Scientific Journal of KubSAU

The article presents monitoring of the course and the beginning of new invasions due to the intensification of these processes in the basin of the Azov Sea of; investigation of the influence of the alien species upon the acceptor ecosystem. Methods. The material was collected at the monitoring transect in the Don River delta and in the surveys of the r/v “Professor Panov” in the Taganrog Bay, Sea of Azov. Standard hydrobiological methods of the data collection were used. Results. Penetration of three polychaete species was recorded; course of invasion of two of them was traced. Impact upon the acceptor ecosystem was researched. Preliminary species identifications using morphological characters were carried out; sources and the ways of the invasions are suggested. Conclusions. Estuary zone of the Sea of Azov (the Taganrog Bay) has a high invasion capacity. Of the three species penetrated into the Sea of Azov basin in 2013-2015, one (Aracia sp.) naturalized successfully, though didn’t affect much the ecosystem. On the contrary, polychaetes of the genus Marenzelleria are increasing rapidly their area; in two years, they became dominant along the considerable part of the water body. The invasion of Streblospio sp. is at its very beginning at the time