Characterization of the zooplankton community of the western part of the Proletarsky Reservoir in the spring season of 2021–2022

The Proletarsky Reservoir located in the Kuma–Manych Depression is a water body that is highly important for the fisheries in the Southern Russia. Its western part is the most economically valuable, which necessitates the investigation of its zooplankton serving as a food source for the larvae and planktivorous fish. This work presents the results of investigation of the zooplankton community in this area during fish spawning campaign in the spring seasons of 2021–2022. In spring, the zooplankton was represented by 4 groups of organisms (30 species), which include rotifers, copepods, cladocerans, and meroplankton. Among them, the copepods were the most diverse, with the species of Cyclopoida suborder being the most prevalent. The rotifers were the most abundant, comprising 67 % of the total zooplankton abundance. The cladocerans comprised the major part of the zooplankton biomass; their share in the total biomass consistently remained at 79 %. The total biomass of the zooplankton exceeded 300 mg/m3, which is sufficient to provide the planktivorous fish species and their larvae with a food source.