The Migratory Biology and Feeding Habits of Downstream-Migrating Juvenile Chum Salmon Oncorhynchus keta in the Amur River of Northeast China

The size of chum salmon juveniles is crucial to their survival. In order understand the population status and migration patterns juvenile in waters Amur River China, this study investigated resources basic biological characteristics Ussuri China. results showed that average catch per unit effort (CPUE) river margins was 0.140 ind·10−3 m3 for 0.255 River. Chum migrate downstream, mainly mid-May early May River, no fish caught rivers after June. Most migrated when water between 10 14 °C. FL (fork length) BW (body weight) samples were 37.1 ± 2.9 mm 0.42 0.09 g, respectively, while samples’ 34.9 3.7 0.36 0.08 respectively. empty stomach rate zero, prey category composed fish, aquatic insects, copepods, cladocerans, which Ephemeroptera had largest percentage index relative importance (IRI%), with a value 58.45%. downstream-migrating similar those some other rivers, CPUE varies depending on conditions.