Bondarenko O. Ecology of polychaetes in the northwestern Black Sea

The work is dedicated to the study of species composition and rules governing spatial distribution of polychaetes of macro-, pseudo- and eumeiobenthos in the northwestern Black Sea (NWBS). At present the NWBS, polychaete fauna account for 54 representatives, 14 of which are eumeiobenthos representatives. The most diverse fauna is in Karkinitsky and Egorlitsky bays. There was a mass settlement of juvenile Prionospio cirrifera in the Odessa coastal area, and of Alitta succinea and Polydora cornuta seaward of the Danube. A recruitment of P. cirrifera and Melinna palmata populations which were degraded in 1980-1990 was registered. Marked seasonal dynamics of juvenile polychaete abundance have been revealed. It has been established that the substrate type determines the local diversity of polychaetes of macro-, pseudo- and eumeiobenthos, and quantitative parameters of macro- and eumeiobenhos. Salinity has an influence on the variability of a diversity in adult individuals; temperature - on that of biomass of the latter and on juvenile diversity. It has been noted that P. cornuta larvae when transferring to the benthal, actively select the places for settlement of adult individuals of their species. The settlement of P. cirrifera and Capitella capitata species is not tied with adult individual settlement.