Preliminary Investigation Of Spawning Habitat Conditions And Reproduction Of Lake Trout In Eastern Lake Michigan Near Port Sheldon, Michigan

Researchers have implicated a variety of factors in lake trout reproductive failure (Table 1). Our recent studies (Dorr et al. 1981; Jude et al. 1981) in Lake Michigan suggest that eutrophication, numerical insufficiency or inappropriate behavior of spawners, maladaptation of eggs to site-specific incubation conditions, and predation (by fish and crayfish) remain plausible causes of reproductive failure. Conflicting laboratory evidence has been presented regarding effects of toxic substances (PCBs, DDT) on trout reproduction and progeny survival (Stauffer 1979; Willford 1981). Quite likely, several of the above processes may act synergistically to reduce reproductive success. Grant no. NA-80-AA-D-00072