Taxocene of polychaeta of the Laspi Bay water area (the Crimea, Black Sea)

The coastal zone of Laspi Bay (the Crimea, Black Sea) is attractive for the development of recreational activities. It can negatively affect the state of the bay ecosystem and adjacent waters. The aim of this study is to assess the current state of polychaetes inhabiting the loose soils of the littoral and sublittoral areas of Laspi Bay. In 2016–2019 the fauna of polychaetes was studied in the waters of Laspi Bay. Macrozoobenthos were collected on cruises 84, 86, 96, 108 aboard the research vessel Professor Vodyanitsky and in coastal expeditions. 89 samples were taken (19 deep-water, 70 coastal). 45 species of polychaetes were identified. The average abundance of Polychaeta was 2 368 ± 467 ind./m2. The average biomass was 44,128 ± 13,919 g/m2. Terebellides stroemii makes a significant contribution to the formation of these indicators. The ranked series by density index is headed by T. stroemii, Nephtys hombergii and Melinna palmata. The largest abundance of species is noted at a depth of 46 m where the soil is represented by sand and pebbles. The highest number is noted at depths of 93.5–98 m. Prionospio сirrifera makes the main contribution to the total number. The highest biomass is noted at depths of 53.5–58 m. T. stroemii makes the main contribution to the total biomass. In the Laspi Bay waters are recorded characteristic species – P. сirrifera and Micronephthys longicornis. They are found both in shallow waters and at great depths. Rare species found only at one station include 18 polychaete species. The results obtained give an idea of the taxonomic composition of polychaete worms in the waters of Laspi Bay and can be useful for further monitoring of this area.