A Test of a Habitat Evaluation Procedure for Rocky Mountain Bighorn Sheep

Abstract

AbstractHabitat analysis is an important component of animal population restoration. We tested a habitat evaluation procedure for Rocky Mountain bighorn sheep (Ovis canadensis canadensis) using a geographic information system (GIS). We applied the model to eight bighorn sheep translocation sites in Colorado and compared the model's habitat suitability assessments with translocation results. The model considered the habitat unsuitable for four failed translocations, and did not recognize suitable habitat for four successful translocations. We performed a sensitivity analysis to determine how individual parameters affected model suitability assessments. To improve the model's ability to distinguish between suitable and unsuitable habitat, we relaxed the suitability criteria for four parameters: barriers created by dense vegetation, barriers created by fences, buffer zones on human use areas, and horizontal visibility. The refined model can be useful to bighorn sheep restoration efforts by facilitating evaluation of large areas of potential habitat, but numerical thresholds for required amounts of suitable habitat must consider the scale of data used for analysis.