Current Changes in Fish Population in Large Rivers of Russia in the European Northeast

摘要

The current changes in fish population in waterbodies of Russia in the European Northeast reflect a real appearance of new fish species in communities as well as an active expansion of fish species which were few earlier. Six new fish species not recorded previously have been identified in the Pechora River basin. At least six fish species have appeared in the Northern Dvina basin, which has been connected to the Volga-Kama basin through artificial channels for almost 200 years (invasion corridors for fish migration). Appearance of new commercial fish species in northern river, ecosystems is possible, but not their naturalization (because of the high catch ratio). Successful immigration of small noncommercial fish species with high adaptive potential is much more possible. Thus, in the very near future, we may expect a penetration of some species of bullhead widespread in freshwater waterbodies of the Volga-Kama basin.