Cooperative Fish and Wildlife Research Units Program: Pennsylvania
Education, Research and Technical Assistance for Managing Our Natural Resources

Topography influences movement trajectories, quality of forages used, and behavioral response of large herbivores to anthropogenic disturbances, but research is lacking on the influence of terrain complexity on size of home range. Size of home range usually is based on planimetric area and therefore rarely accounts for the true surface area traversed by an animal. We conducted radiotelemetry on bighorn sheep (Ovis canadensis), Rocky Mountain elk (Cervus elaphus), mule deer (Odocoileus hemionus), and white-tailed deer (O. virginianus) equipped with VHF collars at 3 sites from 2002 to 2006 to document size of home range in areas that ranged from 400 m to 1,500 m in elevation with varying degrees of topographic ruggedness in the Great Plains. We used the fixed-kernel method to compare size of 95% home range between 2-dimensional (planimetric) and 3-dimensional (topographic) estimates. Mean (± SD) percent increase in size of home range from planimetric to topographic was 2.8% (± 0.19), 1.2 % (± 0.52), 1.0% (± 0.43), and 0.1% (± 0.40) for bighorn sheep, elk, mule deer, and white-tailed deer, respectively. We found little difference in size between planimetric and topographic home range for our species suggesting that planimetric home range techniques are likely valid in the Great Plains and similar regions but both home range methods should be compared in other regions with high topographic relief (e.g., Rocky Mountain region).