EASTERN MEDITERRANEAN - A MARINE DESERT

The Mediterranean Sea is considered by many as one of the less productive seas of the world. Due to geophysical and arid climatic conditions, the Eastern Mediterranean is the most oligotrophic part of that sea. After the operation of the Aswan Dam in 1965, the major nutrient contribution to this area was very considerably diminished. Several cruises and laboratory studies of the pelagic waters off the Israeli shore, indicated that the Eastern Mediterranean is comparable with the most oligotrophic parts of open oceans. The neritic waters, overlying the narrow continental shelf (10-20 km), were relatively much more productive than the pelagic waters, having in average three times the chlorophyll concentration and five times the primary production. However, even the neritic zone is very poor as compared to similar regions in the world. It is not surprising, therefore, that the total catch of marine fishes along the Israeli Coast is only few thousand tons annually.