Life History and Timing of Migrations and Spawning Behavior of Rainbow Trout (Salmo gairdneri) Populations of the Great Lakes

Abstract

Rainbow trout (Salmo gairdneri) populations of the Great Lakes showed a great variability in timing of spawning migrations and life histories. This variability was examined to determine if rainbow trout populations of the Great Lakes are comprised of discrete stocks. Differences in timing of migration and spawning indicated that at least one spawning population may be distinctive and that others may be in progressive stages towards emergence of discrete stocks. The innate ability of this species to adapt to different environmental conditions, together with its ability to 'home,' provide rainbow trout in the Great Lakes with the potential to develop discrete stocks. The management of this species that allows for the development of this potential is emphasized.Key words: rainbow trout. Great Lakes, stocks, migrations, spawning, life histories, homing