Population genetic structure of American Black Bear (Ursus americanus) in Nova Scotia, Canada

Abstract

The population genetic structure of American Black Bears (Ursus americanus) in the Maritimes Provinces, Canada, with an emphasis on Nova Scotia, was examined. The study used hunter-sourced tooth samples from across Nova Scotia, as well as samples from New Brunswick. Allelic variation was examined for a suite of 15 microsatellite markers. Population structure was assessed using a Bayesian clustering method (STRUCTURE) and by conducting an isolation by distance (IBD) test. Three weakly differentiated genetic subpopulations were found with their general geographic locations being New Brunswick, Northeastern Nova Scotia, and Southwestern Nova Scotia. The New Brunswick subpopulation had higher measures of genetic diversity as well as effective population size relative to both subpopulations in Nova Scotia, but in particular compared to the Southwestern Nova Scotia subpopulation.
The Shubenacadie Canal system, primarily comprised of the Shubenacadie River and Shubenacadie Grand Lake, is the geological feature separating the two subpopulations of Black Bears found in Nova Scotia.

Keywords: Black Bears, gene flow, microsatellites, genetic diversity, inbreeding