Animal Crossing: World’s Largest Wildlife Bridge Hits California Freeway | Wildlife
Iimagine driving down a 10-lane highway and knowing that, high above your head, a mountain lion is quietly following its path. This remarkable image could soon become reality for drivers on one of California’s busiest roads, as construction on the world’s largest wildlife overpass begins this month.
The historic project will include a green bridge built over the 101 Freeway near Los Angeles, creating a corridor between two parts of the Santa Monica Mountains. Stretching 210 feet long and 165 feet wide, the overpass will allow safe passage for lizards, snakes, toads and cougars, with an acre of local plants on each side and vegetated sound walls to dampen light and noise for nocturnal animals as they glide through.
The project, which has spanned nearly a decade, comes at a crucial time. The highways of this car-heavy landscape criss-cross critical habitat for protected mountain lions and other animals, forcing them to make crossings that can be deadly. At least 25 of the big cats have been killed on Los Angeles freeways since 2002. The latest fatality was just weeks ago, on March 23, when a young lion was struck and killed on the South Coast Freeway. Peaceful.
Beth Pratt, an urban ecologist at the National Wildlife Federation, feels like running the last mile of a marathon. Pratt has spent most of the past decade planning the project, persuading transportation officials of its importance, and rallying stakeholders and donors to fund it. “I’m still a little dizzy, but I feel relieved: we have the chance to give these cougars a chance for the future.”
A groundbreaking ceremony to mark the start of construction of the $90 million crossing – called the Wallis Annenberg Wildlife Crossing – will take place on Earth Day, April 22. Construction will take place mainly at night and the project is not expected to be completed until early 2025.
Approximately 60% of the cost of the bridge will be covered by private donations, with the rest coming from public funds earmarked for conservation purposes. California Governor Gavin Newsom called the project “an inspiring example” of public-private partnership.
“A symbol of connection”
The project breaks the mold in many ways: not only is it the world’s largest crossing, spanning 10 lanes of one of the busiest roads in the country, but it’s also an engineering marvel. . The traverse is designed to fit seamlessly into the mountains, providing big cats, coyotes, deer, lizards, snakes and other creatures a safe way to get to different parts of the open territory of the Santa Monica Mountains Recreation Area – an area of 150,000 acres.
Robert Rock, a landscape architect with Living Futures in Chicago who led the design, says this type of nature-centered construction makes it unusual among other bridges and underpasses around the world, which are usually made of cement and steel. This is designed to seamlessly slip into the environment on both sides – and send a message to people driving below.
His team includes a soil scientist – who collected local tree-specific samples nearby – and a mycologist, who studies the fungi in the area and how they can help with the continued movement of plants and animals through the viaduct. Guides will be posted nearby to discourage people from exploring the viaduct. (Pratt says planting poison oak and posting signs about rattlesnakes are also effective tools for keeping humans off the bridge.)
Rock says he’s optimistic the investment could set a precedent for how design can play a restorative role in the natural world. “As a tool and symbol of connection, it will be an alluring challenge for future generations to pick up the torch of design to fill the gaps elsewhere in our world,” he said.
About 300,000 cars pass through this area every day, and Pratt calls it an opportunity for millions of Angelenos to see how humans can live more harmoniously with nature. “Someone might be in rush hour traffic, and there might be a mountain lion right above them,” she says. “I think it’s such a hopeful and inspiring picture that we can right some of these great wrongs.”
Pratt says the plight of the region’s mountain lions has drawn the attention of donors around the world. People were sending money from London. A Kansas couple who had only visited the city once donated $675,000. Leonardo DiCaprio’s foundation raised $300,000. Pratt points to the famous local puma P22, whose exploits around town have made headlines, as the catalyst for it all. “People really took his plight to heart, and it’s not just a California story: the world has rallied around his cause.”
P22 won’t actually be the intended user of this crossing, as he lives in a part of Los Angeles on the far eastern side of the mountain range. But its symbol has raised the funds that will finance the bridge. And most of the 100 cougars in the area live in the area the bridge will span.
Scientists say there is a learning curve for the animals and they will slowly begin to explore the bridge. For suspicious creatures, it can take up to five years to successfully use traversal. Cats will follow smaller prey species, which generally adapt faster to new territory.
“It’s not just a solution for P22 to cross the road, as much as P22 is the face of the campaign,” Rock explains. “It’s about restoring a lost piece of habitat, putting it back through the mountains.”
More projects to come
Wildlife crossings are accelerating across the country and the world. They make economic sense – most pay for themselves within a decade or two, and a study in Banff, Canada, whose national park has more than 40 wildlife underpasses and overpasses, found a 90% decrease in collisions between wildlife and vehicles, which saved the park money.
But it’s only recently that the wildlife science and infrastructure communities have come together to understand the problem in depth. Joe Biden’s $1.2 billion infrastructure bill included $350 million for animal-friendly infrastructure such as bridges, underpasses and roadside fencing.
Pratt says the project struggled to raise funds early in the planning. Fortunately, the team was able to find people who recognized the importance of this project.
But perhaps the biggest challenge was philosophical: Opponents told him the project shouldn’t or couldn’t be done – “that we shouldn’t waste money saving mountain lions in an urban area, that we could never raise the funds.” She was not discouraged. “I wasn’t going to take no for an answer, not when a mountain lion population was at stake.”