty-two percent of the samples collected at the fishwheel camp were four-year-old fish.The sex ratio was 1 female to 1.1 males.Length frequency distribution for chum salmon is presented in Figure 8. Sockeye salmon sampled at the fishwheels were represented by five age classes produced from the 1970 through 1972 parent years (Table 6).The largest percentage of individuals (46.3 percent)spent one year in fresh- water and two years in the ocean prior to returning as adults to spawn. The sex ratio was 1.3 females to 1 male.Precocious males (1.1 age)com- prised 14.8 percent of the fish sampled.The mean length frequency of sockeye.including precocious males,was 511.7 mm (Figure 9). Pink salmon were not sampled for age composition.Sex composition and length frequency were recorded.The sex ratio was 2.1 females to male (Table 7).The mean length of pink salmon sampled was 445.8 mm (Figure 10). Escapement sampling of coho salmon for age was limited due to the small number of fish captured and condition of the scale samples.The prominent age class of the migrants was 2.1 or four-year-old fish from the 1971 brood year.Males comprised 48.3 percent of the samples.The 29 individuals sampled had a mean length of 522.1 mm (Figure 7). Rearing Fry and Escapement Investigations Susitna River Winter Samplinq Winter investigations were continued in March 1975 to monitor the di5tribution of rearing fry and winter conditions of the sloughs and main- stem Susitna River.Studies conducted during December,January and February established that coho fry were wintering in Sloughs Numbers 8-A,9.9-A, 11 and 19 (Barrett 1975a.1975b,1975c). All sloughs upstream from Slough Number 8 were monitored for winter conditions and fry distribution during March (Table 8).Sloughs surveyed had ice cover ranging from 25 to 100 percent.Minnow traps were installed in sloughs with sufficient water levels.Rearing fry were found in Sloughs 13,17 and 21.Dissolved oxygen was below minimum levels required for fish survival at all sampling locations.Data is presented in the report,al- though the proper functioning of the dissolved oxygen analyzer is in question. Slough Number 13 was 60 percent ice free and water temperature was 38°F. Minnow traps were fished for a 26 hour period.Seven 0.0 age class coho fry were captured (Table 8). Slough Number 21 had a 100 percent ice cover and water temoerature was 33°F.Minnow traps installed in the slough for a 21.4 hour period captured five 0.0 age coho fry (Table 8). 16 - - ... Table 5.Analysis of chum salmon age and sex data by percent from escapement samples collected at fishwheel camp.Devil's Canyon Project.1975. Yearof Return 1975 - Table 6. Year of Return 1975 ..... .... Age Class Brood Year Sample 0.2 0.3 0.4 1972 1971 1970 Size percent 16.4 82.0 1.6 16.4 82.0 1.6 100.0 number 21 105 2 21 105 2 128 Sex Ratio Sample Male Female Size percent 52.5 47.5 100 number 73 66 139 Analysis of sockeye salmon age and sex data by percent from escapement samples collected at fishwheel camp.Devil's Canyon Project.1975. Age Class Brood Year Sample 1.1 1.2 1.3 2.1 2.2 1972"1971 1970 Size percent 14.8 46.3 25.9 3.7 9.3 14.8 50.0 35.2 100.0 number 8 25 14 2 5 8 27 19 54 Sex Ratio Sample Male Female Size percent 43.3 56.7 100.0 number 42 55 .97 Table 7.Analysis of pink salmon sex data by percent from escapement samples collected at fishwheel camp.Devil '5 Canyon Project.1975. Year of Return Sex Ratio Male Female Sample Size - - - percent number 31.8 92 68.2 197 17 100.0 289 10 _. >,u 15 ..~.c:: QI 522.1:J X = 0-n =29QI ~ LL..... ~c::10cu 0 ~ QI ...'0. 5 I -430 440 450 460 470 480 490 500 510 520 530 540 550 560 570 580 590 600 length (r.1I11) figure 7.Length frequency of the coho salmon (Oncorhynchus kisutch)catch from the east and west bank fishwheels.Devil's Canyon Project.1975. 25 -' x =577 .5 20 n =139 .' >,uc 15CI.J :J 0- CI.J ~ lL. .....c 10CI.J U L CI.J -Q., 5 630 O-+---,.--,---.,----r--..,r---.,..--~-_r--r__-....__-_t"'------ 520 Figure 8.Length frequency of the chum salmon (0.ketal catch from the east and \'!est bank fish\-Iheels,Devil's Canyon-Project,1975. 18 - 10 x =511.7 n =97 ••.:t'.......,•• Figure 9. 350 400 450 500 550 length (rrn:l) Length frequency of the sockeye salmon catch from bank fishwhee1s,Devi1's Canyon Project,1975. 600 650 the east and west 22 26 x '"445.G n '"289 18 -16 ~14 c ClJ:scr ClJ 12L LL ~ C ClJ 10u ClJ L 0.. 8 6 "4 2 320 340 360 330 400 420 440 460 4GO 500 520 540 560 length (r.l:l) - Figure 10.Length frequency of the pink salmon catch from the east and west bank fishwhee1s,Devi1 1 s Canyon Project,1975. 19 .-•.........•._.._._------- Table8.SurveyofwinterconditionsandfrydistributioninSloughNumbers8,eA,9,9A,10,II,12,Dev11'sCanyonProject,1974·1975.RTnnow----rrapCatcllFish.SpedesTemperalureIceIceSr:owDepthWaterAnchorNumbert:'Ic:acSloughSurveyDateTime~D.O.pHThicknessCoverIniceDepthFlowIcehours-0-';,...c.No.SIte(ml1itary)rwater(ppm)(inches)(t)(inches)(1nches)Detectablepresentfished0c";.&:..-0....uuCJ'"'"8A1216/741530283513.65.10.3-0.5305-243.0yesno0.01113/75141563413.45.50.1-3750-124.5yesno0.02118175134430 368.85.40.1-3504-282.0yesno0.03114/75134530361.85.30.0-1250-34.0yesno0.0----...----------------------------------------------------------...-----_.._-----------.---_._--...------_.-------._-----------------_.._-------..SAA12/6/741200263412.85.40.5-1205-245.0vesno0.01117/7512102934----5.40.5-2806-124.0vesno68.100 002./17/75142025'338.55.80.5-4952-143.0vesno0.03/12/7515~532367.55.30.3-3400-62.5yesno0.0_.---_.----_.--.._----------------------------------.-.-------------------..------------_.-.----.---------.----------------------------------------SA812/5/751215263411.75.50.3-1201·247.0yesno0.01117/7512252934----5.40.3-1.8901-108.5yesno68.020 032/17175144824337.25.80.5-6992-304.5yesno21.80 00 03112175153032 3411.05.40.0-2602-183.5yesno0.0----_._----------------~-------.-._--------------.-------..._-....._.--.-.---..---_.._.__.._------------..-.---_._----------------_.__._.-.-----_..9A12/5/7509903034.11.05.52.0800-3616.5yesno25.540001/171751107253411.45.50.5-4952-3613.0yesno66.020002/17/7512452733'9.05.30.8-10951-309.5yesno0.03/13/751600303(j13.05.50.5-1600-46.5yesno0.0------_.------------------------_.---.._-----------------------------------.-----------------------------_..------------_._----_.---------.------_.P09B1215/741000303410.55.32.8805-217.3yesno25.56 00001/17/7511282533----5.50.2-3805-1513.0yesn"66.500002/17/75131526347.45.30.4-10955·1610.0yesno45.470 003/12/75122030331.q5.44.1)91)0-181i.0nono0.0.---.----------~~-----------------------------~-----------------------------------------------.---_.------._-._-------_._----.--------------------.9AA2117/7515452435.56.15.40.5·2652-59.5yesno20.32100 03113/75160030361.35.50.5-1600-46.5yesno0.0-------------------------.----------------.--------------------.------------_.~---------------------------------._-----------_._-------------.._---9,\83/13/75160030371.25.60.0-1800-18.5yes'no0.010A2117/7515152434.!l7.45.40.1-4553-166.ayesno0.0_________•____~_______ft.____________________________________________________•____________________•__.~______________________________.______________11A1214/74130015349.65.60.5801-214.5yesno43.52 0 001/1~/7514454357.05.70.5-3955-312.0yesno24.8101 02/13/i51025-6368.15.80.4-9950-0.320.0yesno24.50 0 0 03112/75H2O32369.56 00.1-3601-218.0yesno0.0_.____________________________•__•_______________________________________________________h______________________________~__________________________11812/4/741320-------------------_.._---~-yesno43.26 0001/14/7514304358.85.70.5-2.,5951-39.0yesno24.860002113/751100-2367.45.40.3-8950-0.314.0yesno68.52 0003/12/75143031379.55.90.1-3801-211.5yesno0.0______________•____________~______________________________________________._.___r____________________~_____________________________________________1281214/7413451532.5-----_.4.3.952-365.8noyes0.01/1':/7515154335.85.76.251003-24·8.0yesno0.02/13/7512300348.55.B0.5-2998-1B11.5yesno0.03/12/75150:)333414.55.80.0-2990-368.5yesno0.0------------_.-----~_._--_.~-_._------------.-------------.--------------._----------------------_.-------_.--------------------------_._-------_.-12C12/~/74l~OO.15345.25.80.1-29512.0yesno0.01/14/7515054346.85.60.1-3705-364.0yesn()0.0211317511553349.45.20.3-9981·244.5no no0.03/12/75i5103:!3618.05.90.0-13300-53.5yesno0.0,t12A12/4/74,13301532.55.06.04.6,95,7.8no•yes0.0ttt t))~:.JItTable8.SurveyofwinterconditionsandfrydistributionInSlougt,.•mtJers13. 14. 15.16,17. 18. 19.20.21.Oevtl'sCanyonProj!ct,1974-197~.(continutationpage2of2)..TemperatureIceIceSloughSurveyDateTime,oF)0.0.pHThicknessCove,'No.Slt~(military)Airllater(ppm)(Inches),~)Snol<DepthInIce(Inches)WaterAnchorNumberDepthflowIcehours(Inches)DetectablepresentfishedRlnno...,Tr4pCatchFts!!Species'"c:~"~0__.00.o>.c-..cIQ-:Io~40UUU"'"13A12/4/741/14/752/13/753/12/751440153113551520153383413431376.85.60.87.45.5"9.5-29.25.70.5-216.06.20.0-1959075503-481-120·100-241.93.54.01.5yesyesyesyesnononono0.00.00.00.0-----_._.._---_-_.-----_--_--_-----_._..__.._---_----_------_..-_..-_._-----_-.....•..-.---1)81214/7415001/14/7515412/13/7514203/12/7515351533834o3432385.2 5.61.07.05.60.5-4.59.25.60.5-217.05.90.29590754015-125-100-247.68.07.51.5yesyesyesyesnononono0.00.00.0.26.070 0----..------_---_..-..-_.._- -- -.._----_----_..-___--_.-..--..---.-__-------_-------.-14A12/5/74I/H/752/16/753/12/7515301105114013252534635163431.32.511.85.41.09.15.50.5-38.85.70.3-1013.55.30.3-1509890508-365-91-155-63.35.03.35.5yesyesyesyesnononono0.00.00.00.0-------..------------_..--_.._..------_- _..--.-.._...-----.-_.-_.-_a._._ -_oo-_••.__••_1481/14/752/16/753/12/7510351210131063516..3331358.25.52.5-59.75.70..3-31.75.33.51001001005-121-141-83.04.54.0yes_yesyesnonono0.00.00.0......--.-_....._----_....--.-...------..-_..--.-----.----_..---_...._....-.....-.•_._....oo.....-.._.-__...oo--.-.._.........__...._--....._...•••••_._15A12/4/7410003/12/"7512301028.33••_----'9.8••••5.4•22100100193-240.04.0nononono0.00.0••.....••••.-_--------------_-.-_-.__-.._..-- ---_..-_._..oo_.-_.__----_ _...••.---..-. . -----•••.__•.__•.._rI)f-'15812/(/741/15/752/15/753112/751015100012051240103~18329333234:2.45.29.06.45.4108.15.51211.85.50.3-5100100100901136-487-160-367.314.0,9.02.0yesnoyesnononono0.00.00.00.015C1/15/7509302/15/75123018348347.45.30.5-37.45.30.1-7951002-245-303.05.0yesnonono0.00.0--_-.__--_.----------._---.-.---_.._--;"'-----------..__..-..__--"'---..__-_____.._..--_-..--16A2117/75311217509421210262835336.55.20.5-212.05.30.5-12701001-181-123.05.0ye~nono?0.00.017A1116/7511.52113/7517003/11/7514002835-23326359.65.70.5-18.55.30.3-3'1.45.40.5-42095355-360-120-1210.513.06.5yesyesyesnonono0.023.50 0 0020.4300 01781116/752/13/753111/7511(517001410~834-336Z73610.25.70.28.35.50.3-41.45.50.0-51050408-240-80-363.04.02.5yesyesyesnonono0.00.018A1116/752114/753111175122510351330296283433.534.59.25.56.57.25.70.5-91.35.40.3-51001009512-240-280-246.06.57.3nonoye~nonono0.00.01919A2/16/753111/7583/11/751720130513001626253434349.05.50.5-61.35.40.3-21.45.60.3-298757514-28.0-120-209.518.017.0nOyesyesnonono16.6100 022.10 0 0 0..._---_-..-_..--.._-_.-_.:--_._--_-.-__._._..-----_.-----..__..-_.-_.._._..---------_----..---_-..--____..------_.._---.._-___.._..-.20A2116/751430173210.35.50.6-1510023-362.0yesno0.03/11/751130••.-._-----0.9-1210012-360.0noneyes0.0--_...._---_.........-......----..--_..--..._-...__..-...__.._.._........---_.....-.._-_.....-....__.--..---_.--------......_-...--_..--....._..-_.-------.._..._---_...._-............_--.....__.2082/16/7515301632.-.-5.41410023-369.0no no0.03/11/7511152432__a.5.724.5JOO12·102.5noneno-----------..-_---___._----_..--..--------------_._--_..-----_.___------_..---_.----._--_.21A2/16/75162017349.45.70.1-121005-105.0yesno0.03/11/75120024321.75.50.5-51000-2411.5yesno21.44 0 0---._"..--.-__..__-____..--_-----_.-_._..--__..--_..-_._-----.-----_..__.-----------___._-----_.---2182/16/7516351632.59.45.40.3-10'1005-168.5nono0.03111/751215243316.55.30.5-41000-249.5.yesno21.41 0 0 0.--------------'"-_-_-_._-_-_-__----.._._-__-_.._.--,.._--___-.---~-_.-. The mainstem Susitna River was sampled for rearing fry at three locations.A minno~1 trap installed in the mainstem river near Slough 17 captured 3 coho fry.There was a 35 percent ice cover at this location. One age 0.0 coho fry vias captured "in the mainstem Susitna River at Curry. This specimen was 69.0 mm in length,weighed 3.3 qm,and had a condition factor of 1.005 (Table 9). Twelve coho fry were captured in the mainstem Susitna River,2.5 river miles south of the Talkeetna River during ~pril.Age analysis revealed all were 0.0 age fish produced from the 1973 brood year.Mean length,weight and condition factor \'1ere 64.2 mm,2.7 gm and 1.020, respectively. Winter conditions were monitored on Indian river,Lane Creek and G01d Creek (Table 10).Water flow was noted in all three locations. Ice cover was 50 nercent in Lane Creek,95 percent in Gold Creek and 99.5 percent in Indian qiver.Water samples were taken at Gold Creek,Chase Creek,and the Anchorage-Fairbanks Highwav bridCle.Total suspended solid content decreased from the previous three months.Total suspended solid levels at Chase Creek were 4.0 mq/l (Table 11).The settleables,that portion of the total suspended solids which settle within a 24 hour period.comprised 50 percent of the sample.Ice cover was 100 percent and anchor ice was present on the stream bottom. Total dissolved solid levels averaged 6.5 and 3.5 mg/l at Gold Creek and the Anchorage-Fairbanks Highway bridge,respectively (Tables 12 and 13).The settleable portions were approximately 54 percent at Gold Creek and 71 percent at Anchorage-Fairbanks Hiqhw~y bridge.Dissolved D;t.","Jen levels averal'je5ppm higher at Gold Creek. Susitna River summer and fall surveys Surveys during 1974 located 21 potential spawning and rearing sloughs on the Susitna Riv~r bevNeen Devil Canyon and the Chulitna River.Seven additional slough areas were located durinq the winter and summer of 1075 (Figure 2).Rearing fish \'/ere observed in 22 of the slough areas.:\dult salmon were present in 8 of the 21 bach/ater areas.Seven clearv/ater streams along the Susitna River were also surveyed.Adult salmon were observed spawninq in all streams and rearinn fry were observed in four. The adult salmon and rearin~fry densities are summarized in Appendix II, Table 2. Coho fry populations were the most numerous rearing fry species observed.Coho fry were observed in 19 slough areas and 3 streams (Appendix II,Tables 2-6).The majority of fry sampled for age analysis were 0.0 age fish (Table 14). Only three 1.0 age fry were collected during the season and these were located above a beaver dam in Fishwheel Slough (located at the east bank fishwheel camp)suggesting a possible migrational barrier to these individuals.Coho fry ,,,ere found in ~Jhisker's,Chase,Lane and f1cKenzie Creek (Appendix II,Table 7).All fry sampled were 0.0 age class.The mean length ranged from 49.8 to 61.3 mm (Table 15). 22 - - Tabl.9.Age,let'lgthandwetghtanalystsofcohofrycollectedintheSusttnaRtverandSloughsNUIlIbers8A,9,9A,11,'13,17,19,21,Devtl',CanyonWinterProject,1974-1975.SloughNo.Date0.0AgeClass1.0AgeClasssamplePercentLen9thStandardWeightStandardconditionBroodPercentLen9thStandardWeightStandardconditionBroodSizeComposition(mm)Deviation(9)DeviationFactorYearComposition(mm)Deviation(g)DeviationFactorYearSA99A111/17/7511/6/741/17/752/18/752/18/7511/6/741/15/752/15/7521027886250.0100.050.0100.0100.0100.085.7100.06464.36470.173.561.062.362.05.84.34.56.55.02.83.03.13.03.74.92.83.42.81.10.6O.go.gD.80.11.1441.1661.1441.0741.2341.2421.4061.175197319731973197319731973197319735050.014.37483834.85.85.81.1851.0141.014197219721972.-------------------------------------------------------------.-------------_._---.----------------------------.._--_.-...------------------.-------_._------._~-------_._---.133/12/757100.067.44.63.10.81.0131973------------------------------------------------------------------------------------------------------------....-.._------------_._-----------_._.--------------------------------------------_._---------_.----__---.--_._------_-.-----_.._--_.--_._-----.--~-.._-__...•..........----.-....•...•••.•..-_..-........•rvwSusitnaR.1/16/75IatGoldCr.2/14-16/756(S1.11o.17)3/12175·3100.0100.0100.062.070.068.04.91.02.73.92.90.90.71.1331.1370.922197319731973192/17/75100.067.03.4l.1301973__r.•••.••__._•••••••••••••••••__.~•__••__••_••_•••••_._•••••••••••••••••••••••••••••_•••••••••__••_213/12/755100.065.23.82.60.50.9381973----------------------.------_..------------------_...----...-------....._----....._-----.-.-.._----.-...-...._..............•..•....•.....••.••.•••..........••.--....------SusttnaR.atCurry3/14175100.069.03.31.0051973._------_--._-.___-- --..........•..•.....__._----.._.--..SusttnaR.,2.5mtlusouthTalkeetnaR.4/4/7512100.064.24.92.70.61.0201973 Table10.SurveyofwinterconditionsinIndianRiver,LaneCreek,andGoldCreek,Devil'sCanyonWinterProject,1974-1975.TemperatureIceIceSnowDepthWaterAnchorStreamSurveyDateTime(oF)ThicknessCoveroniceDepthIceSite(military)AirWater(inches)(%)(inches)(inches)FlowPresentIndian River3.012/6/74093021341.5-3.5504-2412-14yesno3.01/15/75115518343.0-5.01008-3612-yesno0.22/18/75093427327-1210014-407yesno0.33/11/75103027329.599.524-3512yesno----------------------------------------------------------------------------------------------------------------------------LaneCreek0.112/6/7415002835.50.5-1.0906-248-127.2111no0.11/13/7514056331.0-12.0992-365yesno0.12/18/75153828336.0-14.01005-367yesno0.13/14/75130030330.0-1.0500-367yesnoGoldCreek0.312/6/7408302132.512.0-14.09824-486-9yesno0.31/15/75100621332.0-12.010012-487yesno0.32/16/7511001532.51.0-7.010028-367.2yesno0.33/13/75114530330.0-36.0950-2415yesno11CubicfeetpersecondI\)~ lTable11.AnalysisofwaterconditionsatChaseCreek.Devil'sCanyonProject.1974-1975.Date(mllitary)A1r(OF)Water{oF)p.)12/6/74170028342.0";~6>i~,,','.:t.1/13/751145-9322'0'"jiji"57'J'::,,~,""14'2/18/75163027322.Q,~'-'&",'f3/14/75143030 322.0262~nd'-orleePresent1214.86.7>96951.0-24no'·5810.45.748750.5-12no99.05.850.10024-30no419.05.3201001-24)'esTable12.Analysisofwater~onditionsatGoldCreek.Devil'sCanyonProject.1974-1975.SampleSuspendedSolidsWaterIceSnowAnchorDateTemperatureSizeSettlableNon-filterableTotalsuspendedD.O.pHDepthCoverDepthIceAir{6F)Water{OF)(1)(mg/1)(mg/1)(mg/1)(ppm)(inches)(~)(inches)Present.12/5/753033.52.021425>6.45.648300.5-6no1/14/756322.05715810.45.748750.5-12no2/14/7514322.01912010.15.847950.0-18no3i16/7525322.022417.05.5>50950.0-12no3/29/75322.054915.05.4>50950.0-8no7/23/7568482.0329523818/4/752.018916205>608/14/755342.2.011310123>608/27(7556452.014720167>609/2/755544t.O33134>60I\)Vl Table13.Analysisofwaterconditi~nsattheAnchorage-Fairba~ksHighwayBridgecrossing.Devil'sCanyonProject.1974-1975.SampleSuspendedSolidsWaterIceSnowAnchorDateTemperatureSizeSettlableNon-filterableTotalSuspendedD.O.pHDepthCoverDepthIceAir(°F}Water(°F)(1)(mg/1)(mg/1)(mg/1)(ppm)(inches)(%)(inches)Present12/19/741632.52.022414.26.8>96759.7-131/12/75233',I2.0422422812.85.642909nojii1/22/75':,,'12.022412.17.8902/18/7523322.0102128.85.95010012no2/20/752.06179.7no3/9/7525322.041510.85.9>501001-36no3/25/752.011211.04/4/752232.52.021311.05.7>509910.3no4/2.1/7539 332.0641014.56.0>50990-12no4/24/752.032513.27.85/14/752.0842865/27/752.026462706/9/7550452.0155221776/20/752.0163131777/21/752.035874432f\)0\J,t~ Table 14.Age and length samples of coho fry collected at Sloughs Numbers 1,2,3,4,5,6,9, 10,11, 13,14,15,17,20,21 and Fishwheel Slough,Susitna River,Devil's Canyon Project,1975. Slough No. 0.0 Age Class Date Sample Percent Mean Standard Size Composition Length(mm)Deviation 1.0 Age Class Percent Mean Standard Composition Length(mm)Deviation 1 2 3 3A 38 4 8/11 8/5 9/24 7/29 7/29 8/5 8/23 8/2 8 8 8 4 4 8 9 8 100 100 100 100 100 100 100 100 53.3 58.9 60.4 57.3 55.3 55.8 60.0 49.9 6.4 2.3 2.0 5.4 4.4 3.1 6.2 5.1 6 7/26 8 100 57.9 7.0 ------------------------------------------------------------------------------------------------ 8 9/27 1 100 69.0 9 10 11 13 14 15 17 20 8/9 8/7 8/7 3/12 7/28 9/25 7/23 9/4 7/29 8/14 3/12 7/29 8/14 8 8 8 7 7 2 8 6 8 9 3 8 8 100 100 100 100 100 100 100 100 100 100 100 100 100 53.5 50.8 55.0 67.4 50.1 64.0 61.3 61.3 59.1 52.2 68.0 54.9 60.6 5.3 7.8 3.2 4.6 8.8 7.0 4.7 1.9 5.7 3.0 1.0 2.4 3.4 21 3/12 5 100 65.2 3.8 ·f~~h~h;;1---8i2~----4---------~25---------65~O-------------~------;~----~---------------------- Fishwheel 8/25 4 100 70.3 6.7'99.0 9.5 27 Table 15.Age and length samples of coho fry collected at Whisker's Creek.Chase.Lane and McKenzie Creeks.Susitna River.Devil's Canyon Project.1975. Slough No. 0.0 Age Class 1.0 Age Class Date Sample Percent Mean Standard Percent Mean Standard Size Composition Length(mm)Deviation Composition Length(mm)Deviation Whiskers Cret!k Chase Creel< Lane Creel< McKenzie Creek 7/28 7/17 7/26 8/6 8 8 8 8 100 100 100 100 49.8 50.0 61.3 51.0 4.6 5.0 5.7 3.9 Table 16.Age and length samples of king salmon fry in Slough Number 15.Susitna River. Devil's Canyon Project,1975. y' 0.0 Age Class Slough Date Sample Percent Mean Standard Mean Standard Condition Size Composition Length(mm)Deviation Weight Deviation Factor 15 8/14 6 100 50.7 3.7 1.3 0.23 1.013 28 the Sloughs - King salmon fry (~.tshawytscha)were collected in Slough Number 15. The mean length and mean weight were 50.7 mm and 1.3 gm,respectively (Table 16).~ID sockeye salmon fry were observed in the sloughs by survey crews in 1975. Resident fish species were found in sloughs containing salmon fry. Grayling fry (Thyma11us arcticus)were observed in Sloughs Numbers 2,10, 11,13,20 and 21.Whitefish fry (Coregonidae)were found in Slough Numbers 8,10,13,20 and 21.Juvenile rainbow trout (Sa1mo gairdneri) were observed in Slough Number 20.Scu1pins (Cottidae)and suckers (Catostomidae)were observed in many slough areas. Limited artificial substrate sampling was conducted to determine species composition of the insect population in tributary streams of the Susitna River.Foregut analysis of salmon fry provided comparative data on food availability.The most common insects were stonef1ies (P1ecoptera: Per10didae:Isoper1a sp.)and "no-see-ums"(Diptera:Ceratopogonidae: Dasyhe1ea sp.'.Also present were: Simu1iidae:Diptera (black-flies) Heptageniidae:Ephemeroptera (mayflies):Cinygma sp. Ironodes sp. Rhyacophi1idae:Tricoptera (caddis flies):Rhyacophi1a sp. Psychomyiidae:Tricoptera (caddis flies):Psychomy;a sp. The low number of insects captured was due to the late dates of substrate installation.No P1ecoptera were found in Haterfall Creek samples.P1ecop- tera adults were,however,very common after late July.No-see-ums adults were also very common accounting for the low number of larvae in the samples. Large numbers of Psychomia sp.larvae (up to 4 per sq ft)were observed in the silt bottoms of some areas (Sloughs Numbers 4,14 and McKenzie Creek). Substrates should be installed in early June to provide more detailed data on species composition. Foregut analysis of coho fry demonstrated the importance of insect larvae in the diets of rearing fish (Table 17).Salmon eggs were also an important food source.A larger variety of insects were present in the Tal- keetna River stomach samples.This is probably due to the time of year these fry were collected.More detailed studies on insect populations and their importance in salmon fry diets is required. / Escapement Surveys Chum salmon spawning occurred in Sloughs Numbers 3,9,13,15, 16,21,Lane Creek and Indian River.Peak spawning occurred during last week of August and first three weeks of September (Table 18). NumDers 9 and 21 contained the largest numbers of spawning adults. Spawning sockeye salmon were observed in four sloughs and three streams. Sloughs Number 3-B and 21 contained spawning sockeye and chum salmon.The highest density of spawning occurred in Sloughs Numbers 11 and 21.The peak of spawning occurred between August 26 and September 27 (Table 18). 