Los Angeles mountain lions becoming more nocturnal to avoid humans, study finds
Griffith Park’s late celebrity mountain lion P-22 worked the night shift to avoid the hordes of hikers, bikers and hangers-on who frequented his home in downtown Los Angeles, According to a new study, this pattern has been replicated by other cougars in the area.
Researchers at UC Davis and other institutions conducting the study said the delayed timeline is an encouraging example of a species doing its part to coexist in a bustling metropolis.
But experts say the time gymnastics they perform can come at a cost, draining energy and limiting the time they can spend on critical tasks like hunting. It can also exacerbate other urban stresses, such as whizzing traffic and rat poison.
The study, published last month in the journal Biological Conservation, found that Southland mountain lions became more nocturnal and less active at dusk or dawn in popular recreational areas.
To study the impact of recreation on lions, the researchers used GPS and activity data collected from the tracking collars of 22 mountain lions that roamed the Santa Monica Mountains and surrounding areas between 2011 and 2018.
They also took data from Strava, a popular app where users publicly record runs, hikes and other activities, to determine how much recreational activity occurred within each lion’s home range and test how well it Affects its activity patterns and timing.
The “most nocturnal” cougar in the study was the late P-41, who lived in the Verdugo Mountains, a recreational haven bounded by highways and development on the northeastern edge of the San Fernando Valley. Second on the list is P-22, affectionately known as the Brad Pitt of Mountain Lions when he stalks the Hollywood Hills.
Studies have shown that female lions are less nocturnal than male lions, possibly because male lions pose a threat to them and their kittens.
(AP National Park Service)
Researchers wondered whether mountain lions exposed to more recreational activities would become immune to it and simply not care.
“We saw the opposite,” said lead author Ellie Boras, a doctoral student at the University of California, Davis.
“I think seeing how mobile and recreational mountain lions are, we can be optimistic that they are willing to avoid us and want to avoid us,” she added.
Other participating institutions include Cal Poly Pomona, the National Park Service, UCLA, the University of Nebraska and Harvard University-Westlake High School.
The discovery is good news for Angelenos worried about becoming a lion’s lunch — because cats are avoiding humans. This helps explain how apex predators can successfully invade it in dense urban environments. Los Angeles is just one of two major cities in the world home to big cats. The other one is Mumbai, India, where there are leopards wandering the streets.
So why are local lions rearranging people’s schedules? The new study suggests that animals may fly to less populated areas when possible. But in the Los Angeles metropolitan area, which has a population of more than 18 million, even natural areas are mired in traffic jams. So they adopted another strategy.
The National Park Service has monitored lions in and around the Santa Monica Mountains for more than 20 years, which was the source of the long-term data for the recent study.
“One of the important things we’ve been studying is the impact of urbanization and fragmentation on these animals,” said study co-author Seth Reilly, wildlife division chief of the park’s Santa Monica Mountains National Recreation Area. Riley) said service.
The new study shows that, contrary to the researchers’ expectations, lions’ temporal shifts were not significant during weekends, when recreational activity is at its peak.
There are also differences between the sexes, with female mountain lions being more active during the day and closer to sunrise. Researchers speculate that they avoid overlapping with male lions, who kill kittens dragging them along and sometimes even kill female lions.
The least nocturnal cougar tracked is P-13, a female cougar whose habitat is in central and west Santa Monica.
Beth Pratt, executive director of the National Wildlife Federation’s California region, said while it’s good news that these charismatic cats are “coping”, there may be trade-offs.
“By changing their hunting strategy, it’s not ideal,” said Pratt, one of the P-22’s biggest supporters. “It takes more energy and doesn’t give them a lot of options, but the animals here are doing their part.”
People should also participate by minimizing challenges, she said. Black panthers stalking the Santa Monica Mountains face the danger of inbreeding because highways essentially lock them in, while tourists with the needed genetic diversity are locked out.
“At some point, they’re not going to be able to handle all these challenges that are piling up,” she said, referring to threats like cars and rodenticides — both of which have taken a toll on the P-22. He was captured and euthanized in late 2022 because he was deemed too ill to return to the wild due to injuries and infections.
Platt said one way to give lions an “advantage” is to build wildlife crossings.
The Wallis Annenberg Wildlife Passage, currently under construction at a cost of more than $90 million, is seen as a potential lifeline for Santa Monica’s lions. Without an exit, people risk collapse.
Pratt says the new research shows that seemingly innocuous behaviors, such as how we choose trails and enjoy the outdoors, can have an impact on species – and it’s necessary to consider our approach when dealing with the biodiversity crisis .
“It’s not that we shouldn’t do it, but how do we do it differently so the animals don’t suffer,” she said.
Porras said there are no studies showing whether the flexibility in lions’ activity time also comes at a cost to them, but “it’s very likely it is.”
The study’s findings come as some mountain lions in Southern California and the Central Coast are at a crossroads.
California wildlife officials are preparing to decide whether to designate six isolated tribes of mountain lions as endangered or threatened species under state law.
In 2020, the state Fish and Game Commission granted temporary endangered status to mountain lions that roam between Santa Cruz and the U.S.-Mexico border as candidates for listing under the state’s Endangered Species Act.
A final decision is expected next year.
