The female and male mountain lion will spend a few days traveling together prior to the birth of kittens. Females can breed with multiple males during an estrus cycle, a recurring period of sexual receptivity and fertility in many mammals. The gestation period for mountain lions is about 90 days and they can breed and give birth at any time of year.
Females can have their first litter at two to three years old and will raise their kittens for one to two years, after which point, they will breed again. Adult males do not help in the rearing of kittens.
Each visit to a den by a biologist 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 a full workup on the kittens a short distance away from the den and place them back at the den when finished. This typically takes less than an hour.
The biologists perform a physical exam, 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.
A total of 22 litters of kittens have been marked at the den site by our researchers. Four additional litters have been found when the kittens were older (at least 6 months old) and have already left the den site (as of December 2021).
P-019 bears the distinction of being the oldest mountain lion mother in our long-term study and the mountain lion we have tracked for the longest time. We have been following her practically her entire life when she was first captured and implanted with a tracking device in May 2010 when she was only a few weeks old.
Following individual animals for their entire lives is one of the benefits of a long-term study like this, and it provides unique and valuable information about the challenges to survival for mountain lions in the area.
The first mountain lion mother to be studied in the Santa Monica Mountains, P-002 died at the claws of her mate, P-001, in the summer of 2005. Intraspecific conflict (cougar-on-cougar fighting) is common to the species and one of the leading causes of death for mountain lions in our area.
Last updated: January 19, 2023