29 Table 17.Stomach content analysis of coho salmon fry collected at Sloughs Numbers 9, 11 and 15.Susitna River and Slough Number 2.Talkeetna River.Devil's Canyon Project.1975. Length Weight Relative Slough"No.Date (mm)(9)Condition Contents Susitna River 15 8/14/75 50 1.6 full 1 egg.1 Diptera larvae 5 Trichoptera 1arvae 50 1.3 empty 50 1.4 1/2 Trichoptera larvae.detritus Diptera larvae 58 1.8 full 1-egg.detritus.Oiptera larvae 55 1.5 1/2 1 egg 54 1.4 3/4 Diptera larvae,algae.Trichoptera 1arvae.detritus 50 1.3 empty 50 1.4 empty 53 1.5 1/2 Diptera larvae &pupae,algae, Trichoptera larvae,detritus 9 9/6/74 78 6.1 full 2 -eggs 65 3.6 1/2 Oiptera nymphs 61 3.2 full 2 eggs.Diptera nymphs 60 2.6 1/2 3 Diptera larvae 69 4.2 full 2 eggs.1 Trichoptera larvae -65 3.3 empty 68 3.7 1/3 1 egg 66 3.4 empty 63 3.0 empty 54 2.3 1/4 detritus -----------------------------------~-------------------------------------------------11 9/6/75 67 4.0 full 2 eggs 63 2.9 empty 60 2.7 full 2 eggs,?Trichoptera 57 2.4 1/2 ?Trichoptera,detritus,algae 58 2.5 full 2 eggs,detritus 55 2.0 full 1 egg.8 Trichoptera (he3ds) Talkeetna River 2 6/5/75 49 1.4 3/4 8 Trichoptera larvae,blue-green algae.?Diptera larvae 49 1.5 full Diptera larvae &pupae,algae, detritus,Trichoptera,Odonata, Plecoptera.Coleoptera 56 1.8 3/4 Trichoptera larvae,algae.detritus, P1ecoptera.Diptera larvae 48 1.3 empty 47 1.3 1/2 Trichoptera larvae,detritus,algae 45 1.2 full Trichoptera larvae,Diptera larvae Odonata (?),detritus 46 1.3 3/4 1 egg.Trichoptera larvae,algae Diptera larvae 30 31 Pink and king salmon were observed spawning only in clearwater streams. The peak in pink spawning was from August 12 through August 17 and the peak of king spawning from July 29 to August 12 (Table 18).The survey counts of the clearwater tributary streams do not reflect the total number of spawning salmon,but only the density within the index areas (Appendix II, Table 7). Talkeetna and Chulitna River Investigations Investigations were initiated on the Talkeetna and Chulitna Rivers in June 1975.Surveys located 13 potential spawning and rearing sloughs and two clearwater tributary streams in the Talkeetna River from the con- fluence with the Susitna River upstream about 16 miles (26 km)to Clear Creek (Figure 3).The mainstem Talkeetna River flowed through some of the potential slough areas making fry counts impossible due to silty water conditions.Only one slough area was accessible by boat on the Chulitna River due to the braided nature of the mouth.One slough was identified on the mainstem Susitna River from the Talkeetna River downstream to the Anchorage-Fairbanks Highway bridge (Appendix I,Figure 41).No fry were observed in this slough. Rearing coho and chum salmon fry were observed in the Talkeetna River slouqhs during June surveys.Chum salmon were collected from Sloughs Numbers 1,4 anc Beaver Pond Slough.Seventeen samples were collected from Slough Number 1 (Table 19).The mean lengths of chum salmon fry from Beaver Pond Slough and Slough Number 4 were 38.4 and 37.6 mm,respectively.No chum salmon fry were observed in the sloughs after the first week of June. Coho salmon fry were observed in Sloughs Numbers 1,2,9 and Beavpr Pond Slough during June surveys.The mean lengths ranged from 42.9 mm in Slough Number 2 to 73.6 mm in Slough Number 9.All were 0.0 age fish produced from the 1973 brood year (Table 20).The largest numbers of fry were observed in Slough Number 2.High water conditions in mid-June pre- vented further boat surveys.An aerial reconnaissance was conductea to observe conditions of the river and note the presence of king salmon adults migrating to spawning areas.No adults were observed.Further sampling was postponed until conditions of the river permitted. Escapement surveys were initiated the third week of July and continued through mid-September.Rearing coho fry were observed in 8 slough areas and one clearwater tributary stream (Appendix II,Tables 8 and 9).Only one representative of the 1.0 age class coho fry was collected in a Talkeetna River slough.~b other salmon fry species were observed.Grayling and white- fish,resident species,were observed in Clear Creek slough on August 19. Chum salmon were the only adult species observed spawning in the slough areas of the Talkeetna River by the escapement survey crew.Reports from sportfishermen and other department biologists did,however,document sock- eye,pink and chum salmon spawning in clearwater tributaries.Tags were recovered from Chuni1na Creek,Clear Creek and Stephan Lake (Table 4). Aerial surveys ot sloughs upstream from Clear Creek revealed high densities of spawning chum salmon. 32 - ...' - _. Table 19.Age and length samples of chum salmon fry from Slough Number 1, Beaver Pond Slough,and Slough Number 4,Talkeetna River,Devil's Canyon Project,1975. 0.0 Age Class Slough Number 1 Beaver Pond 4 Date 6/5 6/5 6/5 ..' Sample Size 17 10 20 33 Mean Length (mm) 35.7 38.4 37.6 Standard Deviation 2.2 3.4 3.0 Table20.Ageandlengthofcohosalmonfry{romSloughsNumbers,-,2.BeaverPond.Billion.3A.5.6.7.Whiskeyand9.TalkeetnaRiver.Devi1'sCanyonProject.1975.0.0AgeClass1.0AgeClassSloughNo.DateSamplePercentMeanL.engthStandardPercentMeanLengthStandardSizeComposition(111m)DeviationComposition(nun)Deviation6/5510048.68.107/25810054.83.009/2810062.65.1026/58/519810010042.958.97.62.3ooBeaverPond6/5210044.52.12aw.j::"'Bi11ion3A8/118/5889010065.455.84.73.110o91.0---------------------~---------------------------------------------------------------------------------------------,56&7Whiskey97/257/259/98/56/7,4888810010010010010042.554.560.958.173.65.25.08.56.53.7aaooot Three sloughs (Numbers 4,8 and 9)originally identified in June were flooded by the mainstem Talkeetna River on August 5.These 3 sloughs were flowing through for the remainder of the surveys. The mouth of Slough Number 6 dried up between August 19 and September 2.Approximately 1,000 coho fry were trapped in the slough.Water levels were sufficient to support the population,but it is not known if this area will freeze completely and result in mortalities during winter months. Water conditions of the Talkeetna River were monitored monthly at the Alaska Railroad bridge (Table 21).Total suspended solid levels ranged from 4 mg/1 in March to a peak of 185 mg/1 on July 25.The settleable sus- pended solids were normally greater than 9 percent of the total dissolved solids.Water temperatures ranged from 33°F in March to 48°F in mid-August. Dissolved oxygen levels were not a limiting factor at this location,being greater than 12 ppm. The Chulitna River was surveyed weekly from July 22 to August 25.No fry or adults were observed in Slough Number 1,Chulitna River,throughout the season.June surveys noted the presence of unidentifiable adult salmon carcasses,from the 1974 season,in the clearwater stream below the beaver dam (Appendix I,Figure 40). Climatological Observations Climatological data was collected daily,at approximate1¥2000 hours, at the fishwhee1 camp from July 7 through August 26 (Table 22).The maximum air temperature during this period was 76°F and the minimum was 52°F.The maximum and minimum water temperatures were 62°F and 50°F,respectively. The Susitna River level fluctuated a maximum of 3.1 feet (0.9 m)from July 7 through August 26.The maximum twenty-four hour fluctuation in the river level was an increase of 0.9 feet (0.3 m)which occurred between July 27 and July 28.Atmospheric observations during the 51 day period indicated that 3 days had a cloud cover less than 5 percent of the sky and 13 days were completely overcast. Water temperature profiles,recorded 24 hours a day with a Ryan thermograph,demonstrate relatively low fluctuations in water temperatures at Gold Creek during winter months (Figure 11).Profiles of water and air temperatures at the fishwhee1 site suggests a significant daily warming and cooling of water temperatures (Figure 12). DISCUSSION AND SUMMARY Gross indications of migrational timing,abundance by species and age- length-sex data was obtained from f1shwhee1 operation in the lower study area.The total catch of salmon during the 1975 season was less than 1974. Chum and pink salmon dominated the fishwhee1 catches.Population estimates were determined by the Peterson mark and recapture method.The population estimates for 1974 and 1975 were: 35 Table21.AnalysisofwaterconditionsoftheTalkeetnaRiveratthe,AlaskaRailroadbridge.Devil'sCanyonProject,1975.SampleSuspendedSolidsWaterIceSnowAnchorDateTemperatureSizeSettlableNon-fl1terab1eTotalSuspendedD.O.pHDepthCoverDepthonIceAir(OF)Water(oF)(1)(mg/l)(mgl1)(mgl1)(ppm)(1nches)(%)Ice(inches)Present3/16/7530333 314185.6:>501006-12no4/3/75293333613717.95.532.59510.8no4/21/75403422312418.55.6:>606/5/755042269271>727/25/7557482168171858/19175554821718179911/755645224125--w0\, Table 22.Climatological observations at the fishwhee1 camp,Devil Canyon Project,1975. Date Air Temp Water Temp Water Guage Cloud Cover (mi 1itary)(oF)(oF)(feet)(percent) July 7 2100 67 58 2.1 10 8 2000 76 62 2.2 5 9 2000 76 62 2.3 80 10 2020 76 62 5 11 2200 65 62 2.2 90 '..,'~••;..••,<12 2000 55 58 2.6 100 13 2000 53 54 3.2 100 14 2000 65 54 3.0 60 15 2000 52 51 2.4 100 16 2000 58 54 2.6 30 17 1945 64 55 2.1 90 18 2000 59 55 1.8 40-19 2000 54 52 2.0 100 20 2000 53 51 2.3 100 21 2000 53 50 2.6 100 22 2000 57 51 2.5 5 23 2000 60 52 1.8 90 24 2000 57 53 1.5 100 25 2130 54 53 1.7 100 26 2000 55 52 1.7 ·90 27 2000 59 53 1.5 60 28 2020 58 53 2.4 60 29 2000 53 51 2.2 100 30 2000 54 53 1.7 100 31 2000 54 51 1.6 95 August 1 2130 54 51 1.6 90 2 2000 60 56 1.5 50 3 2000 58 54 1.3 100 4 2000 56 54 1.2 60 5 2000 58 56 0.8 10 6 2000 58 55 0.8 70 7 2000 58 54 1.0 95 8 2000 60 54 0.9 50 9 2000 60 54 1.0 80 10 2000 58 53 0.8 100 11 2000 59 53 0.8 60-12 2000 62 54 0.7 90 13 2000 58 56 0.5 95 14 2000 63 57 0.5 90 15 2000 55 56 0.5 100-16 2000 58 55 0.8 50 17 2000 61 53 1.3 50 18 2000 56 53 0.9 60 19 2000 57 52 0.9 20 20 2000 57 53 0.5 50 21 2000 56 53 0.3 10 22 2000 54 55 0.3 70-23 2000 57 55 0.1 10 24 2000 53 52 0.1 99 25 2000 55 53 0.1 99 26 2000 53 52 0.1 50- 37 ..3332.31.30--r-I •...I I II-,..--,--'"·--f1920212223 2425262728 293031January--~/-~.February.-u..33-0-ClI32.~:::s31-...,"'~30-ClI0.EQ)I-wOJ~33-32-31_30~,16•1I17T2I18,3I4I5I6I7T8T9r10•11I12113•141517r19, , I2123FebruaryT25-..27-r-.--------r1 3r5I7March19..----.I,1113 15Figure11.WatertemperatureprofilesrecordeddailyintheSus1tnaRiveratGoldCreek,Devil'sCanyonWinterProject,1975.t~,, 1)I80-Airtemperature-----Watertemperature7570....•cuLw::s65...\0~cu0..m...6055r--,I\'II\\\\,\,A.,../l\I',II'--''---"\/'...._/1\II\IV'__.J'\\\\..,,....J,,~50,ii..,IIIII•i,71217July2227611August162126Figure12.Profileofwaterandairtemperaturesrecordeddaily(2000hours)attheeastbankfishwheel:camp,Devil'sCanyonProject,1975. chum pink sockeye 1974 24,386 +2,602 5,252 +998 1 ,008~224 1975 11,850 +4,044 6,257 +261 1 ,835 £337 Comparative data is not available for king and coho salmon.Tag recoveries from chum,pink,sockeye and coho salmon be10vl the fishwhee1 sites indicate a significant,but unknown,proportion of the salmon captured were possibly milling and not migrating to spawning grounds above the tagging project. Twenty-one sloughs were identified and surveyed on the Susitna River during 1974.An additional 7 sloughs were identified during winter and summer 1975.Rearing fry were observed in 22 of the slough areas.Adult sa'imon were found spawning in 8 of the sloughs.Adult sockeye salmon were observed in 4 sloughs and adult chum salmon were observed in 6 slough areas. Pink,king and coho salmon adults were found exclusively in clearwater tributaries.Chum salmon were observed spawning in Lane Creek and Indian River and sockeye spawned in Fourth of July Creek,McKenzie Creek and Indian River,clearwater tributaries of the Susitna River. A minimum of 575 pink,568 chum,242 sockeye and 62 king salmon spawned in the streams and sloughs of the Susitna River between the confluence of the Chulitna River and Portage Creek as determined from peak slough and stream index escapement counts. Thirteen sloughs and 2 clearwater streams were identified and sur- veyed on the Talkeetna River between its confluence with the Susitna River and Clear Creek in 1975.Coho fry were rearing in 8 sloughs and one clear- water stream.Rearing chum salmon fry were observed in 3 sloughs in June. Chum salmon were the only salmon species observed spawning in the slough areas of the Talkeetna River.Pink salmon were,however,observed in Clear Creek by the escapement survey crew.The presence of spawning sockeye,coho and pink salmon was confirmed by sportfishermen's tag returns in Chuni1na Creek,Clear Creek and Stephan Lake. Winter surveys of the slough and mainstem Susitna River established the presence of rearing coho fry (~kisutch)in both areas.Suspended solid levels of the mainstem river were extremely low during fall and winter months resulting in clear water conditions.The combination of partial slough dewatering and clear water conditions were contributing factors of fry emigration into the mainstem river for rearing. Artificial substrate sampling and fry foregut analysis was conducted to determine species composition of invertebrates within the study area and the importance of benthic invertebrates as food items to rearing fry. Insects comprised 100 percent of the benthic organisms found in the sub- strate samples.The number of species of benthic organisms identified was extremely low.The contributing factors are the time of year they were installed and the length of time they remained in the sampling loca- tions.The Plecoptera (stonef1ies)and Diptera (llno-see-ums")represented the dominant orders.Simuliidae (black flies),Ephemeroptera (mayflies) 40 - - and Tricoptera (caddis flies)were also present. Various environmental changes will occur as a result of dam construc- tion on the Susitna River.The most obvious change produced will be the flooding of about 82 miles (132 km)of river above the Devil Canyon Dam- site.Anadromous fishes are not found in this section of the river.En- vironmental changes will,however,occur downstream as a result of river impoundment.The effects will occur not only on the mainstem Susitna River but also on the Talkeetna and Chulitna Rivers. Deposition of the Susitna,Talkeetna and Chulitna Rivers will be altered by dam construction.The Chulitna River carries a large bed load and suspended load to its confluence with the Susitna River.The braided nature of the Chulitna at its mouth and the extension of this condition several miles up the Susitna,indicate that this portion of the two rivers has a sediment transporting regime that could readily become depositional. The loss of peak flows in the Susitna River will favor deposition and related f100dinq in the flats of the Chulitna River above its confluence (Bishop,1974). The Talkeetna River does not carry the sediment load of the Chulitna River,but it may also be affected by regulation of the Susitna.The effect would most likely be in response to the Chulitna's deposition of sediments acting to backwater the Talkeetna River.Flooding conditions in the Talkeetna River would most likely be enhanced (Bishop,1974). Temperature regimes and velocities in the Talkeetna and Chulitna Rivers are also expected to be altered.Potential changes such as these warrant continued studies of the fish populations in these tributaries. Descriptions of potential impacts and suggestions for further studies have been compiled by Department of Fish and Game,Sport and Commercial Fisheries biologists.These '."ere compiled jointly,since many areas over- lap and would result in unnecessary repetition.These are included in the next section of the report. There are no present methods of affixing a value on the Susitna River salmon production.Total escapement data by species by year is not available for the Susitna River drainage due to the glacial water conditions of this system which prohibits visual observation and total escapement counts.Test fishing and fishwhee1 tag-recovery programs have been and are still being conducted in the lower Susitna River and its tributaries (Yentna and Ta1a- chulitna Rivers and Susitna River at Susitna Station),but have been unsuc- cessful in providing total escapement figures to date.The utilization of sonar to provide escapement data for the Susitna River has not been explored fully.An experimental program may be initiated by Department of Fish and Game in 1976.We can only estimate the monetary values of the Susitna River salmon stocks at this time.Department of Fish and Game Commercial Fisheries biologists have derived a method of determining the monetary values,but it must be emphasized that these figures are at best "guesstimates"(Appendix IV)• 41 POTENTIAL mp/-\CTS AND RECOW1ENDATIONS Impoundment of the Susitna River,from Devil Canyon upstream 84 miles, by the Devil Canyon and Watana Dams will inundate some 50,500 acres of land.Environmental impacts \'li11 occur both up and downstream from the dams.Two phases of deve10p~ent of the hydroelectric facilities will occur: (1)the construction period projected to extend over a 12-year period and (2)the operation of the facilities which \'1i11 provide hydroelectric power to the Southcentra1 Rai1be1t area.Environmental impacts of this project can be divided into two phases:(1)those occurring during the construction period and;(2)those occurring during the post-construction period which will encompass the entire life of the project. Construction Period Impacts Construction of the dams will necessitate the diversion of the Susitna River from its natural course.The major effect during this period is expected to be an increase in silt load due to construction activities. This decrease in water quality ~ay cause the following impacts: 1.Disorientation of adult salmon returning to their home streams, resulting in a decrease or lack of production in the upper areas of the river. 2.Change in substrate composition in sloughs resulting in decreased spawning area.Chum (Oncorhxnchus keta)and sockeye salmon (Q.nerka)are known to utillze these areas for spawning. 3.Lack of clearwater conditions during fall and winter months pre- venting fry from utilizing the mainstem Susitna River for rearing. 4.Degradation of water quality resulting in possible alterations in the aquatic food chain.Some orders of insects,important food items for salmon fry,may be unable to adapt to the changed water quality and the entire food chain will be altered. 5.Reduction of flow during construction years and initial filling of dam would remove much spawning habitat and could eventually change fish distribution below dam.During the low flow con- struction period a substantial risk of water pollution from con- crete pouring,oil spillage,etc.,could occur. 6.Reduction in run of salmon would follow reduction of flow (Penn, 1975).Reducing flows could result in access restrictions to salmon utilizing the upper regions. 42 .. - - Post-Construction Impacts 1.Turbidity The Susitna River currently carries a heavy load of glacial silt in spring and summer.The rivers water is clear during fall and winter months.Impoundment will result in a milky color of the water year-round.Turbidity may also be increased if there is permafrost in the area (Afton,1975).This condition may result in: a.Inability of fry to utilize the mainstem for rearing. b.Erosion of gills of adults and fry due to the silty condition of the mainstem Susitna River. c.Increased light penetration due to decreased summer turbidity would encourage more primary production.Rate of zooplankton development may not necessarily be increased due to possible lower temperature in the April-May period.Rearing salmon depend on zooplankton stock at this time. d.Influence of bedrock on impoundment water quality may affect fisheries.(Duthie and Ostrofsky,1975). - - e.Increased mortality due to decreased summer turbidity and increased predation success might occur (Geen,1975). f.Decreased spring and summer turbidity would likely limit downstream migration to the darker hours,thereby extending the downstream migration periods even further than at present since some migration occurs in the turbid water during day- light.There is evidence suggesting that increased time to migrate would increase young salmon mortality (Geen,1975). 2.Tempera tu re Normal temperature regimes will be altered by impoundment.Various effects may be seen. a.Any increases in downstream fall temperatures could affect spawning success of salmon.There is evidence that relatively high temperatures are associated with poor returning runs (Geen,1975). b.Increases in temperatures could result in change in the incuba- tion period of salmon eggs and incubation conditions. c.Increases in temperature could result in premature fry emergence and seaward migration due to increased rate of development.In- creased mortality could occur because the migration may occur prior to development of estuarine and marine zooplankton. 43 ------------..,.._.~~..,_._-------- d.Alteration of the normal thermal regime would change the over- all productivity of the river,which could add extreme stress to fry populations. e.A decrease in summer temperature could effect upstream migra- tional time for adult salmon,but its critical nature is un- known. f.Changes in the aquatic food chain would be expected due to the inability of some organisms to adapt to even slight thermal alterations.The elimination of even one invertebrate species could affect the remainder of the food chain. 3.Chemical and Physical Parameters a.Reservoir supersaturation of both dissolved oxygen and nitrogen resulting from stratification and spillage can be expected, impacting downstream fishes for an unknown distance (Geen,1975). b.Increases in dissolved nitrogen gas could also result from air vented into turbines to reduce negative pressures during week- end periods of sustained low generating levels (Ruggles and Watt,1975). c.Dams slow down water transport which gives more time for the biochemical oxygen demand to consume available oxygen,thus reducing dissolved oxygen content. d.Conductivity,alkalinity,and pH can increase after impoundment construction (Geen,1975). e.Dissolved oxygen levels will probably be altered due to changes in river conditions.Levels below 5 ppm would preclude the survival of fish in slough areas. 