An Assessment of Caribou (Rangifer tarandus) Genomic Diversity and Structure in Western Canada to Guide Species Conservation and Management

• Main Author: Michalak, Anita
• Other Authors: Poissant, Jocelyn, Musiani, Marco, Polfus, Jean, Rogers, Sean
• Format: Master Thesis
• Language: English
• Published: Veterinary Medicine 2023
• Subjects: conservation genomics; population structure; genetic differentiation; clustering; evolutionarily significant units; ecotypes; endangered wildlife; Forestry and Wildlife; Ecology; Genetics; Zoology; British Columbia; Canada; Rangifer; Rangifer tarandus
• Online Access: http://hdl.handle.net/1880/115800; https://doi.org/10.11575/PRISM/40705

Human-induced environmental change is one of the biggest threats to global biological diversity, and the resulting environmental conditions have made it increasingly difficult for species to adapt and survive. The use of genomic technologies, such as the inference of genetic structure, can aid species conservation and prevent population declines. Particularly for caribou (Rangifer tarandus), which are considered an at-risk species across Canada, determining population genetic structure can help delineate units for conservation while detecting potentially cryptic population structure and diversity as well as undetected and/or mislabeled populations. For my M.Sc. thesis, I studied genomic diversity in caribou sampled throughout western Canada to better characterize population structure and supplement previous genetic studies conducted in this region. I accomplished this using several population structure inference methods and by combining individual-based genomic and spatial data for 658 individuals derived from 41 herds across British Columbia (BC) and Alberta (AB). Results indicate that population structure inferred from genomic data reflects neither past nor present caribou classification schemes. Instead, caribou genetic differentiation in BC and AB is best reflected at K=4 clusters, which primarily: (1) identifies a potential new conservation unit composed of individuals belonging to Itcha-Ilgachuz and neighboring subpopulations, and (2) redefines the boundaries of existing populations. Despite the need for multiple lines of evidence to provide complementary criteria for designating distinct units for conservation or populations, my work illustrates how genomics can help inform and improve the delineation of such conservation and management units for caribou.