Abstract

Megabenthic assemblages on the East Greenland continental slope at 75 N were surveyed at 8 locations between 190 and 2800 m depth using sea floor images taken vertically with a still camera. A total of 91 epibenthic species with 14447 indiv~duals were identified from 422 photographs depicting 297 n12 of the sea floor. Classification and ordination analysis defined 3 fauna1 zones that corresponded to different depth regions of the continental margin: shelf break, upper slope and lower slope. Megafaunal abundance was highest on the shelf (about 200 ind. m-2). In the other zones, the densities were distinctly lower (15 to 30 ind. m-2). Assemblages were frequently dominated by 1 or 2 species, such a s the polychaete Onuphis conchylega at the shelf break and the sponge Polymastia sp. at the lower slope The upper slope was characterized by a diverse octocoral-sponge assemblage. A statistical analysis of the correlation between megafaunal and environmental data at a 10 km scale (between stations) indicated that epibenthic distribution patterns were best explained by sea floor characteristics, whereas no evidence for a direct benthic-pelaglc coupling was found, irrespective of water depth. Additionally, the withln-station distribution of megabenthic organisms (100 m scale) was clearly affected by sea floor properties.

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