4.Organic Debris a.Debris has a time frame of 100-200 years.This time frame would be reduced with time as a result of forest drowning. b.Population explosions of fish,benthos,and plankton may result from the addition of organic nutrients. 5.Water Flow a.Altered lake levels may result in flooding,slumping,erosion and general shoreline degradation.Littoral zone changes af- fect fisheries. b.Changed ice regimes can also affect river and lake shorelines. A change in water quality can be expected due to erosion and sediment processes from altered water levels,flows and ice regimes (Dickson,1975). 44 .... - - c.Changes in substrate composition of spawning areas due to lack of natural scouring could affect winter survival of eggs. d.Decreases in water levels during June and July could affect adult access to spawning areas. e.Reduced discharge during summer could delay the migration of adult salmon upstream. f.Reduction of discharge could affect survival of young salmonids moving to saline water during April-t1ay.Seaward migration is directly related to river velocity and therefore could extend this period (Geen,1975). g.Reduction of normal spring and summer flows could result in a decrease of fry rearing habitat. Recommendations Before the full effects of this project are identified as related to fish and wildlife,considerable studies are necessary which are goinq to be both lengthy in time and costly in money.A brief resume of biological studies and investigational goals required prior to final definition of fish losses and/or gains resulting from impoundment of the Susitna River at Devil Canyon and Watana are: I II III A thorouTh literature review of hydroelectric facilities is needed. This wou d provide information on pre and post-construction studies and indicate areas of potential concern. A thorough hydrologic study is essential.This study may have to be conducted in close coordination with a private engineering firm. The following is a partial list of necessary information. 1.Current unregulated flows and projected regulated flows. 2.Temperature regimes. 3.Turbidity and sediment data. 4.Anticipated physical changes to the natural stream course as a result of flow alterations. A comprehensive fishery study to address adult and juvenile salmonid abundance,distribution,migrational patterns,and age composition by species for areas both upstream and downstream of the proposed Devil Canyon Dam. The Cook Inlet fishery is of mixed stock and presents many problems for its proper management.Total escapement data by species is not available for the Susitna River drainage.Until we are able to de- termine total escapement into the drainage we will not be able to 45 determine the value of the salmon stocks in the upper Susitna River. Spawning ground surveys do,however,demonstrate the importance of this area to chum and pink salmon. Data collected since July 1974 provides us with baseline information only.Generalizations may be made,but sufficient information is not available to determine exact impacts of dam construction and operation upon the fishery.Intense investigational projects should be initiated in the study area to provide pre-construction data to adequately evaluate possible impacts. IV A study of affected habitat areas will be conducted in conjunction with the fisheries program.Productivity and limiting factors can be defined by a thorough limnological study.Physical,chemical and biological conditions of the Susitna River and its tributaries should be examined.A few specific concerns are: 1.Changes in quality and quantity of spawninq habitat both upstream and downstream of the proposed dam sites as a result of a)flow and releases,b)innundation of upstream areas and c)effects of periodic pool fill and drawdown. 2.Effects upon the habitat and fisheries resource directly as a result of construction activities. 3.Effects of increased human use resulting from improved air and road access upon both the Susitna ~iver drainage and adjacent fisheries. These studies can be conducted in conjunction with the fisheries studies. Before ADF&G can completely outline the objectives of hydrological biologi- cal and environmental studies,the Corps of Engineers will also need to supply the following data: 1.Finalized plans on locations,desiqn criteria,and features of dams. 2.Year-around data on current projections of regulated flows.The flow regimes are of utmost importance in determining what is re- quired to protect fishery values. 3.Frequency and timing regarding spilling of excess water.Seasonal time and amount of reservoir drawdown is also required. 4.Description of access routes and distances and their status,i.e., private or public. A means for advising this department of design or operational changes which may necessitate alterations in investigational programs is critical. 46 - - - - -., ..... - .- - -' - Project Time Span &Costs Estimates from private engineer consultants indicate adequate and com- prehensive hydrologic studies will require a minimum of one year to complete, but ideally should continue for a three year period. Including the required personal services,equipment,and operational costs,etc.,a total figure of $4-500,000 will be required annually. The fisheries investigations required for both the upstream (above Devil Canyon)and the downstream area will require four to five years to complete due to the life cycles of the salmon species involved and the length of time required to assess habitat and environmental changes. Costs for all fisheries studies,including resident and anadromous, for areas both upstream and downstream of Devil Canyon Dam are estimated at $300-350,000 annually.These figures include necessary personal services, operational costs,equipment,materials,etc.Included in this sum are monies for fulltime professional biologists to act as project leaders and direct the investigational programs.It can be anticipated that as the above mentioned projects are conducted the estimated budget figures stated may require modification . 47 __......-1","",uoiIIIi'r.,.·lilIIR.·W_.·'..5 .........'$=.........t....··~'~·.>,:...,·~""'-·.."_"·_,1__"'_'....•_.~._ ACKNOWLEDGEMENTS Funding for this study was provided by U.S.Fish and Wildlife Service and National Marine Fisheries Service. The author wishes to acknowledge the technical assistance provided by the follolr/ing Department of Fish and Game employees: Randy Brandon r1ark Foll ansbee John Gallop Craig Hollingsworth Ward Knous,Project Leader r'1i ke Stratton Special credit is due Craig Hollingsworth for his identification of invertebrate samples and Ward Knous for his performance in the field as proj ect 1eader. 48 - - - - ... - REFERE;~CES Anonymous,19~1.Progr~ss report,1956 field invest~ations Dev~l Ca~~~ Damsite,Susitna River Basin.U.S.Fish and Wildlife Service,Juneau A1as ka .15 I). APHA,AWWA,and WPCF,1971.Standard methods for the examination of water a·nd waste\vater.13th edition.American Public Health Association,- Washington D.C.pp 539-540. Barrett,B.M.,1974.An assessment study of the anadromous fish populations in the up~er Susitna River watershed between Devil Canyon and the Chulitna River.Alaska Department of Fish and Game,Division of Commercial Fisheries (unpublished).56 p. Barrett,B.M.,1975a.December investigations on the~per Susitna River watershed between Devil Canyon and Chulitna River.Alaska Department Fish and Game,Commercial Fisheries (unpublished).B p. Barrett,B.M.,1975b.January investigations in the~er Susitna Rt.Y..er watershed between Devil Canyon and Chul ana Rt~e...r..Alaska Department Fish and Game,Commercial Fisheries (unpublished).10 p. Barrett,B.M.,1975c.February investigations in the upper Susitna River watershed between Devil Can~and_Chul i t~~Ri ver.Alaska Department Fish and Game,Commercial Fisheric.:(unpublished).10 p. Beeton,A.M.,1961.Environmental changes in Lake Erie:Am.Fisheries Society,90,(2):153-159. Bishop,D.M.,1974.A hydrologic reconnaissance of the Susitna River below Devil Canyon.UnpUblished report submitted to National !"1adne Fisheries Service of NOAA,Juneau,Alaska.55 p. Efford,I.E.,et.al.,1975.Environmental impact assessment and hydro- electric projects:hindsight and foresight in Canada ..Journal Fisheries Research Board of Canada,32,(1):97-20~. Hinckin,N.E.,1968.Caddis larvae.Cranbury,N.H.,Associated Univ. Press,Inc.,480 p. Pennak,R.W.,1953.Fresh-water invertebrates of the United States:New York,The Ronald Press Co.,769 p. Reid,G.K.,1964.Ecology of inland waters and estuaries:New York, Publishers,Corp.,375 p. Ward,H.G.,and G.C.Whipple,1959.Fresh-water biology:John Riley and Sons,Inc.,New York.1248 p. 49 APPENDIX I The slough areas of the Susitna,Talkeetna,and Chulitna Rivers have been referred to throughout the text.A diagranmatic sketch of each slough and some clearwater streams follows.The drawings are not to scale and are intended to define the slough area,its relative size,substrate composition, and sampling sites. 50 - ... - - beaver dam-- - - Appendix Figure 1.Map of Slough Number 1,Susitna River,as comoosed on September 3,Devi1's Canyon )roject,1975." 51 ud bottom 1/3 mi. Ap!lendi x Fi gure 2.Map of Slougll rlumber 2,Sus i tna Ri ver,as composed on Septe~ber 3,Devil's Canyon Project,1975. 52 - - - 2 11 -iC"cobble bott om .....". bottom f Appendi~Figure 3.~aD of Whiskers Creek,Susitna River,as composed on'September 3,Devil's Canyon Project,1975. 53 - 3A ... - \~38 -'\\ '\.~ !~~'\~..,\'\~~~,- N ~~~,I \\\- \\,\II 1/4 mi 1 I.... I - IIppendix Figure 4.Map of Slough Humber 3-11 and Number 3-B.Susitna River,as COffinosed on Seotember 4,Oevil's CanyonProject,1975.54 - - .- .Appendix Figure 5. 450 yds Map of Slough Number 4,Susitna River,as composed on September 4,Devil's Canyon Project,1975. 55 1/2 mi N 3"-a"cobble batt am .Appendix Figure 6.Map of Chase Creek,Susitna River,as composed on Seotember 4,Devi1 1 s Canyon Project,1975. 56 - - Alaska Railroad It 1,150 ft. I and boulders 90%cobbles 10%sandy silt 1/~mi le - .- Appendix Figure 7.Map of Slough Number 5.Susitna River.as composed on ·August 16.Oevil's Canyon Project.1974. 57 I ~~1ile Post , 237.0 \ 900 yds. Ri ffl es ~ i "- J ClJ -.~ ci: 90%pebbles~cobbles ~- and boulders t) c:::10%sandy silt ""-l..... CI) ~ ...N , ~Alaska Rail road Appendix Figure 8.Map of Slough Number 6,Susitna River,as composed on August 16,Devil 's Canyon Project,1974. 58 - - 1rees 400 yds. r 1rmud covered gravel',i bottom J 1 "'--30yds. dams trees Appendix Figure 9.Map of Slough Number 6-A,Susitna River,as com~osed on September 5,Devil's Canyon Project,1975. 59 ... - t11le Post 241 Alaska Railroad pebbles Boulder ....~ ! ""Cb ~...... Q: \ ... b ~.......... II)c;Soul ders ~-" Appendix Figure 10.Map of Slough Number 7,SusitnaRiver.as composed on August 16,Devil·s Canyon Project,1974.-60 75yds 1200 yds ,"-Q) .~ I ~907.sandy silt._- 107.gravel \ and pebbles ~~..... ~ CI) ~r.-~ lit!~II Alaska Railroad~ Appendix Figure 11.Map of Slough Number 8,Susitna River,as composed on August 28.Devil 's Canyon Project.1974. 61 bottom Appendix Figure 12.Mao of McKenzie Creek,Susitna River,as composed on September 26,Devi1's Canyon Project,1975. 62 - 0- - - - - - - .. ~ppendix Figure 13.Map of Slough Number 8B,8C,and 3D,Susitna River,as com~osed on Seotember 8,Devil's Canyon Project,lQ75. 63 A~pendix Figure 14.Map of Slough ~lumber "A",'Susitna River,as composed on Septmeber 26,uevi1's Canyon Project,1975. 64 - - - 0.7 Miles Riffle ~r---1--Riffle Appendix Figure 15.Map of Slough,Number 8A,Susitna River,as composed on December 6,Devil's Canyon Winter Project,1974. 65 - - Appendix Figure 16.Map of Slough Number 9,Susitna River,as composed on August 16,Devil 's Canyon Project,1974. 66 Slough No.10 .!I ~~ Appendix Figure 17.Map of Slough Number 9A.Susitna River.as composed on February 17,Devil IS Canyon Winter Project,1975. 67 ,.- '""\....". 500yds. Appendix Figure 18.Map of Slough Number 10,Susitna River,as composed on September 8,Qevil 's Canyon Project,1975. 68 - - - - 90%sandy silt 10%cobble ~~,#--_-;--Beaver ........,,(, Dams Beaver Lodge Appendix Figure 19.Map of Sloughs Numbers 11,12,and 13,Susitna River as composed on August 9.Devil Canyon Project.1974. 69 Appendix Figure 20.Map of Slough Number 14,Susitna River,as composed on August 30,Devi1·s Canyon Project,1974. 70 - \~ -....~ "~'\",~\~ \} ~~Stream )J tll OSurveyq~Station Mile 264.1 ~t tHtttr;;:===::;:~H-Hi+~~~~~~as i11'1 Il'\ Bridge ~~ .~,\ 857.sandy silt 107.gravel 57.boulders Cle~--J _e<=~ 14ater Stream .. 800 ds. Appendix Figure 21.Map of Slough Number 15,Susitna River,as composed on August 5,Devil's Canyon Project,1974. 71 boulders - major chum salmon .lh~~t-(~1~spawning area 50'1 sandy silt so'%.cobbles and T 150 ds. Appendix Figure 22.Map of Slough Number 16,Susitna River,as composed on . August 3,Devil's Canyon Project,1974. 72 - Beaver Dam 95%sandy silt 57.cobbles and boulders 200yds. 5ft. Appendix Figure 23.Map of Slough Number 17,Susitna River,as composed on August 3,Devil's Canyon Project,1974. 73 mud bottom - - - N .•...'U IlT •..__ ••.tT ••.••~l _)Jr.._. trees.•IJI OIL. 1((((I...• I~_..\ff...Iff.VI \~..~{I-\".. "~~.vr..... trees marsh --+=. Appendix Figure 24.Map of Slough Number 18,Susitna River as composed on September 8,Devi1's Canyon Project,1975. - 74 - - r-1ajor Spawning Area 907.sandy silt 10%cobbles -- Appendix Figure 25.Map of Slough Number 19,Susitna River,as composed on August 21,Devil's Canyon Project,1974. 75 ------------------------------ - cobbles 90'%pebbles and lOX sandy silt 150 yds. N---{::;.(10 ft. Appendix Figure 26.Map of Slough Number 20,Susitna River,as composed on August 16,Devi1's Canyon Project,1974. 76 - - Sockeye and Chum Salmon Spa\·ming Pools 75%boulders.cobhl£, and pebbles Appendix Figure 27.Map of Slough Number 21,Susitna River,as composed on September 24.Devil's Canyon Project,1974. 77 ,-I I ~- - - Appendix Figure 28.Map of Billion Slough,Susitna River,as composed on Jun~9,Devil's Canyon Project,1975. 78 -' Appendix Figure 29.Map of Railroad Slough,Talkeetna River,as composed June 9 t Devil's Canyon Project,1975. 79 I ,~ /.spring 1/2 mile~~,I~'jCb ~::s ~~ ~'1l~ ~..I ~1.~~ J\ ,\....-' ~~ 60'... Appendix Figure 30.Map of Slough Number 1,Talkeetna River as composed on June 9.1975. -80 - - N Appendix Figure 31.Map of Slough Number 4,Talkeetna Riv~r,as composed on June 9,Devil 's Canyon Project,1975. 81 r I ~ "~~~~-, I~ .~~beaver IOd9~~~\ IQ) water Cb~~JS"~~~III r .....-..~~,"""~l f7 ~,-~~~f~~~. ,/3''''lOa',~S""' 2"d~"'"~.~?'"gravel d~'\JI boft()m~\1 ~~ ~~'i.: II~'l ~S I~- J ~I ,r ~- Appendix Figure 32.Map of Beaver Pond Slough,Talkeetna River,as composed on June 9,Devil's Canyon Project,1975. 82 - ----,.,~cJeor water Log Old channel-_-lil-_ - Appendix Figure 33.Map of Slough Number 3,Talkeetna River,as composed On June 9,Devil's Canyon Project,1975 . - .' 83 I 1/2 mi .' - ~' ~~! .~Q.)lct~..' §I~-S II Q3')Q.)'(ri ~~l~~- Appendix Figure 34.Map of Slough Number 2.Talkeetna River.as composed On June 9,Devi1·s Canyon Project.1975. 84 .... - -- - - 200yds. Appendix Figure 35.Map of Slough Numb~r 5,Talkeetna River,as composed on June 9,Devil IS Canyon Project,1975. 85 - ... - 4~ Li 20 ,i ~~I ,1 'i!t 1/ (,~i no.6 bottom: f mud with cobble to 611 ) I.J (.~ spring area 112 mile clear water. riffl e ~ X Xl~1.'7.\1~I.old beaver dam Ji ~~\l5.--::---...--=-~-=-----~-~___Talkeetna River no.? ~ Appendix Figure 36.Map of Sloughs Numbers 6 and 7,Talkeetna River,as composed on June 9,Devil 's Canyon Project,1975. 86 - - 400 yds _~~-cJear water stream bottom mud bottom Appendix Figure 37.Map of Whiskey Slough,Talkeetna River,as composed on June 9,Devil's Canyon Project,1975. 87 N 1 1/4 mi. Appendix Figure 38.Map of Slough Number 8,Talkeetna River,as composed on June 9,Devil IS Canyon Project,1975. 88 .... _. ... - - - - - '- Appendix Figure 39.Map of Slough Number 9,Talkeetna River,as composed on June 9,Devil 's Canyon Project,1975. 89 ·cobin "• 1/4"_2" gravel bo1tom --+41--- mud bottom log iom/ tree covered island Appendix Figure 40.Map of Clear Creek Slough,Talkeetna River,as composed on June"9,Devil 's Canyon Project,1975. 90 -Cobin Creek 2 miles Appendix Figure 41.Map of Slough Number 1,.Chulitna River,as com!Josed June 9,Devil Canyon Project,1975. 91 dams '- ~300 yds.~-l'~, - Appendix Figure 42.Map of Slough No.1,Susitna River below the Talkeetna River confluence,as composed on June 6,Devi1's Canyon Project,1975. 92 APPENDIX II Escapement surveys of sloughs and tributary streams of the Susitna and Talkeetna Rivers are presented in this Appendix.Included are counts of live tagged and untagged adult salmon in the Susitna River. 93 Appendix Table 1.Number of live tagged and untagged salmon by species observed during adult escapement'surveys,Susitna River,Devi1·s Canyon Project,1975. Chum Salmon Surve s ocation Date Survey Number Fish Sam led Conditions Untagged Tagged r Ratio c/r - Slough 38 8/27 good 9/3 good 1 50 1 o 2 50 2.0 0.0 Lane Creek 8/17 excellent 8/27 excellent 3 1 oo 3 1 0.0 0.0 Slough 9 8/17 excell ent 15 0 15 0.0 8/25 good 64 0 64 0.0 9/8 good 63 0 63 0.0 9/27 excell ent 54 0 54 0.0 ---------------------------------------------------------------------------- Slough 13 9/25 good 1 0 1 0.0 Slough 15 9/6 good 1 o 1 0.0 Slough 16 8/26 good 12 0 12 0.0 ---------------------------------------------------------------------------- Indian 8/8 good 0 2 2 1.0 River 8/9 good 0 1 1 1.0 8/12 excel.lent 70 0 10 0.0 9/26 fair 1 0 1 0.0 Slough 21 9/6 good 246 4 250 52.5 9/25 excellent 92 0 92 0.0 ---------------------------------------------------------------------------- Total 614 8 682 85.3 Pink Salmon Surveys Location Date Survey Number Fish SamDled Ratio (c/r ) Conditions Untagged Tagged \r 4th July 7/28 excellent 40 0 40 0.0 Creek 8/9 excellent 85 2 87 43.5 8/13 excell ent 50 3 53 17.7 8/17 excellent 143 5 148 29.6 8/25 excellent 95 6 101 16.8 9/8 poor Indian 8/7 0 1 1 1.0 River 8/9 0 4 4 1.0 8/12 312 9 321 35.7 --------------------------------------------------------------------------- "lane 7/26 excellent 20 0 20 0.0 Creek 8/6 excellent 78 3 81 27.0 8/17 excellent 96 10 106 10.6 8/27 excellent 22 3 25 8.3 9/3 excell ent 2 0 2 0.0 - Total 943 94 46 989 21.5 Appendix Table 1.Number of live tagged and untagged salmon by species observed during adult escapement surveys,Susitna River,Devil's Canyon Project,1975. Location Date Ratio c/r Slough 38 8/23 excellent 9/3 good 4th July 8/17 excellent 12 14 1 1 1 o 13 15 1 13.0 15.0 0.0 --------------------------------------------------------------------------- Slough 11 8/25 exce11ent 24 1 25 25.0 9/4 good 78 6 84 14.0 9/25 good 72 5 77 15.4 --------------------------------------------------------------------------- Slough 19 8/10 fair 0 1 1 1.0 8/26 excellent 18 2 20 10.0 9/6 good 10 2 12 6.0 9/24 good 10 0 10 0.0 Slough 21 9/6 good 9/25 excellent 34 48 2 1 36 .49 18.0 ...49.0 ---------------------------------------------------------~-~.---~~---~~---McKenzie 9/8 good Creek 9/27 excellent 3 45 o o 3 45 0.0 0.0 Indian River 9/26 fair 1 o 1 0.0 --------------------------------------------------------------------------- Total 370 22 392 17.8 Kin Location Date Survey Ratio c/r Conditions Whiskers 7/23 poor 2 1 3 3.0 Creek 7/28 poor 1 0 1 0.0 8/4 poor 19 3 22 7.3 8/14 3 0 3 0.0 4th July Creek 8/9 excellent 1 o 1 0.0 Indian River 8/12 excellent 10 o 10 0.0 Portage Creek Total 7/23 7/29 8/10 excellent excellent excellent 2 29 3 70 95 o o o 4 2 29 3 74 0.0 0.0 0.0 18.5 ,.AppendixTable2.EscapementsurveycountsconductedontheSusitnaRiverinSloughsNumbers1,2,3A,4,Devil'sCanyonProject.1975.FrySpeciesIdentified.c0>IIIAdultSalmonDensityTemperatureI:........4-SloughNo.DateTime(oF)SurveyNo.Fryr-(l)ChumSockeye0>0E>,+>(military)AirWaterConditionsObservedI:.s:::::s'"....LiveDeadTotalLiveDeadTotal....0.c~.s:::~uul!)::0:7/22132054 58poor00 0 0 0007/27.14206155poor00000 0 08/418106654poor00000008/1115105951good200X0 00 0 008/2215555848good200X00 0 0 009/310305448good00 0 0 0 009/2311105445good2X0000 00------~----------------------------------------------------------------._.--------------------_..._------._.-------------------27/2214405950poor000 0 0 007/2812055745poor00 0 00008/417406748excellent000 00 0 08/1115456155excellent00 00 0008/2512355745excellent0000 0 0 09/2312005445excellent100X X00 00 0 01.0----------------------------------------------------------------------------...------------------------------------------------O'l3A7/1512455244excellent00 000 0 03B13105144poor00 0 00 0 0A7/2316406647excellent00000 00B16106449excellent00 00000A7/2814105845excellent40X00 0 0 0 0B14355750excellent200X0 000 0 0A8/414356553excellent40X0 000 0 0B15106853excellent200X00 0 0 0 0A8/1412206553excellent30X00 00 00B12456844excellent150X0 0000 0A8/2314006249excellent150X000 1 011314205845excellent50X0 0 012012B8/271315----excellent.02020 00A9/212105545poor000 00 0 0B11305245good05005015015-------------------------------------------------------------------------------------------------------------------------------47/2513555956poor00000 008/212405957poor50X0 000 008/912556055poor00 0 0 0 0 08/2114005855poor00 00 0 0 01 AppendixTable3.EscapementsurveycountsconductedontheSusitnaRiverinSloughsNumbers5.6. 7.8.BA.88.Devil'sCanyonProject.1975.FrySpeciesIdentified.s=TemperatureC'IIIIAdultSalmonDensitlE:-..........SloughNo.DateTime(OF)SurveyNo.Fry.....CIlChumSockeyeC'I0e~.....(military)AirWaterConditionsObservedc.c::s...LiveDead·TotalLiveDeadTotal....0.s='-.s=:w:u uCJ:z57/2112007056pooraa a a a a a7/2614055854fair200Xaaaa a a8/610455654goodaaaa aa08/21121556 55fairl/aaaaa0a9/31230----poor-a0a a a00-------------------------------------------------------------------------------------------------------------------------------67/2112207056fair+Xa a a a007/26140558 53fair200Xaa0 0a a8/611005656goodaaa a a a a8/21123056 57fairaa aa aaa9/3.-------pooraaaa a a a\.09/271445--47goodaa aaaa a.....,_.~----._--_.------------------------------------------------------------------------------------------------------------------77/21.----------------7/2614505948excellent0a a a aa a8/612205653excepentaa aa0a a8/21------ --poorJ9/3------ --poorll---------------------------------------------------------.---------------------...--------------------------------------------.87/2113157050pooraa a a aao.7/2615305649excellent500X0aaaa a8/612305547excellent400Xaaa a a a8/1717455954excellent350Xaaaa a a8/2713156047good500Xaaa0aa9/317505545excellent1000Xa0aaaa9/2714005548excellent60XXa aaa a0-------------------.-----------------------------------------------------------------------------------------------------------SA7/2618005948excellent2aaa aa a8/915005954goodaa a a a aa------------------------------------------------T------------------------------------------------------------------------------8B8/616005548excellent300Xaaa aaa9/813105144goodaaaaa aaJJSloughareadriedup. AppendixTable4.EscapementsurveycountsconductedontheSusitnaRiverinSloughsNumbersA,9,9A,10,11,12,Devi1'sCanyonProject,1975.FrySpeciesIdentified::e0)IIITemperaturel::'r-AdultSalmonDensity'r-....SloughNo.DateTime(oF)SurveyNo.Fryr-Q)ChumSockeye0)0E>,....