GAMMARUS (CRUSTACEA, AMPHIPODA) FROM SVALBARDAND FRANZ-JOSEF-LAND - DISTRIBUTION AND DENSITY

The distribution of Gammarus oceanicus, G. setosus and G. wilkitzkii w as studied over the period 1981-1991 in the coastal zone of the Svalba rd and Franz Josef Land archipelagos. The occurrence of G. oceanicus i s connected with the presence of Atlantic waters and favourable ice co nditions. In the area investigated this species was found on the west and north coasts of the island Vestspitsbergen only. G. setosus occurs in most of the investigated localities, being most abundant in the in ner fjord basins and other sheltered waters. G. wilkitzkii occurs typi cally in ice-associated plankton, but occurs in the intertidal zone am ong algae at Franz Josef Land. The maximum densities of gammarids atta ined 2000 ind/m2 at maximum, the mean being about 300 ind/m2, the typi cal site being large stones in sheltered bays at low water.