2 Mountain Lions Found Dead in Santa Monica Mountains

Rebekah Sager
October 08, 2019 - 10:55 am



Two mountain lions were found dead in the Santa Monica Mountains, one a healthy six-year-old male (P-30) and the other was (P-53).  The cause of death is determined to be anticoagulant rodenticide poisoning, say the National Park Service biologists. 

Biologists hiked to Topanga State Park on September 9, after P-30's collar sent a mortality signal. He was found dead with no signs of injury or trauma. The California Animal Health & Food Safety (CAHFS) Laboratory field office in San Bernardino revealed that he bled to death internally. The report documented that he had severe hemorrhaging in his brain and abdominal cavity. Approximately five liters of unclotted blood was found in his abdomen.

Park officials say this is the fifth mountain lion to die by pesticide. 

“Just about every mountain lion we’ve tested throughout our study has had exposure to these poisons, generally multiple compounds and often at high levels,” said Seth Riley, an ecologist and the wildlife branch chief for Santa Monica Mountains National Recreation Area (SMMNRA). “A wide range of predators can be exposed to these toxicants - everything from hawks and owls to bobcats, coyotes, foxes, and mountain lions. Even if they don’t die directly from the anticoagulant effects, our research has shown that bobcats, for example, are suffering significant immune system impacts.”

P-30 was re-captured in February 2018 and given a new GPS collar. He is one of the more notable mountain lions of the study because he was the first male lion kitten to have been marked at the den and then to have survived long enough in the Santa Monica's to reach adulthood and establish a home range.

Previous remote camera photos had indicated that P-53 likely had mange, a condition caused by microscopic parasitic mites that burrow deep into the skin and cause severe itching, hair loss, and skin lesions. NPS consulted with veterinarians and disease experts with the California Department of Fish and Wildlife. When P-53 was recaptured in February of this year, upon confirming her mangy appearance, biologists treated her with selamectin, a topical treatment for ectoparasitic diseases such as mange, fleas and ticks.