Species composition and pattern of fish distribution in Siberia

At the end of the first half of the 20th century, 61 species and subspecies of fish, including one invader (bleak Alburnus alburnus) and 17 species—endemics of Baikal—were reported for Siberia (Berg, 1933, 1949). At the present time, in rivers, lakes, and reservoirs of Siberia, 96 fish species and subspecies are described, of which 80 are aboriginal and 16 are invaders; 33 species are endemics of Baikal. Each landscapegeographic zone of Siberia has its specific ichthyofauna: in rivers and lakes of the south of Siberia, species of boreal piedmont complex dominate; in water bodies of the steppe, forest-steppe, taiga, and southern parts of the forest-steppe zone boreal plain dominates; in the zone of tundra, arctic freshwater dominates; and in Baikal, the most part (35) of species belongs to the Baikal autochtonous complex. Most researchers, as before, distinguish in Siberia two ichthyogeographic sites—West Siberian and East Siberian—that enter the Arctic Province of the Circumpolar subregion of the Holarctic region. Baikal is considered in the rank of the suboblast of the Holarctic.