Ichthyological observations and length-based indicator (lbi) assessment of fish populations in the Rybinsk reservoir in 2024

The work is devoted to the expedition of the R/V «Vladimir Uskov» in 2024, which was aimed at assessing the status of commercial and mass non-commercial fish species, as well as comparison with the results of 2023. In addition, for the first time a modern method of catch analysis LBI (Length-based indicators), based on the analysis of fish size series, was used. The study notes that 16 fish species of five families were recorded in trawl catches and set nets in the Rybinsk Reservoir. As a result, the biological status of biomass and abundance of commercial fish in 2024 in the Rybinsk reservoir remains at a normal level for sustainable and precautionary fishing. Thus, the biomass and abundance of bream, pike, zander, blue bream, roach, white bream, sabrefish, Volga zander and ruff were higher in 2024 than in 2023. The populations of pike, catfish and perch remain small. Due to their small numbers, the commercial importance of ide, burbot, tench and crucian carp is still low, as evidenced by their rare catches. It is necessary to note positive efforts to release sterlet from fish hatcheries, whose juveniles were observed in trawling at Koprino station.