While it is known that the oceans around the Faroe Islands support an Atlantic salmon feeding ground, the relative use of this resource by different age classes and populations has, until now, been largely unexplored.
Atlantic samon. Photo Audun H. Rikardsen
A new publication indicate that the oceans around the Faroes host a predominantly multi-sea-winter feeding ground, and use of this resource varies across age classes and salmon from different regions. Furthermore, the new results suggest that multi-sea-winter fish from some areas preferentially migrate to the Faroes. Multi-sea-winter salmon are fish that have spent multiple winters at sea, whereas one-sea-winter salmon are those that return to the rivers after having spent one winter at sea.
Surprisingly, multi-sea-winter salmon from Ireland and the United Kingdom were as likely to occur around the Faroes as were multi-sea-winter salmon from more north-eastern regions. While one-sea winter salmon from Ireland and the United Kingdom as well as Southern Norway occurred in similar proportions around the Faroes, multi-sea-winter salmon from the north-eastern regions were virtually absent.
Variation in spatial resource use may help buffer salmon populations against localized negative changes in marine conditions via portfolio effects.
O'Sullivan, R.J., Ozerov, M., Bolstad, G.H., Gilbey, J., Jacobsen, J.A., Erkinaro, J., Rikardsen, A.H., Hindar, K. & Aykanat, T. 2022. Genetic stock identification reveals greater use of an oceanic feeding ground around the Faroe Islands by multi-sea winter Atlantic salmon, with variation in use across reporting groups. ICES Journal of Marine Science doi: 10.1093/icesjms/fsac182.