The modern Ichthyofauna of the Moscow River

Abstract

Based on the results of ichthyological monitoring, the structure of the catches of fixed, ring and smooth nets, as well as the fry seine for sections of the upper and lower reaches of the Moscow River in 2010–2018 is presented. There were no significant changes in the composition of the ichthyofauna of the Moscow River above the capital compared to the 80–90s of the twentieth century. In the middle and lower reaches of the river, limnophile fish dominate in number and biomass. The share of invasive and previously not accounted for in catches of species in the fish population of the Moscow River by the 20s of the XXI century is already 38 % (17 species), although the occurrence in catches does not exceed 1.3 %. The aim of the work is to analyze the dynamics of the ichthyofauna and determine the fish productivity of various sections of the Moscow River according to the results of ichthyological monitoring of the freshwater fish laboratory of the VNIRO Federal State Budgetary Institution for 2010–2018. Methods used: the collection of ichthyological material was carried out by active and passive net fishing gear. The estimation of the number and biomass of fish was carried out according to traditional methods of direct accounting using smooth and ring nets, as well as a fry seine. Novelty: for the first time during the period of ichthyological research, information is provided on the structure of catches for various sections of the Moscow River according to the hydrological regime. The indicators of fish biomass calculated on the basis of fishing with various tools are presented. The presence of new alien species in the ichthyofauna of the Moscow River at the present stage of its ecosystem existence has been revealed. Practical significance: the results of the work allow us to assess the dynamics of the composition of the fish population and the structure of ichthyocenoses for different sections of the river according to the hydrological regime. The estimation of the number and biomass of fish is necessary to predict the recommended catch of the most significant objects of amateur fishing. Assessment of the state of populations of fish species uncharacteristic for the basin of the Moscow River makes it possible to understand the mechanism of invasive processes and the degree of adaptation of intruders in the conditions of the ecosystem of the Moscow River.