Another LA Mountain Lion Has Mange And Biologists Suspect Rat Poison

Female mountain lion P-53 was treated for mange last month. Biologists with the National Park Service's Santa Monica Mountains National Recreation Area suspect she was exposed to rat poison. (Courtesy National Park Service)

A mountain lion in the Santa Monica Mountains is suffering from mange, a rare but possibly fatal skin disease, and National Park Service biologists suspect the cougar was exposed to rat poison.

P-53, a 3 ½-year-old female, was re-captured in February after researchers monitoring her on remote cameras saw signs of the disease, caused by parasitic mites in animals' hair and skin.

Biologists treated her with a topical medication, fitted her with a GPS collar and released her back into her home range, according to Kate Kuykendall, spokeswoman for the Santa Monica Mountains National Recreation Area (SMMNRA).

"It's concerning to see this mange in a mountain lion, because it generally means that the animal is compromised in some other way such as having been exposed to toxicants," said Seth Riley, a wildlife ecologist with SMMNRA and adjunct associate professor at UCLA. "We are hopeful the treatment will be successful and that we can monitor P-53's recovery through remote camera images."

P-53's diagnoses marks the fifth recorded mange case among the park's mountain lions. In the previous cases, Kuykendall noted, two pumas "died from uncontrolled bleeding as a result of anticoagulant rodenticide poisoning." Another was treated and believed to have recovered — but was found dead over a year later. The other recent case was L.A.'s most famous mountain lion, P-22, who was treated in 2014. The celebrity cat later bounced back to a healthy state.

All four of those infected pumas had anticoagulant rodenticide (aka rat poison) in their system, Kuykendall said. Researchers are awaiting test results to confirm that P-53 was also exposed to the compound.

Mange is usually rare in wild cats, Kuykendall said, though the bobcat population in the Santa Monica Mountains has been experiencing an epizootic (the animal version of an epidemic) of the disease since 2002, leading to a "significant population decline."

NPS researchers said 17 of 18 local mountain lions they've tested have been exposed to rat poison, including in a three-month-old kitten.

What most likely happens, according to biologists, is mountain lions are exposed through "secondary or tertiary poisoning," meaning they eat a smaller animal that had ingested the poison, or a smaller predator that previously ate poisoned prey.

"Exposure to these toxic compounds can lead to unchecked internal bleeding and death," Riley said in a previous news release. "This kind of poisoning was the second leading cause of death in our coyote study and continues to be a significant source of mortality and disease for bobcats and mountain lions."

Of course, this whole thing is really our fault. Local wildlife wouldn't be exposed to rat poison if humans weren't using those poisons in and around our homes.

That's why park officials and their friends group launched an awareness campaign last year to educate the public about the threat to animals further up the food chain and inform residents about alternative pest control options.

This story is part of Elemental: Covering Sustainability, a multimedia collaboration between Cronkite News, Arizona PBS, KJZZ, KPCC, Rocky Mountain PBS and PBS SoCal