An improved supra- and epibenthic sledge for catching Peracarida (Crustacea, Malacostraca)

Abstract

A new type of epibenthic sledge is presented, which possesses an additional supranet above the epinet. Both nets are closed by an opening/closing device in the water column. The new construction allows a selective catch ofhigher suprafauna, which swims 1–1.33m above the seafloor, and a good discrimination between real suprafauna and epifauna. In total, 79581 Peracarida were sampled at 8 stations at about 75°N and 12°W, off Greenland. Of these, Isopoda were usually the most abundant group in the epinet, Amphipoda in the supranet. At the stations where suprafauna was abundant, the numbers of Mysidacea were usually higher in the epinet than in the supranet, probably due to differences in food supply, i.e. the enrichment of food in the benthic boundary layer.