Congratulations to Yann Czorlich and co-authors with publishing important results on Atlantic salmon in prestigious Science!
Atlantic salmon. Photo Eva B. Thorstad
In this new Science paper, Yann Czorlich and co-authors identify rapid evolution in Atlantic salmon life-history induced by direct and indirect effects of fishing.
They identify the drivers of evolution toward earlier age at maturity in Atlantic salmon via two types of fisheries-induced evolution acting in opposing directions.
- An indirect effect was linked with commercial harvest of a salmon prey species, capelin, in the Barents Sea (selection against late maturation). In years of low capelin abundance, fewer salmon survive multiple years in the ocean.
- A direct effect was due to temporal changes in net fishing pressure in the river (selection against early maturation).
One of the uses of North Atlantic capelin harvest is for fish meal and oil in aquaculture food, so this is also an indirect path by which Atlantic salmon aquaculture may influence wild salmon populations.
Identifying the evolutionary impacts of human activities is challenging because of lack of temporal data and limited knowledge of the genetic basis of most traits. This is therefore an important publication for understanding human activities as drivers of evolution.
Czorlich, Y., Aykanat, T., Erkinaro, J., Orell, P. & Primmer, C.R. 2022. Rapid evolution in salmon life history induced by direct and indirect effects of fishing. Science 10.1126/science.abg5980 https://www.science.org/doi/10.1126/science.abg5980