Discover the Epic Journey behind the Creation of Earth's Largest Wildlife Overpass, Inspired by a Solitary Mountain Lion

It sounds like the plot of a Disney movie: a mountain lion, unable to find a mate due to being trapped by L.A. freeways, rises to fame and sparks the creation of the largest wildlife overpass in the world.

But this incredible tale is a true story.

According to Beth Pratt, the California Director of the National Wildlife Federation, P-22, a cougar, managed to survive in an area significantly smaller than the average male mountain lion territory of 150 miles. P-22 gained fame among Hollywood stars who occasionally spotted him while he wandered in the neighborhoods near Los Angeles Griffith Park.

A photo of P-22 mountain lion

According to Pratt, who has commemorated P-22 on her arm through a tattoo, there was a mountain lion residing in Los Angeles that did not instill fear in the people. Rather, they perceived him as a fellow resident and would casually encounter him while having dinner, eagerly sharing photos of their encounters with P-22, as if he were a familiar neighbor passing by their dining room at night.

A career highlight for her was receiving an email from Alan Ruck, the actor from HBO's "Succession" and one of Pratt's favorite films, "Ferris Bueller's Day Off." In the email, Ruck mentioned that he spotted P-22 from the deck of his Hollywood Hills home. With P-22's popularity, there was a growing desire to assist the mountain lion and others like him in freely roaming the areas beyond the busy six-lane 101 Freeway in Los Angeles. While the concept of a wildlife overpass was generating interest, funding remained a challenge.

Pratt, who prefers the outdoors and casual attire, unexpectedly found herself surrounded by luxurious mansions in Bel Air, seeking donations. Generous contributions were received from notable celebrities like Leonardo DiCaprio, Rainn Wilson, Barbra Streisand, and David Crosby, as well as residents of Watts in South Los Angeles.

Residents in Watts view P-22 as a symbol of social justice, according to Pratt. She stated that P-22, too, has experienced the unfairness of building freeways through communities. "Whether residing in Beverly Hills or living in Watts, we all unite in our support for wildlife," she remarked.

Finding the right spot

Some 300,000 to 400,000 cars a day will pass underneath the Wallis Annenberg Wildlife Overpass when it opens in two years.

The crossing features specially crafted sound walls, complemented by towering trees and abundant foliage acting as natural sound barriers. The aim is to eliminate the disturbance caused by the freeway noise, as excessive noise tends to cause fear and deter most animals from proceeding.

A rendering of the completed Wallis Annenberg Wildlife Overpass

Courtesy National Wildlife Federation

Engineers are considering the fear of animals towards bright lights.

Pratt explained, "The intense headlights act as a deterrent for wildlife. We are actively working on designing light barriers not only on the crossing itself but also in the surrounding area to prevent animals from being startled and turning back, which is a common occurrence."

The wildlife crossing is a joint venture between the National Wildlife Federation and the California transportation department. Private donations, including a substantial $26 million contribution from philanthropist Wallis Annenberg, played a crucial role in funding half of the $100 million project. Over a span of 20 years, the National Park Service extensively investigated the precise location for the construction of the highway overpass.

"You couldnt pay me a million bucks to run across that road," Pratt said."This freeway is so big and loud and noisy and too many lights … animals dont even try."

Its not the first wildlife crossing

Wildlife crossings were first constructed in France in the 1950s. Theyre in use across Europe, and are especially popular in the Netherlands.

A wildlife overpass - "ecopont" in French - in Brignoles, France.

Martha Shade/CNN

Even animals not known for their intelligence have benefitted from wildlife corridors. In response to the significant decrease in the koala population in Queensland, Australia, caused primarily by vehicle collisions, engineers devised a network of tunnels and bridges to assist them in circumventing high-traffic areas.

However, Australian wildlife officials were skeptical that koalas, known for their relaxed behavior in trees while being under the influence of eucalyptus, would adapt to them. Therefore, these officials received a pleasant surprise when the koalas began utilizing the bridges in less than three weeks.

Meanwhile, in Canada's Banff National Park, a remarkable achievement has been made with the implementation of a series of wildlife bridges and underpasses. These corridors enable animals to safely navigate over and under the enormous Trans-Canada Highway, which divides the park.

The system is utilized by numerous large animals such as grizzly bears, black bears, moose, elk, and cougars. It is acknowledged that this system plays a vital role in sustaining the grizzly bear population by facilitating access to potential mates on either side of the park. This is precisely what needs to occur at the Wallis Annenberg Wildlife Overpass, which is located in the middle of the local cougar habitat, bisected by the freeway.

According to the Federal Highway Administration, vehicle accidents on US roads result in the deaths of one to two million large animals annually. However, Pratt argues that this number is significantly underestimated as it only accounts for reported crashes. Additionally, when considering smaller creatures like frogs and butterflies, the numbers reach into the billions.

According to Pratt, the crossings garner extensive backing as she believes, "Regardless of your political affiliation or place of residence, it is of no consequence. Majority of individuals appreciate wildlife and dislike witnessing its unfortunate demise due to accidents."

Furthermore, Pratt highlights the economic advantages that accompany these crossings. Not only do they create employment opportunities as infrastructure projects, but they also enhance human safety.

According to Pratt, it is an environmental issue with a straightforward and validated resolution, and the only obstacle to constructing it is financial resources.

"No one is to blame. We don't have to solve the technological aspects. All we require is the funding."

Rewilding an L.A. freeway

In addition to its extensive range, what sets the Wallis Annenberg Wildlife Crossing apart from other wildlife overpass systems worldwide is its unique ability to support an entire ecosystem on its surface.

A neighboring plant nursery is cultivating indigenous plants that are resistant to fire and will eventually spread across the area.

"We have been gathering seeds for several years to ensure they align with the surrounding ecosystem. This is crucial considering the climate, as both wildlife and plants require diverse choices," Pratt explained.

The removal of invasive plants, including the widespread black mustard plant, will take place in the area. Additionally, the nearby utility poles, which had to be relocated for the crossing, will now be placed underground. This will aid in fire resistance. According to Pratt, various wildlife such as mountain lions, bobcats, monarch butterflies laying eggs on milkweed, and western fence lizards residing on top will all benefit from these changes.

As part of this project, our goal is to restore the surrounding landscape, not only on the crossing itself, but also in its vicinity, to its natural state. This restoration effort will not only serve various purposes but also mitigate the risk of wildfires."

P-22, the cougar who played a crucial role in inspiring the creation of the wildlife crossing, will unfortunately not have the opportunity to utilize it. Tragically, in December 2022, just a few months after the National Wildlife Federation and California's transportation department initiated the construction of the bridge, P-22 passed away.

Pratt acknowledged that while his passing was a heart-wrenching event, the truth remained that he had lived a considerably lengthy life for a mountain lion.

"Yet, beyond his longevity, he leveraged his fame for noble purposes. I deem him the unparalleled influencer among cougar celebrities."

She expressed that his story guaranteed a prosperous future for the mountain lions residing in the area.

"We are immensely grateful to him, as he has served as the catalyst for the creation of the Wallis Annenberg Wildlife Crossing. Without his influence, this remarkable project would not have come to fruition."