(military)AirWaterConditionsObservedl::.r:::.::::J",~LiveDeadTotalLiveDeadTotal'r-0.r:::.l...~U Ul..:)3:A7/2115206545excellent000 0 0008/617006451excellent00000008/1714306050excellent0000 000-------------------------------------------------------------------------------------------------------------------------------97/2115456550poor00 000 0 07/2619306048fair200X00 00 0 08/913005649excellent400X00 0 00 08/1714006552excellent0150150 008/2516005651good0642660009/812004849good06314770009/2711005045excellent054127181000~···----------------·-------------------------------Tl---....---------------------------.---------------------------------------co9A8/7------ --poo~---- - - ----------._----------------------------------------------------------------------------------------------------------------------107/2814005546poor00000 008/710506343excellent1500XX X0 0000 08/2513005744excellent600X00 00 009/419155041good1000X0 0 0 0009/2517055943good10X00 0 000_.------._------------------------------------------------------------------------------------.--------------------------------117/2210007544good0000 00 07/2813255544excellent30X000 0008/710206047excellent4000XX00 00 0 08/1317105947excellent4500X0 0 00 0 08/2512005444excellent3000X0 0 0250259/418005044good300X0 0 0840849/2516405145good00 0 077582____________________________•___________________________________________________________________________________________e____._127/2813005342good000000 08/709405743excellent00 0 000 08/1316505843excellent00 0 0 0008/2511455247good00 00 0009/417405745good00000 0 09/2516205545good3000 0 00 011Sloughareadriedup.,l,,, •••AppendixEscapementsurveycountsconductedontheSusitnaRiverinSloughsNumbers13.14.15,16.17.Devi1'sCanyonProject,Table5.1975.FrySpeciesIdentified~TemperatureenIIIAdultSalmonDensityc....SloughNo.DateTime(oF)SurveyNo.Fry.........ChumSockeye....C1I(military)AirWaterConditionsObserveden0e>.~liveDeadTotalLiveDeadTotalc..c:Jn:l....0..cL..c~uuCJ3137/2317506250poor00 00 0 0 07/2812155449poor100X0 0 0 0 0 08/1316206358excellent200XX00 000 08/2511155244good300X00 00 0 09/417155344good50X0 00 0 0 09/2516005548good100XX1010 0 0------------------------------_.-----------------------------------------------------------------------------------------------147/2317356851excellent100X00 000 07/3016006351excellent600X00 0 0 008/712306249excellent1000X0 0 0 0 0 08/1316005947excellent500X000 0 0 08/2511005545good200X0 00 0 0 09/416306047good1000X0aaa0 0I.D9/2515305746excellent200X00 000 0I.D-.__.-------------------------------------------------------------------------------------_."------------------------------------lS7/2317006851excellent00 00 0 007/2913006652excellent3500X00 0 0 0 08/812056256excellent3000X0000 0 08/1407455047good500X0a a0 0 09/610304445good01 0 1 0 009/2410304846good7X0a a0 0 0------._-----------------------------------------------------------------------------------------------------------------------167/2316456856fair00 0 0 0 0 07/2913306649poor0000 00 08/813206145excellent10Xa0 0 0 0 08/1408155343good10X00 0 0 0 08/2616155448good0120120 0 09/611104747good00 0 000 09/2411105245good10 0 0 0 0 0-------------------------------------------------------------------------------------------------------------------------------177/2316307652excellent00 0 0 0 0 07/2913406457good1500X0 00 0 008/1408455340good00 0 0 0 0 08/26163056439OO~00 000 0 09/6--------poo09/2411155046good2500 00 0 0 AppendixTable6.EscapementsurveycountsconductedontheSus1tnaRiverinSloughsNumbers18,19,20,21,Devl1'sCanyonProject1975.FrySpeciesIdentifiedTemperature.r=AdultSalmonDensityC'>IIIC--SloughNo.DateTime(oF)SurveyNo.Fry--....ChumSockeye....QJ(mllitary)AirWaterConditionsObservedc:n0e>,+.>LiveDeadTotalLiveDeadTotalc.c::I'"'-....0.cl-s:::w::uuc:J3:187/2914006253poor0a0 0 0 0 08/1409205646good00 0 0 0 0 08/26164556479OO~00 0 0a009/6--------poo9/2411455445good100 00000--------------------------------------------------------_.--_.------------------~----------------------------------------------197/2309005944poor00 0a00a7/2914156248poor00 000 0a8/1011255649fair00a0 1a18/1409505842excellent0aa a a0a8/2617005443goodaa0 020020......9/611354542good0a aa12012C>C>9/2412005245good200aa10313------._-------------------------------------------------_.--------------------------------------------------------------------207/2309155944poor00 0 0 00 07/2914256249poora0 0 00 008/1012205443excellent500X XX0U00 0 08/1410206043excellent300X X00 00008/2618005444exce11ent200XX0 0o·0 0 09/6122047 44good200XX000 0 0 0._--------------------------------------------------------.----------------------------~---------------------------------------217/2309406250poor00 00 0 0 07/2914406248poor00a00 0 08/1a13306144fair500X X0 0 0 00 08/1411206048good500X X0 0 0 00 08/2618305446poor150X0 0 00 009/613004645good300X250146396360369/2514005448excellent09234126492675--JJSloughareadriedup.1 1AppendixTable7.EscapementsurveycountsconductedontheSusttnaRtverfnWhfsker'sCreek,ChaseCreek,LaneCreek,McKenzfeCreek,FourthofJulyCreek,IndianRfverandPortageCreek,Devfl'sCanyonProject,1975.TemperatureAdultSalmonDensityLocationDateTime(OF)SurveyNo.Fry~ChumSockeyeKingPink(llf11tary)AirWaterConditionsObserveLiveDeadTotalL1veDeadTotalLiveDeadTotalLiveDeadTotalI/htsker's7/2314306555poor15000 0000 0325000Creek7/2812456050poor15000 000 0 010 1 0 0 08/417106856poor150000 0 0 0 02212300 08/1413206655poor1500000 0 0 0 3 1 4 0 0 08/2316506054poor150000 0 0 00 0000009/312305649geod0 00 0 00 0 00 00 00---------------------------------------._---------------..-----------.-._._---------------------------------.---------------------------------------Chase7/1712355958poor15000 00 00 0 0000 00Creek7/2514455857poor150000 00 0 0 0000 0 08/213106058poor15000 0 00 00 0 0 00 0 08/9131558 57poor150000 0 0 00 00 0'00 08/2217256157poor150000 000 000 0 0 009/315156054good011000 0 00 0 0 00---._----------------------------------~---_._---------------------......-_._---._._--------.---------------.---------------------------------------Lane7/2113307047excellent00 0 0 0 0 0 0 0 0 0 0 0Creek7/2615455649excellent00000 0 0 0 0 0200208/612455547exce11ent1000 0 0 00 0101810818/1717005949excellent0 30 3 00 0 00 010621088/2712205748excellent0 1 0 10 00 00 02S21469/317005S46excellent0 0 0 0 0 0 0 00 0241439/2714155545poor000 0 0 0 0 0 0 0 0 0 0-'--------------------------.------------------~~----------_._---------..---------.....---_._---------------------_.._----------------_._--_..--------0Hc.Kenzfe8/614106049excellent25000 0 0 00 000000--'Creek8/1716305953excellent2500 00 00 0 00 00 008/2712005449excellent0 0 0 0 000 0 00 00 09/814005148good2000 0 030 3 0 00 0009/2713005446exce11ent0 0 00451460 00 000-------------~-----------------------_.~---.-----~~--~------------------------------------------------------------------------------------------_..-Fourth7/2816?06346excellent00 0 00000 0 040040ofJuly8/916006656excellent00 0 0 0 0 0101.87087Creek8/1711306553excellent0 0 0 01010 0 014831518/2515006055exce~)ent0 0 0 0 0 0 0 0 0 0101701719/809454345poor_------ - --- - -- ---9/2710305046fair000 0 000 0 00 0 00--------------------.-------------------------.----------_._-------------------------------------------------.--------------------------------------Indian8/91800----good0 1 01 0000 0 04 04River8/1214157657excellent0700700001081832103219/61400-- --poorY-------------9/2610305745fair016 7101 0 0 000 0--------------------------------------------------------------------------------------------------------------------------------------------------~-Portage7/2310307848excellent0 0 000 0020200 0Creek7/2917005447excellent00 00 00 0250250008/1014005850good00,00 000 3 0 3 00 08/2412005247exce~lent000 0 000 00 000 09/61330----poorJyAllfrypresentwerecohosalmon.yWhftewaterconditionspreventedsurveys. tAppendixTable8.EscapementsurveycountsconductedontheTalkeetnaRiverinSloughsNumbers1,2,3,4,5,and6,Devil·sCanyonProject,1975.FrySpeciesIdentified:t:0'1onTemperatures::.....AdultSalmonDensity.........SloughNo.DateTime(oF)SurveyNo.Fry....<1.1ChumSockeye0'10E>0+>(military)AirWaterConditionsObsel'veds::.c~10.....LiveDeadTotalLiveDeadTotal.....0.c~.c:..::uu(,!):3:7/2513006349excellent3500X000 0 0 08/51030-6947excellent1500X00 0 0 0 08/1910155549excellent3000X0 0 0 0 0 09/2.09455446good3000X0 0 0 0009/912005045good2000X0 0 0 0 0 0-.-----------------------------------------------------------------------------------------------------------------------------2·7/2517355748excellent300X000 0 0 08/514007755excellent1500X0 000 0 08/1913506455excellent00 00 00 09/212055847good4X1501500 0......_______a__________••___________________________________________________________________________________________________________037/2517505752poor0000 00 0N8/515057550excellent1400X00 0 00 08/1915306354poor00 000 009/212355449excellent06 0 6 0 0 0-----------------------------------------------~-------------------------------------------------------------------------------47/251830GO48poor1/00 00 0 0 08/51550-- --poor-00 00-0 0 0-------------------------------------------------------------~-----------------------------------------------------------------57/2514105849excellent300X000 0008/517155954excellent20000 0 0 08/1910505755goodZ/00000 009/21020----poor-'-.-----------------------------------------------------------------------------------------------------------------------------67/2515005746excellent3000X00 00008/517306948exce11ent500X00 00 0 08/1911055947good3/1500X0 000 0 09/210405646good}"!300X0000 0 09/912254847good-1000X0 0000 0-.._--------------------------------------------------------------------------------------------------------------------------- ,:.AppendixTab'e8.EscapementsurveycountsconductedontheTalkeetnaRiverinSloughsNumbers7,8,and9,Dev11·sCanyon.Project,1975(cont.).SloughNo.TemperatureDateTime(OF)Survey(mi11tary)A1rWaterConditionsFrySpeciesIdentified.t::01IIIAdultSalmonDensitys::........\f-No.Fry01....QlChumSockeye0E>.+oJLiveTotalLiveTotalObserved.~.r::l10....DeadDead0.r:I-.r:~u uCJ:;I:.....aw77/2515005746excellent1000X0 0 0 0 0 08/517456947excellent50X0 0 0 0 0 08/1911305748good3/2000X0 0 0 0 0 09/211455749good3/400X0 0 0 0 0 09/913254847good-500X0 0 0 0 0 0---------------------------------------------------T7.--------~----------------------------------------------------------------88/51220----poor------ - - - - -------------·---·-------·---------------~----------T7--------------------------------------------------------------------------97/251700,5849poart/----- - - - - -8/51240-- --poo~----- - - - - -!IThema1nstemTalkeetnaR1verflowingthroughtheslougharea.l!Thesloughareacompletelydriedup.~Themouthandsectionsofthesloughareadriedup. AppendixTable9.EscapementsurveycountsconductedontheTalkeetnaRiverinBeaverPond,Railroad.OldChannel.Whiskey.ClearCreekSloughs.andWiggleCreek.Devi1'sCanyonProject.1975.FrySpeciesIdentifiedSloughTemperatureDateTime(OF)Survey(military)AirWaterConditions..cClIIIs:::....AdultSalmonDensity.........No.Fry~wChumSockeyeC'I0e>,.....Observeds:::..c::Ito....LiveDeadTotalLiveDeadTotal....0..c~.s:::~uuC):.;~igg1e7/2518005957excellent00 0 0 0 0 0Creek8/515307659excellent1000X0 0 0 0 0 08/1915356657good1500X0 0 0 0 0 09/213005549good00 0 0 0 0 0---------------------------------------------------T7--------------------------------------------------------------------------Beaver7/2518206048poorr/----- - - - - -Pond8/515407548poo~----- --- - -Slough9/213505749good00 0 0 0 0 0-----------------..--------------------------------------------------~---------------------------------------------------------o.0o0--'o.j:::oRailroadSloughOldChannel8/199/28/5154513301600655572585559poorgoodfairooooooooooooooooo-------------------------------------------------------------------------------------------------------------------------------Whiskey7/25160057 52'excellent3000X0 000 0 0Slough8/512006452excellent3000X0 0 000a8/1912206555good4000X50050'0009/211005751good2000X0 000009/914155048good200X808303------------------------------------------------------------------------------------------------.------------------------------Clear8/513007554exce11ent60000000 0Creek8/1912456352excellent2000X XX0 00 00 0Slough9/211305447good09/915004845good013921160000l/ThemainstemTalkeetnaRiverflowingthrough'theslougharea. APPENDIX II I NOTES ON THE r10RE Cm1~10N BENTHIC INVERTEBRATES FOUND IN THE SUSITNA RIVER TRIBUTARIES Insecta All of the insects collected in the Susitna River sampling sites were larval or pupal forms of insects that are terrestrial in the adult stage. The major portion of the life history usually occurs in the aquatic environ- ment.The adult stages often emerge and live as a terrestrial insect for only a few days.In some instances the adult has no mouth parts (Ephemeroptera). It emerges,carries out the reproductive functions,and dies in two or three days.The juveniles stages of an aquatic insect may last from several months to three years,as with Plecoptera.It is during this developmental stage that all growth or increase in biomass occurs. Plecoptera (stoneflies) Stonefly nymphs are strictly aquatic and are found in debris,masses of leaves and algae,and under stones in every kind of lotic environment where there is an abundance of dissolved oxygen.They form an important portion of the diet of fish,especially for members of the trout family. and are commonly found in clear,cool,streams where little organic enrich- ment occurs (Reid,1961;Pennak,1953). Ephemeroptera (mayflies) This order of insects is found in all types of fresh water where there is an abundance of dissolved oxygen.The nature of the substrate and the rate of water movements largely determines the species composition.They are all herbivores,very sensitive to temperature changes,and one of the most important sources of fish food (Pennak,1953).They will not survive even a short-term oxygen depletion (Beeton,1961). Tricoptera (caddis flies) Larval and pupal forms of caddis flies are aquatic and are found in all types of freshwater habitats.'~st species of this order build a case of rocks or organic debris.These cases mayor may not be attached to the substrate.The larvae and pupa are an important source of fish food and require an adequate supply of dissolved oxygen.The species composition is affected by rate of flow and the nature of the substrate (Pennak,1953). In swift flowing streams most larqe concentrations of caddis fly larvae are associated with gravel or cobble bottoms (Hickin,1968). Diptera The Diptera are highly specialized two-winged flies and include common insects such as the horsefly,mosquitoes and midges.Many families have aquatic immature stages,althouqh adults are never found in the aquatic 105 environment.Representatives of two families,Simu1iidae and Ceratopoqonidae, were identified in the Susitna River tributary streams. Simu1iidae (black flies) Black fly larvae are usually abundant in shallow,swift streams where an abundance of oxygen occurs.They are a1\~ays attached and feed on plankton and detritus (Pennak,1953). Ceratopogonidae (biting midges) This family of insects is commonly referred to as "no-see-ums.1l The larvae are most commonly found in floating masses of algae,but also occur in springs,streams.and wet mud along shores (Pennak.1953). 106 APPENDIX IV The Alaska Department of Fish and Game has been requested to assign monetary values to the Susitna River salmon stocks by the Corps of Engineers. These figures will provide a basis for mitigation actions.Total escapement figures are not available for this system and it is therefore difficult to assign a value to the salmon populations.The following has been compiled by Commercial Fisheries staff biologists to partially fulfill the request. It must be emphasized that final figures are only estimates based on feelings of biologists familiar with the Susitna Basin area and do not represent fact. The estimated maximum sustained yields (MSY)for salmon produced in the Cook Inlet gill net districts,i.e.,that area north of the latitude of Anchor Point,based on historical catch trends are: sockeye king pink chum coho 1,700,000 66,000 1 ,800,000 700,000 300,000 The percentage of salmon produced from the Susitna River basin is estimated to be: sockeye king pink chum coho .50 x 1,700,000 =850,000 .90 x 66,000 =59,400 .85 x 1,800,000 =1,530,000 .90 x 700,000 =630,000 .70 x 300,000 =210,000 If we assume the above is relatively correct and we relate this to: 1.The average weights of adult salmon by species,i.e., sockeye 6.1 1bs.;king 25.0 1bs.;pink 3.5 1bs.; chum 7.4 1bs.;and coho 6.1 1bs. 2.The average 1975 prices paid to fishermen per pound by species,i.e.,sockeye $0.63,king .62,pink .36, chum .43,and coho .47. Then: Susitna Production x Average Weight x Average Price/lb.Value to Fishermen Sockeye 850,000 6.1 .63 $3,266,550 King 59,400 25.0 .62 920,700 Pink 1,530,000 3.5 .36 1,927,800 Chum 630,000 7.4 .43 2,004,660 Coho 210,000 6.1 .47 602,070 The estimated average annual value to fishermen is therefore approximately $8,721 ,780. 107 ----------_._._._._._.•..--------_. This value does not include the value of salmon it takes to produce the estimated catch produced in the Susitna basin.This may be calculated by using estimated return by spawner by species using the 1975 price per pound paid to fishermen: - Species Sockeye King Pink Chum Coho Return/Spawner 3.0:1 1 .0:1 3.8:1 2.2:1 2.2:1 Value of Spawners Spawners/MSY 283,333 59,400 402,632 286,364 95,455 Average PriceAverageHeightSpecies Sockeye King Pink Chum Coho Average annual 6.1 25.0 3.5 7.4 6.1 value of spawners .63 .62 .36 .43 .47 -Spawners Value--- 283,333 $1 ,088,849 59,400 920,700 402,632 507,316 286,364 911 ,210 95,455 273,670 $3 ,7ol ,745 The 1973 average estimated market values of drift gill net vessels and gear were $12,843 and $2,411,respectively.The maximum number of drift gill net units participating in the Cook Inlet fisheries is 625. With a potential loss of a portion or all of the above Susitna River pro- duction this investment will constitute a potential loss. Based on the same 1973 estimates,set gill net gear and sites were valued at $8,223 and $21,563 respectively,or a total of $29,786 per set net fisherman.The maximum number of set gill net units participating in the fishery is 525.As with the drift gill net fishery a portion or all of this investment represents a potential loss. Other areas of interest would obviously be affected should a drastic decline in salmon production occur.These include,but are not limited to: (1)sport fishermen and supporting services;(2)salmon processing facilities and seasonal employment;(3)State tax of the commercial cannery salmon pack of Cook Inlet;(4)licensing revenues;(5)a variety of commercial fishermen and industry supporting services;and (6)cutback in the numbers of fishermen participating in the fishery by the Commercial Fisheries Entry Commission accomplished through the "buy-back program"costing the State funds. 108 - PRE-AUTHORIZATION ASSESSMENT OF THE SUSITNA RIVER HYDROELECTRIC PROJECTS: PRELIMINARY INVESTIGATIONS OF WATER QUALITY AND AQUATIC SPECIES COMPOSITION SPORT FISH SECTION BY JAMES C.RIIS FISHERIES BIOLOGIST ALASKA DEPARTMENT OF FISH AND GA~E SPORT FISH DIVISION ANCHORAGE TABLE OF CONTENTS Page No. LIST OF TABLES i i L1ST OF FIGURES i v INTRODUCTION 1 STUDY AREA 2 MATERIALS AND IVIETHODS 2 RESULTS AND DISCUSSION 3 FISHERIES 3 BENTHOS 8 LIMNOLOGY 11 CONCLUSION 44 ACKNOWLEDGMENTS 44 POTENTIAL IMPACTS 45 RECOMMENDATIONS 47 LITERATURE CITED 49 APPENDIX 50 ..... i - Number 1 2 3 4 5 6 7 LIST OF TABLES Title Results of Winter Fry Sampling in t1ainstem Susitna, Devi1 t s Canyon Project,1975. Fish Collected in Sloughs Between Talkeetna and Portage Creek,Devil 's Canyon Project,1975. Age Analysis of Grayling Sampled from Portage Creek, Devil's Canyon Project,1975. Length Variation of Grayling Sampled from Portage Creek,Devi1 's Canyon Project,1975. West Side Susitna River Chinook Salmon Escapement Surveys,1975. East Side Susitna River Chinook Salmon Escapement Surveys,1975. Aquatic Invertebrates Collected in Clearwater .Tributaries of the Susitna River,Devil's Canyon Project,1975. Page~ 5 7 9 9 10 - 10 12 8 9 10 11 12 13 14 Aquatic Invertebrates Collected in Susitna River, Devi1 's Canyon Project,1975. Maximum and Minimum Daily Water Temperatures from the Susitna River at Parks Highway Bridge,Devi1 's Canyon Project,1975. Maximum and Minimum Daily Water Temperatures from Willow Creek,Devil's Canyon Project,1975. Maximum and Minimum Daily Water Temperatures from Birch Creek,Devil's Canyon Project,1975. Highest,Lowest,and Mean Values of Limno1ogical Data Collected from the Susitna River and Seven Tributaries of the Susitna River Between and Including Willow and Montana Creeks,Devil 's Canyon Project,1975. A compilation of U.S.Geological Survey Limnological Data of Specific Concern,Collected from Susitna River Tributaries,l"1ontana,Sheep,and Casvlell Creeks,Devil's Canyon Project,1975. Water Quality Analysis of Samples by U.S.Geological Survey Central Laboratory in Salt Lake City,Utah, Collected March 25,1975 from the Susitna River at Sunshine,Devil 's Canyon Project,1975. i i 13 17 18 19 21 23 24 .... ... List of Tables (Cont). Number Title Page No. 15 Compiled Data of Interest Collected by U.S.Geological 24 Survey from the Susitna River at Sunshine,Devil '5 Canyon Project,1975. 16 Limnol ogi ca 1 Data Collected on Four Tributaries of the 41 Susitna River between Talkeetna and Devil Canyon,Devil's Canyon Project,1975. 17 Limnological Data Collected from the Susitna River 41 Immediately Upstream from Gold Creek,Devil '5 Canyon Project,1975. 18 Li mn 0 1og i cal Data Collected from the Susitna River 41 Immediately Upstream from Portage Creek,Devil I 5 Canyon Project,1975. 19 Limnological Data Collected from Fifteen Sloughs 42 Along the Susitna River Between Talkeetna and Portage Creek,Devil '5 Canyon Project,1975. 