Wildlife Corridors: Conserving Nature’s North-South Highway
To research my book, The Spine of the Continent, one of the first things I did was to get out a map. Wow—stretching more than 3,000 miles from Alaska down to Mexico, and visibly shaping nearly half the landmass, the Rockies amply illustrate the Native American (Miistakis) term for these mountains, “the backbone of the world.”
The Spine of the Continent is a geographic, social, and scientific effort to sustain linkages along the Rockies so that plants and animals can keep moving.
Movement is at the heart of what keeps nature going, and human impacts—like housing developments, roads, oil and gas drilling—interrupt this movement. Watch a Bighorn sheep look at a fence and wonder what the heck to do about it, and you get the picture. All sorts of animals and plants need to move to maintain genetic viability, and to fulfill migrational and territorial imperatives. The boundaries around our national parks have given us wonderful jewels like Yellowstone, but science tells us this approach is inadequate. National parks are simply not big enough to sustain healthy nature; wild places need to be connected to each other.
Climate change has brought another dimension to this need for “connectivity.” Protecting connections between wild places will allow animals and plants to move to the temperature zones they are adapted to, as these shift up slope. Climate change provides another strong incentive for protecting biodiversity. When nature is healthy, it buffers the impacts of fire, drought, and major weather events. Healthy nature bounces back more quickly, which will also help us recover from these onslaughts.
During my research for the book, I trekked through wilderness in gorgeous and beguiling places, including Waterton Lakes National Park and Glacier National Park in Canada and Montana; Rocky Mountain National Park in Colorado; the Manti-LaSal National Forest in Utah; and the Sky Islands in Arizona and Mexico. In Canada and Mexico it was easy to see plentiful evidence of the critters who call the landscapes home—their tracks criss-crossing river beds, signs of predation including bits of fur and pieces of bone, and, in the case of grizzly bears, huge indentations in the vegetation where they had likely been napping. There is less sign of wildlife between Canada and Mexico, because there is less of it here.
As I traveled along, I meditated on the very idea of travel, for humans and for wildlife. Referring to my map of North America, I plotted out my routes by air, by train, and by car, and with hiking guides I figured out where to go on foot, how far. The plants, animals, and people who first inhabited this continent came across the Bering Strait and down the Spine of the Continent; wildlife still uses this North-South route to disperse, to find mates, to hunt—the Spine is truly their life-line. By contrast, however, most of our roadways are oriented East-West. One effect of this cross-purpose is to bifurcate natural pathways, in many cases stranding wildlife on either side of them.
This is exactly the sort of thing the Spine of the Continent landscape initiative is working to ameliorate. Wonderful people all along the Spine are doing heroic things to help keep nature connected. They are working with officials to build highway overpasses and underpasses, to restore watersheds, to monitor how wildlife, like pika, are doing as the climate changes.
North, South, East, West. Nature travels the landscape, like people do. We can figure out how to be better traveling companions to the critters who sustain us by keeping natural systems healthy. What route are you taking?