Auke Bay Laboratory (ABL)

Regional Mark Committee Meeting

In May 2003, Adrian Celewycz from the Auke Bay Laboratory (ABL) represented the Alaska Fisheries Science Center (AFSC) and the NMFS Alaska Region at the annual meeting of the Regional Mark Committee of the Pacific States Marine Fisheries Commission (PSMFC). The committee evaluates regional marking proposals and coordinates coast-wide agreements on marking salmonid stocks to ensure integrity of stock identification information provided by marking, sampling, and data exchange programs with emphasis on coordinating and protecting coastwide coded-wire tag (CWT) programs. Regional Mark Committee members are responsible for maintaining and updating their agency's CWT information including release, recovery, and catch/sample and catch/effort data in the coastwide CWT database.

The ABL is responsible for maintaining release and recovery information of all CWT salmonids from Federal research programs conducted in Alaska, and recovery, catch/sample, and location information of CWT salmonids from bycatch in the Gulf of Alaska trawl fishery and the Bering Sea-Aleutian Islands trawl fishery. Celewycz presented an annual update from 2001 of CWTs recovered on the high seas, including both fisheries and research recoveries.

In 2001, fishery observers on U.S. groundfish vessels in three domestic trawl fisheries in the North Pacific Ocean, the Gulf of Alaska, and the Bering Sea recovered 185 CWTs from a total of more than 40,000 salmon examined; 99% of tagged fish were chinook salmon. Salmon are prohibited species in these three high-seas fisheries and are harvested only as bycatch.

In the 2001 trawl fishery targeting Pacific whiting in the North Pacific Ocean off Washington, Oregon, and California (WA-OR-CA), chinook salmon was the only species with CWT recoveries; 129 CWTs were recovered. Of the total 1,200 salmon examined, 99% were chinook salmon, with coho salmon, and chum salmon making up the other 1%.

Recovery of CWTs in two high-seas research programs was also described. Juvenile salmon were captured in trawl surveys on the Bering Sea as part of a cooperative program between ABL's Ocean Carrying Capacity Program and the University of Washington. Out of 400 chinook salmon, 2,900 chum salmon, and 1,425 coho salmon examined, 6 chinook salmon with CWTs and 3 coho salmon with CWTs were recovered. During gillnet research on the high seas by the Fisheries Agency of Japan, four steelhead with CWTs and one coho salmon with a CWT were recovered.

Catch year 2001 was the last year for which the AFSC was responsible for reporting CWTs recovered from the salmon bycatch of the whiting fishery off WA-OR-CA. The NMFS Northwest Region began managing observer programs for both the whiting fishery and the groundfish fishery off WA-OR-CA in 2002 and was to begin reporting CWTs recovered from salmon bycatch in these fisheries to the coastwide CWT database this year (2003); however, no new data on salmon bycatch from these fisheries have been received by the PSMFC.

By Adrian Celewycz and Bill Heard.



Emigrant Salmonid Counts at Auke Creek Weir

In June 2003, ABL personnel concluded 120 consecutive days of weir operations and fish counting, sampling, and marking at the Auke Creek weir. The weir was installed 3 March and operated in the downstream mode until 30 June. This was the twenty-fourth consecutive year of downstream counts of all emigrant salmonids at Auke Creek.

The emigration of pink salmon fry was the second-earliest on record at Auke Creek with the midpoint of emigration on 4 April; the average for all years is 21 April. Emigration timing for other salmonids at Auke Creek was earlier than the average, but only by 2-5 days. Sockeye salmon counts were above average, while pink and coho salmon, Dolly Varden, and cutthroat trout counts were below average.

The 2003 sockeye smolt count of 21,154 was 4,000 fish above the 1980-2003 average. Yearling smolts accounted for 54% of the migration and averaged 3.4 g and 74 mm, while 2-year-old smolts averaged 10 g and 107 mm. Yearling smolts and 2-year-old sockeye smolts were below the average size observed over the last two decades.

More than 95,000 pink salmon fry emigrated this year, about 20,000 below the 1972-2003 average. However, the 2003 emigration had the largest number of even-year brood, pink salmon fry since the 1992 brood. The coho smolt emigration of 3,574 was the second lowest count on record for Auke Creek. The long-term average for 1980-2003 is 6,189. Auke Lake coho smolt production has been decreasing since 1980.

A total of 254 cutthroat trout were counted during the downstream migration at Auke Creek, slightly less than the average of 261. Cutthroat trout numbers have been decreasing since 1994. The Dolly Varden count this year was 5,067, the second lowest since 1986 and less than the long-term average of 6,307. Dolly Varden emigrations have steadily decreased since 1995. Several studies are under way at Auke Creek under a cooperative agreement with NMFS, the Alaska Department of Fish and Game (ADF&G), and the University of Alaska Fairbanks. Auke Creek, the site of a cooperative project on wild coho salmon smolt tagging, is one of four sites in northern Southeast Alaska where wild salmon smolts are tagged annually. Cooperative cutthroat trout projects at Auke Creek for 2003, tagging and recovery of downstream migrants with Passive Integrated Transponder (PIT) tags, and population estimate work in Auke Lake were successfully concluded for the spring season.

Judy Lum, a graduate student and fishery biologist in charge of ADF&G projects at Auke Creek, successfully completed her thesis on wild coho salmon from Auke Creek. The work revealed that there are significant intra-annual differences in weekly marine survival of coho salmon smolts leaving Auke Creek.

By Jerry Taylor.

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AFSC Quarterly
Research Reports
April - June 2003