Report of the Working Group on International Deep Pelagic Ecosystem Surveys - 1 (WGIDEEPS)

The Working Group on International Deep Pelagic Ecosystem Surveys (WGIDEEPS) met at ICES HQ in Copenhagen from 13-15 February 2018. The meeting, chaired by Kristján Kristinsson, was attended by six participants from Germany, Iceland, Norway and Russia. At the meeting the group planned the redfish survey in the Irminger Sea in June/July 2018.
Prior to the meeting, the Icelandic delegation informed group members that Ice-land will not participate in the survey in June/July 2018. To cover the whole distribution area of pelagic redfish in the Irminger Sea a minimum three vessels are needed. The scope of the survey had to be altered and will be carried out in same manner as in 2015. The emphasis is on covering the main distribution area of red-fish in the north and south-north area but omit important geographical areas of pelagic redfish in the southwestern area.
The detailed planning of the international trawl/acoustic survey on pelagic redfish in the Irminger Sea and adjacent waters in June/July 2018 has been agreed by all participating countries. Two vessels from Germany and Russia will participate in the survey and operate within an area of around 200 000 square nautical miles (NM2) in the Irminger Sea to estimate the abundance and biomass of pelagic redfish (Sebastes mentella). In the depth zone that can be surveyed by hydroacoustic measurements, i.e. shallower than the deep-scattering layer (DSL; down to about 350 m), hydroacoustic measurements and identification trawls will be carried out. Within and below the DSL (down to about 950 m), redfish abundance will be estimated by trawls. The trawl method applied is the same as in the 2009-2015 surveys and is line with the recommendation from ICES to study separately the stocks shallower and deeper than 500 m. As in past surveys, biological data will be collected from the redfish caught in the pelagic trawls, and hydrographical measurements will be taken on regular stations on the survey tracks.
The future of the survey in the Irminger Sea was discussed during the meeting. The withdrawal of Iceland from the international redfish survey in the Irminger Sea and adjacent waters is very unfortunate. No alternatives that could be arranged for compensating the corresponding loss of survey coverage at the time being. The Group is concerned with the decreased data quality and higher uncertainty in the derived dataseries and consequently the advice on the stock status. The group also encourages relevant delegates and institutes to discuss the priority and the future of the survey in the Irminger Sea and adjacent waters.