Genetic stock composition analysis of chum salmon from the prohibited species catch of the 2014 Bering Sea walleye pollock trawl fishery and Gulf of Alaska groundfish fisheries.

• Main Authors: Kondzela, Christine M., Whittle, J. A., Yates, D., Vulstek, Scott C., Nguyen, Hv. T. Hanhvan T., Guyon, Jeffrey Robert
• Format: Text
• Language: unknown
• Published: U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center. 2016
• Subjects: Chum salmon > Bering Sea > Genetics > Analysis.; Chum salmon > Alaska > Alaska, Gulf of > Genetics > Analysis.; Yukon; Bering Sea; Gulf of Alaska; Pacific; Keta; Alaska
• Online Access: https://dx.doi.org/10.7289/v5/tm-afsc-314; https://repository.library.noaa.gov/view/noaa/8688

A genetic analysis of the prohibited species catch (PSC) of chum salmon (Oncorhynchus keta) collected during 2014 from the federally managed walleye pollock (Gadus chalcogrammus) trawl fishery in the Bering Sea and the federal groundfish fisheries in the Gulf of Alaska (GOA) was undertaken to determine the overall stock composition of the sample sets. Samples were genotyped for 11 microsatellite markers from which stock contributions were estimated using the current chum salmon microsatellite baseline. In 2014, one genetic sample was collected for every 30.2 chum salmon caught in the Bering Sea midwater trawl fishery. The evaluation of sampling in the Bering Sea based on time, location, and vessel indicated that the genetic samples were representative of the total chum salmon PSC in the Bering Sea. Based on the analysis of 1,741 chum salmon collected throughout the 2014 Bering Sea trawl fishery, the largest stock group in the catch was Northeast Asia (37%), followed by Eastern GOA/Pacific Northwest (PNW) (24%), Southeast Asia (19%), Western Alaska (18%), Upper/Middle Yukon (2%), and Southwest Alaska (< 1%) stocks. The regional stock estimates for the 2014 chum salmon caught in the Bering Sea were similar to those in 2013, with the exception of a lower contribution from Upper/Middle Yukon stocks in 2014. As in previous years, there were some significant differences in stock proportions throughout the season and across areas. For the first time, a small set of chum salmon samples from the GOA groundfish fisheries were available for genetic analysis. The highest proportion of the 273 chum salmon sampled in the GOA groundfish fisheries were from Eastern GOA/PNW (92%) stocks.