ABL staff were involved in several bilateral Pacific Salmon Commission (PSC) activities during the last quarter. These activities included participation in the Yukon River Joint Technical Committee, the Northern Boundary Technical Committee, the Chinook Technical Committee, and the Transboundary Technical Committee Subcommittee on Enhancement.
PSC Yukon River Joint Technical Committee (JTC)
Jim Murphy attended the Yukon River Joint Technical Committee (JTC) meeting in Fairbanks, Alaska, 22-24 February 2011, and presented juvenile Chinook and chum salmon data collected during the NMFS pelagic trawl surveys in the northern Bering Sea. Jim also provided updates on salmon bycatch in the Bering Sea Aleutian Island and Gulf of Alaska groundfish fisheries. The JTC is charged with evaluating scientific data related to the harvest, population assessment, and research on Canadian-origin salmon stocks. Data are reviewed and the Technical Committee uses this information to advise the Yukon River Panel, which establishes policy for resource management of Canadian-origin salmon stocks.
Yukon River Chinook salmon have been classified by the Alaska Board of Fisheries as a stock of yield concern since 2000. Through significant reductions in commercial harvests and restrictions placed on subsistence harvests, escapement goals have been generally met throughout the Alaska portion of the Yukon River drainage. However, border passage goals established by the Yukon River Panel for Canadian-origin Chinook have not been met in 3 of the last 4 years (2007, 2008, and 2010). The combination of recent poor runs and the level of uncertainty present in pre-season and in-season assessments of run size have contributed to the failures to meet border passage agreements.
The ABL received funding support in 2011 for marine research on the juvenile life-history stage of Yukon River Chinook salmon ($370,000) by the Arctic Yukon Kuskokwim Sustainable Salmon Initiative and the Alaska Sustainable Salmon Fund. The funding will provide the 2011 assessment of juvenile Yukon River Chinook salmon and will enable the juvenile data to be evaluated in terms of recent losses in production and its potential to reduce uncertainty in pre-season assessments of adult returns.
PSC Northern Boundary Technical Committee (NBTC)
Michele Masuda and Bill Heard participated in bilateral meetings of the Northern Boundary Technical Committee (NBTC) at the Pacific Salmon Commission Post Season Meeting in Vancouver, British Columbia, 10-13 January 2011. Normally this committee meets to determine the annual allowable harvest of sockeye salmon from the Nass and Skeena Rivers in Alaska District 104 purse seine and District 101 drift gillnet fisheries, along with annual allowable harvest of pink salmon caught in Canadian boundary area net and troll fisheries. Specific formulas in the Pacific Salmon Treaty provide for limits on the number of sockeye and pink salmon that originate in one country that can be caught in fisheries of the other country. The primary focus of meetings this year, however, was to evaluate blind tests of known populations of sockeye salmon for comparing two genetic stock identification methods, DNA microsatellite and single-nucleotide polymorphisms (SNPs) and scale pattern analysis (SPA) used in identifying stock origins in mixed stock fisheries.
Stock composition estimates of Canadian fisheries historically have been derived from DNA microsatellite analyses by Fisheries and Ocean Canada and by scale pattern analysis in U.S. fisheries by the Alaska Department of Fish and Game (ADF&G). The ADF&G is now planning to shift from scale pattern analysis to genetic-based single-nucleotide polymorphism analysis of catch samples from Alaska fisheries. Blind tests of all three stock identification techniques were developed from known populations of both Canadian and Alaska stocks to validate changes from scale pattern analysis to single-nucleotide polymorphism analysis for analyzing stock compositions in Alaska fisheries.
Four stock mixtures involving known Alaska, Nass, Skeena, and Fraser sockeye populations with different percentages of each group were developed for blind test analyses using the three analytical procedures. Fraser River sockeye were included in some of the mixtures since annual variations in migration patterns cause significant numbers of Fraser sockeye to be caught in Alaska fisheries in some years, especially in the District 104 seine fishery. Results from most initial blind tests were within acceptable ranges for standard errors; however, test results in some mixtures were equivocal, suggesting the need for higher resolution which may require expanding single-nucleotide polymorphism alleles used in the initial test for clarification. Additional match sample comparison with DNA microsatellite, scale pattern analysis, and single-nucleotide polymorphism analysis will also be run to determine if there are any systematic sampling biases in these procedures.