20 Limnological Data Collected April 24,1975 from the 43 Impoundment Area of the Susitna River near Jay,Watana, and Deadman Creeks,Devil's Canyon Project,1975. iii LIST OF FIGURES Number Title 1 2 3 4 5 6 7 8 9 10 11 Daily Water Temperatures of the Susitna River Approxi- mately Three Hundred Yards Downstream from the Parks Highway Bridge,Devil's Canyon Project,1975. Maximum Daily Water Temperatures of Birch Creek Approximately Five Hundred Yards Upstream of the Alaska Railroad,Devills Canyon Project,1975. Maximum Daily Water Temperatures of Willow Creek Approximately Two Hundred Yards Upstream of the Confluence with Deception Creek,Devil IS Canyon Proj ect,1975. Limnological Data Collected from the Susitna River at the Parks Highway Bridge,March 26 to August 18, Devil IS Canyon Project,1975. Limnological Data Collected from Montana Creek at the Highway Bridge,March 26 to August 18,Devills Canyon Project,1975. Limnological Data Collected from Sheep Creek at the Highway Bridge,March 4 to August 18,Devil1s Canyon Project,1975. Limnological Data Collected from Goose Creek at the Highway Bridge,March 4 to August 18,Devil's Canyon Project,1975. Limnological Data Collected from Caswell Creek at the Highway Bridge,March 26 to August 18,Devil's Canyon Project,1975. Limnological Data Collected from Kashwitna River at the Highway Bridge,April 24 to August 18,Devil's Canyon Project,1975. Limnological Data Collected from Little Willow Creek at the Highway Bridge,April 24 to August 18,Devil1s Canyon Project,1975. Limnological Data Collected from Willow Creek at the Highway Bridge,March 26 to August 18.Devills Canyon Project,1975. iv Page No. 14 15 16 25 &26 27 &28 29 &30 31 &32 33 &34 35 &36 37 &38 39 &40 - - Pre-authorization Assessment of the Susitna River Hydroelectric Projects: Preliminary Investigations of lVater Quality and Fish Species Composition. ABSTRACT Biological investigations of the Susitna River and selected tributaries were conducted from February 10,1975 to September 30,1975 to obtain base- line data regarding indigenous fish populations,available aquatic habitat, and water quality which will aid in the definition of biological areas of concern requiring additional study prior to authorization of hydroelectric development by the U.S.Anny Corps of Engineers. INTRODUCT ION Anadromous fish stocks of Cook Inlet and the Susitna River drainage,the largest fresh water system in Cook Inlet,have historically been of great value to the economy of Southcentral Alaska. Canmercial fishing has been tile principle use of the anadromous fish resource,but in recent years,both anadromous and resident fresh water fish species indigenous to Upper Cook Inlet and the Susitna River system have become increasingly important to the recreational user. TIle direct cunulative value to recreational and commercial fishermen, and indirect values to the many and varied supportive services and communities dcriving benefit,makes the fishery resources of the Susi tna River an extremely valuable resource. The salmon stocks utilizing the Susitna River drainage,particularly the chinook (Oncorhynchus tshawyts ch a),and coho salmon,(0.kisutch),are currently at depressed levels.Chinook salmon stocks have~een the target of extensive commercial and recreational fishing closures since the early 1960's.Management of these stocks is currently at a most important,if not critical,stage.The proposed hydroelectric development of the Susitna River basin will have a number of identifiable,and currently undefined, effects upon the existing quality of water and aquatic }labitat necessary for perpetuation of the anadromous and resident fish species. The U.S.Army Corps of Engineers has stated downstream Susitna River flows will be significantly altered by regulation,existing seasonal patterns of silt and sediment transport will be different,stream temperatures and water quality parameters may be affected,and 50,500 acres,including 82 river miles,of natural stream will be impounded by the Devil-Watana dam impoundments. The United States Fish and Ivildlife Service,pursuant to provisions in the Fish and Wildlife Coordination Act and the "Cooperative Agreement between the Service and the State of Alaska,Department of Fish and Game"provided funding to the Sport Fish Division (Alaska Department of Fish and Game)in the amount of $8,000 during the period July 1,1974 to June 30,1975,and $16,000 during the period July 1,1975 and June 30,1976 for biological surveys and studies of the Susitna River basin. 1 ---------------"---"------,,--------- With the available funds study objectives were to:1)determine resident and anadromous sport fish species present and their distribution in the main- stem Susitna River,its tributaries,and peripheral slough areas;2)measure chemical,physical,and biological parameters associated with the mainstem and important tributaries;3)determine the most acceptable sampling techniques for the highly variable conditions existing in the Susitna River; and 4)define future studies required to fully identify the impacts and effects of hydroelectric development upon the Susitna River fishery resource. Study results are discussed in the following text,conclusions presented where possible,and recoTIIDlendations made for further definitive biological investigations. STIJDY AREA The hydroelectric project under study will have major effects upon the Susitna River which drains an area of approximately 20,000 square miles.That portion of the river above the proposed Devil Canyon dam site drains approxi- mately 6,000 square miles.The Susitna River basin is bounded on the east by the Copper River plateau and the Talkeetna Mountains,on the west and north by the mountains of the Alaska Range,and on the south by the Talkeetna Mountains and Cook Inlet. The Maclaren,the Oshetna,and the Tyone rivers are the largest tribu- taries of the Susitna River above Devil Canyon.The Tyone River is the only one of the three which is non-glacial.There are munerous smaller tribu- taries which fluctuate greatly in seasonal rate of flow,but remain silt free or clear throughout the year. The Susitna River tributaries below Devil Canyon,for the most part, originate in the surrmmding mountains.The Chulitna,Talkeetna,and Yentna are the major tributaries,all of which are glacial.Clear water tributaries below Devil Canyon collectively exert considerable influence and are the major fish producing waters in this system.The major non-glacial tribu- taries include:Portage Creek,Indian River,Montana Creek,Goose Creek, Sheep Creek,Little Willow and Willow Creeks,Deshka River,and Alexander Creek. The work described in this report was conducted on the Susitna River primarily from Portage Creek (located approximately three miles below Devil Canyon)downstream to the mouth of the Yentna River. One field trip into the upstream impoundment area during late winter was accomplished to attempt the capture of mains tern residing fish.Time and budgetary restraints precluded additional field studies in the upstream impoundment area during the 1975 summer field season. MATERIALS AND METHODS Travel to and from sampling sites during the winter was accomplished via a fixed wing aircraft on skis.A 20-foot riverboat,powered by an 8S horsepower outboard,was used to travel on the Susitna River during the ice- 2 - - - - free months.Chinook salmon escapement cOlUlts were made with the use of fixed wing aircraft (supercub),Bell-47 helicopter,and grmmd surveys. Adul t and rearing salmonids were collected with gill nets,minnow traps, set lines,seines,dip nets,rod and reel,and electroshocker. Benthic invertebrates were collected with artificial substrates which consisted of wire vegetable baskets lined with nylon screen cloth and filled with rocks taken from the stream bed.The baskets were left in the water for a period of approximately 30 days.A hand screen was also used to collect benthos samples. "In situ"analysis of alkalinity as caCo ,total hardness and pH on samples from the Susitna River and the seven ~ast side tributaries below the Parks Highway Bridge was perfonned at biweekly intervals,using a Hach chemical kit,Model Al-36B.Samples were collected approximately one to three meters from the bank,at or near the surface.Temperatures at sample collection points were recorded from just below the surface. Conductivity and turbidity samples for the Susitna River and the seven east side tributaries were collected at the same time as the above samples, placed in one-liter polyethylene bottles,and analyzed at the U.S.Geological Survey,Division of Water Resources Laboratory,using the Hach 2l00A turbidmeter and a Beckman RB3 conductivity meter.All conductivity measure- ments were standardized at 25OC. All thennographic data collected from the Susitna River and two tribu- taries were gathered using a Ryan thennograph model D-30,which was reset every 30 days.Temperatures were recorded in Fahrenheit on thennograph tape. The Susitna River water quality parameters from upstream of the Parks Highway bridge were gathered using a Hach chemical kit model DR-EL/2.Two sample sites were used;one approximately SO meters above Portage Creek and the other about 150 meters above Gold Creek.All samples were collected approximately five to ten meters from the bank,at or near the surface.Re- stricted access and limited time prohibited more extensive data collection during the field season. The Susitna River sloughs and tributaries between Devil Canyon and Talkeetna were also analyzed with Hach chemical kits,model DR-EL/2 and Al-36B.All measurements were made approximately two to five meters from the bank and SO meters from the mouths of the sloughs,at or near the surface. Temperatures were recorded in Fahrenheit to the nearest whole degree and later converted to the nearest 0.50 centigrade. RESULTS AND DISCUSSION FISHERIES Interviews with staff members provide evidence of resident and rearing anadromous salmonid fishes migrating downstream from the tributaries into the mains tern Susitna River during the fall,and back ups team into the tributaries during the spring.A hypothesis was fonmlated that this migration occurs in 3 part because of severe icing conditions and reduced flaws in the tributaries during the ''linter months,which rlaY result in 1)territorial displacement of certain species and sizes of fish,and 2)winter habitat preferences,i.e., Arctic grayl ing (Thymallus arcticus)appear to prefer larger bodies of water during the winter,substantial space and,in r.eneral,a higher qllality environment may be provided for afluatic species.Concern about this undefined Dligration is the basis for designing a biological and limnological study the included the tributaries as well as the rlainstem Susi tna River. The Commercial Fish Division initiated studies in 1974 on the sloughs and mainstem Susitna River from the Chulitna River upstream to Devil Canyon (Barrett,1974).This work was continued and expanded into the Talkeetna and Omli tna Rivers (Friese,1975).It was not the intent of the Sport Fish Division to duplicate work conducted by Barrett and Friese,but to supple- ment it ''lith lirmological data and to further study resident species and habitat areas not included in their prior and on-going studies. The numbers of fish and/or species collected during the fishery studies are not statistically significant in that the smnple sizes or numbers collected are inadequate to define specific population sizes.The samples obtained are important,however,as they document the presence of a mnnber of fish species,seasonally,in both the Susitna River mainstem and tribu- tarv waters. The seasonal fisheries investigations have provided considerable insight into 1)the extreme difficulty in assessing either summer or winter mainstem Susi tna River fish stocks due to high flows carrying debris and extreme ice and snow conditions respectively,and 2)future study requirements necessary to determine the significance and extent of the intra-system migrational phenomenon exhibited by resident and anadromous fish species. Winter: \'linter investigations to document the presence of rearing salmonid fry in the mainstem Susi tna River began February 10,1975 and continued through April,1975.The mainstem Susi tna River was sanpled with minnow traps, r,ill nets,and electroshocker at 11 locations between Susitna station and the Parks Higln'lay Bridge,a distance of approximately 50 miles,and two locations above Devil Canyon.Studies conducted during March and April, 1975 documented rearing coho,dlinook,chum,(0.keta),grayling,sculpin (Cot t~cognatus),burbot (Lota Iota),whi tefiS'h ~egonus_3:')and sucker (Catostomus catostomus)over-winterin~in the mainstem Susitna River down- stream from the ParkS Highway Bridge (Table 1).The sampling sites and dis- tribution findings are also plotted on aerial photographs in the Appendix of this report. Minnohl traps were installed in ~1ontana Creek,near the three forks, and Willow Creek,under the highway bridge,during the first week of April, 1975 when water with enough depth under the ice could be found to effectively fish a trap.Prior to this date,difficulty was experienced in finding sufficient water levels under the ice to set minnow traps in the tributaries. Five Dolly Varden (Salvelinus malma)ranging from 85 mm to 142 rom were trapped in Willow Creek and four Chinook fry ranging from 48 rrrrn to 74 mm were captured in Montana Creek. 4 - Table 1.Results of Winter Fry Sampling in ~!ainstem Sllsitna River,Devills Canyon Project,1975. Date Feb.10 Mar.18 Mar.19 Mar.25 Apr.10 Apr.23 Apr.28 Apr.30 Location Directly off mouth of Sheep Creek 2.3 miles south of Montana Creek 2 miles south of Kashwi tna River Directly off mouth of Deshka River Directly off mouth Montana Creek Directly off mouth Caswell Creek 2.2 miles north of Willow Creek 100 yards down- stream Jay Creck 100 yards dO\\'D- stream Deadman Cr. 50 yards upstream Montana Cr.mouth Susitna Station 3 miles south of Parks Hwy.Bridge Sampling Method 6 ~Iinnow Traps 6 Minnow Traps 6 MinnO\'J Traps 12 Minnow Traps 8 Set Lines 4 Minnow Traps 6 Minnow Traps 25 Minnow Traps 12 Hinnow Traps 1 Gi 11 Net 6 Minnow Traps 1 Gill Net Electroshocker Electroshocker Electroshocker Hours Sampled 24 72 72 48 48 48 48 192 48 48 24 24 Number and Species Captured o 2 SS 1 S 1 SS a o o 3 KS o o o o 7 CS 1 GR 1 WF 1 BB 1 S 1 SC *SS -coho salmon,KS-chinook salmon,CS-ch~m salmon,S-sucker,GR-grayling, WF-whitefish,BB-burbot,SC-sculpin 5 Minnow traps and gill nets were installed in tIle mainstem Susitna River above Devil Canyon from April 21 to April 24,1975.A gill net and 12 minnow traps were stationed 100 yards downstream from Jay Creek for 24 hours with negative results.Six traps and one gill net ,{ere placed 100 yards downstream from Deadman Creek for 12 hours,also without capturing fish. The most successful winter sampling technique for the Susitna River appeared to be the backpack electroshocker.Hrn~ever,this technique is limited to late winter after certain areas become ice free and before high silt laden flows begin.Minnow traps were not as effective during the winter as during the summer because fish are lethargic in cold water and may not enter the trap as readily.Thus,samples collected may not be indicative of fish numbers present at any given site.There is a need for testing of more effective trapping or fish collecting devices during the winter season. Summer: Summer investigations of fish species inhabiting the rnainstem Susitna River began June 17,1975.Following a reconnaissance and general familiari- zation trip to identify potential sampling sites,a base camp was established on the Deshka River near the confluence with the Susitna River.Beginning the week of June 23,1975,a crew of two biologists spent four days each week through July,1975 sampling for rearing fish in the mainstem Susitna River from the Parks Highway Bridge dm..'llstream.The results of this five week sampling period indicate the following:1)Anadromous salmon fry,rainbow trout,and grayling are scarce in the silt laden water of the mainstem Susitna River during this time of year and,2)whitefish,sculpin,and suckers were commonly captured in the turbid Susitna River.Two coho fry,50 and 69 mm in length,were captured at a sandbar near the mouth of Sheep Creek and two chinook fry,59 and 60 rom in length,were collected downstream of Willow Creek.With the exception of these four fry,no other salmon fry, rainbow trout,or grayling were captured in the Susitna River when the silt load was high.The reasons for the scarcity of salmonids in the mainstem Susitna could be attributed to a preference for clearwater by these species and the outmigration of chinook and coho salmon smol ts,pink and chum salmon fry before sampling efforts were initiated.The only sampling techniques which proved feasible for collecting fry during the high flow period of the Susitna River were hand seines and dip nets.Gill nets were ineffective because of drifting debris in the river during the high summer flows.The backpack electroshocker is also unsatisfactory when turbidity is high be- cause affected fish cannot be seen or captured. On August 6,1975 the base camp was moved from the Deshka River to Gold Creek.Sloughs in the Gold Creek area and upstream to Devil Canyon were sampled for fish in conjunction with the limnological study.Results of the fish collections are shown in Tm)le 2.Seining was conducted at four sites in the mainstem Susitna between Gold Creek at Portage Creek with negative results. Winter and summer observations of rearing fry in the Susitna River lend support to the hypothesis that salmonids migrate downstream from tributaries during the fall to overwinter in the Susitna and return to the tributaries during the spring. 6 .... - -, Table 2.Fish Collected in Sloughs Between Talkeetna and Port.age Creek) Devil's.Canyon Project,1975. Slough .Species Number Fish Date ""Number "'Collected .'Collected .'Site'(mm) Aug.13 11 Chinook 1 53 Grayling 1 56 Sucker 1 49 13 Grayling 1 46 Whitefish 1 37 Aug.14 IS Chinook 4 43-53 .16 Whitefish 1 50 19 Whitefish 5 39-45 Aug.IS 20 Chinook .10 52-66 Grayling 2 43~62 21 Grayling 2 56~58 Whitefish 5 39-48 .-Aug.19 17 Coho 2 39,48 Grayling 4 33-65 Burbot 1 59 Sucker 1 52 18 Chinook 4 51-55 Coho 4 39-54 Grayling 1 53 Whitefish 3 48-53 Bur bot 1 49 .Sucker 2 .47 ~54 ..'".": 7 Arctic grayling are the most common resident recreationally important species indigenous to the Susitna River Basin.Grayling occur in the majority of fresh water tributaries of the Susitna River,both upstream and downstream of the Devil's Canyon Dam site,and were documented specifically in those irrnnediate downstream tributaries of Portage and Fourth of July creeks,and Indian River. An age-length frequency of 33 grayling collected from Portage Creek is presented in Tables 3 and 4 as general indication of grayling size and age composition. Arctic grayling e~libit intra-system migrations and a need exists for comprehensive studies of these seasonal movements and their significance to determine the overall effects of the potential loss of any of their aquatic habi tat. All five species of salmon utilize the Susitna River and all are equally important.The Sport Fish Division recognizes dIe chinook and coho salmon as having the greatest potential for satisfying future recreational needs.The COJluuercial Fish Division studies pink,chum,and sockeye (Q.nerka)salmon and reported on these species in their section. A number of key tributaries of the Susitna River were selected for chinook salmon escapement during 1975 (Tables 5 and 6).It should be noted these escapement counts do not constitute total numbers,but indicate relative abundance and depict the importance of the Susi tna River as an avenue of access.IJpstream impoundment may affect the migration of fish into key spawning streams.Prior to impoundment the magnitude of anadromous sabnon escapements should be enumerated totally. Benthos Species diversity has become widely used as an indicator of water quality.Diversity indices may be applied to any hiotic community but have had widest application with the benthos.Such indices relate the number of kinds of organisms to the total number of organisms and to the number of individuals of each kind.Undisturbed natural communities are assumed to have a high diversity;that is,a relatively large number of species,with no species having disproportionately large mnnbers of individuals,(Lind, 1974).Diversity is considered to be a sensitive hioa~say fOT assessin? environmental stress (Cantlon,1969;Wilhm,1970).The diversity of a conununi ty is a meaningful parameter \'lhich can be measured (Warren,1971). Warren emphasized the importance of diversity in defining the environmental impacts of changes to a system.To properly assess impacts,a diversi ty index should be computed,using identical methodology,before,during,and after construction. In order to use a species as an indicator organism,its envirormlental requirements must be reasonably well defined within rather narrow limits (HcCoy,1974).It has been demonstrated that presence of srecies in the orders Ephemeroptera and Plecoptera in streams indicate unpolluted waters. Members of hoth these orders were observed on rocks in the impoundment area of the Susi tna River during the late \lfinter field trip,April 21 throw~h April 24,1975 and downstream of Devil Canyon throU,l:;hout the sumner. 8 - Tabls 3.Age Analy41.or Crayllpg Saopl&d fr~Poreaas Creek.D~vl1'. C"~YQn ProJect.Aus'ue 12.IH5. 30- !. u. 2n JtJ•... ~U.. 0..•1 ~ 10 ., .s I Table 4.L«nSth Varla~1I of Cn,.l1l:l1 5-,.1_f..-Portq.er-s.Onn".em"",Projeee, AU;ilUt U.1975. IU I 9 Table 5.West Side Susitna River Chinook Salmon Escapement,Devil's Canyon Proj ect,1975 .. Helicopter Stream Counts Deshka River System Alexander Creek -System Lake Creek System* Talachulitna River * Peters Creek* Canyon Creek* Total 4,737 1,878 281 120 14 2 7,032 Table 6.East Side Susitna River Chinook Salmon Escapement,Devil's Canyon Project,1975. Stream Willo\\'Creek Little Willow Creek Kashwitna River Sheep Creek Goose Creek f'.10ntana Creek Chunilna Creek* East Fork Chulitna River* Middle Fork Chulitna River* Prairie Creek* Indian River Portage Creek Helicopter Aerial Counts 103 33 101 Fixed Wing Aerial Counts 42 13 7 55 31 32 Ground Counts 177 229 369 Total Total All Counts 237 180 775 1,192 *Not a direct tributary to Susitna River;however,salmon must use the Susitna as a pathway to arrive at these rivers. 