For at least a decade Los Angeles nature lovers have been enamoured by P-22, a mountain lion that, much to the surprise of wildlife biologists, moved into a popular urban park at the eastern end of the Santa Monica Mountains in 2012. Over time, he became something of a celebrity in L.A. as well as an ambassador for urban wildlife and the urgent need to protect remaining wild spaces. After many years of prowling the urban fringes of Los Angeles's mountainscapes, the famous cat's reign has come to a close.

P-22's celebrity status helped raise awareness about the plight of LA's mountain lions.

A recent erratic change in P-22's behaviour and a handful of incidences involving attacks on pets prompted wildlife officials to capture the celebrity feline and assess his condition. He was found to be suffering from several long-term health concerns as well as injuries that may have been the result of being hit by a car. A tough decision was made yesterday to humanely euthanise the ailing cat.

"It’s been an incredibly difficult several days," Chuck Bonham, director of the California Department of Fish and Wildlife told the LA Times. "And for myself, I’ve felt the entire weight of the city of Los Angeles."

Indications that P-22 may have been in a bad state came earlier this month when he began to show "signs of distress," which included close encounters with people walking in Los Feliz and Silver Lake, as well as three separate attacks on pet dogs.

Wildlife officials darted and captured the big cat in a backyard in Los Feliz on Monday night in order to assess his condition. A day earlier, an anonymous caller reported a vehicle collision with a puma in the area near where P-22 was found raising suspicions that he may have been struck by a car.

A thorough medical evaluation undertaken by a team at the San Diego Zoo Safari Park showed significant trauma to the mountain lion’s head, right eye and internal organs. In addition to the injuries, P-22 – thought to be about 12 years old – was also found to have kidney disease, chronic weight loss, a parasitic skin infection over his entire body, and localised arthritis. All of this would have been too much for the elderly cat to survive.

A closeup of P-22 taken some years before his condition began to significantly deteriorate.

"This situation is not the fault of P-22, nor of a driver who may have hit him," The California Department of Fish and Wildlife stated in a press release. "Rather, it is an eventuality that arises from habitat loss and fragmentation, and it underscores the need for thoughtful construction of wildlife crossings and well-planned spaces that provide wild animals room to roam."

In his lifetime, P-22 became a symbol for the conservation of urban wildlife as well as a cautionary tale about the dangers of overdevelopment and exploitation of the environment. The fact that P-22's home range became fragmented by LA’s extensive road network made him the perfect 'poster cat' for a mammoth effort to construct the world's largest wildlife corridor over one of the busiest highways in California – the ten-lane 101 north of Los Angeles.

After years of campaigning and fundraising by the Save LA Cougars , ground was finally broken on the construction of the overpass in April this year raising hope that the fragmentation of Los Angeles puma population (as well as that of other wild species) will be lessened. 

At the heart of the campaign was an extraordinary cat that, despite the odds, eked out an existence in the long shadow of human development. 

"He changed the way we look at LA. And his influencer status extended around the world, as he inspired millions of people to see wildlife as their neighbours," said Beth Pratt, a conservation leader with the National Wildlife Federation who spearheaded the corridor campaign.

P-22 first exploded onto the Hollywood scene when his tawny rump turned up on a remote camera trap in Griffith Park. wildlife biologists initially assumed the cat would move on in search of more suitable habitat where he could also potentially find a mate. But this was no ordinary puma. P-22 stayed put, usually slinking undetected through the park's hillsides and canyons and occasional turning up on doorcams of homes on the fringes of his urban habitat. 

The famous cougar was "an iconic ambassador for wildlife in Los Angeles," said Miguel Ordeñana, a science communicator at the Natural History Museum of Los Angeles County and the biologist who first found P-22 on a camera trap photo. "His passing is a painful moment, but we are so thankful for how he created a better understanding of the coexistence of urban wildlife, humans and LA’s biodiversity. His story is a catalyst for change."

P-22's full story and the role he played in inspiring the creation of a species-saving wildlife corridor is portrayed in P-22: The Cat That Changed America. You can stream it here: