Designing roads with wildlife in mind is an idea whose time hasn’t come soon enough: nearly a million animals are killed on roads every day, just in the U.S., and this sobering statistic is very likely an underestimate.

“If anything, the number is probably quite a bit higher,” says podcast guest Ben Goldfarb, environmental journalist and author of the new book Crossings: How Road Ecology is Shaping the Future of our Planet.

The world is projected to build 25 million more miles of roads by 2050, so wildlife ecologists and engineers are searching for ways to integrate the needs of wildlife into their design. Goldfarb’s book offers a deep examination of some of the most fascinating, inspiring, but also tragic ways human societies develop such infrastructure alongside nature.

He joins the Mongabay Newscast to explain the concept of ‘road ecology’ and how wildlife-friendly designs are becoming part of landscapes globally.

Fueled in part by China’s ‘Belt and Road Initiative,’ the globe’s impending “infrastructure tsunami” — a term coined by eminent ecologist William Laurance — poses a threat to the planet’s ecosystems, and humanity itself.

Goldfarb’s book examines thorny questions related to human development in the contexts of climate change, biodiversity loss, social justice, and wildlife conservation. All of these intersect at the crossroads that highways have cut through ecosystems and cities.

“Over time, cars kind of became normalized…we stopped having these safety parades in cities and sort of accepted 40,000 dead Americans a year, as [the] inevitable toll of progress, and a million or more dead animals per day as the toll of progress,” says Goldfarb.

The majestic highway overpasses made for grizzly bears, elk and other animals that straddle the famous Trans-Canada Highway in Banff National Park offer some of the most arresting images of road ecology in action. Elsewhere, nations such as Brazil and India — which are leaders in this aspect of infrastructure development — are heeding the mistakes and examples of the U.S. and Canada, and are engineering infrastructure that incorporates the needs of wildlife at the outset, rather than as an afterthought.

But, as Goldfarb notes, wildlife crossings are not a catch-all solution. Much larger questions remain about how humanity will deal with the plethora of issues that roads present.

“[Wildlife crossings are] great, but they only solve some of the problems that the road creates,” he says.

Those problems include noise pollution, toxic particles shed by brakes and tires, land use change, deforestation, and the application of large quantities of ice-melting salt that poison adjacent freshwater ecosystems. Many of these issues intersect with planetary boundaries — safe operating zones that societies must heed to maintain ecologically sustainable societies — that humanity may have already crossed.

Dealing with roads is deadly, but a bit less so when built with animals in mind:

“If we want to show empathy and compassion and love to other beings, well, one way to do that is to design roads that don’t kill them.”

Related reading:

• Video: Wildlife crossings built with tribal knowledge drastically reduce collisions
• For wildlife on Brazil’s highways, roadkill is just the tip of the iceberg

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Mike DiGirolamo is Mongabay’s audience engagement associate. Find him on LinkedIn, Bluesky, Mastodon, Instagram, and TikTok.

Banner Image: A wildlife crossing over Highway 1 in Israel. Image by Hagai Agmon-Snir via Wikimedia Commons (CC BY-SA 4.0).