MEGABENTHIC COMMMUNITIES IN THE WATERS AROUND SVALBARD

Composition and distribution of megabenthic communities around Svalbar d were investigated in June/July 1991 with 20 Agassiz trawl and 5 bott om trawl hauls in depths between 100 and 2100 m. About 370 species, ra nging from sponges to fish, were identified in the catches. Species nu mbers per station ranged from 21 to 86. Brittle stars, such as Ophiaca ntha bidentata, Ophiura sarsi and Ophiocten sericeum, were most import ant in terms of constancy and relative abundance in the catches. Other prominent faunal elements were eunephthyid alcyonarians, bivalves, sh rimps, sea stars and fish (Gadidae, Zoarcidae, Cottidae). Multivariate analyses of the species and environmental data sets showed that the s patial distribution of the megabenthos was characterized by a pronounc ed depth zonation: abyssal, bathyal, off-shore shelf and fjordic commu nities were discriminated. However, a gradient in sediment properties, especially the organic carbon content, seemed to superimpose on the b athymetric pattern. Both main factors are interpreted as proxies of th e average food availability, which is, hence, suggested to have the st rongest influence in structuring megabenthic communities off Svalbard.