Mitochondrial DNA Sequence Variation in Saugers

Abstract

Despite extensive work documenting genetic variation in walleyes Sander vitreus, relatively little is known about the distribution of variation in saugers S. canadensis. Mitochondrial DNA sequence variation was surveyed among samples of saugers to assess the magnitude and distribution of variation among sauger populations. Sequencing of 847 bases of the mitochondrial DNA control region in 60 individuals yielded 19 haplotypes that differed by 0.1–0.8%. Several haplotypes were broadly distributed across the range sampled. The data support the hypothesis of a single glacial refugium. There was no evidence of multiple refugia within which sauger populations could have differentiated. A single Mississippian refuge is consistent with the data and with likely routes of colonization of the Great Lakes–St. Lawrence River and the Hudson Bay drainage. A mismatch distribution analysis among haplotypes suggested a recent population expansion; the presence of haplotypes with broad distributions is also consistent with a recent range expansion. Little differentiation among sauger haplotypes suggests a recent divergence.

Received December 7, 2011; accepted December 20, 2011

ACKNOWLEDGMENTS

I thank the following individuals for their help in obtaining specimens; J. Negus, K. Tjemeland, C. Amadio, G. Sass, M. Docker, M. Porath, T. Larson, K. Zipfel, C. O’Bara, S. Schell, D. Nelson, K. Hartel, J. Epifanio, J. Hammonds, R. Dames, V. Travenichek, J. Quinn, P. Talmage, T. Heinrich, and R. Leary. Laboratory assistance was provided by D. Benders, K. Andino, A. Hoffman, and A. Marko. I thank S. Kuchta for help with the data analysis. I acknowledge the support of the West Virginia Department of Natural Resources; the Ohio Center for Ecology and Evolution Studies, Ohio University; and the Department of Biological Sciences, Ohio University.