Over the past eight years, 535 mountain lions have been reported killed on California highways, a steady one or two a week that scientists suggest may outpace the reproductive rate of increasingly cougar clans. isolated and inbred.
“We may have reached a critical threshold: Cougars are getting killed by cars faster than they can reproduce,” said Fraser Shilling, director of the UC Davis roadway ecology center, who on Thursday released a statewide map of fatal crashes. between 2015 and 2022.
“Southern California is the undisputed capital of highways and car culture,” he said. “But state highways have turned out to be a dead end for cougars.”
To produce the map, Shilling said, mountain lion crash data was collected from CHP, Caltrans, the state Department of Fish and Wildlife, UC scientists and others, and merged into a geographic information system for visualization. .
Most of the vehicle crashes were clustered along stretches of highways and highways that extend beyond major population centers, including Southern California, the Central Coast, the Bay Area, and the western foothills of California. the Sierra Nevada mountain range.
Overall, however, the annual number of road kills involving cougars, except for 2020, when traffic was unusually low due to coronavirus stay-at-home orders, has shown a slight downward trend, while the amount of vehicle traffic was unchanged, Shilling said.
For example, in 2022, 77 cougars were killed by vehicles, compared with 92 in 2017, Shilling said.
“Those numbers could suggest that the fewer mountains there are in a given area, the less likely you are to hit one,” he added. “Anyway, every time someone dies on the road we are repeating the tragedy of the P-22.”
The legendary cougar known as P-22 roamed the hills in and around Griffith Park for more than a decade until he was struck by a vehicle and found injured in a Los Feliz backyard. State officials decided to euthanize P-22 on December 17 because he suffered from numerous health problems.
P-22 had faced a 20-mile odyssey to get from the Santa Monica Mountains to Griffith Park. The cat’s path took him over concrete and backyards, through sewers and through commuter traffic on the 405 and 101 freeways.
Free tickets to a February 4 celebration of life honoring P-22 at Griffith Park’s Greek Theater were claimed within hours of the booking window opening.
Vehicle crashes, rat poison, inbreeding, urban encroachment and wildfires are all contributing to a dire prognosis that scientists call an “extinction vortex.” There is a nearly 1 in 4 chance that charismatic cats will go extinct in the Santa Monica and Santa Ana mountains within 50 years.
The carnage plaguing cougars and other wildlife, and now causing state transportation officials to reconsider future development plans, began long before Los Angeles was known for its spidery highway systems.
The first historical record of road kills in California came from Joseph Grinnell of the UC Berkeley Museum of Vertebrate Zoology in 1920, when he became alarmed “by the number of dead animals of various kinds on the road.” He was driving a Ford Model T through Soledad Pass in northern Los Angeles County.
“This is a relatively new form of mortality,” he wrote, “and if one were to estimate the total mileage of such highways in the state, mortality must number in the hundreds and perhaps thousands every 24 hours.”
Fast-forward 103 years, and wildlife strikes are generating calls for a variety of projects designed to reduce fatal collisions while helping animals like bears, elk, deer, bighorn sheep, and cougars cross dangerous roads to find food and mates.
Cougars are not endangered in California, but in the Santa Monica Mountains, Highway 101 exists as a nearly impenetrable barrier to gene flow for a group of about 10 predators. In the Santa Ana Mountains, the 15 Freeway restricts the movement of a family of about 20 pumas.
Winston Vickers, a veterinarian at the UC Davis Wildlife Health Center, said: “It has always been a great concern that the impact of automobiles combined with other sources of mortality could be a threat to mountain lion survival, especially if a population is genetically declining. ”
Shilling’s survey comes at a time in the California Department of Fish and Wildlife’s ongoing efforts to identify and prioritize wildlife movement barriers across the state and develop plans for wildlife crossings.
Among them is the $87 million Wallis Annenberg Wildlife Crossing currently under construction on a 10-lane stretch of Highway 101 near Liberty Canyon in Agoura Hills.
Other dangerous stretches, according to Shilling and state wildlife authorities, include Interstate 5 over the Tehachapi Mountains north of Los Angeles, Interstate 15 near the Riverside County city of Temecula, State Route 91 in Orange County, State Route 74 through the Santa Rosa Mountains of Riverside County, and Interstate 8 in San Diego County.
Governor Gavin Newsom signed the Safe Highways and Wildlife Protection Act a year ago, which received bipartisan support and requires Caltrans to identify barriers to wildlife movement and prioritize crossing structures when building or improving roads .
For Shilling, such improvements can’t come soon enough. “We have basically given up on the idea of protecting wildlife if it costs us the ability to drive,” she said.
The big question now, he suggested, is this: Are we willing to do enough to protect the creatures that also have homes in California?