10 Benthic invertebrates were sampled during the sununer season with eight artificial substrates (Tables 6 and 7).Substrates were placed in the main- stem Susitna River one Inile upstream from the Deshka River,100 yarQ~upstream of Willow Creek,and :i.rronediately above Gold Creek.Waterfall Creek and Fourth of July Creek,which are clear water tributaries of the Susi tna,were also sampled.All locations with the exception of Fourth of July Creek were sampled with two artificial substrates for a period of 30 days.Fourth of JUly Creek was sampled by hand holding a screen (36"x 36")and stirring the substrate innnediately upstream.Aquatic insects collected in both the Susi tna and tributaries are typical of clean cold water streams in Alaska. Due to the restricted time fr<D1\e available for this study and report pre- paration,aquatic invertebrates are keyed only to family. Limnology TIle limnological study was initiated March 26,1975 establishing sample sites on the Susitna River and all major east side tributaries from the Parks Highway Bridge dOl'lnstream.Water samples were collected on a bi-weekly basis at the bridge crossings of eadl tributary.Parameters measured were water temperature,pt!,turbidity,conductivity,total alkalinity,total hardness,and dissolved oxygen. Temperatures were also monitored with Ryan Themographs C',10del d-30 0 F.) in the Susitna River,Rirch Creek,and l~illow Creek.It is interesting to note the similarity in temperature trends between the Susitna River and note the similarity in temperature trends between the St~itna River and tributaries (Figures 1,2,and 3).For example,both the Susi tna River and Wi 11rn'1 Creek measured 32 o P.on April 1,1975.A slow ,.,ranning trend was observed in both rivers until May 14,1975 when temperatures of both rivers were measured at approximately 34 0 F.A steady upward trend occurs after May 15 until the maximum temperature was reached in mid-July.The maximum water temperature in the Susitna River was 55.50 F.July 12,1975.Willow Creek exhibited a maximtim of 56 0 F.during the period July 7 through July 10,1975.Maximum and minimum daily water temperatures monitored by the thennographs are presented in Tables 9 and 10.The temperature remained relatively stable in both rivers between July 15 and August 30,1975,fluctuating between 48 0 F. and 53 0 F.TIle water temperature began to decrease by September 5,1975 and was 45 0 F.in both the Susitna River and Willow Creek on September 23,1975 when the thennographs were removed. East side tributaries of the Susi tna River downstream from the Parks Highway Bridge do not have lake systems present,but are the result of surface and subsurface runoff from the surrounding mountaiI)S-and foothills. Montana Creek,Sheep Creek,rJOose Creek,Caswell Creek,Kasoo.tna River,and Little Willow Creek temperatures were taken biweekly and trends were con- sistent with measurements of the Susitna River and Willow Creek (Figures 4-11). Birch Creek was selected as a thermograph site to collect tempr~ature data on a creek draining a lake.Birch Creek is the outlet of Fish Lake and empties into the Susitna River upstream of the Parks Highway Bridge.It also differed from the tributaries downstream of the Parks Highway Bridge by having less gradient and vohnne.Temperatures were considerably wanner in Birch Creek,as suspected,reaching a high of 69 0 F.on July 10,1975 (Table 11). Lentic environments have the capacity to retain heat,resulting in different thennal patterns than lotic environments.Lakes also act as a buffer by stabilizing fluctuating flows.The thennal pattenlS and stabilized flows in the outlets of lakes benefit productivity. 11 Table7.AquaticInvertebratesCollectedinClearwaterTributariesoftheSusitnaRiver,DevilCanyonProject,1975.I-'""LocationFourthofJulyCreekWaterfallCreekOrder--TrichopteraDipteriaPlecopteraEphemeropteraTurbellariaDipteraP1ecopteraEphemeropteraOligochaetaGastropodaFamilySericostomatidaeRhyacophilidaeRhyacophilidaePerlodidaePer10didaeHeptageniidaeBaetidaeType1Type2Type3Type4Type5Type6Per10didaeBaetidaeType1Type2No.14115763164110231711315Co1lectiortMethodHandScreenArtificialSub-stratebasket(2)CollectionDates:Aug13Aug7 -Sep7 ~.II I 1IItI I 1 1•••)iTable8.AquaticInvertebratesCollectedinSusitnaRiver,DevilCanyonProject,1975......wLocationMainstemSusitnaUpstreamfromGoldCreekMainstemSusitnaUpstreamfromWillowCreekrilainstemSusitnaUpstreamfromDcshkaRiverOrder.--TrichopteraDipteraPlccoptcraEphemeropteraOlgochaetaTricopteraDipteraEphemeropteraPlecopteraTricopteraPlccoptcraEphcmeropteraFamilyRhyacophilidaeType1Type2PcrloclidacPerlodidaeBaetidaeSericostomatidaeHeptageniidaeBaetodaePerlodidaeScricostomatidaePerloclidaeI-IcptageniidacNo.134I51I325781113CollectionMethod·ArtificialSub-stratebasket(2)ArtificialSub-stratebasket(2)ArtificialSub-stratebasket(2)CollectionDatesAug7 -Sep7Jul1 -Sop1Jul1 -Aug1 Figure1.Daily\VaterTemperatures(MonitoredwithaRyanThermograph)oftheSusitnaRiverApproximatelyThreeHundredYardsDownstreamfromtheParksHighwayBridge,DevilsCanyonProject,June20toSeptember23,1975.15.6oJ60.....~10.00SOQ).j.J'"0'M(1jQ)Hr-Ollr-'MCi.j.JH>=:r-Q)(llu~4.4040o.0OJ32ok-II\I•Apr1Hay1Jun1Jul1Aug1Sep1Note:TemreraturestakenpriortoJune20thwerewithathermometeronabi-monthlybasis. lFigure2.MaximumDailyWaterTemperatures(MonitoredwithaRyanThermograph)ofBirchCreekApproxi~?tP1yFiveHundredYardsUpstreamoftheAlaskaRailroad,DevilCanyonProject,April10toAugust30,1975.21.2°170°15.6°~60°....C)10.0°1.j..JU1"C",""roC)~..r::bj)l=:''""Q)50°.j..J~l=:.c:Q)rou~4.4°J40°·o0°I-'}Ol•......'/•1i"(Apr1May1Jun1Ju11Aug1Sep1 Figure3.MaximumDailyWaterTemperatureU1onitoredwithaRyanThermograph)ofWillowCreekApproximatelyTwoHundredYardsUpstreamoftheConfluencewithDeceptionCreek,DevilCanyonProject,April10toSeptember23,1975.15.0°...j60°.....0'\<!>10.0°50°"D01-'('(j'"'"'"'(j)b/)..c......I=:.j.J(j)I=:H(j)..cu{"jw...4.4°40°0.0°J32°1/l.£.---------,,-------ij----------rl--------.,-------........--------Apr1May1Jun1Ju11,IAug1Sep1 - Table .9.Haximum and ~Iinimum Daily Water Temperatures CF-"Ryan"Thermo- graph,~Iodel 0-30)from the Susitna River at Parks Highway Bridge, Devil Canyon Project,1975. ........ ... . . . Temperature Temperature Temperature Date Max..Min.Date Hax.Hin.Date Hax.Hin • Jun 20 49.0 Ju1 22 51.5 51.0 Aug 23 53.0 21 49.0 23 51.5 24 53.0 52.0 22 4'9.0 48.0 24 51.5 25 52.0 23 47.8 47.8 25 51.0 26 52.0 24 48.8 47.8 26 52.0 51.0 27 52.0 25 49.0 27 52.0 28 52.0 50.0 26 49.0 28 52.0 51.5 29 50.0 48.0 27 49.0 29 51.5 30 48.0 28 50.0 49.0 30 51.5 51.0 31 48.0 29 50.0 31 51.0 Sep 1 48.0 30 50.0 49.0 Aug 1 52.0 51.0 2 53.0 48.0 Ju1 1 49.0 2 52.0 3 53.0 49.0 2 49.0 3 52.0 4 52.0 48.0 3 49.0 4 52.0 5 52.0 49.0 4 49.0 5 52.0 51.0 6 50.0 48.0 5 49.0 6 51.0 7 48.0 6 50.0 .49.0 7 51.0 8 48.0 7 51.0 50.0 8 51.0 9 47.5 8 52.0 51.0 9 51.0 10 47.0 9 54.0 52.0 10 51.0 11 47.0 10 55.0 54.0 11 51.0 12 47.0 11 55.0 12 52.0 13 46.0 12 55.5 54.0 13 52.0 14 46.0 45.0 13 54.0 53.0 14 52.0 15 45.0 14 53.0 51.5 15 52.0 16 45.0 15 51.7 16 52.0 17 45.0 16 51.7 50.5 17 52.0 51.0 18 45.0 17 52.0 51.0 18 50.5 19 45.0 18 52.0 19 50.5 20 45.0 19 52.0 51.0 20 50.5 21 45.0 20.51.0 21 50.5 22 45.0 21 51.0 22 53.0 23 45.0 17 TABLE 10.Haximum and Hinimum Daily Water Ter.lperatures (OF_Ryan Thermograph, Model 0-30)from Willow Creek,Devil Canyon Project,1975. ,Temperature Tewperature Temperature Date Halt.~lin.Date Hax.Hin.Date ~lax.Hin. Apr 10 34.0 Jon 5 43.0 37.0 Jul 31 50.0 11 34.0 6 43.0 39.0 Aug 1 51.0 50.0 12 34.0 7 44.0 38.0 2 52.0 51.0 13 34.0 8 44.0 39.0 3 52.0 51.0 14 34.0 9 44.0 38.0 4 53.0 51.0 15 34.0 10 43.0 38.0 5 53.0 16 34.0 11 43.0 39.0 6 51.0 17 34.0 12 44.0 38.0 7 51.0 50.0 18 34.0 13 44.0 38.0 8 50.0 19 34.0 14 45.0 40.0 9 50.0 20 34.0 15 44.0 40.0 10 49.0 48.0 21 34,.0 16 44.0 11 49.0 22 34.0 17 44.0 12 49.0 23 34.0 18 44.0 13 49.0 24 34.0 19 44.0 14 51.0 49.0 25 34.0 20 45.0 44.0 IS 51.0 26 35.0 21 44.0 43.0 16 51.0 49.0 27 35.0 22 43.0 17 50.0 28 35.0 23 45.0 43.0 18 50.0 29 35.0 24 45.0 19 50.0 30 35.0 25 46.0 45.0 20 50.0 May 1 35.0 26 50.0 46.0 21 50.0 2 35.0 27 52.0 46.0 22 50.0 3 35.0 28 47.0 23 50.0 4 35.0 29 46.0 24 50.0 5 35.0 30 46.0 25'50.0 6 35.0 Jul 1 48.0 46.0 26 50.0 7 36.0 35.0 2 48.0 27 52.0 50.0 8 38.0 35.0 3 47.0 46.0 28 48.0 9 36.0 4 51.0 46.0 29 48.0 :;. 10 36.0 35.0 5 54.0 49.0 30 48.0 11 35.0 6 54.0 50.0 31 47.0 12 34.0 7 56.0 52.0 Sep 1 48.0 47.0 13 34.0 8 56.0 52.0 2 48.0 14 34.0 9 --56.0 53.0 3 48.0 IS 36.0 35.0 10 56.0 54.0 4 48.0 16 36.0 35.0 11 55.0 52.0 5 47.0 44.0 17 36.0 12 51.0 49.0 6 44.0 18 36.0 13 51.0 49.0 7 44.0 42.0 19 39.0 36.0 14 51.0 8 44.0 42.0 20 40.0 35.0 IS 50.0 48.0 9 44.0 42.0 21 38.0 35.0 16 52.0 48.0 10 44.0 42.0 22 38.0 36.0 17 52.0 11 43.0 23 42.0 37.0 18 52.0 51.0 12 45.0 40.0 24 42.0 39.0 19 51.0 49.0 13 44.0 40.0 25 38.0 36.0 20 50.0 49.0 14 43.0 41.0 26 42.0 36.0 21 49.0 IS 45.0 43.0 27 40.0 36.0 22 49.0 16 44.0 28 43.0 37.0 23 50.0 49.0 -17 44.0 29 42.0 36.0 24 50.0 18 44.0 30 42.0 36.0 25 50.0 19 43.0 31 46.0 35.0 26 50.0 20 45.0 43.0 Jun 1 43.0 38.0 27 52.0 50.0 21 44.0 43.0 2 42.0 40.0 28 52.0 22 45.0 43.0 3 42.0 38.0 29 51.0 23 45.0 44.0 4 42.0 38.0 30 50.0 18 _. Table II.Maximum and Minimum Daily Water Temperatures (OF_"Ryan"Thermo- graph,Model D-30)·from Birch Creek,Devil Canyon Project,1975. Temperature Temperature Temperature Date lvlax.~lin.Date'.~lax.~'ti.n .Date Hax.t-1in .. Apr 11 38.0 May 29 47.0 46.0 Jul 15 59.0 12 38.0 36.0 30 47.0 46.0 16 59.0 13 37.0 35.0 31 48.0 46.0 17 59.0 14 35.0 Jun 1 50.0 48.0 18 59.0 15 35.7 35.0 2 51.0 19 59.0 16 35.5 3 51.0 20 59.0 17 35.5 4 51.0 21 59.0 57.0 18 35.7 35.0 5 51.0 50.0 22 60.0 59.0 19 36.0 .34.0 6 51.0 50.0 23 60.0 20 36.0 34.0 7 51.0 24 60.0 59.0 21 36.0 34.5 8 51.0 25 59.0 22 37.0 35.0 9 51.0 50.0 26 60.0 59.0 23 38.0 35.0 10 52.0 51.0 27 60.0 24 38.0 36.0 11 54.0 52.0 28 60.0 58.0 25 37.0 36.0 12 54.0 29 58.0 26 37.0 36.0 13 54.0 52.0 30 58.0 27 37.0 36.0 14 54.0 31 58.0 28 38.0 .36.0 15 54.0 Aug 1 60.0 58.0 29 38.0 36.0 16 54.0 2 59.0 57.0 30 38.0 37.0 17 54.0 3 56.0 May 1 38.1 36.3 18 54.0 4 60.0 56.0 2 39.0 36.0 19 54.0 5 59.0 58.0 3 40.0 38.0 20 55.0 6 59.0 4 38.0 21 56.0 55.0 7 59.0 5 38.0 22 55.0 54.0 8 59.0 6 39.0 37.0 23 54.0 53.0 9 out'of order 7 38.0 36.2 24 55.0 53.0 10 out of order 8 38.3 37.0 25 55.0 11 out of order 9 38.8 38.0 26 59.0 55.0 12 out of order 10 38.0 27 59.0 57.0 13 out of order 11 38.0 28 60.0 58.0 14 out of order 12 38.0 29 60.0 58.0 15 out of order 13 38.0 30 58.0 57.0 16 out ,of order 14 38.0 Ju1 1 58.0 57.0 17 out of order 15 38.0 2 58.0 56.0 18 out of order 16 38.0 3 59.0 56.0 19 out of order 17 39.0 4 60.0 59.0 20 out of order 18 39.0 5 59.0 21 ou~of order 19 39.0 6 62.0 59.0 22 58.0 20 39.5 7 62.0 23 58.0 57.0 21 40.0 8 64.0 62.0 24 57.0 56.0-22 40.0 9 66.0 63.0 25 56.0 23 41.0 40.0 10 69.0 66.0 26 56.0 24 41.0 11 68.0 27 56.0 53.0 25 41.0 12 68.0 64.0 28 53.0 52.0 26 41.0 13 64.0 61.0 29 53.0 52.0 27 43.0 41.0 14 61.0 59.0 30 52.0 28 45.0 43.0 19 / The highest,lowest and mean values of limnological data collected from the Susitna Riyer and east side tributaries downstream of the Parks Highway Bridge are presented in Table 12. A more detailed analysis can be made by referring to Figures 4 through 11,which represent the six limnological characterisitcs measured in the Susitna River and seven east side tributaries. Hydrogen ion concentration in the tributaries exhibited a tendency to rise during the swmner (Figures 4 through 11).A similar rise is also evident in the hydrogen ion data collected from the Susitna River at the Parks High- way Bridge. Total alkalinity,represented in Figures 4 through 11,exhibited an overall rise throughout the swmner months;except in the Kashwitna River, which demonstrates a less distinct increase.The highs and lows varied depending upon the tributary (Table 12),although the maximwn limits in all cases were no greater than 86 mg/l Cac03'It appears the lower Susitna River has a greater total alkalinity than its tributaries. Hardness,(Figures 4 through 11)shows a decrease from the end of March to the middle of May.For example,it dropped from 85 mg/1 Cac03 to 17 mg/l CaC0 3 at Caswell Creek.This drop,in all seven lower Susitna River tributaries,appears to have occurred just as the waters began to warm sig- nificantly.As swmner progressed,it appears the hardness of these waters remained relatively low and stable.The relative stability reflected in Susitna River tributarial waters during the months of July and August is evident in information presented in Figure 4.These comparisons demonstrate a constant 51 mg/l Cac03 through July and August,whereas the relative stability of tributarial waters ranges between 17 and 34 mg/l Cac03.It would appear the tributarial waters have a consistently lesser degree of hardness than the Susitna River waters with the same relatively low swmner- time constancy.Tributaries exhibited high late winter hardness levels. Conductivity measurements for the seven east side lower Susitna tribu- taries (Figures 4 through 11)all reflect a similar decrease from late winter to early swmner with 28 rnmlos/crn reflecting the average low and 107 umhos/crn reflecting the average high.Once the minimum specific con- ductance is reached from the middle of May to the middle of June,a general rise in conductance is observed during the swmner months.Samples collected on June 27,reflect an abnormally high increase in specific conductance, which may be attributed to extreme heavy rains prior to or during sample collection.The Susitna River displays a substantially higher specific conductance than that of the seven east side tributaries and a general increase from early June through August. There appears to be no consistent trend in turbidity in all seven east side Susitna River tributaries under investigation.Both the Kashwitna River and Ca9Well Creek demonstrated an increase in turbidity from mid-April to mid-August.This increase was significantly greater in the Kashwitna River because of its glacial origin.However,there was a high degree of fluctua- tion in turbidity in both streams.A similar fluctuation was demonstrated in the remaining five tributaries,i.e.,Montana,Goose,Sheep,Little Willow and Willow creeks (Figures 4 through 11).This high variability in turbidity can, in all likelillood,be attributed to precipitation. 20 - ,-..I-....,....-1-I .TAIlI.E12.Hithest,LowestandIleanValuesofLimnologicalDataCollectedFromThoSusitnaRiverandSevenTributariesoftheSusitnaRiver.Time"interTotnlrerio<lTCr.lporllturoContluctIvltyTurbidityAHnlinltyIInrtlne$$Collected(e)(~mhos/cm)(Jnl)pH(1ll&/I-CaC03)(noS/I.CoiC03)Tribuury1975IlighLow~le3nHighLowHcanlIighLowIleanHighLow~feanHighLowMean!!is.h1.0\0').!eanSusitnaRiveratParksHigh~3YBridge3/26-8/1813.00.08.22107412618535lOS8.S7.S7.9103344812051105~IontanaCreek3/26-8/1814.50.08.2lOS2748270.34.97.56.77.2681731511725GooseCreek4/4-8/1812.00.07.3772743640.39.47.7 6.7 7.1681734341724SheepCreek4/4-8/1814.00.07.7803046311.04.37.66.67.1681737Sl1731NI-'CaswellCreek5/14•8/1816.50.010.61753062281.05.17.66.67.2681742861736hshwltnaRiver4/24-8/1813.06.58.97737531102.0387.66.97.351173g681737LittleWillowCreek4/24-8/1814.00.06.8732041151.22.87.S6.67.0861738Sl1727WillowCreek3/26•0/1814.00.06.7J602673200.53.67.76.67.2Sl1739601737Hote:Thisdatawascollecteobiweeklyfromeachofthetributariesduringthetimeframeindicated.Thisisgeneralinformationonly,amoredetailedanalysiscanbemadebyreferringtoFigures4through11. Turbidity in the Susitna River was relatively low at 5S Jackson turbidity tmits during May and Jtme (figure 4).On JUly 7 a substantial rise to 170 J.T.U.was measured and a peak of 185 J.T.U.was reached on August 18,1975. The maxirrn.mJ.reading for east side tributaries below the Parks Highway Bridge was 110 J.T.U.in the Kashwitna River on August 18,1975. Data collected by the U.S.Geological Survey on three Susitna River east side tributaries provides a limited means with which to compare data collected in this study between March and September,1975,(Table 13). With respect to Montana Creek,the available figures would tend to support temperature,pH,hardness and specific conductance as detennined in the field during the summer of 1975.Sheep Creek figures cannot be compared due to the time frame in which the one set of data was collected.With re- spect to Caswell Creek,temperature and specific conductance are the only parameters which fall closely within the range of U.S.Geological Survey data.Hardness and pH are significantly different from more recently collected data. The base camp was relocated from the Deshka River upstream to Gold Creek on August 6,1975 to collect limnological data on the Susitna River and tributaries closer to the proposed dam site. Data collected at four tributaries,i.e.,Fourth of July,Gold,and Portage creeks,and Indian River,are shown in Table 16.Because only a single sample was collected,no trends are observable.One tributary,Gold Creek,does differ from the remaining tributaries,however,in that it re- flected a significantly higher pH,total alkalinity,and hardness.No fish popUlations were fotmd in Gold Creek other than a few grayling,at the mouth. A probable reason for the absence of fish is a placer gold mining operation approximately 6.5 miles up the Gold Creek Canyon.Findings for Fourth of July Creek,Indian River,and Portage Creek are within the range of para- meters investigated on the lower portion of the Susitna River tributaries. Chemical and physi.cal parameters collected at two locations along the Susitna River at Portage Creek and Gold Creek are presented in Tables 17 and 18.All data were collected on four different days and will be valuable for future comparative analysis.Hardness and total alkalinity may be con- sistent within specified limits at both Gold Creek and Portage Creek. Conductivity,in many previous cases,tended to increase over the spring and summer months;although later winter-early spring findings have demon- stated an tmusually high specific conductance.This same apparent trend appears true for the Susitna River at Stmshine,although data is limited. The freshwater sloughs adjacent to the Susitna River,as identified by Barrett (1974)and Friese (1975)between Talkeetna and Portage Creek are important salmonid habitat.These sloughs are used for both spawning and rearing and could be greatly affected by changes in the flow regime. Table 19 is a compilation of field investigations reflecting the l:iJIm.o- logical data collected on sloughs 8 through 21,along the Susitna River from August 7 through 14.In all cases,except slough 12,there were fish fry 22 J1TABLE13.ACompilotionofU.S.GeologicalSurveyLimnologicalDataofSpecificConcern,CollectedFromSusitnaRiverTributario$,SuspendedDissolvedDissolvedWaterSpecificSedimentOrtho-I\itnteGNameofTempcnturoConductanceDischargeSuspendedDisch"rCoNitroteHardnessPhosphateNitr.iteTributoryDoto(C)(urMos/cm)CcCs)SediJ1lent(Tons/Doy)r.!!(mfl/l-N03)(mg/I-CoC03)(mg/l-P)(mg/l.:;02G/;03)--~lontonaCreek7/1/717.0242,28020S1,2608/9/719.S243,5001831.7S09/17/718.543376220.7.21.00IS8/11/72 16.547182--7.4-17.00.OSIVw9/26/724.S37606- -6.3-13.11.03SheepCreek3/4/72-63---7.50.3625CaslIeliCreek9/8/72.13.S5423- -6.8.-20.05.009/26/724.05131--7.2-19.02.00 1ab1e 14.Water Quality Analysis'of Samples by the U.S.Geological Survey 'Central Laboratory in Salt Lake City ~Utah.Collected Harch 25 ~ 1975 from the Susitna River at Sunshine. Alk ...Tot (as CaC03)mg/l 71 ~02+N03 as N Diss mg/l 0.21 Bicarbonate mg/l 86 Phos Ortho Dis as P mg/l 0.04 Calcium Diss mg/l 29 Phosphate Dis Ortho mg/l 0.12 Chloride Diss .myl 21 .Potassium Diss og/1 2.1 Color 0 Residur Dis Cae 1 Sum mg/l 137 Conductivi t.Y.242 Residue Dis Ton/Aft 0.19 Fl uoricle IH?s mg/l 0.2 Residue Dis l8De mg/1 141 Hardness Noncarb mg/1 20 Sar .0.5 Hardness Total .mg/1 91 Silica~Dissolved mg/l 9.2 Iron Dissolved ug/l 10 Sodium Diss myl 11 Magnesium Diss ..mg/l 4.5 .Sodium Percent ..20 ~~nganese Dissolved ug/i 0 Sulfate Diss mg/l 17 -_. Nitrogen NHf as N tot mg/l :Nitrogen TotOrg N mg/l 0.180.05 Nitrogen Tot as N mg/l 0.42 Nitrogen Tot KJD as N mg/l 0.23 .Nitrogen Tot as ~03 mg/l 1.9 N02+N03 as N Tot mg/l 0.19 Phosphorus Tot as .P ,mg/l 0.01 .'Cations Anions mg/l ineq/l ""!DgJ1 meqil.~.... :Calcium Diss "29 '1;448 Bicarbonate 86 .1.410 Magnesium Diss 4.5 0.371 Chloride Oiss 21 0.593 PotassiuJil Diss .2.1-0".054 Fluoride Diss 0.2 0.011 Sodiutl Diss 11 0.479 Sulfate Diss .17'0.345 ~02+N03 as N D -0.21 0.015 Total 2.34~·Total .2.381 .IlIlIiJt1. Table'15.Compiled Data of Interest Collected by U.~.Geological Survey from.the Susitna River at Sunshine... -."'Specific Suspended Conductance Sediment Date Pl!.(umhos/ern)(mg/l). .~~ 7/2/71 7.5 138 .1 ..040 7/2/71 7.5 131 1~140 8/11/71 9.0 170 3.)510 24 Figure 4.Limnological Data Collected from the Susitna River at the Parks Highway Bridge,March 26 to August 18, Devil's Canyon Project.1975. 0 16.0 9.0 0 I w 12.0c::8.0::J I-<c::w 8.0 ~1.0a. ::::E 11.1 t- o:4.0 6.0 11.1 I- ~0.0 5.0 25 "Figure 4.(Cant.) 220 LimnologicaJ Data Collected from the Susitna River at the Parks Highway Bridge.March 26 to August 18. Deyil's Canyon Project.1975. 180 ..... U ::I "0 Cou 210 200 190 180 1]0 160 150 140 130 120 110 100 90 80 70 170 - 160 150 140 120 110 loa 90 80 70 60 50 40 30 I . ?/26 26 Fig.5.Limnological Data Collected froIT!Montana Creek at the High\'Iay Bridge,March 26 to August 18,Devil's Canyon Project,1975. 9.0 8.0 4./30'5/2.7 6 7 7.21 6//8 5/14 ell I 7/7 8/4 DATE-J975 3/26 6. ~7.0 ,3/26 4/30 em"6/271'2'11/16 " ' .',6/11 7/7 8/4 DATE-1975 uo I ~16'.0 :::> ~12.0 a:w ~8. w 1-'4.0 a:w ~O. ;: tt') 0u f() <t 0 ,u u CJ)<«u ...J en .......« (!)...J~....... I 5 C!)->-~l-I ,·Z CI) 20 ...J en /'-'" l.LJ <t:Z:x=10 0 10...J a:«3/28 4/30 5/27 6/27 7/21 8/1S «3/28 6 27 M4 6/11 7/7 8/4 ::r:6/11 7/7 ...J DATE-1975 DATE-1975 ~ 0.r- -27 Fig.s.(Cont).Linmological Data Collected from ~lontana Creek at the Highh'ay Bridge,March 26 to August 18,Dcvil's Canyon Project,]975. 10 .....', roo ::5 u 90 .......en ::>0 80::I:...._c ::E J J::(70 >- J ....>-C....60>m 0::::....50 ::>u f- ::>c . z 40 0u 30 ... DATE-1975 - 4/30 5/zr s/zr 7/2.'e/18 ~1r4 .6/11 7/7 8/4 DATE--1975 28 -'" Fig.6.Limnological Data Collected from Sheep Creek at ~he Bridge, f'.larch 4 Through August 18 ,.Devil J s Canyon Project,1975. c.>o I ~16.0 ::J ~12.0 0:: l1J ~8.0 w .I-4. 0: W~0.0 3: 4/4 e/zr 8/zr '1/2'8/184/3~6/11 7n 8/4 DATE-/975 9.0 8.0 :::I:7. Co 6.0 4/4 S/f4 8/1'7/7 6/4 4/30 r¥27 6/27 7/21 e/18 DATE-1975 tc') 0 \.0 <t rt')-0 0en90c.>50<t <tc.> ...J 70 en 40.......<t(!)yIV!~...J I 50 -.~30.>-:::E .\l-I-30 enz 20-en ..._~.-...J W-<t Z ~10 I I £:)10 I...J 4/4 1l/14 6/11 7/7 e/4 0::4/4 5/14 6/11 7/7·8/4-<t .4/30 1l/27 6/Z7 7/21 e/18 <t 4/30 11/27 6/27 7/21 e/18 ...J .DATE-1975 :::I:DATE-J975.~ 0r-- -29 Fig.6.(~ont).Linmological Data Collected from Sheep Creek at the Bridge,March 4 Through August 18,Devil's Canyon Project,1975. .... - - - 4/4 II 14 7/7 8/4 .4/30 5/27 6/27 7/21 .8/IS DATE-1975 ~:::>-,u 80 I-10 "J en I 0 70 r:c I-~Q~6 - I mr0::5 I-:::> >50 l- I- (.)40 ~::::> 0z 0 30 (.)4/4 !5/H 6/11 7/7 8/4 4/30 !5/27 6/2.7 7/21 8/18 DATE-1975 ..' 30 Fig.7.Limno1ogica1 Dat;a Collected from'Goose Creek at the Bridge, March 4 Through August 18,Devil's Canyon Project,1975.' (,) 0.16.0- w 0::: ::::>12.0 tia:w 8. 0.. ~ ,W 4.0 t- a:w O.O..J--~-r--;---r---r--r--r--r-..,...--.---t;4/4 8/27 6/27 7/21 8/18 __8/11 7/7 8/4 ;:DATE-1975 &> (,) 4:( (,) ~90 ....J ~70 ,:E .•>-50.t- z -I 30« ~ ....J 10-4---r-.--rI--'Ir--jr--rj"""'Tj--..--.,---,....-«4/4 8/14 8/11 7/7 8/4 4/30 8/27 8/27 7/2'8/18 ~DATE-1975 .0.- 31 9.0 8.0 :::I:7.0 a. 6.0 DATE-1975 4/4 a/14 6/11 7/7.8/4 4/30 8/27 6/27 7/2'8/18 DATE-1975 -, Fig.7.(Cont).Lirnnological Data Collected from Goose Creek at the Bridge,~larch 4 Through August 18,Devil's Canyon Project,1975. DATE-1975 - .,. 50 ::::>10.... J I>-.... o ~5 :::>.... -4/4 e/l4 6/11 7/7 6/4 4/30 ~6/27 7/21 e/18 ~80 u ~70o:z: ::!:60 T- ~5 > ....4u :::> ~30 o u 20--r--.-~.,..--..,.-....--....--....--....--....-- ~.5 4/30 OJ/27 6/27 7/21 8/le ti/14 6/11 7/7 8/9 DATE-/975· 32 Fig.8.Limnological Data Collected from Cas\vell Creek at the Bridge, t-Iarch 26 Through August 18,Devil's Canyon Project,1975. () 0 16.0,w 0: :J 12.0 ti 0:::8.0wa.. ..;.0..::i!:w 4. I- 0::O.w ti~ fJ/zr IS/V 7:21 8/18 6/11 7/1 8/4 DATE-1975 :I: 0. 9.0 8/18 DATE-1975 I i 5/14 6/11 7/7 8/4 5/21 6/27 7/21 B/19 DATE-1975 10 3/28 90 tt)80 ou«70u en <t 60 ..-1...... (!)50 :i:, ~40 wzo 30 0:: <t :c 20 5/14 6/11 7/7 8/4 lS/Z1 6/27 7/21 8/18 DATE-1975 "!I/2S - t()ou«u en <t -l (?> ::;E 40, ..>- I- Z -l <J:2 ~ -l <J: -I .~ o I- 33 Fig.8.(Cont).Limnological Data ColI ected from Cas\~ell Creek at theBridge,March 26 Tnrough August 18,Devil's Canyon Project,1975. 