Genetic Stock Composition Analysis of Chum Salmon Bycatch Samples from the 2005 Bering Sea Groundfish Fishery

摘要

The Bering Sea provides habitat for chum salmon from many populations throughout their geographic range during their residence in the marine environment (Abe et al., 2007; Friedland et al., 2001). In some years, large numbers of chum salmon are incidentally caught as bycatch in the Bering Sea trawl fishery for walleye pollock (Stram and Ianelli, 2009; Witherell et al., 2002). When escapement of chum salmon in several western Alaska areas declined in the early 1990s (Eggers, 1995), the incidental chum salmon harvest in the trawl fishery became of concern. This led to changes in the management of that fishery (Ackley, 1997) and the first genetic stock identification analyses of chum salmon bycatch. It was during this time that many fishery agencies worked to develop coastwide genetic baselines that could be used to estimate the stock contributions to mixtures of fish such as chum salmon (Seeb et al., 1995). The Auke Bay Laboratory analyzed samples from three years in the mid-1990s to estimate the regional contribution of chum salmon stocks to the bycatch. More recently, numbers of chum salmon caught as bycatch in the Bering Sea groundfish fishery have increased to a high of over 700,000 fish in 2005. This report presents preliminary genetic stock identification results for a subset of samples collected in 2005.