The role of interannual environmental variations in the geographic range of spawning and feeding concentrations of redfish Sebastes mentella in the Irminger Sea

• Published in: ICES Journal of Marine Science
• Main Author: Pedchenko, Andrey P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press (OUP) 2005
• Subjects: North Atlantic; Sebastes mentella
• Online Access: http://dx.doi.org/10.1016/j.icesjms.2005.08.004; http://academic.oup.com/icesjms/article-pdf/62/7/1501/29125482/62-7-1501.pdf

Abstract The Irminger Sea is occupied by the most abundant population of the redfish, Sebastes mentella, in the North Atlantic. Results of Russian and international surveys of redfish in the Irminger Sea between 1982 and 2003 are summarized here. Interannual variations in redfish spatial distribution and oceanographic conditions are also analysed. Distribution patterns of spawning and feeding concentrations of redfish are established, and the role of oceanographic factors in the formation of concentrations and in the migrations of redfish are shown. The habitat of the mature redfish population in pelagic waters is confined within the Sub-polar cyclonic Gyre. Redfish spawning grounds extend along the western slope of the Reykjanes Ridge in the areas of intensive rise of intermediate waters. Seasonal variation in water temperature above the ridge slopes is one of the factors causing feeding redfish to migrate westwards, to the central area of the Sub-polar Gyre. Atlantic Water advection, intensified by the Irminger Sea, and water temperature increase in the upper 200-m layer in the second half of the 1990s produced a considerable shift of commercial concentrations of feeding redfish from their usual grounds westwards, to the NAFO Regulatory area.