180- 170 160 150 140 10 :::E 130u ::>"-I-en 0 120 -:> I:t:>-~I-5~110I Cl >-[D r-roo 0:::>>r- I- 900 :::::>. Clz 800u 70 6 50 .40 3 I •I , 3/26 .15/14 6/11 7/7 8/4 5/27 6/27 7/21 8/la DATE-/975 5/14 6Ilt 7/7 8/4 5/27 6/27 7/21 e/18 DATE-1975 .- - - - - ... 34 - Fig.9.Lirnnological Data Collected from the Kashldtna River at the Bridge, ApriJ 24.1nrough August 18,Devil's Canyon Project,1975. (.)o I W 0::16.0:::> ~a:12. wn.~8.0 w 'I-4.0 o 9. 8.0 =[7.0 6.0 5/27 6/21 7/21 8/19 6/11 7/7 8/4 5.()-I"-;r--Y-.,--r-...,--r--,,..-r--~......-- 4/24 !ill 4 8/11 7/7 8/4 4/ao fS/27 8/ZT 7/21 e/ls DATE-1975 DATE-I975 Iii i .1 I \ 4/24 ~/14 6/11 7/7 8/4 4/30 em 6/27 7/21 8/18 DATE-1975 rt) 0u« (J rn <C rt)70.-J .......0 (!)7 u 60::«uI.>-rn 50I-50 <C --Z -J.--.......-J :3 (!)40 <C ~~I-J 10 •rn 3«4/24 5/14 6/11 7/7 8/"rn 4fro e/21 e/27 7/21 8/18 W-J Z 20~DATE-J975 Cl 0::0 <Ci-:r 10 35 Fig.9.(Cant)._LinmologicaL Data Collected from the Kashl'l'itna River at the Bridge;April 24 Through August 18,Devil's Canyon Project,197S. 100 ~80 50()......en 700:c ::::>~ ~60 r- I J >-I r-50 >-t->0r-4 CD0 ::::>n: 0 ::::> z 30 t- O 4/2.4.~/14 ,6/11 7/7 8/4 10()4/30 ~/2.7 6/27 7/2/8/18 DATE-1975 5 I 4/30 !!I/27 6/27 1/2/e/18 e/l4 6(11 717 8/4 bATE-'1915 36 ..' _. Fig.10.Limnological Data Collected from Little WillOl';Creek at the Bridge,April 24 Through August 18,Devi1's Canyon Project,1975. (,) 0 I Wa:::16.0 9.0 :::> ~8.0a:::12. wa.:I:::!:0.7.0 w I-4."S.O 0:: W 5.0I-0.0 J I I I I I ,I<4/24 M4 6/11 7/1 8/4 4/24 1l/14 tI/1I 7/7 8/4:=4/3!J t5/27 6/27 7/21 8/18 4/30 Ilm 6/27 7/21 8/18 -OATE-1975 DATE-1975 rt)-0 U oct U 1'1)" C/)0 <::u« "-.oJ 90 u ......(/)50 (!)<C::::10 -140I >-..... (!) I-~30z50 .J C/) (/) <C 30 W20~z -.oJ 0 <C 10 a:::10I<C-I 4/24 8/14 e/ll 7/7 8/4 :z:4/24 5/14 6/11 7/7 8/4 <C 4/30 6/27 6/27 7/21 8/18 4/30 5/2.7 6/27 7/21 e/18 I-DATE-1975 DATE-19750r- .. 37 Fig.10.(Cant).Limnological Data Collected from Little Willow Creck at the Bridge,April 24 Through August 18.Devills Canyon PToject,197S.' ~~()........ ~70 :E ::;) ::(60 l- I "":) >-I f-50 >- >f- f-0 ()40 ED ::;)c: 0 :::>z 30 f-a () 20-L-'lr-"-.Jf---.-r---r--r-....................-- 4/24 ~/14 S/Il 7/7 80M 4/30 Mo7 S/2T 7/21 a/18 DATE.-1975 10 5 I .4/30 5/2T 6/27 T/2(e/ls &'14 8/11 7/7 8/4 DATE-1975 38 - Fig.11.Limnological Data Collected from WillO\~Creek at the Bridge. r.larch ·26 Through August 18,Devil's Canyon Project,1975. 3/28 8.0 5.O~..,---.-r-.---r--.I--C-,r-r--r-.,. 4/30 e/Z7 e/27 7 21 a/18 e/14 6/11 7/7 8/4 DATE-1975 6.0 9.0 ~7.0 e/27 6/27 7/2\8/18 6/11 7/7 8/4 .DATE-1975 {)o Iw 16.0 0: :::>!;:t 12.0 c:::wa.8.0 :: ~wl-4.0 0:w O.O,...L.--t-::r===h-.-.-r--r--r--......,r- ~a/28 3: - 4/30 &1'27 6)27 7/21 8/18 5/14 13/11 7/7 8/4 DATE-1975· ro 0 0 <t ....0 en«ro ...J90 o 60-0......~(!)0::=70 50 I .en>-« -1-5 ..J 40z...... :J (!) <t30 ~30~ ..J en <t enw 20 ..J !/l1S 4/30 e/27 em 7/21 B/l8 Z <t e/I..6/11 7/7 8/4 CrDATE-1975 0::100«a/21S~.:I: -.. 39. Fig.11.(Cant).Limnological Data Collected from ~';i110\"Creek at the BridgeJ.March 26 Through August IS,Devil's Canyon Project,1975. - 10 -5 5 ::> I- J I >-".' ..... 0 CD 0: ::J t-, / I I ( I I t e/27 5/Z7 7/2 r a/18 6/11.7/7 a/~ .DATE-1975 160 150 140 130 120 ~u 110.....en 0 :I:100~ J I 90>-l- S; ~80 (.) :J '0 70z 0u 6 50 40 30 20 !I I I I "$/2Ji 4/30 e/14 -1 .......--:-,---:-,---r---,.---,.--.---T'""""",,"",-.-- 4/30 e/27 6/27 7/21 aIrs 5/+-5/11 7/,..a/40 . DATE,..1975 - ". 40 Table 16.Limnological Data Collected from Four Tributaries of the 5usitna River. Tributary Fourth of Gold Indian Type of Data JUly Creek Creek River ,.."l\<o;r Date (1975)8/9 8/13 8/19 Time 4:13 p.m.6:00 p.c.11 :50 a.m. Depth range (feet)1-3 .5-3 1-4 Water temperature (C)14.0 12.0 9.0 pH 7.5 8.1 7.5 Total alkalinity (mg/l as CaC03)34 120 34 Hardness (mg/l as CaC03)17 160 34 Dissolved oxygen (mg/l as 02)9 11 11 Portage Creek 8/10 5:00 p.m. .5-4 9.0 7.5 51 34 11 .Table 17.Limnological Data Collected from the Susitna River I:;unediately Above Gold Creek,August 1975.- Type of Data Water temperature (C) pH . Total alkalinity (mg/l as CaC0 3) Hardness (mg/l as Ca003) Dissolved oxygen (mg/l as 02) Orthophosphate (mg/l as P) Nitrate (mg/l as N) .Nitrate (mg/l as N) Turbidity (FTU) Specific conductance (unhos/cm) 8/13 6:00 p.m. 14.0 8.0 86.0 .94.0- 11.0 70.0 165.0 8/18 3:00 IZ.m. 12.0 8.0 86.0 110.0 10.0 0.04 >0.01 >0.10 Table 18.Limnological Data Collected from the Susitna River I~ediately Above Portage Creek, August 1975. ....8/12 8/18 ~Type of Data 1:10 p.m.3:00 p.in. Water temperature (C)13.0 11.0 pH 8.0 8.0 Total alkaliniLy (mg/l as CaC0 3)68.0 .94.0 Hardness (mg/l as CaCO_)68.0 103.0 Dissolved oxygen (mg/!~as O2)13.0 11.0 Orthophosphate (mg/l as P)0.05 0.05-Nitrite (mg/l as N)0.01 0.02 Nitrate (mg/l as N)0.5 0.3 Turbidity (FTIi)85.0 190.0 -'. - --. 41 TABLE19.LimnologicalDataCollectedFromFifteenSloughsAlongTheSusitnaRiverBetweenTalkeetnaAndPortageCrecK...TotalDissolvedSloughDateDepthTemp.BottomAlkalinityHardnessOxygenNumber1975Time(feet)(C)Type·pit(mg/1-CaC03)(rng/1-CaC03)(mgl1-b2)------.......8a8/92:50pm-'13.5S,Sa,G,C7.58668898/91:16pm0.858.0S,Sa,G,C.7.05168. 7lOa8/7--9.5H,S,G7.06868lOb8/7--10.0H,S,G,C7.586100118/7-2.308.5Sa,G,C7.510312010128/7,.-5.5~I,S,G,C7.51371208~l'V138/134:25pm0.666.5Sa,G7.5lq31009148/7,1,469.0S,Sn,G,C7.06851-158/812:0Spm1.6313.5S,Sa,r.7.051349168/81:26pm0.507.0S,G,C6.551347.'.178/149:00am0.834.5S,G,C7.051518188/149:40am0.758.0.H,S,Sa7.568689198/1011:25am2.949.5S;Sa,G,C7.586688208/10If:13pm-9.5S,Sa,G,C8.068518218/101:33pm-10.0S,Sa,G,C,B7.5103868*H-Muck,S-Silt,Sa-Sand,G -Gravel,C -Cobble,D -Boulderl c,"f---II-~TABLE20.LimnologicalDataCollectedfromtheImpoundmentAreaoftheSusitnaRiverNearJay,Watana,andDeadmanCreeks,Devil'sCanyonProject,April24,1975.JayCreekWatanaCreekDeadmanCreekTypeofData(100Yds.Downstream)(3Mi.Upstream)(100Yds.Downstream)DepthSurfaceSurfaceSurfaceWaterTemperature(C)0.00.00.0pH8.07.57.5TotalAlkalinity(mg/lasCaC03)102.6102.651.3Hardness(mg/lasCaC03)119.7136.868.4DissolvedOxygen13.013.a13.0lIloTurbidity(JTU)w0.50.50.4Conductivity(Alllhos/cm)280255220 present,including grayling,burbot,rainbow trout,whitefish,coho,and chinook salmon. Except for slough 12,total alkalinity measurements ranged from 51 mg/l to 103 mg/l caC03.Harclness values ranged from 34 mg/l to 120 mg/l caC0 3 • Dissolved oxygen measurements ranged from 7 to 10 p.p.m. Table 20 shows the results reveal no alarming readings and are charac- teristic of undisturbed Alaska rivers. The section of the Susitna River between Devil Canyon and Talkeetna will be most adversely affected by flow regulation of a hydroelectric dam. This section of river has not had a systematic limnological study conducted on a year-round basis.An expanded linmological study is necessary to fully understand the present characterisitcs of the Susitna River. CONCLUSION The Alaska Department of Fish and Game has not conducted studies of limnological characteristics or indigenous fish stocks of the mainstem Susitna River prior to 1974.Therefore,comparative data are either minimal or non-existent. This fisheries study documented anadromous and resident fish fry utilizing the Susitna River for rearing during the winter when the water is silt free. It appears the majority of salmonids migrate to freshwater tributaries and other periphery areas of the Susitna River when the silt loads increase dur- ing the sunnner.This undefined migration warrants additional study which should attempt to define species composition of the Susitna River on a seasonal basis.The section of river which will be most affected is directly downstream of the proposed Devil Canyon Dam site.A limited amount of sampling of resident fish stocks in this area revealed popUlations of grayling in all tributaries except Gold Creek.The timing in which these grayling and other resident fish utilize the Susitna River is not known,and should be documented. The limnological aspect of this study contains important baseline data that should be continued and expanded in order to document changes in water chemistry following iriIpoundment.It has become apparent during this study that one of the more critical areas which require additional research is definition of flows.Minimum seasonal flows should be established through regulation to i~sure access in and out of sloughs for fish. ACKNOWLEDGEMENTS The author wishes to acknOWledge the assistance of Jeffrey D.Hock, temporary Fishery Biologist,the U.S.Geological Survey,Water Resources Division,for their advice and use of their laboratory,and the IJ.S.Fish and Wildlife Service for funding. 44 ..... - ...' - - .... POTFNIIAL IMPACTS Following is a list of impacts the Fisheries Divisions of the Alaska Department of Fish &Game has compiled.This is not necessarily a complete list,as other impacts may become apparent during the course of the study . Environmental impacts will occur both up and downstream from the dams.Two phases of development of the hydroelectric facilities will occur:(1)the construction period projected to extend over a l2-year period,and (2)the operation of the facility.Environmental impacts of this project will be (1)those occurring during the construction period,and (2)those occurring during the post-construction period which constitutes the entire life of the project. Construction Period Impacts Construction of the dams will necessitate the diversion of the Susitna River from its natural course.The major effect during this period is ex- pected to be an increase in silt load due to construction activities.This decrease in water qualify may cause the following impacts: 1.Disorientation of adult salmon returning to their horne streams may result in a decrease of fish production in the upper areas of the river. 2.Change in substrate composition in sloughs resulting in decreased spawning and rearing area.Chtnn and sockeye salmon are known to utilize these areas for spawning. 3.Lack of clearwater conditions during fall and winter months limiting fry from utilizing the mainstem Susitna River for rearing. 4.Degradation of water quality resulting in possible alterations in the aquatic food chain.Some orders of insects,important food i terns for salmon fry,may be unable to adapt to the changed water quality. 5.Reduced flows associated with filling of the reservoir may reduce downstream spawning habitat and could alter fish distribution below dam.During the low flow construction period a substantial risk of water pollution from concrete pouring,oil spillage,etc.will be present. 6.Reduction in run of salmon could follow reduction of flow (Penn,1975). Reducing flows could result in reduced access for salmon utilizing the upper stream areas. Post-Construction Impacts 1.Turbidity -The Susitna River currently carries a heavy load of glacial silt in spring and surrnner.The river's water is clear during fall and winter months.Impoundment will result in increased turbidity and silt loads year-round.Also,turbidity may be increased if there is pennafrost in the area (Afton,1975).This condition may cons tribute to: a.Inability of fry to utilize the rnainstem for rearing. 45 d. f. b.Decreased summer turbidity allows greater light penetration which would encourage more primary production.Rate of zooplankton development may not necessarily be increased due to possible lower temperature in April-May period.Rearing salmon depend on zooplankton stock at this time. c.Influence of bedrock on impotmdment water quality may affect fisheries (Duthie and Ostrofsky,1975). d.Increased mortality due to decreased summer turbidity resulting in higher predation success. e.Decreased spring and summer turbidity would likely limit downstream migration to the darker hours,thereby extending the downstream migration periods further than at present since some migration occurs in the turbid waters during daylight.There is evidence suggesting that increased time to migrate increases yotmg salmon mortality (Geen,1975). 2.Temperature -Normal temperature regimes will be altered by impotmdment. Various effects may be seen.These include,but are not limited to: a.Any change in downstream fall temperatures could affect spawning success of salmon.There is evidence that relatively high tem- peratures are associated with poor returning Ytms (Geen,1975). b.Changes in the incubation period of salmon eggs and incubation condi tions . c.Premature fry emergence and seaward migration due to increased rate of development could result in increased mortality because the migration may occur prior to the warming of estuaries and the development of estuarine zooplankton populations. Alteration of the normal thermal regime would change the overall productivity of the river,which could add extreme stress to fry populations. e.Summer temperature decrease could affect upstream migrational time for adult salmon. Changes in the aquatic food chain,due to the inability of some organisms to adapt to even slight thermal alterations. 3.Chemical and Physical Parameters. a.Supersaturation of nitrogen and oxygen depletion resulting from stratification and spillage are possible,impacting down- stream fishes for an tmknown distance. b.Increases in dissolved nitrogen gas can also be due to air vented into turbines to reduce negative pressures during weekend periods of sustained low generating levels (Ruggles and Watt,1975). 46 ... - c.Dams slow water transport which gives more time for the biochemical oxygen demand to consume available oxygen,thus re- ducing dissolved oxygen content.Dissolved oxygen levels will probably be altered due to changes in river conditions.Low levels could preclude the suvival of fish in downstream slough areas. d.Conductivity,alkalinity,and pH can increase after impouncbnent construction (Geen,1975). 4.Organic Debris a.Debris has a time frame of 100-200 years,reduced with time, resulting from forest drowning. 5.Flows a.Altered lake levels may result in flooding,slumping,erosion,and general shoreline degradation.Littoral zone changes affect fisheries. b.Changed ice regimes can also affect river and lake shorelines. A change in water quality can be expected due to erosion and sediment processes from altered water levels,flows and ice regimes,(Dickson,1975). c.Changes in substrate composition of spawning areas due to lack of natural scouring;this would also affect winter survival of eggs. d.Decreases in water levels during June and July will affect adult access to spawning areas. e.Reduced discharge during summer could alter upstream migration of salmon. f.Reduction of flow could affect survival of young salmonids moving to saline water during April-May.Seaward migration is directly related to river velocity and therefore could extend this period, (Geen,1975). g.Reduction of nonnal spring and summer flows could result in a decrease of fry rearing habitat and could leave out-migrating smolts stranded. RECCMvtENDATIONS Before the full effects of this project on fish and wildlife are identi- fied,considerable studies are necessary which will be both long term and costly.Following is a brief resume of biological studies and investigational goals required prior to final definition of impacts resulting from impouncbnent of the Susitna River at Devil Canyon and Watana. I 47 U.S.G.S.,and other appropriate agencies.The following is a partial list of necessary information: 1.Current unregulated flows and projected regulated flows. 2.Temperature regimes. 3.Turbidity and sediment data. 4.Anticipated physical changes to the natural locations,on a seasonal basis.... II A cO&irehensive fishery study to address adult and juvenile sallnonid abun ance,distribution,migrational patterns,and age composition by species for areas both upstream and downstream of the proposed Devil Canyon Dam. The Cook Inlet fishery is of mixed stock and presents many problems for its proper management.Total escapement data by species is not avail- able for the Susitna River drainage.Until total escapement into the drainage is determined the value of the sallnon stocks in the upper Susitna River cannot be evaluated.Spawning ground surveys demonstrate the importance of this area to chum and pink sallnon. - Data collected since JUly 1974 provides baseline information only. Generalizations may be made,but sufficient information is not avail- able to detennine full impacts of dam construction and operation upon the fishery.Intense investigational projects should be initiated in the study area to provide pre-construction data to adequately evaluate possible impacts. III A study of affected habitat areas will be conducted in conjunction with the fisheries program.Productivity and limiting factors can be de- fined by a thorough lirrmological study.Physical,chemical,and biological conditions of the Susitna River and other affected areas should be examined.Specific concerns are: 1.Changes in quality and quantity of spawning habitat both upstream and downstream of the proposed dam sites as a result of (a)flow and releases,(b)innundation of upstream areas and (c)effects of periodic pool fill and drawdown. 2.Effects upon the habitat and fisheries resource directly as a result of construction activities. 3.Effects of increased human use resulting from improved air and road access upon both the Susitna River drainage and adjacent fisheries. 4.Environmental assessment of transmission line system to determine effects of stream crossings upon resident and anadromous fish populations and habitat during both construction and subsequent operational IT~intenance. For further information on biological study proposals refer to the package presented to U.S.Fish and Wildlife Service and U.S.Anny Corps of Engineers on November 18,1975. 48 - - - Atton,F.M.1975. Saskatchewan. 32:101-105. LITERATURE CITED Impact Analysis:Hindsight and Foresight in Journal of the Fisheries Research Board of Canada. Barrett,B.M.1974.An Assessment Study of the Anadromous Fish Populations in the Upper Susitna River Watershed Between Devil Canyon and the Chulitna River.Alaska Department of Fish and Game.1-56. Cantlon,J.E.1969.The Stability of Natural Populations and Their Sensitivity to Technology in Diversity and Stability of Ecological Systems.Brookhaven Symposia in Biology.22:197-206. Dickson.I.W.1975.Hydroelectric Development of the Nelson River System in Northern Manitoba.Journal of the Fisheries Research Board of Canada.32:106-116. Duthie.H.C.,and M.L.Ostrofsky.1975.Environmental Impact of the Churchill Falls (Labrador)Hydroelectric Project:A Preliminary Assessment.Journal of the Fisheries Research Board of Canada. 32:11 7-125. Friese,N.V.1975. lations of the Proposed Devi 1 Fish and Game. Pre-authorization Assessment Upper Susitna River Watershed Canyon Hydroelectric Project. 1-121. of Anadromous Fish Popu- in the Vicinity of the Alaska Department of Geen.G.H.1975.Ecological Consequences of the Proposed t·10ran Dam on The Fraser River.Journal of the Fisheries Research Board of Canada. 32:126-135. Lind,O.T.1974.Common Methods in Limnology.St.louis,C.V.Mosby Co .• 154p. McCoy,G.A.1974.Preconstruction Assessment of Biological Quality of The Chena and Little Chena River in the Vicinity of the Chena Lakes Flood Control Project Near Fairbanks,Alaska.U.S.Geological Survey Water Resources Investigations.29-74:1-84. Penn.A.F.1975.Development of James Bay:The Role of Environmental Impact Assessment in Determining the Legal Right to an Interlocutory Injunction.Journal of the Fisheries Research Board of Canada. 32:136-160. Ruggles,C.P.,and W.O.Watt.1975.Ecological Changes Due to Hydroelectric Development on the Saint John River.Journal of the Fisheries Research Board of Canada.32:161-170. Warren,C.E.1971.Biology and Water Pollution Control.Philadelphia, W.O.Saunders Co.434p. 49 Welch,P.S.1952.Limnology.New York,McGraw-Hill Book Co.538 p. Wilhm,J.L.1970.Range of Diversity Index in Benthic Macroinvertebrate Populations.Water Pollution Control Federation Journal,v.42, No.5,pt.2,p R22l-R224. APPENDIX The aerial photographs in this appendix show the sample sites (fish, linmological,and benthos)used in this study.The exact site was located under the letter which denotes the type of sample ...A,R,B,or L. There is approximately a six-mile stretch of river near the Shennan area not covered by aerial photographs.With the exception of this stretch, the river is completely covered by photographs from Devil Canyon downstream to the mouth.The scale from Gold Creek downstream is 1:63.360 and the scale upstream from Gold Creek is 1:30.000.These photographs were taken in July,1975. LEGEND A -Adult fish R -Rearing fish B -Benthos sample site L -Limnological study points W-Winter collection S -Summer collection KS-King salmon SS-Silver salmon 50 RS -Red Salmon CS -Chum salmon PS -Pink salmon RT -Rainbow trout GR -Grayling DV -Dolly Varden BU -Burbot WF -Whitefish 11JJJJ l]rJ 1]1JrJ 11l11]JJJJ 1J1JJ 1]1] 1JJ1JJ ]1] ]111)JJJ ]J 111I1JJJJJc.:k" " PRE-AUTHORIZATION ASSESSMENT OF THE SUSITNA RIVER HYDROELECTRIC PROJECTS: A LIMITED WILDLIFE STUDY GAME DIVISION SECTION BY CARL MCILROY GAllE BIOLOGIST AND TED SPRAKER GAME BIOLOGIST ALASKA DEPARTMENT OF FISH AND GAME GAME DIVISION ANCHORAGE TABLE OF CONffi\ffS INTROrucrION PROCEIlJRES RESill.TS Moose Distribution,June 1974 Moose Wintering Distribution,1974-75 Evaluation of Moose Wintering Range, Moose Condi tions,Loss of Winter Range by Inundation. Caribou Distribution and Trails Harvests and IIunting Pressure Observation of other Mammals DISCUSSION AJ~CONCLUSIONS MITIGATIVE ACTIONS REFERENCES CITED Page No. 1 1 2 2 2 3 6 6 7 7 9 11 UPPER SUSITNA RIVER WILDLIFE STUDIES by:Carl McIlroy Game Biologist III Alaska Department of Fish and Game INTRODUCTION Reconsideration of portions of the Susitna River as a source of hydroelectric power has necessitated a reevaluation of the effects of a dam or dams on the area's indigenous and transient wildlife.Former studies included an evaluation of the monetary values of the Susitna basin based strictly on estimated harvests (Anon.1954).However,the applicability of those data to the present is limited because of changing harvest patterns and changing calculations placed on an animal's worth. A detailed report on the fish and wildlife resources of the Susitna basin and the impacts of the proposed Devil Canyon and Denali dams on those resources (Anon.1960)was an excellent evaluation considering the limited information available at that time.This report is intended to supplement the 1960 study by updating inventory and harvest data,by reporting on big game distributions observed during the spring of 1974 and the winter of 1974-75,by reevaluating the main effects on wildlife caused by the proposed Devil Canyon and Watana Dams,and by suggesting mitigating actions and future studies based on the current perspective. PROCEDURES Moose distribution surveys during June,1974 were flown with a PA- 18 supercub by ADF&G biologists.The Susitna River above the proposed Devil Canyon Dam up to the Susitna Glaciers and the lower portions of its major tributaries were surveyed (Fig.1).Flight lines within the surveyed area were approximately one mile apart,representing a survey of moderate intensity.Big game distributions during the winter of 1974-75 