PSC Chinook Technical Committee (CTC)
Andy Gray and ABL contractor Alex Wertheimer participated in bilateral Chinook Technical Committee discussions at the Annual PSC Meeting in Portland, Oregon, on 14-18 February 2011. These meetings focused on finalizing the report for a Chinook Salmon Total Mortality Management Regime for aggregate abundance-based management (AABM) fisheries in both countries. Wertheimer, as U.S. Co-Chair of the Chinook Technical Committee's Total Mortality Working Group (TMWG), also participated in several other bilateral discussions in fleshing out final agreements for this report. The report provides mechanisms, as required by the Treaty, for transitioning AABM fisheries based on landed catch to one based on total mortality. A total mortality management regime will account for both catch and associated incidental mortality in AABM fisheries and constrain the fishery based on the cumulative impact. The AABM fisheries involved include Southeast Alaska troll, sport and net fisheries, Northern British Columbia troll and sport fisheries, and West Coast Vancouver Island troll and sport fisheries.
Development of a total mortality management regime required the TMWG to establish ratios from the base period 1985-95 between landed catch and the associated mortalities from fishing, adjusted for a landed catch equivalency (LCE). This involved a lengthy process of developing metrics for transferring different kinds of fishing mortalities between and within different gear types into a procedure for adjusting the annual abundance index into an allowable landed catch for each AABM fishery. The abundance index, derived from annual calibrations of the CTC model, determines the allowable landed catch that is detailed in Table I of Annex IV, Chapter 3 in the Treaty.
Under a total mortality regime, limits on AABM fisheries are based on total mortality rather than landed catch that requires adjusting allowable LCE under a given abundance index. Initial assumptions in the 2009 Treaty modification calling for implementing a total mortality regime in 2011 was that fishing under total mortality, additional catch limits would be imposed on most AABM Chinook fisheries. This, however, turned out not to be the case. Under a total mortality modified abundance index most AABM fisheries will be allowed an increase in LCE. The primary reason for this paradoxical outcome appears to be the required use of the 1985-95 base period as the foundation for making transitions to a total mortality regime. Adjustments to coastwide Chinook fisheries management since 1995 appear to have abrogated many of the deleterious mortality related fishing practices that were common during the base period.
An important question now is how Pacific Salmon Commissioners will deal with this issue as the Treaty requires implementation of total mortality management for AABM Chinook fisheries under the 2009 Agreement.
PSC Transboundary Technical Committee (TTC)
The Transboundary Technical Committee met on 2-4 March 2011 in Juneau. John Joyce attended as a member of the Transboundary Technical Committee Enhancement Subcommittee. Operational plans for the 2011 season were reviewed including a review of Northern Fund request for proposal status along with allocations and operational plans for funded projects. Preliminary forecasts for the Taku, Stikine, and Alsek Rivers were exchanged bilaterally with Canadian counter parts and in-season management plans were adopted. Sara Gilk from ADF&G's Gene Conservation Laboratory provided an update on the status of genetic stock identification programs for several transboundary river projects.
The Enhancement Subcommittee met to update progress on sockeye enhancement projects on both the Taku and Stikine Rivers. The Stikine Enhancement Plan and Taku Enhancement Plan are not part of the treaty process and are directly tied to the harvest share agreements between the United States and Canada. The bilateral committee set technical goals for the enhancement process and provided criteria for measuring project success. In addition, the subcommittee responded to Transboundary River Panel direction to optimize methodologies for brood stock collections and other extended rearing enhancement activities to maximize yield from enhancement projects. The panel also requested the enhancement subcommittee to optimize protection of wild stock productivity in the Tatsamenie Lake in the Taku River drainage and in Tahltan and Tuya Lakes in the Stikine River drainage.
PSC Letter of Agreement Funding Issues
Under a 1999 PSC-related Letter of Agreement (LOA), special funding is provided from Congress to the U.S. Section of the Chinook Technical Committee to support research associated with specific U.S. Chinook salmon issues. One important issue was the implementation of mass marking programs of large numbers of Chinook salmon produced in some U.S. hatcheries that could threaten the integrity of the coast-wide coded wire tagging (CWT) program that was instrumental in helping implement the Pacific Salmon Treaty. This concern came about when mass marked Chinook salmon smolts from hatcheries were identified with clipped adipose fins that originally had been sequestered for use as a visible indicator only with CWT-tagged fish. Some LOA-supported research, therefore, is directed at research associated with additional ways of marking and identifying individual groups of Chinook salmon.
Two ongoing LOA projects at ABL were recently approved for additional funding. Principal investigator Andy Gray's proposal to the U.S. Chinook Technical Committee was approved to continue work on parental based tagging of Chinook salmon at the Little Port Walter (LPW) Marine Station. This is a DNA-based technique that has important implications for an alternative to marking fish with CWTs and determining performance of individual family matings in fish stocks. Adrian Celewycz serves as principal investigator on a different LOA project at LPW. Adrian's project, designed to evaluate effects of ventral fin clips on size, age at return, and marine survival schedules of Alaska stream-type Chinook salmon, was also approved for funding in FY-11 and FY-12.
By Bill Heard, Jim Murphy, Michele Masuda, Andy Gray, Alex Wertheimer, John Joyce, and Adrian Celewyz
