Oceanic redfish (Sebastes mentella) in the Irminger Sea and adjacent waters |
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J. Magnusson and J.V. Magnusson |
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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 separate stock. This stock distinguishes itself by a different appearance, i.e. the heavy infestation by the parasitic copepod Sphyrionlumpi and by other biological measures such as size, weight and maturity. The fishery of this stock was commenced in 1982 contributing an average annual catch of approximately. 63,000 tonnes. Females aggregate in the eastern part of the Irminger Sea for the extrusion of larvae, at depths of 300 to 400 m and in temperatures from 5.0°C to 6.5ºC during March to May. Summer and autumn aggregations are observed in the western part of the Irminger Sea in the uppermost 250m, in temperatures from 4ºC to 5.5ºC. A hypothesis of the life-cycle of the oceanic redfish is presented. The acoustic estimation of the adult stock carried out in 1992 indicated a stock size of about 2 million tonnes. |
Keywords: Stock identification, distribution, extrusion of larvae, biological information, infestation by Sphyrion lumpi, life-cycle, assessment, Irminger Sea. |
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Sci. Mar. 59(3-4) : 241-254 |
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