MALIBU—Officials confirmed on Wednesday, September 7, that a pregnant mountain lion that was found dead off Las Virgenes Road this summer tested positive for multiple anticoagulant rodenticides commonly known as rat poison. The fetuses the mother lion carried also tested positive for the poison. 

The actual cause of death was traumatic injuries, including multiple fractures to the ribs and left femur. The lion known as P-54 was five years old when she was found dead between Piuma Road and Mulholland Highway at around 9:30 a.m. on June 17. She was struck by a vehicle. 

P-54’s body was taken away to undergo a necropsy where scientists found four different compounds in her system. The compounds brodifacoum, bromadiolone, chlorophacinone, difethialone, and diphacinone were found in her liver and also in her abdominal fat tissue. 

“This is the first time during our 20-year study that we’ve been able to test mountain lion fetuses for anticoagulant rodenticides,” said Jeff Sikich, a biologist on the mountain lion project at Santa Monica Mountains National Recreation Area, a unit of NPS. 

“A primary goal of our work is to learn whatever we can about these animals and how their lives are affected by the urban landscape they inhabit. Unfortunately, we’ve learned that mountain lions are susceptible to rat poisons even before they are born,” Sikich said. “In this case, it is also unfortunate because the death of P-54 from a vehicle resulted in the loss of four other young mountain lions, two males and two females, that were about to enter the population.” At the time of P-54’s death, all her cubs were at full-term. 

Canyon News reached out to the LASD Malibu/Lost Hills Sheriff’s Station for more information, but did not hear back before print.