Avoidance of hydrodynamically mixed environments by Mnemiopsis leidyi (Ctenophora: Lobata) in open-sea populations from Patagonia, Argentina

摘要: Biomass distributions of the ctenophore, Mnemiopsis leidyi, were collected during a week-long survey program in tidal front along Patagonian shelf December 1989. Average ctenophore biomass concentrations varied significantly north–south gradient and stratified compared to unstratified waters. The relative vertical distribution M. leidyi appeared be constrained by surface levels shear. Vertical highly variable at low shear (<4 s−1) surface, but higher ctenophores occurred deeper water column where lower. These results indicate that physical conditions are important factors influencing summer months.