In First, Mountain Lion P-55 Crosses Back Over 101 Freeway to Return to Santa Monica Mountains

About 2 1/2 months after he crossed the 101 Freeway for the first time, a young male mountain lion has successfully ventured over those 10 lanes of divided pavement a second time.

P-55 is shown in a National Park Service photo taken April 4, 2017.

P-55 is shown in a National Park Service photo taken April 4, 2017.

The lion, known as P-55, is believed to have crossed the 101 Freeway last week, according to the National Park Service, which has been studying local cougars for 15 years.

P-55 crossed the freeway in a “relatively developed part of Thousand Oaks” west of State Route 23, the park service said on Facebook Tuesday. GPS tracking data from the animal’s collar showed his likely path.

“P-55 is full of surprises,” Ranger Kate Kuykendall said in the post.

The mountain lion, who is believed to have been born in 2015, returned to the Santa Monica Mountains after a couple months in the Santa Susana Mountains.

The crossing marked the first time wildlife biologists are aware of a mountain lion crossing the 101 Freeway twice.

P-55’s July 30 crossing from the Santa Monicas into the Santa Susanas was only the fourth such successful journey across the 101 Freeway since 2002, when the park service’s study began.

In late July, P-55 also crossed state routes 23 and 118. And he was caught on camera in the backyard of a Newbury Park home.

A National Park Service map shows the home range of mountain lions that were being tracked locally in 2016.

A National Park Service map shows the home range of mountain lions that were being tracked locally in 2016.

At that time, a federal wildlife ecologist said most GPS tracking data shows that mountain lions come to the edge of the freeway and turn around.

Research has found that mountain lions face extinction in the Santa Monica Mountains within the next half-century, in part due to inbreeding caused by geographic barriers to accessing new territory. A wildlife crossing over the 101 Freeway in Agoura Hills is planned to address this problem.

For P-55, his return to the Santa Monica Mountains means he’ll have to work to avoid other young male pumas who, like him, want to establish their own territory.

P-55 was first identified by researchers in April, along with another male big cat, P-56.