Genetic Diversity Among Historical Collections of Two Sander Species from Lake Erie: Comparisons of Microsatellite DNA and SNP Data

Genomic tools such as Single Nucleotide Polymorphisms (SNPs) have the potential to improve our understanding of contemporary and historical population structure in the Great Lakes region.  Before their collapse between 1950 and 1970, members of the genus Sander (walleye, blue pike, and sauger) from Lake Erie supported a world-class fishery. Blue pike were considered extinct in America in 1983 and in Canada in 1985.  Although they are considered to be subspecies of walleye, questions remain about their taxonomic status that have been difficult to address with genetic techniques due to the scarcity of historical samples that yield DNA of sufficient quality.  In addition to their value for population discrimination, the characteristics of SNPs have potential to provide information using degraded DNA from sources such as museum specimens and scale archives.  We developed a candidate SNP library for walleye and tested inheritance of selected SNPs in walleye from the Lake Manitou hatchery strain, and compared diversity in contemporary and historical walleye and blue pike samples from Lake Erie.  Comparisons between analyses using microsatellite DNA loci and SNPs allowed examination of sensitivities of each marker type and  provide initial insights into population structure and changes in diversity that have occurred over time.