title: Preferred habitat and effective population size drive landscape genetic patterns in an endangered species.
abstract: Landscape genetics provides a framework for pinpointing environmental features that determine the important exchange of migrants among populations. These studies usually test the significance of environmental variables on gene flow, yet ignore one fundamental driver of genetic variation in small populations, effective population size, N(e). W(e) combined both approaches in evaluating genetic connectivity of a threatened ungulate, woodland caribou. We used least-cost paths to calculate matrices of resistance distance for landscape variables (preferred habitat, anthropogenic features and predation risk) and population-pairwise harmonic means of N(e), and correlated them with genetic distances, FST and D(c). Results showed that spatial configuration of preferred habitat and Ne were the two best predictors of genetic relationships. Additionally, controlling for the effect of Ne increased the strength of correlations of environmental variables with genetic distance, highlighting the significant underlying effect of Ne in modulating genetic drift and perceived spatial connectivity. We therefore have provided empirical support to emphasize preventing increased habitat loss and promoting population growth to ensure metapopulation viability.
authors.affiliation: Faculties of Environmental Design and Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada T2N 1N4. byweck@gmail.com
authors.forename: Byron V
authors.initials: BV
authors.lastname: Weckworth
authors.forename: Marco
authors.initials: M
authors.lastname: Musiani
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Decesare
authors.forename: Allan D
authors.initials: AD
authors.lastname: McDevitt
authors.forename: Mark
authors.initials: M
authors.lastname: Hebblewhite
authors.forename: Stefano
authors.initials: S
authors.lastname: Mariani
mesh_terms: D000416:Alberta; D000818:Animals; D001955:British Columbia; D003247:Conservation of Natural Resources; D017753:Ecosystem; D056727:Endangered Species; D020387:Food Chain; D014644:Genetic Variation; D018895:Microsatellite Repeats; D008954:Models, Biological; D011156:Population Density; D012053:Reindeer / Q000235:genetics / Q000502:physiology*
keywords: Canadian Rockies; Rangifer tarandus caribou; genetic drift; habitat fragmentation; landscape genetics; least-cost paths