Proposed Freeway Passage Routes Would Keep Cougars From Cars

Before construction of the 101 and 118 freeways, mountain lions roamed undeveloped space from Malibu to the Los Padres National Forest.

Now the freeways present unintentional barriers that have isolated cougars in the Santa Monica mountains from the larger mountain lion population to the north, leading to inbreeding when the imperiled animals do not attempt to cross, and sometimes death when they do, according to Kate Kuykendall of the National Park Service.

Since systematic record keeping of cougar deaths on roadways began in 2002, there have been 14 deaths, including a mother lion and one of her cubs in two separate incidents last month on the 118 Freeway in the Santa Susana Pass.

There may be as few as 15 cougars in the Santa Monica Mountains National Recreation Area south of the 101, the park service estimates, and the future survival of cougars in this area is imperiled. It's believed the outlook would improve through natural breeding with animals roaming from the north.

"That movement is really crucial to bring new genetic material south of the 101 Freeway," said Kuykendall.

The width of the 101 and suburban development from the West San Fernando Valley to the Conejo grade evidently have proved intimidating to cougars, and few attempt to cross. As a solution, the Parks Service has proposed a wildlife bridge at Liberty Canyon, and is now working on plans with the overseer of California's freeways, Caltrans. Wildlife advocacy groups, meantime, are attempting to raise $10 million this year to keep the project moving forward.

Last month, the predatory slaughter of 10 alpacas at a ranch in the Santa Monica Mountains was attributed to one of the cougars, designated P-45. Mountain lions are protected by California law, but "depredation" permits may be issued to kill cougars that cause damage. The owner of the ranch, Victoria Vaughn-Perling, revealed that she had received a permit, but decided not to exercise it.

Cougar mapping shows a corridor that leads north from Liberty Canyon through undeveloped hills to the Santa Susana Pass between Chatsworth and Simi Valley. From there, remaining barriers to the Los Padres are less daunting.

In Kuykendall's view, the 118 Freeway presents a different challenge than the 101, because more mountain lions attempt to cross it.

As it turns out, there may be no need to build a wildlife crossing for the 118, because there is already a tunnel below the freeway in Corriganville Regional Park on the Simi side of the pass.  The tunnel was intended for hikers and equestrians, not wildlife, and it appears that only rarely over the years has a mountain lion discovered it. A camera did record P-3 taking the tunnel a decade ago.

Kuykendall sees need to develop ways to steer cougars to the tunnel, and at the same time discourage them from attempting to cross the freeway. She thinks the answer will include animal fencing alongside.

That would be under the authority of Caltrans, and it is prepared to discuss the issue with the park service, though at this point there are no plans to add animal fencing, said Yessica Jovel, a Caltrans spokeswoman.

Among those applauding steps to facilitate mountain lion crossing is Ric Alviso, who was driving home on the 118 on Dec. 3 when he spotted the body of P-39 at the edge of the freeway's far right lane. It appeared to him that the cougar was hit while trying to cross from north to south.

"It's definitely worth investing some money," said Alviso, describing wildlife as "precious," and seeing mountain lions as part of a local ecosystem that should be protected.

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