In collaboration with the UC Davis Wildlife Health Center Mountain Lion and Bobcat Project, I have been working with mountain lions in southern California. The study site, between L.A. and San Diego, is one of the most heavily settled areas in the U.S. with a projected population of 40 million people by 2050. Mountain lions are becoming increasingly cut off from one another by multi-lane highways and expanding human development. The Santa Ana mountain lion population has been shown to have one of the lowest levels of genetic diversity in the country, raising concerns that inbreeding will eventually lead to the extinction of this population. I have been using data from mountain lions outfitted with GPS telemetry collars to examine how mountain lions are moving through this landscape — both natural and human dominated — so that we can better understand their behaviors and better model corridors for conservation. I am currently using Resource Selection Functions and Corridor Models to identify important resource use areas and connections between them. This information will be incorporated into the Northern San Diego County Multi-Species Conservation Plan to promote mountain lion conservation in this region.