Habitat use and prey selection by mountain lions in an altered sagebrush steppe environment

Throughout the American West there is an increasing trend of encroachment of woody vegetation on previously open sagebrush steppe habitat. The Modoc Plateau in northeastern California has not been excluded from this encroachment trend and has seen an increase in western juniper (Juniperus occidentalis) densities, likely as a result of long-term fire suppression. Mountain lions (Puma concolor) have not previously been studied on the Modoc Plateau, and there is potential for an increase in cover due to juniper encroachment to benefit the hunting behavior of lions. To better understand if the presence of cover is being selected by mountain lions, 17 mountain lions were captured and fitted with GPS collars and their movements and diet were monitored. Using remotely obtained location data, I investigated spatially aggregated clusters of GPS points in search of mountain lion feeding sites and their associated kill sites. I created resource selection functions at both the study area and home range levels to test if lions were killing their prey in areas with higher ambush cover, or rather in areas with higher prey densities. Lions spent more time within parts of their home ranges that had larger western juniper basal area. For killing prey, lions selected areas with increased ambush cover and increased prey densities, compared to what was available within the study area. At the home range level, there was model uncertainty and no selection was observed. At a fine scale, lions selected for areas with more obstructed horizontal visibility, but showed no preference for areas closer to western junipers when killing prey. In areas with declining ungulate populations, there is potential for habitat to be managed by reducing the areas where ungulates are at risk to predation by lions. Through timber cuts and controlled burns, managers have the ability to restore the sage-steppe habitat and reduce areas where ungulates are at greater risk to mountain lion predation