Habitat use by female desert bighorn sheep in the Fra Cristobal Mountains, New Mexico, USA

Abstract

Mexican desert bighorn sheep (Ovis canadensis mexicana) populations have declined since the 1980s, and restoration efforts are necessary to establish viable populations. Mexican desert bighorn sheep were translocated to the Fra Cristobal Mountains of south-central New Mexico in 1995. We described seasonal habitats used by female desert bighorn sheep by comparing characteristics of radiolocations with random locations within their home range. We developed a geographic information system to derive aspect, distance to steep slopes, elevation, slope, substrate associations, terrain ruggedness, and visibility. We developed seasonal logistic regression models that incorporated distance to 60% slope patches, ruggedness, slope, substrate, and visibility. Habitat characteristics at bighorn sheep locations were similar among seasons. Bighorn sheep locations were on steeper and more rugged terrain, closer to topography with a 60% slope, and had lower visibility than random locations. Based on our description of habitat selection by sheep, managers in New Mexico may need to reassess the amount of escape habitat in restoration areas to prioritize translocations and plan to manage predators.