Ecological and physiological characteristics of the ctenophore Beroe ovatain the coastal waters of the Black Sea: Abundance, biomass, size distribution, behavior, feeding, and metabolism

Basic ecological and physiological characteristics of the new invader to th e Black Sea-ctenophore Beroe ovata are examined. The studies were carried o ut in September-October 1999 in Golubaya Bay and adjacent waters (northeast ern part of the Black Sea off Gelendzhik). Abundance, biomass, and size str ucture of the populations of B. ovata and also its potential prey Mnemiopsi s leidyi were identified with the use of diving methods. Dry to wet weight ratios and carbon contents in the ctenophores' bodies were measured. Parame ters of oxygen exchange and quantitative regularities of the Beroe feeding were studied. Observations on the feeding behavior of the ctenophores in th e sea and laboratory were carried out using an underwater video camera. Dat a on the biology and interaction of the invaders B. ovata and M. leidyi wer e analyzed. Preliminary estimates of the probable impact of the newcomer on the M. leidyi population were made.