WGNAS is responsible for the annual assessment of the status of salmon stocks across the North Atlantic. NASCO asks WGNAS to provide catch advice, subsequently agreed by the Advisory Committee (ACOM), for both the Faroes and West Greenland fisheries.
Atlantic salmon can be caught in these distant water fisheries as well as under different jurisdictions in homewater fisheries. The distant water salmon fisheries, which take salmon originating in rivers of another Party, are regulated by NASCO.
WGNAS also develops advice on a wide range of other issues to support NASCO in exercising its responsibilities for the conservation, restoration, enhancement, and rational management of wild salmon in the North Atlantic.
In the Northeast Atlantic, salmon distribution extends from northern Portugal to northern Russia and Iceland, while in the Northwest Atlantic, the species ranges from northeastern USA (Connecticut) to northern Canada, and there are over 2000 rivers draining into the North Atlantic that support the fish.
Atlantic salmon spend their early lives in freshwater and then migrate long distances to sea to feed and grow before returning as maturing adults to spawn in freshwater, typically in their river of origin. Fisheries operate in two areas. One in the Norwegian Sea, where salmon from most Northeast Atlantic stocks mix in the autumn and winter, and a second to the west of Greenland, where salmon from both North America and some Northeast Atlantic stocks mix in their second summer at sea.
Environmental conditions in both freshwater and the sea have a marked effect on salmon stocks. A range of factors in freshwater, from contaminants to river obstructions, changing river flows to temperatures, are known to impact on stocks. Return rates of adult salmon (the percentage of juveniles migrating to sea that survive to return to freshwater) have also declined since the late 1980s. For many stocks, return rates are now at the lowest levels in the time-series, even after the closure of marine fisheries. This reduced survival is thought to reflect climatic factors and broad-scale changes in ocean ecosystems as well as factors in freshwater.