THOUSAND OAKS, Calif.— It’s been one mountain lion kitten den after another this summer for National Park Service biologists in the Santa Monica Mountains and Simi Hills. In total, 13 kittens were born to five mountain lion mothers between May and August 2020. For photos and video, click HERE
This is the first time this many mountain lion dens have been found within such a short period of time during the 18-year study, in which a total of 21 litters of kittens have been marked at the den site by researchers. Previously, the highest number of dens found in one year was four (across 10 months in 2015). Three additional litters have been found when the kittens were older (at least six months old) and had already left the den site.
“This level of reproduction is a great thing to see, especially since half of our mountains burned almost two years ago during the Woolsey Fire,” said Jeff Sikich, a wildlife biologist who has been studying the mountain lion population at Santa Monica Mountains National Recreation Area. “It will be interesting to see how these kittens use the landscape in the coming years and navigate the many challenges, both natural and human-caused, they will face as they grow older and disperse.”
Each visit to a den occurs while the mother is away hunting for food, feeding, or just resting. A biologist will track her movements via telemetry, while colleagues approach the den area. Once the den is found, the researchers will conduct the workup on the kittens a short distance away from the den. This typically takes less than an hour.
The biologists perform a general health check, determine the sex of each kitten, take various body measurements, including weight, obtain biological samples, and place one uniquely numbered and colored ear tag in each of the kittens. This tag helps to identify them in the future with remote cameras and when recaptured for the placement of a radio-collar. The kittens are all returned to the den before their mother comes back.