Landscape-level analysis of mountain goat population connectivity in Washington and southern British Columbia
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Habitat fragmentation and habitat loss diminish population connectivity, reducing genetic diversity and increasing extinction risk over time. Improving connectivity is widely recommended to preserve the long-term viability of populations, but this requires accurate knowledge of how landscapes influence connectivity. Detectability of landscape effects on gene flow is highly dependent on landscape context, and drawing conclusions from single landscape studies may lead to ineffective management strategies. We present a novel approach to elucidate regional variation in the relative importance of landscape variable effects on gene flow. We demonstrate this approach by evaluating gene flow between isolated, genetically impoverished mountain goat (Oreamnos americanus) populations in Washington and much larger, genetically robust populations in southern British Columbia. We used geneland to identify steep genetic gradients and then employed individual-based landscape genetics in a causal modeling framework to independently evaluate landscape variables that may be generating each of these genetic gradients. Our results support previous findings that freeways, highways, water, agriculture and urban landcover limit gene flow in this species. Additionally, we found that a previously unsupported landscape variable, distance to escape terrain, also limits gene flow in some contexts. By integrating geneland and individual-based methods we effectively identified regional limiting factors that have landscape-level implications for population viability.
KeywordsPopulation connectivity geneland Circuit theory Causal modeling Oreamnos americanus
We thank Andrew Shirk (University of Washington), Cliff Rice (WDFW), Brian Harris, Darryl Reynolds and Christ Proctor (BC Ministry of Forests, Lands and Natural Resource Operations), Cliff Nietvelt (BC Ministry of the Environment), Katy Chambers (BC Parks and Protected Areas), Aaron Shafer (Uppsala University), Kim Poole (Aurora Wildlife Research) and David Paetkau (Wildlife Genetics International) for their collaboration. We thank Samuel Wasser and Rebecca Nelson Booth (University of Washington) for assistance developing sample collection protocol and Ken Warheit, Scott Blankenship and Cheryl Dean (WDFW) for genotyping. Funding was provided by the WDFW Aquatic Lands Enhancement Account, Seattle City Light, the Mountaineers Foundation, the Mazamas, the Safari Club International Foundation, the Washington Chapter of the Wildlife Society, Western Washington University Office of Research and Sponsored Programs and Huxley College of the Environment.
Conflict of interest
The authors declare that they have no conflict of interest.
- Amos J, Bennet AF, Mac Nally R, Newell G, Radford JQ, Pavlova A, Thompson J, White M, Sunnucks P (2012) Predicting landscape genetic consequences of habitat loss, fragmentation and mobility for species of woodland birds. PLoS One 7:1–12Google Scholar
- Butchart SHM, Walpole M, Collen B, van Strien A, Scharlemann JPW, Almond REA, Baillie JEM, Bomhard B, Brown C, Bruno J, Carpenter KE, Carr GM, Chanson J, Chenery AM, Csirke J, Davidson NC, Dentener F, Foster M, Galli A, Galloway JN, Genovesi P, Gregory RD, Hockings M, Kapos V, Lamarque JF, Leverington F, Loh J, McGeoch MA, McRae L, Minasyan A, Morcillo MH, Oldfield TEE, Pauly D, Quader S, Revenga C, Sauer JR, Skolnik B, Spear D, Stanwell-Smith D, Stuart SN, Symes A, Tierney M, Tyrrell TD, Vie JC, Watson R (2010) Global biodiversity: indicators of recent declines. Science 328:1164–1168CrossRefPubMedGoogle Scholar
- Festa-Bianchet M, Côté S (2008) Mountain goats: ecology, behavior, and conservation of an alpine ungulate. Island Press, Washington DCGoogle Scholar
- Goslee SC, Urban DL (2007) The ecodist package for dissimilarity-based analysis of ecological data. J Stat Softw 22:1–19Google Scholar
- Houston DB, Schreiner EG, Moorhead BB (1994) Mountain goats in Olympic National Park: biology and management of an introduced species. USDI National Park Service Scientific Monograph, DenverGoogle Scholar
- Legendre P, Legendre L (1998) Numerical ecology, 2nd edn. Elsevier, AmsterdamGoogle Scholar
- McRae BH, Shah VB (2009) Circuitscape user guide. The University of California, Santa Barbara. http://www.circuitscape.org. Accessed 12 Sep 2011
- Parks LC (2013) Mountain goat genetic diversity and population connectivity in Washington and southern British Columbia. Thesis, Western Washington UniversityGoogle Scholar
- Poole KG, Reynolds DM (2010) Mt. Meager mountain goat aerial survey and DNA census, 2009. British Columbia Conservation Foundation. http://www.env.gov.bc.ca/wildlife/wsi/reports/4668_WSI_4668_RPT_2009.PDF. Accessed 14 Apr 2012
- Raymond M, Rousset F (1995) GENEPOP (Version 1.2): population genetics software for exact tests and ecumenicism. J Hered 86:248–249Google Scholar
- Shirk AJ (2009) Mountain goat genetic structure, molecular diversity, and gene flow in the Cascade Range, Washington. Thesis, Western Washington UniversityGoogle Scholar
- Smith CA (1994) Bi-level analysis of habitat selection by mountain goats in coastal Alaska. Proceedings of the biennial symposium of the northern wild sheep and goat council, vol, pp 5366–379Google Scholar
- Thomas CD, Cameron A, Green RE, Bakkenes M, Beaumont LJ, Collingham YC, Erasmus BFN, de Siqueira MF, Grainger A, Hannah L, Hughes L, Huntley B, van Jaarsveld AS, Midgley GF, Miles L, Ortega-Huerta MA, Peterson AT, Phillips OL, Williams SE (2004) Extinction risk from climate change. Nature 427:145–148CrossRefPubMedGoogle Scholar
- US Geological Survey, GAP Analysis Program (GAP) (2012) Protected Areas Database of the United States (PADUS), version 1.3Google Scholar
- Warren MJ, Wallin DO, Beausoleil RA, Warheit KI (2015) Genetic structure and landscape resistance to gene flow in cougars in Washington and southern British Columbia. Manuscript submitted for publicationGoogle Scholar
- Washington Wildlife Habitat Connectivity Working Group (WHCWG) (2010) Washington connected landscapes project: statewide analysis. Washington Departments of Fish and Wildlife, and Transportation, Olympia. http://waconnected.org/statewide-analysis/. Accessed 15 Oct 2011
- Wells A, Wallin DO, Rice CG, Wan-Ying C (2011) GPS bias correction and habitat selection by mountain goats. Remote Sens 3:435–459Google Scholar