Mating between anadromous and nonanadromous Atlantic salmon, Salmo salar

Abstract

Mating experiments were conducted to determine whether behavioural isolating mechanisms exist that would prevent interbreeding between anadromous and nonanadromous Atlantic salmon, Salmo salar. Males of both forms attempted to stimulate females of the other form to spawn and females responded by digging redds, spawning, and covering redds. Viable eggs were produced in both cases. These forms probably represent within-population phenotypic variation where they co-occur. Interbreeding can be expected if anadromous salmon are introduced into areas formerly occupied only by the nonanadromous form.