The distribution of Decapoda (Crustacea) in the open ocean and near-bottom over an adjacent slope in the northern North-east Atlantic Ocean during autumn 1979

The vertical distribution of Decapoda (Crustacea) at deep-water stations in the Rockall Trough and the Porcupine Seabight is discussed and compared to the near-bottom distribution of Decapoda on the continental slope of the Seabight. The vertical distribution of some species is unaffected by the shallowing of the sea floor in the slope area. Other species are found in much higher concentrations near-bottom over the slope than at similar depths at the adjacent deep-water stations and at least one species extends its lower vertical range. It is suggested that the increased food availability near-bottom may be the principal factor influencing aggregation.