Genetic Structure of Yellow Perch Populations in Coastal Areas of Eastern Lake Michigan

Genetic population substructure is often overlooked because of discontinuities between management and actual population structure as in the case of yellow perch, an ecologically and economically important indigenous fish species in the Laurentian Great Lakes. A knowledge gaps pertaining to the natural history of yellow perch relates to the biological connectivity between nearshore Lake Michigan and drowned river mouth (DRM) lakes, where it remains unclear whether resident yellow perch from Lake Michigan use DRM lakes for spawning or whether DRM lakes contribute to nearshore yellow perch populations in Lake Michigan. I used DNA fingerprinting (genotyping) to explore biological connectivity between DRM lakes and nearshore Lake Michigan during autumn by: (1) comparing the genetic structure of yellow perch collected from littoral habitats among DRM lakes, and (2) comparing genetic structure of yellow perch from DRM lakes with nearshore Lake Michigan. I hypothesized that (a) yellow perch from Lake Michigan move into DRM lakes during autumn but do not spawn, (b) yellow perch from DRM lakes differ genetically from nearshore Lake Michigan and do not form a panmictic population, and (c) DRM lakes will exhibit genetic isolation by distance. Overall, yellow perch exhibited low genetic diversity. The southern DRM lakes (i.e., Muskegon, White, and Pentwater lakes) were genetically similar to each other. Lake Charlevoix was genetically different from all other sites, but most similar to nearshore northern Lake Michigan. Nearshore northern Lake Michigan was intermediate to Lake Charlevoix and southern Lake Michigan. Analysis of a subset of yellow perch from Muskegon Lake revealed that fish captured in deep-water habitat differed genetically from individuals from littoral habitat and were most genetically similar to nearshore southern Lake Michigan. Understanding yellow perch spawning stocks is important for managing and maintaining a yellow perch fishery in eastern Lake Michigan