Integrating archaeology and ancient DNA analysis to address invasive species colonization in the Gulf of Alaska

• Published in: Conservation Biology
• Main Authors: West, Catherine, Hofman, Courtney A., Ebbert, Steve, Martin, John, Shirazi, Sabrina, Dunning, Samantha, Maldonado, Jesus E.
• Format: Article in Journal/Newspaper
• Language: English
• Published: WILEY 2017
• Subjects: Science & technology; Life sciences & biomedicine; Biodiversity conservation; Ecology; Environmental sciences; Biodiversity & conservation; Environmental sciences & ecology; Ancient translocation; Ground squirrel; Invasive species management; Urocitellus parryii; Zooarchaeology; Squirrels spermophilus-parryii; Chirikof island; Bone; History; Conservation; Management; Northwest; Collagen; Mammals; Ardilla terrestre; Manejo de especies invasoras; Translocación antigua; zooarqueología; Alaska; Animals; Archaeology; Conservation of natural resources; DNA; ancient; Humans; Introduced species; Sciuridae; Biological sciences; Agricultural and veterinary sciences; Arctic; Gulf of Alaska; Arctic ground squirrel
• Online Access: https://hdl.handle.net/2144/33692; http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000409319400019&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=6e74115fe3da270499c3d65c9b17d654; https://doi.org/10.1111/cobi.12865

The intentional and unintentional movement of plants and animals by humans has transformed ecosystems and landscapes globally. Assessing when and how a species was introduced are central to managing these transformed landscapes, particularly in island environments. In the Gulf of Alaska, there is considerable interest in the history of mammal introductions and rehabilitating Gulf of Alaska island environments by eradicating mammals classified as invasive species. The Arctic ground squirrel (Urocitellus parryii) is of concern because it affects vegetation and seabirds on Gulf of Alaska islands. This animal is assumed to have been introduced by historic settlers; however, ground squirrel remains in the prehistoric archaeological record of Chirikof Island, Alaska, challenge this timeline and suggest they colonized the islands long ago. We used 3 lines of evidence to address this problem: direct radiocarbon dating of archaeological squirrel remains; evidence of prehistoric human use of squirrels; and ancient DNA analysis of dated squirrel remains. Chirikof squirrels dated to at least 2000 years ago, and cut marks on squirrel bones suggested prehistoric use by people. Ancient squirrels also shared a mitochondrial haplotype with modern Chirikof squirrels. These results suggest that squirrels have been on Chirikof longer than previously assumed and that the current population of squirrels is closely related to the ancient population. Thus, it appears ground squirrels are not a recent, human‐mediated introduction and may have colonized the island via a natural dispersal event or an ancient human translocation. We thank T. Rick, D. Grayson, R. Fleischer, M. Hawkins, A. West, and C. Mikeska for their contributions to this research. We also thank 3 reviewers and the editors of Conservation Biology who greatly improved this paper. This work was funded by the National Geographic Society, the University of Maine, the Smithsonian Institution, and Boston University. The findings and conclusions in this article are those of ...