POPULATION GENOMICS OF BLANDING’S TURTLE ON A REGIONAL SCALE IN THE MIDWEST

Maintaining high genetic diversity within and among wildlife populations is an important component to the management of threatened species. Population genomics utilizes recent advancements in high-throughput next-generation sequencing to obtain genome-wide data that can yield deeper perspectives on intraspecific genetic variation and elucidate evolutionary significant units that may require conservation management or augmentation. The semi-aquatic Blanding’s Turtle (Emydoidea blandingii) has experienced drastic population declines in North America due in large part to anthropogenic activities. This species is listed as threatened or endangered across most of its range. A population genomic study can help to understand the status of this species and guide future management practices. Hence, a population genomic analysis was conducted using 3RAD to discover and analyze SNPs across the range using samples from Nebraska, Indiana, Michigan, Ohio, and Nova Scotia,. Range-wide analysis used 8,602 SNPs while analysis within the Great Lakes region used 7,893 SNPs. High amounts of missing data were found across all individuals and loci. Low levels of genetic variation relative to other turtle species were detected both across the range and within the Great Lakes region. Minimal population structure was detected range-wide via clustering and admixture analyses; however, a signal of population differentiation was detected among Nebraska, Nova Scotia, and the Great Lakes. Clustering and differentiation analyses focused on the Great Lakes region found a signal of population structure and differences between the Lake Michigan and Lake Erie watershed. These results may prove useful for conservation management of Blanding’s Turtle populations, particularly related to efforts using translocation or head-starting practices.