Continuous deep-scattering layers have been observed in the Irminger S
ea for many years. Acoustic observations were carried out during the O
-group surveys in the Irminger Sea, in August, in the years 1993-1995.
In this paper, the distribution and relative abundance of component o
rganisms based on acoustic values is presented. The layers are observe
d within the range of 400-500 m to 700-800 m depth. Diurnal migrations
of a part of the layers are described. The layers consist of a great
variety of organisms. The known components are mainly diverse species
of fish of which an overview is given. Regional differences are outlin
ed. (C) 1996 The Fisheries Society of the British Isles