Welcome to Our Newest Neighbor: P-99

Mountain Lion

The LA area’s newest mountain lion, P-99, was captured and collared by National Park Service (NPS) biologists on Sept. 8, 2021 in the western Santa Monica Mountains. The 75-pound female was estimated to be two or three years old—meaning she had been pussyfooting around the mountains for years, right under the nose of researchers.

While the majority of local mountain lions being studied were first discovered as kittens still in their dens, this cool cat had somehow escaped notice until she reached adulthood.

Though P-99 was discovered in early September, news of her existence was just made public.

P-99 was anesthetized by scientists, who performed a full lab work-up that included collecting biological samples, taking morphological measurements, attaching an ear tag, conducting a physical exam and fitting her with a GPS radio collar.

The NPS has been studying mountain lions in and around the Santa Monica Mountains since 2002, in a long-term effort to learn how they survive in a fragmented and urbanized environment. NPS biologists have collared a total of 99 individual mountain lions over the past 19 years, including dozens of litters of kittens. The “99” in P-99 indicates that this is the 99th mountain lion to be captured for the study.

As of latest count, 13 mountain lions with GPS collars are being tracked in the region.

Mountain lions need sufficient prey and habitat to survive, and the NPS currently estimates that the Santa Monica Mountains can support 10-15 adult mountain lions.

The big cats face a number of challenges to their continued survival, including too much inbreeding due to inability to safely cross freeways to new territories, eating prey contaminated with rat poison, and getting hit by cars.

The world’s largest wildlife overcrossing will be built over the Ventura (101) Freeway at Liberty Canyon beginning in 2022, which is expected to help alleviate the inbreeding problem.