“The lives of wild animals are defined by mobility. You have all of these different scales, both spatial and temporal, in which animals are moving. They’re moving daily, as they roam around their territories looking for food. They’re moving seasonally, as they migrate between different habitats as the year turns. They have to move, in some cases, once in a lifetime, to disperse through new territory, or in search of a mate.
All of those movements are absolutely imperative to the survival of both individual animals and wildlife populations. Roads terminate or truncate those movements, by killing animals directly, as roadkill, but also by creating a barrier of traffic, what some researchers call a “moving fence” — this kind of impenetrable obstacle that prevents animals from navigating their habitats. To take a really dramatic, stark example, there are herds of mule deer and pronghorn in Wyoming that starve en masse while trying to reach low-elevation valleys to find food in winter because highways have blocked their migrations.”
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“One of the really eye-opening experiences that I had working on this book was taking part in some bicycle surveys of roadkill in Montana. When you’re rolling along at 10 miles an hour and you’re much lower to the ground, rather than seated in the captain’s chair of an SUV, you see all of those small lives that you would never see at highway speeds in a car. I was struck by how many birds we saw: raptors, magpies, ravens, songbirds. The avian life along the side of the highway was really, really visible.”
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“Hearing is one of the most important senses that wild animals have. It’s absolutely imperative for both predators and prey.”
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“Wildlife crossings are incredibly effective, paired with roadside fencing that guides the animals to the crossings.”
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“For the most part, the wildlife crossings that we’ve built are aimed at large, common animals that endanger driver safety, like deer and elk and moose: the animals that will wreck your car and maybe end your life if you hit them. We need more of those. But we also need more crossings that benefit the animals that don’t kill drivers on a regular basis, especially reptiles and amphibians, which are some of the most road- and car-endangered groups of animals in the world.
There are turtle culverts and toad tunnels out there, but they’re few and far between. There’s a lot of focus on wildlife crossings that pay for themselves, that prevent enough car crashes to recoup their own construction costs. But I think we’re also starting to see the rise of wildlife crossings that are aimed at conservation, rather than cost savings.”
https://www.vox.com/future-perfect/23868483/cars-roads-roadkill-crossing-goldfarb-national-parks