SCOTT SIMON, HOST:
A mountain lion known as P-22 became famous when a photo of him in front of the Hollywood sign appeared in the December issue of National Geographic. Recent news that P-22 had become ill from exposure to rat poison has heightened concerns about the use of rodenticides in California. Gloria Hillard has more.
GLORIA HILLARD, BYLINE: In the hills above Hollywood, Dr. Seth Riley, a wildlife ecologist with the National Park Service, sits in his truck tracing a map of Griffith Park.
DR. SETH RILEY: So we're at the observatory here, but we're going on Mount Hollywood Drive.
HILLARD: He's on the trail of a mountain lion named P-22. Griffith Park is home to an abundance of wildlife, but P-22 is its most famous four-legged resident, having crossed two of the busiest freeways in the country - the 405 and the 101 - to get here.
RILEY: And then, 101 - boy, it's hard to even imagine.
HILLARD: After P-22 was sighted in the Park two years ago, biologists captured him and fitted him with a GPS collar. Wearing headphones, Riley walks to the side of the road and slowly moves in a half circle holding a directional antenna. After a few minutes, he hears a signal.
(SOUNDBITE OF GPS SIGNAL)
RILEY: So he's right down in this - the bottom of this drainage here. Right below us here.
HILLARD: In March, Riley was part of the team that recaptured P-22 after a remote camera showed that the mountain lion had become ill.
RILEY: It was hard to - you know, to have to see him sick like that.
HILLARD: He was weak and suffering from mange, believed to be the result of exposure to rodenticide or rat poison. For two decades, scientists with the Santa Monica Mountains National Recreation Area have researched the exposure of rodenticides to wildlife up the food chain, from smaller first-target rodents to coyotes and bobcats to birds of prey.
RILEY: Back in 2004, we had two mountain lions that also died - just like the coyotes were dying - of bleeding to death internally from rodenticide poisoning. Interestingly, they - those two mountain lions also had mange. They didn't have it as badly as the bobcats get it before the bobcats die of it.
HILLARD: L.A. County's Department of Public Health requires the city's Department of Recreation and Parks to suppress ground squirrel populations. Principal Forester Laura Bauernfeind says the bait stations are used in very limited areas, and that the parks department isn't the only user of the poison.
LAURA BAUERNFEIND: The bigger thing to take into consideration is the fact that so many rodenticides - first- and second-generation - are available to the general public on the shelves at Home Depot and Lowe's. And you have to remember that Griffith Park is surrounded by hundreds and hundreds of homes.
HILLARD: State regulators recently banned the sale of what is considered the more powerful second-generation anticoagulant rodenticides from the retail shelf. But they will still be available to licensed pest control companies. California assemblyman Richard Bloom has offered a bill which would ban the poisons in state and national parks throughout California.
ASSEMBLYMAN RICHARD BLOOM: There needs to be a solution to rodent infestation. But when the solution ends up killing and severely injuring the health of the predators of the rodents, then we've got a real problem on our hands.
(SOUNDBITE OF GPS SIGNAL)
HILLARD: When biologists recaptured the sickly P-22 in March, they treated him for the mange and injected him with vitamin K to try and counteract the effect of the rat poison. Recent photos of P-22 show his health has improved some. But wildlife ecologist Seth Riley says, there are concerns the mountain lion is still at risk for re-exposure.
RILEY: You know, all these species - two-thirds of them are exposed to multiple compounds. So they're clearly asked being exposed, you know, multiple times.
HILLARD: Of equal concern, P-22's adopted home is pretty small for a mountain lion, and he may try to make his way back to the Santa Monica mountains in search of a mate. That could mean navigating streets and freeways again. In the meantime, P-22 seems content to keep out of sight from humans. On this day, probably taking a nap under the shade of the brush - heard, but not seen. For NPR News, I'm Gloria Hillard.
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