Genetic diversity, gene flow, and source-sink dynamics of cougars in the Pacific Northwest

• Published in: Conservation genetics 2023-12, Vol.24 (6), p.793-806
• Main Authors: Wultsch, Claudia, Zeller, Katherine A., Welfelt, Lindsay S., Beausoleil, Richard A.
• Format: Article
• Language: English
• Subjects: Animal Genetics and Genomics; Anthropogenic factors; Biodiversity; Biomedical and Life Sciences; Carnivores; Conservation; Conservation Biology/Ecology; Decision support systems; Dynamics; Ecology; Evolutionary Biology; Gene flow; Genetic diversity; Genotypes; Habitat fragmentation; Human influences; Inbreeding; Life Sciences; Mountains; Movements; Plant Genetics and Genomics; Research Article; Source-sink relationships; Urbanization
• ISSN: 1566-0621; 1572-9737
• DOI: 10.1007/s10592-023-01532-3

Conservation and management of wide-ranging carnivores like cougars ( Puma concolor ), which occur across human-altered landscapes can benefit from an in-depth understanding of their genetic status. Here, we apply the largest collection of multi-locus genotypes currently available for cougars ( n  = 1,903) to provide a comprehensive assessment of genetic diversity, gene flow, and source-sink dynamics for cougars occurring across Washington, United States and south-central British Columbia, Canada. We found that cougars in the Olympic, Cascade, Kettle, Selkirk, and Blue Mountains ecosystems are genetically differentiated into two clusters with varying degrees of admixture, indicating moderate levels of gene flow across the area with the exception of the Olympic Peninsula and the Blue Mountains which form more distinct genetic groups. We detected several first-generation migrants confirming long-distance movements within our study system, but also observed that migration rates between areas were asymmetrical, which is an indication of genetic source-sink dynamics. Genetic diversity and inbreeding followed a clinal east-to-west pattern with Olympic Peninsula cougars having the lowest genetic diversity and highest inbreeding coefficients among all sites. Spatial autocorrelation results for cougars did not follow sex-specific patterns suggesting that anthropogenic pressures such as habitat fragmentation and/or mortality sources may have an impact on their spatial dynamics. As cougar habitat in the northwestern United States continues to be affected by rising levels of urbanization and anthropogenic activities, long-term regional genetic monitoring represents a critical decision-support tool for formulating effective cougar conservation and management actions to prevent further genetic decline and promote long-term persistence of cougar populations.