LEGISLATIVE REPORT 1982 ALEUTIAN ISLANDS SALMON STOCK ASSESSMENT STUDY FWLB 1061 • ·'.. I Ou i LEGISLATIVE REPORT 1987. ALEUTIAN ISLANDS SALMON STOCK ASSESSMENT STUDY JANUP..RY 1982 A.LASKA DEPARTMENT OF FISH AND GAf\lE DIVISION OF COMMERCIAL FISHERIES P.O. BOX 3-2000 JUt~EAU, ALASY.A 99801 0 en I' C'\1co 0 0 0 ARLIS LO LO Alaska Resources I' ('I) Library & Information Services ('I) Ant''h~'rn.--< ft / 1 -. • I·.. ~-' > 1 ·:C /"1 ;1 :-• \ :-l LEGISLATIVE REPORT 1982 ALEUTIAN ISLANDS SALMON STOCK ASSESSMENT STUDY INTRODUCTION The 1980 Legislature requested that the Department of Fish and Game provide it with data and statistics on the salmon streams and historic salmon catches in the Aleutian Islands. This information was to be included in a joint report with the Commercial Fisheries Entry Commission concerning the. establishment of the Aleutian I stands as a seporate administration area which could allow local people the opportunity to fish salmon. The report was less than complete, in regards to the lack of data available concerning Aleutian salmon streams The Department requested funding to conduct a compreheosive research study of the Aleutian Islands salmon resources and in 1981 the legislature allocated $211 ,000 for that purpose. Since funding was too late for· the 1981 season the project began during the 1982 field season. Because of the cyclic odd and even year difference of return of pink salmon, the prinary specie of salmon in the area, it would be desirable to conduct the surveys for two consecutive years. Unfortunately operational costs were greater than anticipated and the majority of the funds were expended on the high priority field surveys this season. If additional funding is made available the areas of highest commercial potential will be reassessed in the summer of 1983. The 1982 AleuUan I stands salmon study encompassed the area west of Unimak Pass to Attu Island, a distanc(' of roughly 1 ;ooo miles (Figure 3). Nunerous islands of varying charetcteristics mcke up the Aleution Chain, ranging fror1 nere rocky pin points to 70 mite _lcng UtTJnak Island. Thirteen major islnnds and several minor land nasses were investigC!ted reg<lrding anadromous strenrn rotential. Prior to this study Departrnental knowledge of the area was sparse with the exception of Unalaska Island. The September 14, 1974 anadromous stream catalog lists 444 anadrornous streams in the /l.leutian Islands. One hundred and five of these streams are listed for Unalaska Island and eastward, leaving 339 listed strearns of which little was known from Umnak to Attu Island. As a result of this study an additional 157 systems were found to have anadromous fish populations, while 44 systerns were deleted. The 1982 field study was conctucted to research the potential of the Aleutian Islands for comMercial salmon fisheries. This research was conducted with the cooperation and support of the U.S. Fish and Wildlife Service, U. 5. Coast Guard, U.S. Navy and U.S. Air Force. The islands with the highest potential for commercial harvest were examined. Basic studies on a prioritized basis included: 1) Species identification and enuneration. 2) Cataloging, photographing, and recording physical characteristics of salmon streams. 3) Definition of spawning areas. 4) Recording streaMs with a potential for rehabilitation and enhancement. 5) Examination of returning fish for high seas salnon tags. 6) Gathering length/weJght and age data ]_I of salmon at one major stream on each island examined. 7) Collection of tissue samples from pink salmon for stock separation studies. This report will focus on the primary objective of the project, salmon enumeration and species identification. The Westward Region Report to the Alaska Board of Fisheries contains a mere descriptive account of this study. A later publication in the ADF&G Technical Report series will provide greater detail which will include a photographic stream catalog, stream habitat information and a summary of salmon length, weight and age data. The University of Alaska, Juneau, will issue a separate publication on results of the pink salmon stock seperation study basect en tissue samples collected by this project. 