The expedition is being carried out on its own vessel, which is based near the traditional monitoring point - the village of Igrim in the Berezovsky district of Yugra. Scientific work on accounting of upwelling schools of valuable commercial fish in the Northern Sosva will last two months.
During this time, specialists will conduct control catches, determine the size-age and species composition of the migrating ichthyofauna, and perform biological analysis. To assess the amount of fish, its concentration and distribution, scientists use a modern hydroacoustic complex. With the help of echo sounding, the necessary data on the number of fish rising to spawn and wintering grounds will be obtained.
The Northern Sosva is the largest of the Ural tributaries of the Lower Ob and the main spawning river of the Lower Ob basin, where most whitefish reproduce: peled, broad whitefish, whitefish-pyzhyan, tugun and nelma. Geographically, the river belongs to the Polar and Subpolar Urals, the area along its banks is practically untouched by humans. Monitoring the state of spawning stocks of whitefish in the Northern Sosva basin has been conducted since the late 1970s.
Comprehensive scientific research is of great importance for fisheries, the results obtained will form the basis for forecasting the permissible catch for 2026.
Press service of VNIRO