Composición de zooplancton superficial en zonas lisas y rugosas en la bahía de Coquimbo (noviembre 2001)

Abstract

The surface zooplankton abundances, sea surface temperature and wind speed in slick and rough surface areas were compared south of Coquimbo Bay on November 7, 8 and 9, 2001. The presence of rough and slick surfaces on the bay was influenced by the wind conditions during sampling hours, demonstrating that increasing the speed steadily over 6 m s-1 slick and rough areas disappeared, giving a ripple appearance to sea surface. On the first two days of study, thermal structure of slicks areas was different from the rough ones. On the last day, temperature was higher with no differences between both surfaces types, and greater depth of the mixed layer, due to increasing wind speed. The organisms captured were holoplanktonic crustaceans, meroplankton benthopelagic peracarids, fish larvae and eggs, gelatinous zooplankton and gastropod and bivalve mollusks. On the first two days of study, most of zooplanktonic groups had greater abundance in slick surfaces, with significant differences between slick and rough areas in the case of barnacle cypris larvae and the euphausiid Nyctiphanes simplex. It was concluded that surface zooplankton caught in Coquimbo Bay, tend to aggregate in rough or slick surfaces, depending on their adaptive characteristics and behaviour.