C1 – The North East Atlantic

Pelagic fish stocks exhibit unique spatial and temporal distribution patterns related to their bioclimatic niche. Climate changes and the associated shifts in primary and secondary production have therefore impacted the distribution range, migratory habits and stock size of many marine fish species. However, few have been affected as dramatically as the straddling pelagic stocks. They provide an interesting showcase of extreme changes where climate induced fluctuations affect important biological processes such as reproductive success, population dynamics, migration patterns and interactions between fish populations. Due to their distribution patterns, these shared straddling stocks present multi-national management challenges and provide a good example for developing novel forecasting and early warning methodologies, and strategies to mitigate risks and utilize opportunities as well as a management plans enabling sustainable exploitation.

Geography

North East Atlantic includes the Barents Sea, the Norwegian Sea, West of Scotland, Faroese waters and Icelandic waters and the Deep basin area located between the North Sea, Norway, Iceland and Svalbard.

The average depth is 1800 m. Atlantic water flows northwards in the central and eastern part of the Norwegian Sea, along the continental shelf edge towards Svalbard, and also into the shelf south and west of Iceland. Polar water flows southward in the northwestern part of the Norwegian Sea with branches diverted into cyclonic gyres in the Greenland Sea and the Iceland Sea. This causes a strong gradient of decreasing temperature from east-to-west at latitudes north of 65 °N.

The Northeast Atlantic has a strong seasonal cycle in biological productivity, which is high in spring and summer but low in fall and winter.

Fisheries in the area

The areas support main important commercial fisheries, like mixed stock and multinational fisheries on herring, mackerel, capelin, blue whiting, sprat, anchovy and sardine. There is partly a direct fishery for herring, mackerel and blue whiting, although all species are mainly targeted at their respective overwintering or spawning areas outside the Norwegian Sea.