Title: Assessing spatio-temporal patterns of genetic diversity and translocation outcomes in the Bi-State Distinct Population Segment greater sage-grouse (Centrocercus urophasianus)

Program: Biology MS

Committee Chair: Stephanie Galla

Committee: Stephanie Galla, Peter Coates, Julie Heath

Abstract: Greater sage-grouse along the California-Nevada border, known as Bi-State sage-grouse (BSSG), are geographically isolated, genetically distinct, and currently listed with a proposed threatened status under the Endangered Species Act. Conservation of a population like the BSSG requires a greater understanding of both the contemporary patterns of genetic diversity and the effectiveness of management actions intended to mitigate genetic and demographic risk. This thesis aims to characterize genetic diversity across space, time, and management actions in BSSG in response to conservation practitioner needs in the Bi-State. To meet this aim, this thesis had two primary objectives: 1) to characterize genetic diversity, population structure, and connectivity patterns through a spatio-temporal analysis of genotypic data in BSSG, and 2) to evaluate the genetic outcomes of conservation translocations implemented to bolster a small, declining Bi-State population, Parker Meadows. Using 15 microsatellite loci, we found that genetic diversity metrics—including allelic richness, heterozygosity (HO and HE), and inbreeding coefficients—were moderate across most populations. Spatial genetic structure was detected throughout the Bi-State, with significant differentiation among most populations, corresponding with limited dispersal, rugged topography, and small effective population sizes. Temporal analyses across a decade revealed overall genetic diversity and structure have remained stable; however, non-significant increases of genetic differentiation in the peripheral populations suggest the potential for continued genetic drift and the effects of genetic erosion. Although non-significant, the Parker Meadows population experienced increased heterozygosity, reduced inbreeding, decreased genetic differentiation, and increased admixture after translocation efforts; however, allelic richness did significantly increase post-translocations in Parker Meadows. The findings of this thesis provide an updated genetic baseline for the BSSG and demonstrate the benefit of combining genetic assessments with evaluations of applied management actions.