Using Cost Surface Analysis and Least Cost Paths to Analyze Dispersal of Gray Wolves in the Northern Rockies, U.S.A.
The recent delisting of gray wolves (Canis lupus) in the Northern Rockies region marks a change in the management scheme employed by state wildlife agencies. The wolf population in this region has expanded rapidly since its reintroduction in 1994 and has reached sufficient size to merit removal from the federal list of threatened and endangered species. The following study employs cost surface analysis to model wolf movements across the Northern Rockies region. An examination of wolf habitat selection in the region allows for the development of a friction surface by assigning different friction values to several landscape variables (land cover class, slope, and proximity to roads). This friction surface serves as the basis for the creation of least cost paths between known wolf territories. Buffers around these paths highlight areas of especial importance for wolf movements through the region. This model is corroborated by comparing the landscape variables in the paths and the buffered areas with known wolf habitat selection. The study found that the least cost paths closely mirrored wolf habitat selection. From the least cost paths, the study concludes that a regional perspective on wolf management will benefit the species as dispersal routes often cross political boundaries.
Cost surface snalysis, Least cost path, Gray wolf, Canis lupus, Dispersal, Wildlife management
Crossley, P. (2012). <i>Using cost surface analysis and least cost paths to analyze dispersal of gray wolves in the Northern Rockies, U.S.A.</i> (Unpublished thesis). Texas State University-San Marcos, San Marcos, Texas.