Composition and abundance of zooplankton of the eastern Mediterranean Sea

Results of investigations on the composition and quantitative distribution of zooplankton of the eastern Mediterranean Sea were reviewed for the perio d 1950-1980. The studies reviewed comprise more than 250 stations (with abo ut 2000 samples) mainly from the expeditions carried out by the Institute o f Biology of the Southern Seas (IBSS), attached to the National Academy of Science of the Ukraine. Many of these stations are located in poorly studie d deep-water regions. For comparison purposes data from the literature on t he coastal regions were also used. During these studies, >30 new species of zooplankton were identified from t he eastern Mediterranean. The abundances of zooplankton from different loca tions in this region were evaluated. A trend was observed whereby the quant ity of zooplankton was seen to decrease from the west to the east and from the north to the south. Such events correspond to an impoverishment of nutr ients in the water. The coastal regions, desalinized by river inflows, were poorer than the dee p-water regions with respect to species number, but richer in abundance.