Determination of population structure and stock composition of chum salmon (Oncorhynchus keta) in Russia determined with microsatellites

In Asia, there are two distinct types of chum salmon (Oncorhynchus keta Walbaum). The early-maturing or “summer” chum salmon generally returns to spawn from June through August in streams bordering Kamchatka, the Sea of Okhotsk, the east coast of Sakhalin Island, and the Amur River. Later-maturing or “autumn” chum salmon generally return to spawn from September through November in streams in Japan, the southern Kuril Islands, the west coast of Sahkalin Island, and the Amur River (Sano, 1966). In general, summer chum salmon spawn in areas where egg incubation occurs in subsurface stream flow, whereas autumn chum salmon spawn in areas of groundwater upwelling (Volobuyev et al., 1990). In major river drainages, autumn chum salmon generally migrate further up the drainage to spawn than do summer chum salmon, and are larger, younger, and more fecund than the summer-run fish (Sano, 1966). Determination of the origin of salmon in mixed-stock fisheries is important for effective management. For chum salmon in Asia, scale pattern variation has provided a technique Determination of population structure and stock composition of chum salmon (Oncorhynchus keta) in Russia determined with microsatellites