Siberian Whitefish (Coregonus lavaretus pidschian)
Siberian Whitefish (Coregonus lavaretus pidschian) – semi-anadromous fish, inhabits lakes and rivers, subspecies of sea whitefish, genus Coregonus. S. W. has a variety of forms with different numbers of gill rakers and behavior. Body length is 20–40 cm, rarely up to 50 cm; weight is up to 1.6 kg. Inhabits lakes and rivers of the European North and Siberia. Matures at 5–9 years. Spawning is in rivers, in autumn, and in early winter, on shingle. Fertility is 8,000–50,000 eggs, egg diameter 1.2 mm. Juvenile fish lives in rivers for 4–5 years and feeds on zooplankton; grown fish feeds on shellfish, maggots of chironomids, and crustaceous. S. W. grows with different speed, and especially quick growth is characteristic for S. W. in rivers (in the Ob). A valuable commercial species.