Genetic Status of the Northernmost Population of the Endangered and Elusive Huemul Deer, Hippocamelus bisulcus

Small, isolated, and fragmented populations often exhibit low levels of genetic diversity as a result of genetic drift, limited gene flow, and inbreeding. Huemul (Hippocamelus bisulcus) is a medium-sized South American deer categorized as endangered by the International Union for Conservation of Nature (IUCN). Huemul in its northernmost range was previously distributed in Central Chile between 36° S and 37° S, but its current distribution and conservation status in the region are poorly documented. We used non-invasive genetic approaches to assess the genetic diversity, population connectivity, and demographic history of the huemul’s northernmost population using nuclear microsatellite markers from fecal samples of wild individuals. Observed nuclear DNA genetic variation (Ho = 0.2958 ± 0.0318) was moderate, and allelic richness was low (Ar = 3.43–4.01), consistent with the theoretical expectation that isolated populations may retain heterozygosity while losing allelic richness more rapidly. However, the estimated nuclear DNA effective population size was low (Ne = 47; 95% CI: 19.2–∞). Demographic simulations project continued loss of genetic diversity under all scenarios modeled. Our results provide a foundation for further study of this population and provide the genetic data necessary to design detailed management plans to ensure the persistence of healthy populations of this rare and elusive deer.