Assessment of commercial stocks and forecast for the catch of fish of Leuciscidae family in the Dnipro Reservoir for 2026

Purpose. To investigate the long-term dynamics of commercial catches of Leuciscidae in the Dnipro Reservoir and to determine sustainable catch limits as an aquatic bioresource. Methodology. The study was conducted in 2024–2025 at three commercial fishing areas of the Dnipro Reservoir (central part, lower part, Samara Bay), which differed in hydrology, ecology, and the level of human impact. Classical ichthyological methods were used. The study objects were members of the family Leuciscidae: common bream, chub, asp, roach, silver bream, blue bream, sabrefish, rudd, white-eye bream, vimba, and bleak. The analysis included species composition of commercial catches, age and size structure of fish populations, condition factors, catch dynamics over long-term series, and official commercial statistics (2014–2024). Findings. It was found that Leuciscidae species account for 54.1% of total catches in the Dnipro Reservoir cascade, with common bream, roach, and bleak being the main commercial species. Populations of these species are characterized by stable abundance and biomass. Based on biological and fishing parameters, fish stocks and catch limits for the Dnipro Reservoir in 2026 were calculated. Originality. For the first time in the Dnipro Reservoir, a comprehensive analysis of Leuciscidae commercial stocks was conducted, incorporating long-term data series, spatial-temporal population characteristics, and mortality coefficients. Differentiated fishing regimes for specific reservoir areas were proposed. Practical Value. The results allow optimization of fishery management, ensuring sustainable use of resources and biodiversity conservation, reducing the risk of stock depletion, and supporting the stability of commercial fishing. The proposed recommendations were used as the basis for establishing fish catch limits in the Dnipro Reservoir in 2026.