| Summary: | The Workshop on Redfish and Oceanographic Conditions (WKREDOCE) was established as a response to a request for advice from NEAFC (Northeast Atlantic Fisheries Commission) to ICES “to analyse the distribution and abundance of pelagic redfish (Sebastes mentella) in the Irminger Sea and adjacent waters in relation to environmen-tal changes” (see Section 1.4). Prior meetings in September of 2011 and March 2012 identified possible data sources, set the objectives to address the ToR (Section 1.5) and reviewed two preliminary analyses (ICES 2011a, ICES 2012a). The present meeting, WKREDOCE3, attended by ten participants (four by corre-spondence) from Canada, Germany, Iceland, Netherlands and Russia to finalize and review three analyses done intersessionally. A seasonal study based on commercial data assumes that movements of the fleets reflect movement of the fish although other factors likely also affect fleet dynamics. In April-July, densest concentrations of the redfish are found primarily in the northern part of international waters of the Irminger Sea and the adjacent EEZs of Iceland and Greenland. They comprise primarily large individuals. Hydrographic conditions in the 100-800 m layer advected by the Irminger Current are: temperature, 4.3-7.7 °С; salinity, 34.9-35.2; vertical gradient of potential density under 0.44 kg/m3 km1 and 4°С isotherm depth ranging from 550 to 1350 m. The densest concentrations of the redfish in Aug.-Sept. occur in the subsurface layer of more southern areas, the Irminger Basin and the Northwest Atlantic Mid-Ocean Channel, and comprise small-er individuals. This concentration occurs in modified Atlantic waters associated with a combination of relatively reduced average temperature (3.4-6.7°С) and salinity (34.8-35.0) in 100-800 m layer, more pronounced density stratification (the potential density gradient is 0.23-0. 65 kg/m3 km1) and reduced upper layer of warm waters (4 °С isotherm < 850 m). Interannually, spatial distribution of S. mentella in the Irminger Sea, mainly in waters ...
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