Now, here’s a graphic illustration of the importance of wildlife corridors. Impressive . . .
Step off Montana Highway 200 at Rogers Pass, hop on the back of a wolverine, and you would cross pavement just three times before reaching Banff, Alberta.
Two of those roads, U.S. Highway 2 and Going-to-the-Sun Road, cross the otherwise blank spot on an unusual map that’s been floating around the Internet recently. The map, assembled by Reddit user WestCoastBestCoast94, displays virtually all the nation’s roads – and nothing else. The resulting black-and-white representation of the Lower 48 tends to get one common response:
The United States has about 4 million miles of public roads. According to federal highway statistics, 97 percent of the continental U.S. is less than three miles away from a road. Eighty-three percent lies within half a mile. A recent analysis prepared by the Western Transportation Institute at Montana State University looked at the unroaded areas of Montana, Idaho and Wyoming – three states with the least population density short of Alaska – and found that 16 percent of their combined territory qualified as essentially roadless. The study included national parks, which do have some roads.
Some more support for the importance of biological and botanical corridors and other efforts to reduce habitat isolation . . .
An extensive study of global habitat fragmentation — the division of habitats into smaller and more isolated patches — points to major trouble for a number of the world’s ecosystems and the plants and animals living in them.
The study shows that 70 percent of existing forest lands are within a half-mile of the forest edge, where encroaching urban, suburban or agricultural influences can cause any number of harmful effects — like the losses of plants and animals.
The study also tracks seven major experiments on five continents that examine habitat fragmentation and finds that fragmented habitats reduce the diversity of plants and animals by 13 to 75 percent, with the largest negative effects found in the smallest and most isolated fragments of habitat.
Rob Breeding talks about the importance of wildlife corridors by contrasting the Northern Rockies with the tenuous situation in California . . .
When we visit my hometown of Riverside, Calif., my daughters and I like to get some exercise running Mount Rubidoux, a semi-famous landmark in this part of the world. In the winter, especially when the smogless skies get an extra scrubbing from the Santa Ana winds, Mount Rubidoux offers unobstructed 360-degree views of Southern California’s Inland Empire.
You can’t quite see the Pacific from here, but that’s because the Santa Ana Mountains get in the way. Those mountains are where one of my old grad school profs, Paul Beier of Northern Arizona University, used radio collars to show how mountain lions use even the thinnest thread of connectivity to move between habitat islands created by encroaching suburbia. Even narrow culverts running beneath urban freeways are used by traveling wildlife.
On a clear day as I run I can see dozens of these habitat islands scattered across the Inland Empire. I distract myself from my workout by recreating in my mind the wildlife wonderland this natural landscape must have been before it became prime human habitat. I know there were valley quail everywhere, which is enough to get my attention.