Biochemical Genetic Survey and Stock Identification of Chum Salmon (Oncorhynchus keta) in British Columbia

Abstract

We examined genetic variability using electrophoretic analysis of 83 chum salmon (Oncorhynchus keta) stocks in British Columbia and used regional differences in genotypic frequencies of seven polymorphic loci to estimate stock compositions in a number of commercial and experimental test fisheries. Chum salmon from five regions could be discriminated: Queen Charlotte islands, north and central coast, west coast of Vancouver Island, the Fraser River and its tributaries, and the south coast (rivers draining into Johnstone Strait and the Strait of Georgia). Allelic frequencies from 33 stocks were generally stable over a period of 2 yr or more. South coast chum salmon was the dominant run migrating through upper Johnstone Strait in October 1982–85. The genetic method of stock identification provided managers with the relative proportions of Fraser River and other groups of chum salmon in a number of fisheries and allowed managers to regulate more effectively the exploitation rate of Fraser River chum salmon.