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Density-independent survival of wild lake trout in the Apostle Islands area of Lake Superior

Charles R. Bronte·Stephen T. Schram·James H. Selgeby·Bruce L. Swanson
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Abstract

The lake trout ( Salvelinus namaycush ) stock at Gull Island Shoal in western Lake Superior was one of only a few stocks of lean lake trout in the Great Lakes that survived overfishing and predation by the sea lamprey ( Petromyzon marinus ). Since the mid 1960s, the abundance of wild recruits measured at age 0 and the number of age-7 to -11 wild fish recruited to the fishable stock have increased. We used the Varley-Gradwell method to test for density-dependent survival between these life stages. Survival from age-0 to ages 7–11 was not affected by increasing density, which suggests that further increases in recruitment and stock size are still possible. We suggest that testing for the existence of density-dependent survival can be used to indicate when lake trout populations are rehabilitated.

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BibTeXRIS

Charles R. Bronte, Stephen T. Schram, James H. Selgeby, Bruce L. Swanson. 1995. Density-independent survival of wild lake trout in the Apostle Islands area of Lake Superior. https://doi.org/10.1016/s0380-1330(95)71097-8

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