MOUNTAIN LION RESEARCH
Mountain Lion Habitat Use
We used GPS collar data to examine habitat use by mountain lions in the Davis Mountains. We looked at 4 criteria of resource selection: elevation, ecological site, fine scale terrain ruggedness, and broad scale terrain ruggedness.
A preliminary habitat model for mountain lion in the Trans-Pecos. High habitat quality is noted in red with low habitat quality noted in blue. The model illustrates the vast amount of high quality habitat in west Texas.
Measures of terrain ruggedness are calculated in a Geographic Information System (GIS) by looking at the changes in elevation and slope within a given area, to determine how rugged or smooth the landscape is. The fine scale terrain ruggedness criteria calculated ruggedness over a small area (around 5 acres), while broad scale terrain ruggedness was calculated over a larger area (around 272 acres).
Ecological sites are classifications determined by the Natural Resources Conservation Service (NRCS) that take into account various conditions including the soil type, topography, region, and moisture conditions in an area. This information is used to classify the type of vegetation that is likely to be found in that area.
For each of the 4 resource selection criteria, we determined which habitats mountain lions selected and which they avoided. We looked at habitat use for the population as a whole, as well as for individual mountain lions within their home range.
Individual mountain lions and the overall population selected for the highest elevations (≥6,234 feet). Mountain lions also selected for the most rugged habitat on both a fine and broad scale.
Mountain lions preferred the mountain loam and canyon ecological sites. The mountain loam ecological site is found on silty soils on igneous hills and mountains and common plants include ponderosa pine, gray and silverleaf oak, and alligator juniper. Typical plants found in the canyon ecological site include oaks, ponderosa and pinyon pines, alligator juniper, and Texas madrone. In contrast, the ecological sites avoided by mountain lions tend to be dominated by grass species. This is likely indicative of mountain lions selecting for habitat that provides cover, which is important for safety and stalking prey.
GPS collars allow us to monitor habitat use with precise detail. This data will help us refine our knowledge of where suitable mountain lion habitat is located within the Trans-Pecos.