genetic legacy of extirpation and re-colonization in Vancouver Island wolves

• Published in: Conservation genetics Vol. 11; no. 2; pp. 547 - 556
• Main Authors: Muñoz-Fuentes, Violeta, Darimont, Chris T, Paquet, Paul C, Leonard, Jennifer A
• Format: Journal Article
• Language: English
• Published: Dordrecht Dordrecht : Springer Netherlands 01.04.2010; Springer Netherlands; Springer Nature B.V
• Subjects: Animal Genetics and Genomics; at-risk population; Biodiversity; Biologi; Biology; Biomedical and Life Sciences; British Columbia; Colonization; Conservation biology; Conservation Biology/Ecology; Conservation genetics; Dogs; Domestic animals; Ecology; Evolutionary Biology; extinction; Genetics; Haplotypes; Hybridization; introgression; Life Sciences; microsatellite repeats; Mitochondrial DNA; NATURAL SCIENCES; NATURVETENSKAP; Offspring; pets; Plant Genetics and Genomics; Population genetics; Population number; population size; progeny; Research Article; Species extinction; Wildlife management; Wolves; British Columbia; Canada; Domestic dog; Microsatellites; mtDNA; Allee effect; Museum specimens; Historical DNA; Hybridization; Wolf; Introgression
• ISSN: 1566-0621; 1572-9737; 1572-9737
• DOI: 10.1007/s10592-009-9974-1

Hybridization between wild and domestic species is of conservation concern because it can result in the loss of adaptations and/or disappearance of a distinct taxon. Wolves from Vancouver Island, British Columbia (Canada), have been subject to several eradication campaigns during the twentieth century and were considered virtually extirpated between 1950 and 1970. In this study, we use control region mitochondrial DNA sequences and 13 autosomal microsatellite loci to characterize Vancouver Island wolves as well as dogs from British Columbia. We observe a turnover in the haplotypes of wolves sampled before and after the 1950-1970 period, when there was no permanent wolf population on the island, supporting the probable local extinction of wolves on Vancouver Island during this time, followed by re-colonization of the island by wolves from mainland British Columbia. In addition, we report the presence of a domestic dog mtDNA haplotype in three individuals eliminated in 1986 that were morphologically identified as wolves. Here we show that Vancouver Island wolves were also identified as wolves based on autosomal microsatellite data. We attribute the hybridization event to the episodically small size of this population during the re-colonization event. Our results demonstrate that at least one female hybrid offspring, resulting from a cross of a male wolf and a female dog or a female hybrid pet with dog mtDNA, successfully introgressed into the wolf population. No dog mtDNA has been previously reported in a population of wild wolves. Genetic data show that Vancouver Island wolves are distinct from dogs and thus should be recognized as a population of wild wolves. We suggest that the introgression took place due to the Allee effect, specifically a lack of mates when population size was low. Our findings exemplify how small populations are at risk of hybridization.