Genetic study in Finaland finds early summer fishing can have an evolutionary impact, resulting in smaller salmon

Atlantic salmon are caught by fisheries when the fish are migrating to spawn. A new study led by the University of Helsinki explored how salmon caught at different times during their spawning migration differ from each other genetically. The study on wild salmon in the northern Baltic Sea revealed that especially in the early part of the fishing season, fishing strongly targets salmon carrying a "large salmon genetic variant." The variant guides Atlantic salmon to grow large and to mature at an older age, which is an important trait for the fishing and viability of salmon stocks.The findings are published in the journal Evolutionary Applications.Genetic analyses on thousands of wild salmon caught between 1928 and 2020 by fisheries from the northern Baltic Sea region showed that regardless of the year, fishers caught salmon with the "large salmon variant" more often in the early than late fishing season."This finding suggests that the timing of fishing may cause evolutionary ...