In the legal world, it'd be called circumstantial evidence.
On March 3, one of the Los Angeles Zoo's koalas went missing. Down the road from its enclosure, a tuft of its hair was found. About 400 yards farther down, zookeepers made a grisly discovery: bloody marsupial parts.
Something must have been able to carry it that far, park employees figured. So they examined the park's "trap cameras" — surveillance devices with motion sensors — in an effort to spot the culprit. Though the attack wasn't recorded, they did find still photos of the likely perpetrator: P-22, Griffith Park's famous mountain lion.
Zoo officials don't know how the mountain lion is getting in and out of the park, but said it was spotted on cameras stationed around the zoo the night the koala was killed.
For the Record
March 10, 5:41 p.m.: A previous version of this article identified Beth Pratt-Bergstrom as California director of the National Wildlife Foundation. It is the National Wildlife Federation.
The zoo also released a black-and-white video taken by surveillance cameras placing him near the scene the night before the koala was discovered missing.
"The evidence is circumstantial. We don't have any video of it taking the koala. We can't say 100%," L.A. Zoo director John Lewis told The Times on Thursday.
About a month ago, cameras stationed around the park to record the behavior of smaller wild animals, like bobcats and coyotes, roaming the park at night showed P-22 also on the premises.
"It was kind of like 'Whoa,' " Lewis said when they saw the 6-year-old puma on camera.
P-22 has been seen on camera a few other times since then, and once left the remains of a devoured raccoon in its wake. Sometime between the night of March 2 and the morning of March 3, the predator visited the koala enclosure, Lewis thinks.
That's where it probably found Killarney, the oldest koala in the exhibit at 14 years old, on the ground, unprotected from the elevation the trees provide. Koalas live to be 12 to 15 years old, Lewis said.
"She was very individual," Lewis said of the koala, which had no offspring and hailed from Australia. "At night, for whatever reason, it was typical for her to walk around. … The other koalas were up in the trees."
There was no blood trail in the enclosure, and no fur to indicate a violent attack, he said. The koalas were kept in an open enclosure surrounded by an 8-foot high wall.
"He had to jump down into the enclosure and jump back out with the koala," Lewis said of the predator. "It's a pretty good feat in itself. ... It was a pretty quick snatch."
Employees noticed something was amiss the following morning when they conducted a koala head count. There were only 10, when there should have been 11.
Killarney weighed 15 pounds and arrived at the zoo in May 2010. She was born Dec. 17, 2001, Lewis said.
"Unfortunately, these types of incidents happen when we have a zoo in such close proximity to one of the largest urban parks in the country," Barbara Romero, deputy mayor for City Services, said in a prepared statement.
"We are investigating the circumstances of the koala's disappearance, but in the meantime, we are taking action to ensure that all of our animals are safe. The koalas have been removed from their public habitats for now, and other animals are being moved to their night quarters when the zoo closes," she said.
If P-22 was behind the attack, it wouldn't be a complete surprise, National Park Service official Kate Kuykendall told NBC4.
"This wouldn't be an example of him behaving aggressively or abnormally," she said. "Whether it's exotic pets or exotic animals, or our own domestic pets, we need to make sure they're in safe enclosures or brought in at night."
City Councilman Mitch O'Farrell took a different tack. In a statement released to local media outlets, he suggested it was time for P-22 to find a new home.
"Regardless of what predator killed the koala, this tragedy just emphasizes the need to contemplate relocating P-22 to a safer, more remote wild area where he has adequate space to roam without the possibility of human interaction," O'Farrell said.
"P-22 is maturing, will continue to wander and runs the risk of a fatal freeway crossing as he searches for a mate. As much as we love P-22 at Griffith Park, we know the park is not ultimately suitable for him. We should consider resettling him in the environment he needs," he said.
But City Councilman David Ryu, whose district includes Griffith Park, rejected the suggestion that P-22 should be relocated.
"The incident at the Los Angeles Zoo is incredibly unfortunate; however, relocating P-22 would not be in the best interest of protecting our wildlife species," Ryu said in a statement. "Mountain lions are a part of the natural habitat of Griffith Park and the adjacent hillsides."
P-22 has become somewhat of a mascot for Griffith Park, with his majestic image captured in front of the Hollywood sign by a National Geographic wildlife photographer.
Last year, the mountain lion caused an only-in-Los Angeles scene — complete with TV news trucks lining the street — when he padded out of Griffith Park and took refuge in the crawl space under a Los Feliz home. He eventually wandered back into the park.
State and federal wildlife experts are investigating an uptick in reports over the past year of mountain lions feasting on pets, hobby animals and livestock in and around the Santa Monica Mountains National Recreational Area.
Genetic testing from UCLA and UC Davis showed that P-22 was probably born in the Santa Monica Mountains and then crossed the 405 and 101 freeways to make Griffith Park his home in 2012.
"I've told the zoo and other land owners with animals, it is their responsibility to protect those animals with full enclosures and proper fencing," said Jeff Sikich, a National Park Service biologist and expert on local mountain lion populations.
"Otherwise," he added, "these mountain lions are being rewarded with free meals by simply going into pens where animals can't run or hide."
Zoo officials have added even more cameras since last week's attack to see whether they can find how P-22 is getting into the park, Lewis said.
The koalas are kept with western gray kangaroos in a tree-laden enclosure, around the corner from a concession stand called the Churro Factory and across from the Tasmanian devils.
On Thursday morning, there were no signs of the tragedy. However, there also were no signs of koalas.
Beth Schaefer, a zoo curator, said the creatures were being kept indoors for protection. It was unclear when they would be returned to their habitat.
"Koalas don't like change," she said. Zookeepers are monitoring the survivors' behavior, making sure they're eating and sleeping OK. "So far, so good," Schaefer said.
Word of Killarney's demise surprised those who visited the zoo early Thursday.
"Our immediate reaction was, 'That's so sad,' " said Rose Scobie, 32, of Monterey Park.
Scobie and a group of other mothers were visiting the zoo with their toddlers.
Michelle Liu, 36, of Monterey Park, said the children were too young to understand what had happened, but they were going to visit the enclosure regardless.
"We're going to go pay our respects," she said.
The California director of the National Wildlife Federation called a mountain lion living in Los Angeles "something to celebrate."
"Mountain lions are called ghost cats for a reason," Beth Pratt-Bergstrom said. "They are solitary animals that want to be left alone. P-22 lives in an urban park visited by millions of people and is rarely seen, demonstrating what we already know—it is possible to peacefully coexist and the risk of danger is very low."
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