The current state of aquatic biological resources and fisheries in the lower Dniestr and Dniestrovskiy liman

Abstract

The fish species composition and structural characteristics of the ichthyofauna of the Lower Dniester and Dniesterovskiyliman are presented. In total 79 species of fish from 16 orders, 24 families, 61 genera were observed in 2006–2018.The largest number of species in two orders: Cypriniformes and Perciformes (40.5 and 25.3%, respectively); largest number of genera and species in families: Cyprinidae – 22 genera and 29 species, Gobiidae – 7 genera and 13 species,and Percidae – 5 genera and 5 species. Ichthyofauna of Lower Dniester and Dniesterovskiy liman is represented byfour main faunal complexes. The dominant complex is the Ponto-Caspian, combining brackish and marine fish species.Ichthyofauna of the Lower Dniester is formed mainly by freshwater (55.7% of the total number of identified species)and brackish-water fish (26.6%). Most of species (77.2%) are demersal and bottom dwelling, phytophiles (34.2%)and lithophiles (22.8%), benthophages and carnivores. The remaining groups are represented by fewer species.The analysis of the current state of aquatic bioresources are presented. From 16 to 28 species of fish are recorded inthe commercial catches of the Lower Dniester and Dniestrovskiy liman. The dynamics of catches of the main commercialfish species are presented according to official statistics. Significant increase in the catch of gibel carp, an increase inthe catch of common carp? roach and common bream, and a decrease in the number of populations of predatory fishspecies was observed. The total catch of aquatic biological resources from 2013 to 2017 increased sharply from 547.9 to2344.3 tons per year. Gibel carp Carassius gibelio (Bloch, 1782) is the dominant fish species in the Lower Dniester.The catches of this species increased significantly (up to 1967.8 tons). The age and sex composition, as well as the sizemasscharacteristics of the main commercial species are presented. A decrease in the age composition of the populationsof the main commercial fish species as a result of an increase in the intensity of fishing was observed. The commercialfish mortality rates and stocks of the main commercial species are presented. The stock of gibel carp is set at 5,000–6,000 tons, bream – 630 tons, roach – about 150-200 tons, common carp about 200–250 tons, pikeperch – 20–25 tons.Forecasts of the allowable catch of the main commercial fish species of the Lower Dniester are presented.