Scientists sought to obtain reliable data on how aquatic biological resources are distributed, how numerous they are, and what their biological characteristics are during the summer feeding season.
Ichthyological material was collected around the clock, both day and night, using fixed and smooth nets. This approach helped to take into account the diurnal migration rhythms of the river's inhabitants. For each captured individual, the species was determined using modern taxonomic keys and size and weight indicators were recorded.
Bream made up the majority of catches in terms of abundance and biomass, while other notable species included bream, chehon, carp, and asp. An important result of the expedition was the fixation of juvenile sterlet and shemaiah — these fish are classified as rare species and are included in the Red Book of the Russian Federation.
The collected data will help in the development of regulations on fisheries regulation, as well as documents with information on endangered fish species.
VNIRO Press Service
