Mountain lion P-54, who was struck by a car and killed in the Santa Monica Mountains early this summer, was pregnant with four full-term kittens when she died, National Park Service officials announced Wednesday. That makes her death an even bigger blow for those concerned about the area’s dwindling mountain lion population.
“The devastating death of P-54 and her four unborn kittens is a morbid reminder that we are driving our beloved pumas towards extinction,” said Tiffany Yap, a senior scientist at the Center for Biological Diversity.
Park officials said tests also revealed that P-54 and all four of her unborn kittens had rat poison in their systems when they died.
It’s the first time in the 20 years the park service has been studying mountain lions in the area that they’ve been able to test fetuses for anticoagulant rodenticides, which can cause rats — and animals connected to them in the food chain, from hawks to foxes to mountain lions — to internally bleed to death. And the news wasn’t good.
“Unfortunately, we’ve learned that mountain lions are susceptible to rat poisons even before they are born,” said Jeff Sikich, a biologist on the mountain lion project at Santa Monica Mountains National Recreation Area.
One category of rat poison — second-generation anticoagulants — has been banned for consumer use in California since 2014, based on the documented risks these poisons pose to wildlife and pets.
But when the consumer ban was established, the state allowed licensed pest control companies to continue using them. And, four years later, the state reported that second-generation anticoagulants still were showing up in 90% of tested mountain lions, 88% of tested bobcats and 70% of tested northern spotted owls. Between the summer of 2018 and spring of 2019 alone, the deaths of four Southern California mountain lions were linked to rat poison.
In fall 2020, California passed Assembly Bill 1788. With exceptions for some medical and food production facilities, the law permanently banned the use of second-generation anticoagulants in wildlife settings. The law also temporarily banned their commercial use everywhere else, pending the results of studies still underway by the Department of Pesticide Regulation.
But first-generation anticoagulants and other forms of rat poison are still widely permitted. And biologists say the results from P-54 and her kittens show that exposure to rat poisons is still widespread.
Like almost every other mountain lion tested in and around the Santa Monica Mountains, park service officials said they found anticoagulant rodenticide compounds in P-54’s liver. The five-year-old lion had been exposed to five types of anticoagulants, plus a neurotoxin called bromethalin.
The animal’s unborn kittens — two boys and two girls — also tested positive for at least three anticoagulants. And National Park Service researchers have now documented these toxins in 39 out of 40 local mountain lions tested, including the four fetuses.
Officials say the death of P-54 highlights two of the most dangerous elements for local wildlife: toxicants and vehicles. She was killed June 17 on Las Virgenes Road between Piuma Road and Mulholland Highway. After her body was taken to the California Animal Health and Food Safety Lab in San Bernardino, researchers determined her cause of death to be traumatic injuries, including multiple fractures to the ribs and left femur.
Seven mountain lions in the study area have been hit and killed by cars since January, making 2022 the deadliest year on record for mountain lions being hit by vehicles, according to Ana Beatriz Cholo, spokeswoman for the park service.
Since the park service started its study, 20 years ago, Cholo said 32 mountain lions have died in the area. The most recent was found two weeks ago, when two-year-old P-90 was hit and killed on a highway in Ventura County — just weeks after his brother was fatally hit on a nearby freeway.
Four years ago, P-54’s mother was hit and killed on the same road where she died in June. And in April, P-54’s 18-month-old son was killed by a car on the 405 freeway near the Getty Center. He’d only recently struck out on his own.
Yap said the news sheds fresh light on the need for Assembly Bill 2344, which would require transportation agencies to study and plan for wildlife passages that would reduce vehicle deaths and keep animal habitats more connected. The bill “would be a big step towards protecting these iconic cats,” Yap said.
The bill passed the legislature in August and is now waiting on Gov. Gavin Newsom’s signature.
Construction is already underway on the $87 million Wallis Annenberg Liberty Canyon Wildlife Crossing in Agoura Hills, which will give mountain lions and other wildlife safe passage over the 101 freeway. That project is expected to be complete in 2023.