Stock Origins of Chinook Salmon in Incidental Catches by Groundfish Fisheries in the Eastern Bering Sea

Abstract

Abstract An estimated 386,946 chinook salmon Oncorhynchus tshawytscha were taken in incidental catches by foreign and joint-venture groundfish vessels operating in the Bering Sea portion of the U.S. exclusive economic zone, 1977–1986. Concern about the effect of incidental catches on the salmon fisheries of western Alaska provided the impetus for a study to determine the stock origins of chinook salmon in these catches. The proportions of regional (Asia, western Alaska, central Alaska, and southeast Alaska–British Columbia) and western Alaskan subregional (Yukon, Kuskokwim, and Bristol Bay) stocks of Chinook salmon in 1979, 1981, and 1982 samples collected by U.S. foreign fishery observers were estimated by scale pattern analysis. Estimated proportions ofthe regional stocks averaged 60% western Alaska, 17% central Alaska, 14% Asia, and 9% southeast Alaska-British Columbia. Western Alaska, which included Canadian Yukon fish, was the predominant regional stock in most age-group, time, and area strata. Stock...