TAXONOMIC AND ECO-FAUNISTIC FEATURES OF THE NOWADAYS FISH FAUNA OF THE GULF OF ODESA, THE DNIESTER MOUTH FOREFRONT NEAR-SHORES AND COASTAL WATERS OF THE SNAKE (ZMIINYI) ISLAND

Abstract

Introduction (relevance). The sea ecosystem investigations and investigations of its individual components, in particular, coastal ichthyocenoses, remain relevant. It’s very important for the development and implementation of measures for the conservation and rational use of fish resources of the entire Black Sea.The aim of this work is ichthyofauna investigations of the coastal areas in the northwestern part of the Black Sea. Main results. The inventory of the fish fauna species composition in the Gulf of Odessa, the Dniester mouth forefront near-shores and Snake Island coastal waters (North-Western Black Sea) is provided. In the results of the long-term ichthyological studies we registered: 80 fish species (from 63 genera, 37 families, 27 orders) in the Gulf of Odessa, 64 species (from 56 genera, 35 families, 27 orders) in the Dniester mouth forefront near-shores, and 76 species (from 63 genera, 40 families, 27 orders) in Snake Island coastal waters. The structures of fish assemblages are present in the comparative aspect. The long-term changes of the fish fauna species composition are discussed. Also we discussed the changes in the fish habitat conditions in the North-Western Black Sea, causes of the new species appearances in the study area, the effects of the invasive species on the native fauna.Suggestions (Conclusions). In total 98 species (from 79 genera, 42 families, 28 orders) of marine, brackish-water, anadromous and freshwater fish were identified. The number of fish species may increase in the case of the penetration and dispersal of new invading species, or transit of the freshwater fish into the coastal sea areas. The value of similarity of the ichthyofauna of the Odessa Bay and the Dniester mouth forefront at the species level is 80.6 %, of the Dniester coastal area and the coastal waters of the Snake Island – 77.1 %, of the Odessa Bay and coastal waters of Snake Island – 76.9 %. Key words: fish fauna; Gulf of Odessa; Dniester River mouth; Snake (Zmiinyi) Island.