A recent research that makes use of historical data has discovered exceptional evidence in favor of the "safety in numbers" theory, according to which Pacific salmon living in bigger groups are less likely to be eaten by predators.
A sudden shift in climatic conditions in the North Atlantic approximately 800 years ago had a part in a drop in Atlantic salmon populations returning to rivers, according to research headed by the University of Southampton. Salmon stocks were further depleted as a result of subsequent human exploitation.