Inbreeding A Growing Problem With Mountain Lions At Santa Monica Mountains National Recreation Area

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The father of this mountain lion kitten, P-32, is also the father of its mother. NPS photo.

Inbreeding, long seen as a problem with the Florida panther population in Big Cypress National Preserve in Florida, is evolving into more of a problem with mountain lions in Santa Monica Mountains National Recreation Area in California.

Wildlife biologists at the NRA say preliminary DNA results from three mountain lion kittens born in the Santa Monica Mountains last month indicate they are the result of inbreeding. The results underscore the need for improvements to the wildlife corridor that is currently obstructed by the 101 Freeway in Agoura Hills, NRA officials say.

"Unfortunately, this litter of kittens is the latest example of first-order inbreeding in which a father mates with his offspring," said Dr. Seth Riley, an urban wildlife expert at Santa Monica Mountains National Recreation Area. "Allowing safe passage from the Simi Hills into the Santa Monica Mountains is our best shot at addressing the lack of genetic diversity in the local population."

The preliminary paternity results from UCLA's Robert Wayne Lab indicate that Puma 12, known as P-12, is the father of the three new kittens, as well as the father of the mother, P-19. The kittens, one male and two females, were born in the Malibu Springs area and were ear-tagged by biologists with the National Park Service last month.

The kittens are known as P-32, P-33 and P-34. P-12 is the only radio-collared mountain lion documented to successfully cross the 101 Freeway, thereby contributing new genetic material to the isolated population in the Santa Monica Mountains. He crossed near the Liberty Canyon exit in Agoura Hills, which has long been identified as the ideal location for a wildlife crossing because of the natural habitat on both sides of the freeway and its connection to vast areas of open space.

In October, a mountain lion attempting to cross into the Santa Monica Mountains was struck and killed by a car in the same location. The area is part of a critical wildlife corridor that connects the Santa Susana Mountains and Simi Hills to the Santa Monica Mountains.

Previous attempts to secure transportation funding to build an estimated $10 million tunnel under the freeway have been unsuccessful, but another round of applications is expected sometime this year. The Santa Monica Mountains Conservancy is considering funding a study that would examine a variety of solutions to address the problem.

Though the new kittens appear to be healthy, inbreeding is just one of many challenges facing the mountain lion population in the Santa Monica Mountains. The National Park Service's decade-long study to better understand how the animals survive in such an urbanized landscape shows that conflict with other lions, rodenticide poisoning and vehicle collisions are the top causes of death among more than 30 lions studied.