
By Steve Gorman
LOS ANGELES (Reuters) – Mountain lions have been dying on California highways at least once or twice a week for the past few years, a toll that may exceed the healthy reproductive levels of the big cats, new animal mortality data showed on Thursday in the wild. .
The Road Ecology Center at the University of California (UC) at Davis has released maps showing deadly highway crossings — which are most heavily clustered in Southern California, the San Francisco Bay Area and the western foothills of the Sierra Nevada.
The data adds to research showing that mountain lions, also known as cougars or cougars, are under increasing pressure from traffic and urban sprawl that are causing their territories to become increasingly isolated from each other, shrinking their gene pools.
“Over time, additional deaths from cars, especially for small, isolated populations, add significantly to the threats they already face, Fraser Shilling, the director of the Road Ecology Center, said in releasing the latest maps.
A well-known example was the Los Angeles area mountain lion named P-22, a cougar with a radio collar who became a celebrity in the wild after managing to cross two busy highways to take up residence in the Hollywood Hills around Griffith Park.
P-22’s demise came after the cat, a male believed to be 12 years old, was hit by a car and injured. Conservationists captured and euthanized the lion in December after a medical examination revealed that P-22 was severely weakened by several ailments.
“P-22’s tenacity in life and the final tragedy of his death from a vehicle collision highlights the plight of mountain lions across California, under constant threat from traffic as they go about their natural lives,” Shilling said.
Another cougar with a radio transmitter, P-81, was found dead last month after a possible collision with a vehicle in the western Santa Monica Mountains.
The study cataloged a total of 535 cougar deaths on some 15,000 miles of state-run highways over eight years, from 2015 to 2022. That number adds up to nearly 70 per year, but researchers said the true toll likely would be higher if city and county roads were included.
The death rate was also found to have fallen by about 10% over the past seven years. But the trend suggests cougar populations are gradually declining as the rate of highway deaths matches reproductive rates, researchers said.
Publicity surrounding P-22, famously photographed sneaking past the landmark Hollywood sign, helped raise funds for the world’s largest wildlife overpass, spanning U.S. Highway 101 near Los Angeles. The project started last April. A public celebration of P-22 is scheduled for Saturday in Griffith Park.
(Reporting by Steve Gorman in Los Angeles; editing by Sandra Maler)