Look out – a new type of cougar is showing up in suburbia. In 2021, a home security camera caught a cougar prowling a Los Angeles residential neighborhood. Under the cover of darkness, the cougar navigated a dangerous maze of highways and city streets, roaming miles from her wild territory. Many of these urban cougars meet a sad end: they are hit by cars.
Adult North American cougar (Puma concolor)
Only 23% of land worldwide remains unmodified by the direct impact of human activities. What land remains untouched is heavily fragmented. Habitat loss is the number one cause of species extinction, and habitat fragmentation amplifies this threat. The future of wildlife, climate change or not, depends on improving habitat connectivity. We need to bridge the gap between conservation and restoration. Sometimes the answer is as simple as building a bridge.
Near LA, the Wallis Annenberg Wildlife Crossing is under construction. This vegetative overpass will connect the Simi Hills and the Santa Monica Mountains over a ten-lane freeway, allowing mountain lions and other wildlife to cross safely. This is part of a broader strategy sweeping the nation. Wildlife corridors connect fragmented habitats and facilitate the movement of wildlife between them.
Webs of streets and highways split habitats into many pieces. Roads pose an enormous hazard for roaming wildlife. Each road is a potentially fatal barrier for animals. Many animals don’t have a choice. They must cross roads to find food, shelter, and habitat — just like the cougars of LA County.
Every road is a challenge. Some animals might not take the chance. Bears aren’t likely to cross a six-lane highway. If they can’t find enough food on this side of the road, household trash may become an easier target.
Even when animals do attempt to cross, many don’t make it to the other side. One of deer’s top predators is cars, and one of cars’ top predators is deer. Roadkill comes in all shapes and sizes; from squirrels and possums to deer and mountain lions. All are sacrifices to the machines we’ve built our infrastructure around. We’re driving wildlife to their graves.
Without wildlife crossings, roads are more dangerous for everyone involved. Each year in America, collisions with large animals result in 200 deaths, 26,000 injuries, and $8 million in damages. Now, I’ve never hit a deer, and maybe you haven’t either. But the chances aren’t as low as you might think. On average in the US, drivers have a 1 in 115 chance of collision with an animal each year. In West Virginia, the chance is 1 in 35.
Today’s transportation infrastructure isn’t equipped to handle wildlife movement. But that can change. In places of known wildlife movement, wildlife crossings have reduced animal collisions by up to 97%!
The US has implemented a number of wildlife crossing projects. Along Highway 93 in Northern Montana, 41 wildlife crossings were constructed with coordination between the Confederated Salish and Kootenai Tribes and State and Federal Highway Administration. The project was designed to respect the tribe’s belief that “the road is a visitor and that it should respond to and be respectful of the land and the Spirit of Place.”
The project was surprisingly successful. Following the project’s completion, over 53,000 individual animal crossings were recorded over the course of two years. Over 30 species were documented crossing, including black and grizzly bears, mountain lions, bobcats, white-tailed and mule deer, elk, river otters, and turkeys. One study found that the most effective of the 41 crossings reduced motorist-animal collisions by nearly 100%!
Camera trap photo of black bears (Ursus americanus) using a wildlife underpass to cross US Highway 93.
There are a number of wildlife crossing projects that you can support today. The I-90 Wildlife Corridor Campaign is working to reconnect Washington’s north and south Cascades with crossings. Those that are already built are being used by mountain lions, bears, and even the elusive wolverine.
Since the Bipartisan Infrastructure Bill was passed, there is new funding specifically aimed at wildlife safety. The law’s Wildlife Crossings Pilot Program will distribute $350 million in grants to tribal, local, state, and regional agencies for crossing projects. To support these projects, advocate for wildlife crossing construction to your State Department of Transportation, or write to Secretary of Transportation, Pete Buttigieg, on the issue.
And since building wildlife bridges takes time, also consider donating to wildlife conservation and rehabilitation centers in your area – they’ll do their best to assist the victims of our faulty infrastructure. And perhaps most importantly, drive carefully!