11 Otolith!' and/or scCJies were taken fr0rr1 rf'd nnd chum salMon when they were ercountered in si~nificant nuf'lbers to sar'lple. - 1 - Flying hours during this study were often restricted by severe weather, thus reducing the ability of the study team to achieve all of its objectives for each stream. Salmon enuMeration, the primary objective of this study, was carried out for every potential stream system between Unalaska end Kiska, except for one lake on Tanaga Island. Agattu (an island with a very low potential for salmon} was deleted due to weather delays early in the project. Attu Island received an intense foot survey effort but the rugged topography of the island restricted the study to approximately 110% of the streams on the island. The tiMing of this study was focused on obtaining the best data on pink salrnon. Out of necessity we were unable to assess all runs of each species of salMon equally well. Counts of other species are acknowledged as underestimates. The study may have been too late to accurately assess early runs of sockeye and chum salmon. It probably was too short in duration, because coho were just beginning to enter fresh water at the end of the field worl<. _ High winds and water turbulence Made it nearly impossible to make any counts of coho schooling in saltwater.. The amount of tiMe required to completely assess coho would probably not be cost effective due to c'elays from weather after the 15th of September. It is acknowledged that counts of species other than pinks were underestimates of the actual stock size, however, extensive examination of potential habitat for these species leads the investigator to conclude that the actual numbers of these species is quite small on most islands. There were no systems which would provide for spawning and rearing of king salmon. King salmon landed in the Aleutians are most like "feeder kings" intercepted while migrating through the Aleutians. Salmon weight information, summarized by species in Table 2, should not be interpreted as being maximum weights. The project attempted to sample the freshest indivic:uals in at least one major system on each island surveyed. 1n some cases, as the result of the timing of the runs it was necessary to sample fish which had been in freshw~ter for varying lengths of tine and had lost weight when compared to sea run fish. Therefore, the data gathered should be used for relative cor1parisons. - 3 - • Pink salmon sampled in this study were at least 1 pound larger than expected. The largest salmon encountered were from an Atka Island sample. These fish weighed an average of 4. 24 pounds. The average weight of fish sampled was 3. 8 pounds. The sockeye salMon that were sampled all were spawning with the exception of those on the Kagalaska Island. These fish were smCIIler than most mainland runs averaging 4.6 pounds, with the bright fish on Kagalaska weighing 4.4 pounds. Only three chum runs of any significance were located during the study. The largest (1 ,350 sc.lmon) was on Atke1 Island. The one run sanpled on. Atka averaged 7.6 pounds. It should be noted that these fish were spawning, and their weights were probably low compared to fresh fish. FIELD OPERATIONS Umnak to Kiska: The study team was made up of the project leader, one Fishery Biologist I seasonal, 2 Fishery Biologists from the University of Washington Fisheries Research Institute, a helicopter pilot/mechanic and a vessel crew of four. During the 51 day charter, research was conducted from Unalaska Island to Kiska. The University of Washington research· vessel ALASKA was equipped with a 20' x 21' helicopter landing pac!. A chartered Bell Jet Ranger helicopter was used to deploy field crews and to conduct aerial stream surveys of the islands with the vessel acting as base of operations and logistical center. The use of a he'icopt~r all()wed stream surveys to be conducted where steer terrain and weather wPuld h<we made fixed wil"'a and foot survevs impossible. The vessel also carried a 16' Zodiak raft and Boston Whaler which wc>re utilized for tr<~nsportaticn for foot surveys durina weather too inclenert for helicopter oper()tions. - 4 - The weather delays prior to reaching Kisl<a resulted in canceling an attempt to provide contingency helicopter surveys of Attu and Agattu Islands. Unalaska lslar.d East to Unim<:~k Pass; Aerial stream surveys of major systems on Unalaska and Akutan Islands were conducted by the Alaska Peninsula( Aleutian Islands Area Manager1ent Staff. Annual stream surveys were flown out of Dutch Harbor in August and early September to assess escapements to major systems. Surveys were conducted by this project in the areas of Unalaska which previously had received little or no assessment effort. This included Beaver Inlet, the south side, and the southwest panhandle of the island west of Skan Bay. Attu Island: Attu I stand is potentially the most productive island in the western Aleutians for salmon, based on the limited information available. Due to this potential and geographical separation from the other f:1ajor Aleutian I stands, a separate field study was carried out on Attu. In May and June reconnaissance trips were conducted by the project leader to Attu Island to examine topographic features of the island, photograph potential salmon streams, determine logistical needs and the feasibility of a ground crew investigation. Major ground investigation of salmon strear:1s on Attu was conducted late July through early September. The ground crew study tenm consisted of two seasonal Fishery Biologists equipped with two three wheel motorcycles and an inflatable raft.