Структура зоопланктонного сообщества в прибрежных водах Крыма (район Севастополя) и трофические отношения в пищевой цепи зоопланктон – мнемиопсис в 2004 – 2008 гг.

Mesozooplankton community and ctenophore Mnemiopsis leidyi population states were analyzed in coastal waters near Sevastopol in 2004 – 2008. Zooplankton annual dynamics and biodiversity were examined. Mean zooplankton annual abundance and biomass were described with two-peak curves with maximums in spring and autumn. During the research period Copepoda were dominating group and amounted about 70 % of forage zooplankton. In those years in both regions average annual abundance of Paracalanus parvus the species that was critically endangered after M. leidyi invasion to the Black Sea increased one order. While M. leidyi abundance decreased twice the mean annual abundance and biomass of forage zooplankton increased 3.5 times. Introduction and mass development of new alien species Oithona brevicornis resulted in substantial raise of Copepoda abundance in Sevastopol Bay to level of 1970-th.