A genetic analyses of samples from the Chinook salmon (Oncorhynchus tshawytscha) bycatch from the 2007-2013 Bering Sea-Aleutian Island and Gulf of Alaska trawl fisheries for walleye pollock (Gadus chalcogrammus) were undertaken to determine the overall stock composition of the bycatch. Samples were genotyped for 43 single nucleotide polymorphism (SNP) DNA markers and results were estimated using the Alaska Department of Fish and Game (ADF&G) SNP baseline.

A genetic analysis of samples from the chum salmon (Oncorhynchus keta) bycatch of the 2009 Bering Sea walleye pollock (Theragra chalcogramma) trawl fishery was undertaken to determine the overall stock composition of the sample set. Samples were genotyped for eleven microsatellite markers and results were estimated using the current chum salmon microsatellite baseline. In 2009, genetic samples were collected opportunistically as part of a special project, but sample biases have the potential to affect stock composition analysis results. Consequently, stock composition estimates apply to the sample set and may not represent the entire chum salmon bycatch. Based on the analysis of 1,437 chum salmon bycatch samples collected throughout the 2009 Bering Sea trawl fishery, North Asian (30%), East Asian (34%), and Eastern Gulf of Alaska/Pacific Northwest (18%) stocks dominated the sample set, with smaller contributions from Western Alaska (13%), Upper/Middle Yukon River (2%), and Southwest Alaska (4%) stocks. The estimates for the 2009 chum salmon bycatch sample set were similar to the 2005 chum salmon bycatch estimates.

A genetic analysis of samples from the chum salmon (Oncorhynchus keta) bycatch from the 2011 Bering Sea walleye pollock (Theragra chalcogramma) trawl fishery was undertaken to determine the overall stock composition of the sample set. Samples were genotyped for 11 microsatellite markers and results were estimated using the current chum salmon microsatellite baseline. In 2011, genetic samples were collected systematically as part of a special project to reduce sample biases that exist in collections from previous years that have the potential to affect stock composition analysis results. One genetic sample was collected for every 31.1 chum salmon caught in 97% of the midwater trawl fishery that was sampled. Evaluation of sampling based on time, location, and vessel indicated that the genetic samples were representative of the total bycatch. Based on the analysis of 1,472 chum salmon bycatch samples collected throughout the 2011 Bering Sea trawl fishery, the Eastern Gulf of Alaska (GOA)/Pacific Northwest (PNW) stocks dominated the sample set (38%), with moderate contributions from East Asian (17%), North Asian (18%), and Western Alaska (16%) stocks, and smaller contributions from Upper/Middle Yukon River (9%) stocks. The estimates for the 2011 chum salmon bycatch sample set differed from the 20052010 estimates, indicating a change in the consistency of the regional stock contributions across the previous 6 years, possibly due to the larger proportion of bycatch caught later in the season and in the more southeastern NMFS reporting areas in 2011. There were significant spatial differences in stock distribution, with the Asian stocks dominating the central Bering Sea area and the Eastern GOA/PNW stocks dominating the southeastern Bering Sea. Analysis of temporal groupings revealed changes in stock composition during the course of the season with decreasing contribution of East Asia and Upper/Middle Yukon stocks and increasing contribution of Eastern GOA/PNW stocks over time.

A genetic analysis of samples from the chum salmon (Oncorhynchus keta) bycatch of the 2007 Bering Sea walleye pollock (Theragra chalcogramma) trawl fishery was undertaken to determine the overall stock composition of the sample set. Samples were genotyped for eleven microsatellite markers and results were estimated using the current chum salmon microsatellite baseline. In 2007, genetic samples were collected opportunistically as part of a special project, but sample biases have the potential to affect stock composition analysis results. Consequently, stock composition estimates apply to the sample set and may not represent the entire chum salmon bycatch. Based on the analysis of 1,279 chum salmon bycatch samples collected throughout the 2007 Bering Sea trawl fishery, North Asian (35%), East Asian (34%), and Eastern Gulf of Alaska/Pacific Northwest (16%) stocks dominated the sample set, with smaller contributions from Western Alaska (10%) and Upper/Middle Yukon River (5%) stocks. The estimates for the 2007 chum salmon bycatch sample set were similar to the 2005, 2006, and 2009 chum salmon bycatch estimates, suggesting consistency of the regional stock contributions across years. Analysis of temporal groupings within the groundfish B season revealed changes in stock composition during the course of the season with decreasing contribution of Upper/Middle Yukon stocks over time, but leaves unanswered whether these changes are due to temporal or spatial differences in the sample set.

A genetic analysis of samples from the chum salmon (Oncorhynchus keta) bycatch of the 2008 Bering Sea walleye pollock (Theragra chalcogramma) trawl fishery was undertaken to determine the overall stock composition of the sample set. Samples were genotyped for eleven microsatellite markers and results were estimated using the current chum salmon microsatellite baseline. In 2008, genetic samples were collected opportunistically as part of a special project, but sample biases have the potential to affect stock composition analysis results. Consequently, stock composition estimates apply to the sample set and may not represent the entire chum salmon bycatch. Based on the analysis of 629 chum salmon bycatch samples collected throughout the 2008 Bering Sea trawl fishery, North Asian (27%), East Asian (35%), and Eastern Gulf of Alaska/Pacific Northwest (24%) stocks dominated the sample set, with smaller contributions from western Alaska (7%) and Upper/Middle Yukon River (6%) stocks. The estimates for the 2008 chum salmon bycatch sample set were similar to the 2005, 2006, 2007, and 2009 chum salmon bycatch estimates, suggesting consistency of the regional stock contributions across years. Analysis of temporal groupings within the groundfish B season revealed changes in stock composition during the course of the season with decreasing contribution of Eastern Gulf of Alaska/Pacific Northwest stocks over time, but leaves unanswered whether these changes are due to temporal or spatial differences in the sample set.

