2016 Genetic Stock Composition Analysis of Chum Salmon From the Prohibited Species Catch of the Bering Sea Walleye Pollock Trawl Fishery and Gulf of Alaska Groundfish Fisheries
June 27, 2016
Pacific salmon (Oncorhynchus spp.) are prohibited species in the federally managed Bering Sea and Gulf of Alaska (GOA) groundfish fisheries, which are subject to complex management rules (NPMFC 2017a,b) that are in part designed to reduce prohibited species catch (PSC). It is important to understand the stock composition of Pacific salmon caught in these fisheries, which take place in areas that are known feeding habitat for multiple brood years of chum salmon (O. keta) from many different localities in North America and Asia (Myers et al. 2007, Davis et al. 2009, Urawa et al. 2009). Determining the geographic origin of salmon caught in federally managed fisheries is essential to understanding the effects that fishing has on chum salmon stocks, especially those with conservation concerns (NPFMC 2012).
In this report, we present the genetic stock composition estimates for the samples of chum salmon PSC collected during 2016 from the U.S. Bering Sea walleye pollock (Gadus chalcogrammus) trawl fishery and the GOA groundfish fisheries. In the Bering Sea, the pollock fishery accounted for more than 98.8% of the total chum salmon taken in the groundfish fisheries (NMFS 2017). In the GOA, the majority (56%) of the chum salmon were caught in the pollock trawl fishery, with the remainder caught in other groundfish fisheries (NMFS 2016).