Reproductive Behavior of Wild and Hatchery Lake Trout in the Drummond Island Refuge, Lake Huron

Lake trout served as the keystone predator and supported a valuable commercial fishery in the Laurentian Great Lakes until the 1940s, when overfishing and sea lamprey predation caused the extirpation of most populations. Despite annual stocking since the 1970s, rehabilitation of these populations, outside Lake Superior, has been slow. The potential reasons for lack of population re-establishment are numerous, but may be related to differences in spawning behavior, site selection, and reproductive success between hatchery and wild trout. Comparative studies of spawning behavior and habitat use between hatchery and wild lake trout do not exist for the Great Lakes due to the difficulties of studying these behaviors in large water bodies. However, recent advances in acoustic telemetry have made such studies possible. In this 3-year study, acoustic telemetry is being used to describe and compare the behavior of wild and hatchery lake trout in a ~16 km² region of the Drummond Island Refuge, Lake Huron. To date, we have identified 3 distinct spawning sites in the study area, and the movement data suggest that differences in behavior and habitat use exist among hatchery and wild and male and female lake trout.