Population Structure of Chum Salmon of the Russian Far East: Biogeographic Classification, Genetic Differentiation, and Ecogeographic Units of the Species

The chum salmon, Oncorhynchus keta Walbaum, spawning in rivers and lakes of the Far East, is divided into ecogeographic units (EGUs) based on zoogeographic zoning of the species range, biological features of groups that take into account spawning areas and ecological forms (ecotypes), and genetic differences between them. Each EGU has definite geographical boundaries and can include several spawning populations of chum salmon from different water bodies within these boundaries. Populations of chum salmon from different EGUs have significant genetic differences between each other. Ecogeographic units are important elements of the intraspecific structure. They can also be considered as basic management units of chum salmon, which should be taken into account when developing a strategy for managing stocks of aquatic biological resources. In particular, in the process of artificial reproduction of this species, transfer of fertilized eggs between populations from different EGUs is highly undesirable.