Fine-scale population genetic structure of Lake Erie yellow perch Perca flavescens (Teleostei: Percidae): Any relation to management units?

Discerning the genetic basis underlying fine-scale population genetic structure of exploited native species, and its relationship to effective management units is a critical goal for effective conservation. The present study provides the first fine-scale high-resolution test of Lake Erie yellow perch Perca flavescens populations, which have fluctuated due to unstable recruitment patterns and exploitation.  Fifteen nuclear DNA microsatellite loci are analyzed for 569 spawning individuals from 13 Lake Erie spawning sites, in comparison to outlying reference populations spawning in Lake St. Clair and Lake Ontario. Additional comparisons are made to test for possible variation between the sexes and among size/ age cohorts at selected sites.  Analyses include pairwise divergence comparisons, hierarchical AMOVA partitioning, Mantel regression, genetic distance trees, Bayesian assignment tests, 3-dimensional factorial correspondence, and Monmonier geographic networks.  Results demonstrate that yellow perch spawning groups in Lake Erie are each genetically distinguishable and there are no significant differences between the sexes at given sites. Some spawning groups show high genetic divergence and greater contribution to genetic diversity to lake-wide distributions.  The relationships among spawning groups show little congruence to current management units. The present results underlie the necessity to conserve and improve spawning habitat in order to maintain genetic stocks.