Current and predicted ecological impacts of climate change to Atlantic salmon freshwater productivity in the North Atlantic.
Post-glacial recolonization and multiple scales of secondary contact contribute to contemporary Atlantic salmon (Salmo salar) genomic variation in North America.
In northern environments, past ice ages isolated species like Atlantic salmon, shaping their genetic diversity.
Using advanced genomic techniques, researchers studied 5455 salmon across North America, from Labrador to Maine. They found three main genetic groups indicating salmon recolonized from two southern refuges after the last ice age.
These groups later interacted in the northern Gulf of St. Lawrence and even across the Atlantic.
Regions with European ancestry suggest additional historical interactions.
This study highlights how genomic tools reveal the complex history of wild salmon populations in North America.