Taylor and Francis Group, Marine Biology Research, 6(7), p. 525-539, 2011
DOI: 10.1080/17451000.2010.535834
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Megafauna play an important role in benthic ecosystems and contribute significantly to benthic biomass in the Arctic. Their distribution is mostly studied by towed cameras. Here, we compare the megafauna from two sites located at a different distance from the Kongsfjord: one station at the very entrance to the fjord, another farther on the outer shelf. Although they are only located 25km apart and at comparable depth, there were significant differences in their species composition. While the inshore station was characterised by shrimps (2.57 ± 2.18 ind.m-2) and brittlestars (3.21± 3.21 ind.m-2), the offshore site harboured even higher brittlestar densities (15.23 ± 9.32 ind. m-2) and high numbers of the sea urchin Strongylocentrotus pallidus (1.23 ± 1.09 ind.m-2). Phytodetrital concentrations of the upper sediment centimetres were significantly higher inshore than offshore. At a smaller scale, there were also differences in the composition of different transect sections. Several taxa were characterised by a patchy distribution along transects. We conclude that these differences were caused primarily by habitat characteristics. The seafloor inshore was characterised by glacial soft sediments, whereas the station offshore harboured large quantities of stones. Although the use of a new web-2.0-based tool, BIIGLE (http://www.BIIGLE.de), allowed us to analyse more images (~90) than could have been achieved by hand, taxon area curves indicated that the number of images analysed was not sufficient to capture the species inventory fully. New automated image analysis tools would enable a rapid analysis of larger quantities of camera footage.