were assessed by making five aerial surveys over the Susitna study area at roughly monthly intervals.The Susitna study area for these flights was defined as the Susitna River upstream from Gold Creek and the lower portions of the Susitna River's major tributaries (Fig.2), Observations of all larger mammals were recorded,and those observation numbers were located on a map.The upper limit of surveys was the highest elevation that moose were found.The initial flight during November was intensive,and moose sex and age composition were obtained along with big game distributions.Complete subareas were searched for moose.Because of poor weather,decreasing daylight,and increasing ratios of ferry time to count time,not all of the study area was surveyed. Subsequent flights,from January through April (Fig.3-6),were less intensive,and roughly fixed flight patterns were flown with no attempt to search all subareas for moose.The November survey was 1 flown with PA-18 aircraft,January,February,and part of March flights were made with a Cessna 185,and the remainder of March and April surveys were made with a PA-18. Moose condition evaluations were made during the April survey.A body fat condition evaluation of each moose observed was made based on a scale of (1)dead -due to natural mortality other than predation,(2) bony -poor coat,slab-sided,hips and ribs obvious,(3)moderately fat -fair coat,moderately rounded,hips and ribs not obvious,and (4) fat -good coat,rounded shape,hips and ribs well-covered.Range use evaluations during April were made to delineate areas of preferred or critical winter range that would be inundated by construction of the Devil Canyon and Watana dams.Classification of each area and boundaries for each area were determined by the relative density of cumulative moose tracks observed from early winter until April 23,1975.The classification categories were:(1)light use -occasional tracks with little cratering,(2)moderate use -tracks and cratering common but not dense,and (3)heavy use -tracks dense and cratering extensive.The square miles of each range category were determined by overlaying a mileage grid over a map showing the classified areas. Harvest data were obtained from harvest report returns.Because many hunters do not report where their animal was taken,reported harvests for specific areas are usually less than actual harvests. RESULTS Moose Distributions During June,1974. A survey of the upper Susitna River and lower portions of major tributaries was flown during June,1974 to obtain spring moose dis- tributions and to locate any areas with high densities of cows and calves (calving areas).Results of these surveys are shown on Figure 1. A high moose density was observed south of the MacLaren River,but no other areas with high moose densities were observed.Few moose were seen above 3,500 feet. Moose Wintering Distributions,1974-75. Locations of moose observed during November,January,February, March,and April surveys are shown on Figures 2 to 6,respectively.The decrease in moose numbers observed with advancing winter was partly due to less intensive survey procedures and partly due to poorer visibility of moose as they move below timberline.A comparison of these maps shows that,in most cases,moose moved from higher to lower elevations along drainages as winter progressed.For example,moose seen near the Susitna glaciers during November (Fig.2)apparently moved down to Valdez Creek by January (Fig.3),and down to Windy Creek by February (Fig.4).One possible exception to this movement pattern from high to low elevations within a drainage system was noted.The large moose concentration along the "big bend"of the Susitna River observed during 2 JJJjJJNovemberwasnotapparentduringlatersurveys.ItispossiblethatthesemoosecrossedtheSusitnaRivertojoinwinteringmoosecon-concentrationalongthe"bigbend"oftheSusitnaRiverobservedduringlatersurveys.ItispossiblethatthesemoosecrossedtheSusitnaRivertojoinwinteringmooseconcentrationsobservedalongtheOshetnaRiverandSanonaCreekduringlatewinter.Heavytrailingonandalongmajordrainageswascommonlyobserved.Trailscriss-crosseddrainageswithinmooseconcentrationareas,indicatingthatvegetationalongbothbankswasbeingutilized.MooseAbundanceandComposition.WithintheSusitnastudyareaasdefinedforthe1974-75wintersurveys,2,225moosewerecountedduringintensiveNovembersurveys.However,notallofthedrainagesweresurveyed(Fig.2).Extrapo-lationsforareasnotcountedcanbemadebymultiplyingthesquaremilesofeachunsurveyedareatimesthemoosedensitythatwasobservedinnearbysimilarhabitat.Basedonthisprocedure,wemayhavecounted2.826mooseifalloftheSusitnastudyareaweresurveyed.IntheGu1kanadrainagesystemobserverssaw40percent(28of70)ofthemoosethatwerecollaredapproximatelytwoweekspriortosurveys.Assumingasimilarsightabi1ityofmooseintheSusitnaRiverdrainages,7,065moosemayhavebeenintheSusitnastudyarea.Calculated·compositionratiosfortheSusitnastudyareawere15bullsper100cowsand26calvesper100cows.EvaluationofMooseWinterRange,MooseCondition,andtheLossofWinterRangebyInundation.Observationsofmoosedistributionthroughthewinterindicatedthatseveralhabitattypesweresuccessivelyusedaswinterprogressed.DuringNovembersurveys(Fig.2),mostmoosewereatorneartimberlineorinriparianwillowpatchesabovetimberline.Apreviousgroundsurvey(May31,1974)ofthevegetationneartimberlinehabitatwithinthebigbendoftheSusitnaRiverabovethemouthofGooseCreekwasthebasisforthefollowingobservations.Thisslopejustbelowtreelinecontainsblackspruceandalderasmajortallshrubsandtrees,dwarfbirch,alder,Salixa1axensisandSalixarbuscu10idesasimportantlowshrubspecies,andLedumsp.,Vacciniumvitis-idaeaandCarexsp.asthemoreimportantgroundvegetation.Salixa1axensis,mainlyfoundalongsmalldrainages,wasseverelyhedgedwithmanydecadentstems.Alargepercentageofterminaltwigsofotherwillowspecieswereutilized,andsomeutilizationofalderwasobserved.Smallwillowshrubswerescatteredamongthemoreplentifulblackspruce,dwarfbirch.andalderawayfromdrainages,andmanyofthesewillowshadbeenrepeatedlybrowsedbymoosetosnowlineduringpreviouswinters.Theusualsnow-linehasapparentlybeenatabout2feetonflatportionsoftheseslopes,perhapsindicatingsubstantialwindinthisareainthewinter.Lowbushcranberryisplentifulonthisslopeandisapotentialfoodsource.Theannualavailableforageonthisslopeappearsgreat,butSalixa1axensishasbeenover-utilized,andotherwillowspeciesareat3 leastmoderately-to-heavilyutilized.Mostmooseobservedbelowtimberlinewerealsonearriparianwillowhabitat.Anincreasingconcentrationofmoosealongthemarginsoflarger,lowerelevationdrainageshadbecomeapparentbyJanuary(Fig.3).Thismayhavebeenpartiallyduetoincreasingsnowdepthsthatreducedtheavailabilityoflower-growingalpinewillows.AnincreasinguseofvegetationgrowingonthesteepslopesalongthebanksoftheSusitnaRiverbelowGooseCreekwasnotedduringJanuaryandFebruarysurveys(Fig.3andFig.4).Manyofthewillow-supportingislandsoftheSusitnaRiverwereexamined,anditwasspeculatedthatmostoftheavailablebrowseonthesesiteshadbeenutilized,forcingthemoosetogoelsewhereforfood.Groundexaminationoftheseriverbottomwillow-coveredsandbarsweremadeduringtwodifferentperiods.AgroundexaminationofawillowbaratthemouthoftheTyoneRiverduringMay31,1974wasthebasisforthefollowingobservations.Welandedinitiallyalongsideawillow-coveredriverbarnearthemouthoftheTyoneRiver.Sixtotenfoottallbalsampoplarwithalowdensityoftallerwillowsdominatedthevegetationinthecenterofthebar.Utilizationofthesewillowswaslighttomoderate.Theperipheryofthebarconsistedofa 2to3foothighmoderatelydensestandofwillowsthatappearedtobealmostevenlycropped(mainlymoosecropping,somerabbitclipping)atthepresumedsnowline.FredWilliams,sportfishbiologistconductingthesportfishstudiesatthattime,statedthatutilizationofwillowswasalsohighonthesandbarshehasvisited.DuringApril,1975twowillow-coveredsandbarsontheSusitnaRiverbelowtheMacLarenRiverwereexaminedandthewillowbarnearthemouthoftheTyoneRiverwasrevisited.Thesewillowbarswerecompletelytrackedoverbymoose.Althoughmaximumsnowdepthshadrecededbythetimeofthesesurveys,itappearedthatessentiallyallofthewillowtwigsabovesnowlinehadbeencropped.AmoosecalfthathadstarvedwaslyingontheTyoneRiversandbar.BylateApril,therewererelativelyfewmooseormoosetrackscrossingtheSusitnaRiverbelowthemouthoftheTyoneRiver.ThesnowhadaccumulatedtoabovenormaldepthsinthenorthernportionoftheSusitnastudyarea,andmostmoosewereobservedinrelativelylargeconcentrations.MooserangewasevaluatedduringAprilandwasplacedintolight,moderate,orheavyusecategoriesdependingonthedensityofcumulativetrackingandcratering(Fig.6).ThecontourintervalsofareasthatwouldbeinundatedbytheproposedDevilCanyonandWatanaCreekdamsweresuperimposedonthesemooserangemaps,andcategoriesofmooserangethatwouldbeinundatedweremeasuredtoobtainthefollowingresults.4 lJlProposedDamDevilCanyonWatanaCombinedMaximumWaterLevel14502045MooseRangeCategoryLightModerateHeavyLightModerateHeavyLightModerateHeavyAreaIndundated,Sq.Mi.6.85.6oo20.244.06.825.844.0JJOurdataindicatedthat12.4mi.2wouldbeinundatedbytheDevilCanyonDam(vs11.8mi.2calculatedbytheU.S.CorpsofEngineers)and64.2mi.2wouldbeinundatedbytheWatanaDam(vs67.1mi.2calculatedbytheU.S.CorpsofEngineers).Itisassumedthatthedifferencesareduetoournecessarilycrudemethodsofmeasuringareas.ItisapparentthattheDevilCanyonDamwillhavelessseriousconsequencesbyinundationofmoosewinterrangethantheWatanaDam.ExaminationofFigure6showsthatanyfloodingoftheSusitnaRiveraboveDeadmanCreekwillresultinthelossofheavyormoderately-usedmoosewinterrange.Moosebodyconditionwasevaluatedtocomparemooseindifferentdrainagesandtoseehowwellmoosefaredduringthe1974-75winter.Samplesweretoosmalltocomparemooseindifferentdrainages~sothepooledresultsfortheupperSusitnastudyareaareshownbelow.1AreaConditionRatingPercent(No.)ofMooseAdultsCalvesJ]JJJ'J1CombinedCoalCreek,MacLarenRiver,andClearwaterCreek.Dead:Bony:Moderate:Fat:50%(1)18%(21)65%(75)17%(20)3%(1)72%(26)25%(9)(0) Thisinformationshowsthatthewinteringareasusedbyadultmooseduringthe1974-75winter(withaboveaveragesnowfall)wereadequatetomaintaintheminamoderatelyfatcondition,butmoosecalvesbecamefoodlimited.AnassessmentofmoosewinteringontheOshetnaRiverindicatedthattheadultsweremoderatlyfatbutsnowwasshallowerandbrowsewasmoreavailableincomparisontotheClearwaterCreek-MacLarenRiverarea.CaribouDistributionsandTrails.Observations6fcaribouduringthewintersurveysareshownonFigures2to5.Generally,fewcaribouwinteredintheSusitnastudyarea.SeveralhundredcaribouhavebeenobservedontheSusitnaRiverabovetheDenaliHighwayandtheadjacenthighercountrybetweenValdezCreekandtheEastForkoftheSusitnaRiverduringpreviousNovembersurveys.Atotalof255wereseeninthisareaduringNovember1974(Fig.2)buttheywerenotseenduringsubsequentmonthlysurveys.InadditiontothecaribougroupsshowninFigures2to5,tracksofabandofcariboulocatedjustsouthofDevilCanyonduringNovember(Fig.2)indicatedthatperhaps50-100caribouwereinthatvicinity.Theobservationofwell-defined,ruttedcariboutrailscrossingtheSusitnaRivereastofWatanaCreek(Fig.2)wereofespecialinterest.ThesetrailswereobservedonoppositebanksoftheSusitnaRiver,indicatingthisisatraditionalcrossingarea.OthertrailsnorthofWatanaMountainledtotheSusitnaRiverbutcouldnotbefoundontheopposingnorthbank.AsubstantialportionoftheNelchinacaribouherd(numberingfrom8,000to60,000duringthelasttwentyyears)usuallyappearsaroundtheDeadmanLake-ButteLakeareaduringthesummers,anditispossiblethattheseanimalsmayfrequentlyusetheobservedcrossingsiteoftheSusitnaRiver.NoruttedtrailscrossingtheSusitnaRiverwereseenelsewhereduringthe1974-75surveys.HarvestsandHuntingPressure.Reportedharvestsofmoose,caribouandsheepandannualnumbersofmoosehuntersareshowninTable1.Since1963,anaverageof1,315moosehavebeenharvestedannuallyfromUnit13byanaverageof3,666hunters.AratioofmoosekilledintheSusitnastudyareatomoosekilledinthecenterofUnit13wasderivedfrom1974harvestreports;ifthatratiowasconstantinpastharvests,theSusitnastudyareawouldhaveyieldedanaverageof413mooseannuallyharvestedfromtheupperSusitnaRiverdrainages.Varianceinhunterharvestreportsovertheyearsdoesnotprovidealldataneededtofullyqualifythatfigure.EstimatedcaribouharvestsfromUnit13basedonharvestreportsindicatethatanaverageof5,386caribouannuallyhavebeenharvestedsince1963.TheportionofthiskillfromtheupperSusitnaRiverdrainageshasprobablyvariedwidelyovertheyears,butitmayhaveapproximatedone-thirdoftheaverageannualharvestfromUnit13.6 J1JJrJThereportedharvestfromtheWatanaHillsDallsheepherdisusuallyabout3sheep.ObservationsofOtherMammals.Agroupofapproximately200DallsheepinhabittherangeofhillslyingeastofWatanaCreek-ButteCreekandwestofJayCreek-CoalCreek.ThesesheeparepartiallyisolatedfromthelargersheeppopulationoftheTalkeetnaMountainsbylowcountry.Althoughimmigrationsandemigrationsmayoccasionallybeexpected,inmostyearstheWatanaHillssheepherdisprobablydistinct.AportionofthissheepherdwasseenduringtheAprilsurvey(Fig.6),eventhoughnoeffortwasmadeduringthesurveystoflyatthehigherelevationswheresheepsightingswouldbeexpected.Wolves,wolverines,andfoxeswerefrequentlyseendistributedthroughouttheSusitnastudyarea,butobservationsarenotrecordedhere.DISCUSSIONANDCONCLUSIONSSurveystoobtainmoosedistributionshaveshownmoosetogenerallybeatlowelevationsinthelatewinterandspringandathigherelevationsinthelatefallandearlywinter.TheproposedSusitnaRiverdams,therefore,mayeffectmooseinentiredrainagesystemsandnotmerelythosemooseseenwithinorneartheareasofinundation.Thosesitutaionswheremanymoosehavecrossedortraveledalongrivercorridorsthatwillbefloodedorwillhavefluctuatingwateroricelevelsareofparticularconcern.Asanexampleofmajorrivercrossings,theavailableinformationsuggeststhatmostmooseseenduringearlywinterwithinthe"bigbend"northoftheSusitnaRivercrosstheSusitnaRivertojoinmoosewinteringonthelowerOshetnaRivervicinity.ThesemoosemaystillmostlybesouthoftheSusitnaRiverduringJune.Asanotherexample,thedensemooseconcentrationseensouthoftheMacLarenRiverduringJunemaybemainlythesamewinteringmooseconcentrationthatwasfoundduringAprilonClearwaterCreek.Preventionoftheseseasonalmovementsmayresultinasharpreductioninnumbersoftheaffectedmoose.Iceshelvescreatedbyfluctuatingwaterlevelsinthewinterordeep,wideimpoundmentsmayactascompleteorpartialbarrierstomovements.Inadditiontorivercrossingsaspartofseasonalmigrations,thecriss-crossingofriversbymoosethatspendaportionofthewinternearriversisofconcern.Tracksindicatedthatmooseusevegetationonbothsidesofstreams,anditseemspossiblethatpreventionofmoosecrossingsmaylowerlocalcarryingcapacityby(1)isolatingpocketsofvegetationwherereadyaccessisonlyviathefrozenriverand(2)creatinglocalizedpocketsofbrowsethatareinsufficientinquantitytoattractandsupportmoosebutwouldhavecontributedtothesupportofthosemooseattractedbyadditionalnearbybrowse.7 Moosegenerallyappearedtosuccessivelyusedifferenthabitattypesduringthewinter.Duringearlywinter,mostmoosewereneartimberline,buttheywerefoundincreasinglyatlowerelevationsamongriparianbrowseandalongthesteepslopesoftheSusitnaRiverbymidwinter.Bylatewinter,thesteepslopesoftheSusitnaRiverandmid-elevationsalongtheSusitnaRiver,thathadpreviouslysupportedmoose,wereinfrequentlyusedandmoremooseweremostlyfoundinlargercon-centrationsinwillowpatchesontheSusitnaRiver'smajortributaries.Followingsnowrecessionduringthespring,mostmoosewerethinlydistributedatlowerelevationsexceptforaconcentrationareasouthoftheMacLarenRiver.Whiletheimportanceofsomeareastomoosemaybeproportionaltotheextensiveness,quality,andavailabilityofcontainedbrowse,someareasmaybeofimportanceoutofproportiontothecontainedbrowsedependingonthewintersnowaccumulation,slope,timeofleafingoutofbrowse,orotherfactors.TherelevanceofthispossibilityissuggestedbytheobservedshiftingconcentrationsofmooseinvariousareasoftheSusitnaRiveroritsmajortributariesatdifferenttimeperiods.Over7,000moosemayhavebeenwithinthestudyarea.Naturalmortalityduetopredationisprobablyhighandcalfsurvivaloverthelastdecadehasbeenlow.Thecontainedmoosepopulationmaybesomewhatbelowitsoptimumsize.TheSusitnastudyareabelowtheDenaliHighwaywasnotutilizedbysubstantialnumbersofwinteringcaribou.However,alargeportionoftheNelchinacaribouherdtraditionallycrossestheSusitnaRiverfromitscalvingareanearKosinaCreektospendthesummerintheDeadmanLake-ButteLakevicinity.AmajorcrossingsiteontheSusitnaRiverwaslocatedjusteastofWatanaCreek.TheSusitnaRiverappearstobeaformidableobstacletocalfcaribou.Changingofconditionsatthiscrossingmayormaynotpreventthepassageofadultcaribou,buttheeffectsoncalvesastheyattempttofollowthecowsmustalsobeconsidered.ShouldmodificationsofthiscrossingsitemaketheSusitnaRiverabarriertocariboupassage,thelossofhabitatwoulddirectlylowerthepotentialmaximumpopulationsize.Secondarily,areductioninrecreationalvalueoftheupperSusitnaRiverwouldresultfromthelossofrecreationalcaribouhunting.TheWatanaHillssheepherdlieswithintheSusitnastudyarea,butthesesheepwillprobablynotbedirectlyaffectedbyconstructionofdamsontheSusitnaRiver.Otherbiggameorfurbearerpopulationswouldprobablybeimpactedbyindirecteffectsofincreasedhumanaccessandalterednumbersofpreyspecies,butthesepotentialimpactswerenotstudiedandarepresentlyunknown.Fromthestandpointofrecreationalhunting,theSusitnastudyareamaybeoneofthemostimportantareasinthestate.HarvestdatashowthattheSusitnastudyareacontributesatokensheepharvestbutamoderatelylargemooseharvest.Mostofthemooseharvestfromthe8 11]]J]rJSusitnastudyareaisfromtheDenaliHighway-CoalCreekvicinityandfromtheupperOshetnaRivervicinity.Accesshasrapidlybeenincreasinginrecentyears,andthecentralportionofthisareawillprobablycontributetoanincreasingextentifpastaccesstrendscontinue.TheusualcontributionoftheSusitnastudyareatotheannualcaribouharvestwasassessedasperhapsone-thirdofthetotal.Duringthepastthreeyears,mostmooseandcaribouhuntingactivitywithinUnit13appearedtobeonboththenorthandsouthsidesoftheSusitnastudyarea.AnindirecteffectthatwouldprobablyresultfromconstructionofSusitnaRiverdamswouldbeincreasedaccessintothecenterofGameManagementUnit13throughroadconstructionandwaterwayaccess.Althoughthishasbothpositiveandnegativeimplicationstowildlife,thenegativeaspectspredominate.Amajorincreaseinaccesswouldprobablyrequiremoreintensivemanagementactivitieswitharesultingincreaseinwildlifemanagementcosts.AhighwaycorridoralongsidetheSusitnaRivermayincreasethepotentialbarriertocariboumovements.Inaddition,anyincreasedhumanactivityneartheNe1chinacaribou'scalvinggroundsisundesirable.Insummary,mooseandcaribouarethekeywildlifeassetsoftheupperSusitnaRiver,andthemajoreffectofdamsontheseungulatesisnegative.Moosemaybeimpactedbyblockageofseasonalmovementsacrossoralongrivercorridorsduetofluctuatingicelevelsordeepwaterimpoundmentsandbydirectlossofcriticalwinterrangethroughflooding.Cariboumovementsmaybesimilarlyimpactedbyimpoundedwaterorfluctuatingicelevels,andtheNe1chinacariboucalvingareawillprobablybeexposedtomorehumanactivitysecondarytobetteraccessanddamconstructionactivities.Wildlifemanagementcostswillnecessarilyincrease,andtheoveralleffectofthesedamswillbetodecreasenumbersofmooseandcaribou.TheeffectoftheDevilCanyonDamalonewillbeni1d;theeffectoftheWatanaDamisexpectedtobemoderatelysevere.AnydamontheSusitnaRiverthatimpoundswateraboveDeadmanCreekwillinundatemoderatelyorheavily-usedmoosewinterrange;anydamthatimpoundswateraboveWatanaCreekmaydisruptmooseandcariboumovementswithpotentiallysevereeffects.Thescopeofthispaperdoesnotextendtodownstreamwildlifeortheeffectsthatthedamwouldhaveonthosespecies;effectsmayproveconsiderable.MITIGATIVEACTIONSPriortodamconstructionactivities,detailedstudiesshouldbeconductedtomorefullydeterminetheuseofthisareabyresidentwildlife,togainabetterunderstandingofthepotentialeffectsofdamsonthearea'svegetationandwildlife,andtoevaluaterangeimprovementtechniquesforpossibleusetooffsetlossofmooserange.Ungulatemovementsacrossdrainagesarelargelyseasonal.Whereoperationofdamsresultsinfluctuatingicelevelsthatmayimpedewildlife9 movements,changesintimingoftheseoperationsperhapscouldbemadethatwouldexchangealossofoperatingefficiencyforareducedbarriertoungulatemovements.Lossofmoosewinterrangemaybepartiallycompensatedforbywell-planned,extensiverangerehabilitationoveralongperiodoftime.However,evenagoodandextensiverangeimprovementprogramprobablywon'tfullymitigateanysubstantiallossesofriparianwillowhabitat.10 lJJJ]1rJJ1REFERENCESCITEDAnon.1954.AprogressreportonwildlifeoftheSusitnaRiverbasin.35pp.U.S.D.I.FishandWildlifeService,Juneau.Anon.1960.AdetailedreportonfishandwildliferesourcesaffectedbytheDevilCanyonProject,Alaska.26pp.U.S.D.I.FishandWildlifeServiceandBureauofCommercialFisheries,Juneau.11 Table l.Harvest Data from Game Management Unit 13. 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 Reported Moose Harvest,Unit 13:1735 1607 1331 1553 1552 1512 1219 1329 1815 :712 618 794 Reported Moose Harvest,Center Unit 138 :578 691 299 353 506 512 405 427 540 302 324 394 Estimated Moose Harvest from bupperSusitnaRiverdrainages 537 642 278 328 470 476 376 397 502 281 301 366 Total Moose Hunters,Unit 13:4163 4027 4476 3381 3585 4881 3199 2513 2770 Estimated Caribou Harvest,Unit 13:6300 8000 7100 5500 4000 6000 7800 7247 10,131 555 810 1192 Reported Sheep Harvest,Watana Hills:5 1 7 2 2 2 3 a Actual harvests are higher because of harvests where location of kill was not reported.The center of Unit 13 is that portion of Unit 13 bounded by the Glenn,Richardson,Denali,and Anchorage-Fairbanks Highway. b Estimated harvests from the upper Susitna River drainages during past years were obtained by multiplying annual moose harvests from the center of Unit 13 times the 1974 ratio of (moose harvest from upper Susitna River drainages/ moose harvest in the center of Unit 13). MooseDistributionsSeenDuringJune1974Survey•1I-.'.-.J\).~~':)11r\Figure1.•Moose"'':.'-"~_,)Iif ~/,-Ir'[---..---rJ(\"Figure'-lA H .,'//j.I./.November1974MooseCompositionCDunt.!Areaswithinbrokenlineswerenotcounted..'\'.,'•Moose,0 5Caribou,0SheepJ.rQTraditionalCaribouCrossingAreaT-nlj-'.\,i".jr1J]L1 kJ'te_,OOoJbb'"?5.•.Oo!.ol,'("'-'- •.'.,1.\.'i-'-'=-~':::~':'';':'.:.\--o"!">~~g......,o.,-.~,i"'v~\\\",.,I,..'\~\i'U,'".'.....:\\.,:::......,'..,.,.~,.,"","•f.,..!'.•.':II\'.~'~~:..:.'":'"til::.~:,.,.....:,',','",...::....-II:I~;::..1..-<:IcJ~'l,~r.l"D, "MooseconcentrationsduringtheJanuaryflightloftheSusitnaProject.19751);.'i.":~·7."':~--···"'..:-::"''f""-,•125H}1\~~::;::--.<0,1".'rFigure3.".4.-0'",-0MooseoCaribou",! ' \r,\c:.:.~,002552IJ"D~.-,'V't::I.?26~1\?''\)0~~t?(..;~\,..ot'\'\.\'... eSheep_.:'1aCaribou,."""-,...._"_.,.,I-;:?-.-.o"""r",'\•Moose,MooseconcentrationsduringtheFebruaryflightoftheSusitnaProject.1975tGo)lJ1t1Zo"'e~~-'M",."\~1J''C?t'~,-~''(Pyt)'l',..;;.-o,(1-,\,COLORADOIt,........*·.'.\STATION!\'.,1910-20L'):_:\_/./\"\i'\,.vi"0,.;:--,])J1fJr'"i':'.JJ."....':"-..I.)~S·~J ri':"'~-4T I<69~.'I! }1-J).'.--~1J,,'oJNKLEMINEQ"·,·,co~750_10Dunkle-_::SII....erKingB4M1ne.-•.'i·'Mln~~,,;/,,--...~.~jFigure5.._-'~---MooseconcentrationsduringtheMarchflightoftheSusitnaProject.1975eSheep'.I,'/1{.~.']~:\.~'.." ,~AHL~;-r)":'-~J·~V]".0~('lli.,,,'),,1,..). oSheepoCaribou,•Moose,'M.ooseconcentration'sduringthe·April-flighta·ndareasof6.light,moderate,andheavyutilizationbymoose.Areassurroundedbythebrokenlinesaretheproposedinundatedareas.19751/I,/Broad'4Pass'",r~Y"..-;---:-I/r.:::_l;...J!..,>JJ F lI£~187(f:"DENMIRD,COMMNO,-'__<.)2!S251'12-"'--.._--~".-.\';',,,~-t)!,7ir-<.i°2980(P,\):CROSSWINDLA~l2125-IIt-'-\1,.---',