Three Reasons to Support Wildlife Overpasses and Why

An adventure through Canada’s Banff National Park brings musings on saving wildlife through man-made bridges.

When driving through the Canadian Rockies, one is struck by several things, all at once (which makes driving difficult):

• The mountains are really, really big (h-u-u-u-ge)
• The landscape is so heart-achingly stunning, it is hard to focus — first, there are fields! Then endless pine forests! Then craggy glacial mountains! Rivers full of smooth tumbled rocks!
• And, there are these bridges…but not for cars…

The bridges are what I’d like to focus on because they are really, really cool. (The mountains are also cool and you can read more about how they help us calm down in the post below.)

Glacial Pep-Talk: How to Talk to Rocks & Calm Down

Car-less Bridges

So these car-less-bridges. What’s up with that? Why? To pass under them is to realize that they are large and well-engineered. Indeed, they cost upwards of $3 million per structure (!!). They look landscaped, in a way: trees and grass growing on top, boulders strewn around the base. But they’re not for cars! Or even, as it turns out, people.

They’re for the animals.

Why is this important?

1. They save wildlife from being annihilated by moving vehicles
2. They serve as a literal bridge, connecting migration corridors
3. They help maintain genetically healthy populations among wildlife

A saving grace for wildlife

As you may be aware, cars are sort of deadly, particularly for wildlife. It turns out that wildlife is not so accustomed to metal boxes ripping through their homes on top of flat, blacktop at excessive speeds. It’s also worth noting that the laws of physics don’t really help this situation. Collisions between vehicles and animals generally end in unfortunate circumstances. Who would have thought?

It also turns out that the highway we were traversing through this stretch of the Canadian Rockies lies within Banff National Park — a protected wildlife area that also happens to have a major highway artery running right through it. And as late as the 1990s, there was nothing to prevent wildlife from wandering across this stretch of road to meet an untimely demise.

Roadkill reality

Growing up on the east coast of the US and as someone who has spent many hours driving across interstate highways (8-hours to grandparents and parents’ friends; 11 hours to university, and on and on) I became accustomed to seeing roadkill. It was a fact of life (or death?).

Everywhere you drive on highways in New Hampshire, New York, Maine, Pennsylvania, Vermont (and on and on) you are likely to spot some unfortunate animal who was on the receiving end of a brutal lesson in the laws of physics. Dead raccoons, foxes, deer, birds, and even dead cats (I know, I know). What you see less of is the impact this has on human populations, too. Vehicle run-ins with large ungulates like moose and elk can be catastrophic for all parties.

I assumed this was normal; sad and unnecessary and awful…but normal.

What is normal?

You may imagine my surprise then when I came to BC and learned of Canada’s efforts to protect wildlife: including wildlife overpasses!

These overpasses are most prevalent in Alberta, tucked in Banff National Park, but other mechanisms for keeping animals from vehicular traffic are obvious everywhere. High deer fencing is ever-present along many major highways. And it’s clear that it works. I recall being surprised at not seeing flattened animals along the highways — so much so, that when there is the occasional accident between a Ford and Fauna, it’s notable and jarring.

Isn’t that something?

And if you think that this is a bunch of malarky and that wildlife overpasses sound preposterous (how will an animal even find it? They can’t possibly be that smart!) think again.

Among large carnivores, mortality rates are 50 to 100 percent lower along sections of the highway where overpasses and underpasses exist. In those same sections, mortality rates for elk are almost zero, compared to 100 elk-vehicle collisions per year in the mid-1990s. Clevenger’s research has shown that 11 species of large mammals in Banff have used the structures more than 200,000 times, including unexpected species such as red fox, hoary marmot, boreal toads, wolverines, lynx, garter snakes and beavers. — Canadian Geographic

Not a new concept

Fortunately for wildlife, the idea of preserving species through engineered mechanisms is not new. The concept for a wildlife overpass first came to fruition in France in the 1950s! Since then, the idea has taken hold in countries all over the world, from Canada and the US to Belgium, China, and beyond.

The benefits of a wildlife overpass go beyond simply saving wildlife from meeting an untimely demise. They also serve as literal corridors, connecting species with migration pathways, and actually enhancing genetic diversity (can you believe that?!).

The idea took a little longer to catch on in the United States, but wildlife bridges and tunnels began appearing there in the 21st century. — National Geographic

Where to place the value?

Roadkill and maimed wildlife are the direct results of a system that undervalues our wild spaces.

The idea is not without opposition, though. Over (or under-) passes are expensive and they take time to implement. And, often it’s not just the overpasses that are required. Typically, fencing along a highway is also set up, to funnel wildlife towards a safe crossing structure (be it an overpass or underpass). This requires more time and more investment.

This begs the question: how do we place value on a thriving, abundant ecosystem? That it isn’t the first priority of municipalities or corporations to protect and enhance wildlife, is the sad reality of our world. All you have to do to understand this priority is go for a drive anywhere where there aren’t exclusion fences or any kind of over/underpass for wildlife.

Roadkill and maimed wildlife arethe direct results of a system that undervalues our wild spaces.

So what can we do?

If this whole thing feels as big as the Canadian Rockies, don’t worry! There are some things we can all do to help propel the idea of wildlife overpasses forward:

1. Get this issue in front of your elected official: last year in the US, the Biden administration allocated $350 million toward the development of wildlife crossings (these include overpasses but also other structures like tunnels for salamanders!! What!)
2. Learn more from groups and researchers dedicated to progressing this cause — like the Center for Large Landscape Conservation and the Western Transportation Institute, among others.
3. Keep an eye toward the future: innovations are being made to create flexible solutions to wildlife overpasses. Literally, they are bendy!
4. If you see a wildlife crossing in your travels, snap a pic or record a video and share it! This idea is not new and the more people who know about it, the more likely it is that we’ll all get pumped up about it enough to do Step 1. ;-)