OCEANIC REDFISH (SEBASTES-MENTELLA) IN THE IRMINGER-SEA AND ADJACENT WATERS

Information is given on a large pelagic stock of adult redfish in the Irminger Sea. Although this oceanic redfish is considered to belong to the species Sebastes mentella Travin, 1951, it is defined as a separa te stock. This stock distinguishes itself by a different appearance, i .e. the heavy infestation by the parasitic copepod Sphyrion lumpi and by other biological measures such as size, weight and maturity. The fi shery of this stock was commenced in 1982 contributing an average annu al catch of approximately. 63,000 tonnes. Females aggregate in the eas tern part of the Irminger Sea for the extrusion of larvae, at depths o f 300 to 400 m and in temperatures from 5.0 degrees C to 6.5 degrees C during March to May. Summer and autumn aggregations are observed in t he western part of the Irminger Sea in the uppermost 250 m, in tempera tures from 4 degrees C to 5.5 degrees C. A hypothesis of the life-cycl e of the oceanic redfish is presented. The acoustic estimation of the adult stock carried out in 1992 indicated a stock size of about 2 mill ion tonnes.