3 Bobcat Kittens Found Inside Calabasas Oak Tree

CALABASAS, CA — Calabasas has three new residents, and their names are B-379, B-380, and B-381.

The new residents happen to be bobcat kittens, who were born to a female bobcat captured and collared about a year after the Woolsey Fire. On April 15, National Park Service biologists found the three kittens and their mother, B-370, living deep inside the cavity of a large oak tree, in an area of the mountains badly scarred by the Woolsey Fire.

“[Bobcats] typically have their dens in areas that are thick brush, like chaparral, or coastal sage vegetation - they also like to use woodrat nests, which are like large piles of sticks and leaves,” Ana Beatriz Cholo of the National Park Service told Patch. “But because of the Woolsey Fire doing so much damage to the land here, that took away a lot of their habitat, so the bobcats are being resourceful.”

The Woolsey Fire destroyed close to half of the natural area in the Santa Monica Mountains, and about ⅔ of the natural habitat in the Simi Hills, according to the NPS.

In April, NPS biologists suggested that B-370 was denning because she repeatedly returned to the same spot, an indication that a female has likely given birth, according to an NPS news release. Biologists used VHF radiotelemetry and GPS points from B-370’s collar, but couldn’t initially find her.

“I swear she’s in this tree, but I can’t find her,” biologist Joanne Moriarty recalls saying to a colleague. “Then I look up into this tiny hole in the tree, and her face is just poking out at me. Of course, she’s been staring at me the whole time. I just happened to be in the right spot.”

Moriarty used a remote camera on an extension pole to peek into the tree and confirm the presence of a bobcat and three kittens - two males and one female who were about 30 days old at the time. The next day, while the mother was hunting, a team of biologists crawled down a ladder to capture the kittens, who were weighed, measured, and given a general health check. The kittens came in at 5-600 kg, or just over a pound each.

They were also ear-tagged for the purpose of future identification, before being released back into their dens.

Kittens typically stay in the natal den for four to five weeks, and then the family will move on to other dens that they use for shorter periods. Researchers speculate this may be to avoid predators. Mothers typically keep kittens inside dens until they’re 12 weeks old, when they join her on hunting excursions.

B-730 was initially found in the Simi Hills, and biologists took hair and tissue samples and fitted her with a collar to track her movements. Researchers usually deploy 6 to 12 traps between October and February to monitor the population, and then release them into the wild.

2020 was an unusually prolific year: in September, National Park Service biologists reported that five mountain lion dens containing a total of 13 kittens have been discovered in the Santa Monica Mountains and Simi Hills between May and August of 2020, marking the first time in an 18-year-study of the species that so many dens have been found within such a short time.

See also:

• 13 Mountain Lion Kittens Discovered During The 'Summer Of Kittens'
• Liberty Canyon Crossing Gets $25M Challenge Grant From Wallis Annenberg