Dense aggregations of the ctenophore Beroe ovata (Eschscholtz) near the north-east shore of the Black Sea

During the autumn 1999, dense aggregations of the mediterranean ctenophore Beroe ovata has been recorded near the north-east shore of the Black Sea. t his specialised carnivorous animal feeds on other ctenophores, including Mn emiopsis. At the end of August-beginning of Septermer, the biomass of Beroe in the Golubaja Bay reached 130 g/m(2) of wet weight in average and 300 g/ m(2) in aggregations. This was resulted in the decrease of the biomass of M nemiopsis and, consequently, in the increase of the biomass of the mesosoop lankton and planktophagous fishes. If the high biomass of Beroe will take p lace in the future, the press of Mnemiopsis will probably decline, while bo th the biomass of the mesoplankton and the catches of economically importan t planktophagous fishes will increase.