2nd Mountain Lion Kitten Killed on Freeway

This article is based on material from City News Service and the National Park Service

An 8-month-old female mountain lion was struck and killed by a vehicle on a stretch of freeway just outside Los Angeles where its mother and brother were fatally struck last month, the National Park Service announced Friday.

The kitten, known as P-51, was found dead Jan. 14 along the the 118 Freeway one mile east of the Rocky Peak exit, according to the NPS. The kitten's mother, P-39, was killed on the same stretch of freeway Dec. 3, and her brother, P-52, was killed on the roadway Dec. 20.

The dead kittens were part of a litter of three mothered by P-39.

The death of P-51 was the 17th known case of a mountain lion killed on a freeway or road  in the National Park Service study area around the Santa Monica Mountains since 2002.

"Unfortunately this case illustrates the challenges for mountain lions in the region, where roads are both major barriers to movement and potential sources of mortality," said Seth Riley, wildlife ecologist for Santa Monica Mountains National Recreation Area. "The area where these animals were killed is part of a critical wildlife corridor that connects the genetically isolated population in the Santa Monica Mountains to what is considered the nearest source population, in Los Padres National Forest."

The California Department of Fish and Wildlife Investigations Lab examined the body of P-52 to determine his overall health, especially because he had been without his mother since she was killed a few weeks earlier. At seven months, mountain lions can cover a significant amount of area, but it is unclear to what extent they can survive on their own. They found that P-52 was thin, weighing 24 lbs., but still had adequate internal fat reserves. Additionally, he had fed recently on a skunk - a typical prey item for a kitten learning to hunt.

“It was positive to see that P-52 had recently fed,” said Marc Kenyon, CDFW’s Mountain Lion Conservation Program Coordinator. “Whether or not these kittens had the ability to feed was a subject of much discussion. Apparently, their mother had taught them predatory skills within their first six to seven months, and we’re hopeful the tests on P-51 confirms this, too.”

Despite the fact that more deaths have occurred on this stretch of the 118, the stretch of the 101 freeway on the northern edge of the Santa Monica Mountains is considered more of a long-term threat to the viability of mountain lions in the region. NPS researchers have documented multiple mountain lions crossing the 118 numerous times, indicating it is less of a barrier than U.S. Highway 101. The fact that it is somewhat easier to cross has led to many more attempted crossings on the 118 than on the 101, resulting in a greater number of deaths. 

A hiker/equestrian tunnel that has occasionally been used as an undercrossing is located near where the deaths occurred, but the area lacks adequate wildlife fencing to direct animals to the tunnel.

“Caltrans is aware of the need to protect the biological diversity of the region. To that end, we are working with our partners to study the feasibility for wildlife passage and protection,” said Carrie Bowen, Caltrans District 7 Director.

Southern California’s extensive road network has been shown to be a major barrier for wildlife and has particularly hemmed in the mountain lion population in the Santa Monica Mountains. A proposed wildlife crossing on the 101 in Agoura Hills would provide a connection between the genetically isolated population in the Santa Monica Mountains and the robust populations to the north.

The National Park Service has been studying mountain lions in and around the Santa Monica Mountains since 2002 to determine how they survive in an increasingly fragmented and urbanized environment.