A genetic analysis of samples from the chum salmon (Oncorhynchus keta) bycatch of the 2006 Bering Sea walleye pollock (Theragra chalcogramma) trawl fishery was undertaken to determine the overall stock composition of the sample set. Samples were genotyped for eleven microsatellite markers and results were estimated using the current chum salmon microsatellite baseline. In 2006, genetic samples were collected opportunistically as part of a special project, but sample biases have the potential to affect stock composition analysis results. Consequently, stock composition estimates apply to the sample set and may not represent the entire chum salmon bycatch. Based on the analysis of 1,367 chum salmon bycatch samples collected throughout the 2006 Bering Sea trawl fishery, North Asian (31%), East Asian (29%), and Pacific Northwest (25%) stocks dominated the sample set with smaller contributions from Western Alaska (8%) and Upper/Middle Yukon River (6%) stocks. The estimates for the 2006 chum salmon bycatch sample set were similar to the 2005 and 2009 chum salmon bycatch estimates, suggesting consistency of the regional stock contributions across years. Analysis of temporal groupings within the groundfish B season revealed changes in stock composition during the course of the season with decreasing contribution of Upper/Middle Yukon stocks over time, but leaves unanswered whether these changes are due to temporal or spatial differences in the sample set.

A genetic analysis of samples from the chum salmon (Oncorhynchus keta) bycatch from the 2012 Bering Sea walleye pollock (Gadus chalcogrammus) trawl fishery was undertaken to determine the overall stock composition of the sample set. A genetic analysis of chum salmon collected during a test of a salmon excluder device was also conducted. Samples were genotyped for 11 microsatellite markers and results were estimated using the current chum salmon microsatellite baseline. In 2012, genetic samples were collected systematically as part of a special project that commenced in 2011 to reduce sample biases that exist in collections from previous years and have the potential to affect stock composition analysis results. One genetic sample was collected for every 31.5 chum salmon caught in the 98% of the midwater trawl fishery that was sampled. Evaluation of sampling based on time, location, and vessel indicated that the genetic samples were representative of the total bycatch. Based on the analysis of 673 chum salmon bycatch samples collected throughout the 2012 Bering Sea trawl fishery, the North Asian stocks dominated the sample set (39%), with moderate contributions from East Asian (20%), Eastern Gulf of Alaska (GOA)/Pacific Northwest (PNW) (18%), and Western Alaska (14%) stocks, and smaller contributions from Upper/Middle Yukon River (7%) and Southwest Alaska (2%) stocks. The estimates for the 2012 chum salmon bycatch sample set differed from the mean of the 20052011 estimates for the two Asian regions, but not for the North American regions. The pattern of changes of regional stock contributions over three time periods in 2012 differed from previous years for some regions. There were some spatial differences in stock distribution; e.g., the East Asian stock contribution was higher in the central Bering Sea than in the southeastern Bering Sea. As with the bycatch samples, the salmon excluder device test samples included fish from all geographic regions despite being collected at small spatial and temporal scales.

A genetic analysis of samples from the chum salmon (Oncorhynchus keta) bycatch of the 2005 Bering Sea walleye pollock (Theragra chalcogramma) trawl fishery was undertaken to determine the overall stock composition of the sample set. Samples were genotyped for eleven microsatellite markers and results were estimated using the current chum salmon microsatellite baseline. In 2005, genetic samples were collected opportunistically as part of a special project and supplemented with archived scales from the Observer Program. Sample biases have the potential to affect stock composition analysis results; consequently, stock composition estimates apply to the sample set and may not represent the entire chum salmon bycatch. Based on the analysis of 1,084 chum salmon bycatch samples collected throughout the 2005 Bering Sea trawl fishery, East Asian (29%), North Asian (29%), Pacific Northwest (19%) and Western Alaska (16%) stocks dominated the sample set with smaller contributions from Southwest Alaska (<2%) and the Upper/Middle Yukon River (5%) stocks. The estimates for the 2005 chum salmon bycatch sample set were similar to the 1994-1995 chum salmon bycatch estimates, suggesting consistency of the regional stock contributions across years. Analysis of temporal groupings within the groundfish B season revealed changes in stock composition during the course of the season. Whether the decreasing proportional contributions of Western Alaska and Upper/Middle Yukon stocks and increasing proportional contributions from Asia over time are due to temporal or spatial differences in the sample set are unknown.

This project evaluates data from coded wire tagging with that from parental based tagging to identify stock of origin for Chinook salmon landed in Washington state commercial troll fishery.

Allozyme variation was used to examine population genetic structure of adult chinook salmon, Oncorhynchus tshawytscha, collected between 1988 and 1993 from 22 spawning locations in Southeast Alaska and northern British Columbia. Thirty-five loci and two pairs of isoloci were variable, and of these, 25 loci and one pair of isoloci expressed the most abundant allele with a frequency of less than or equal to 0.95 in at least one collection. Aneighbor-joining (NJ) tree of genetic distances defined five regional groups: (1) King Salmon River (the only island collection), which has large allelic frequency differences from other populations in this study; (2) heterogeneous coastal populations from southern southeast Alaska; (3) transmountain collections from the Taku and Stikine Rivers on the eastern side of the coastal mountain range; (4) Chilkat River in northern Southeast Alaska; and (5) northern coastal Southeast Alaska, which consists of the Situk River and the Klukshu River, a tributary of the Alsek River. A second NJ tree that included collections from the Yukon River and British Columbia did not reveal any strong genetic similarity between Southeast Alaska and the Yukon River. The data suggest that Southeast Alaska may have been colonized from both northern and southern refugia following the last glaciation b?? a period of sufficient time to allow for isolation by distance to occur.