The purpose of this project is to work collaboratively to produce a population viability analysis (PVA) for mountain lions in the region of Santa Monica Mountains National Recreation Area. Mountain lions are the last remaining large carnivore in the park and a high profile species that is especially vulnerable to the effects of urbanization. Because of their very large home ranges and dispersal distances, mountain lions require large, intact natural areas and functional connections between them. A PVA will provide concrete information about the prospects for this species in the park over the long-term. The La Kretz Center for California Conservation Science at UCLA will hire a post-doctoral researcher, Dr. John Benson, to work with National Park Service wildlife staff on the PVA. Dr. Benson will be a jointly funded by the LKC and the National Park Service (NPS). Specifically, during this two-year project, Dr. Benson will work with NPS staff to compile all the available information relevant to the model, construct the model for mountain lions in the Santa Monica Mountains, and apply various scenarios relevant to conservation in the region, including increased and decreased connectivity between remaining natural areas and increased urban development. John will also work with faculty at UCLA to explore how genetic data can be brought to bear on this population model and how similar modeling exercises may work to benefit endangered species in California. Dr. Benson will also participate in LKC and NPS outreach activities, including giving presentations to NPS staff and the public, and will participate in decision-making meetings and other conservation activities for which his research expertise is appropriate. Recipient will produce a report on the results of the PVA, as well as articles for publication.