Just west of Helena, Montana, Highway 12 climbs from the valley of the Missouri River towards the Continental Divide. The landscape changes from open grassland to hills covered with lodgepole pine and Douglas fir forests. Highway 12 rounds a tight, hairpin turn before breaking out into the open expanses of MacDonald Pass and dropping over the other side of the Divide. Each year, tens of thousands of people drive their cars, trucks, motor homes and other vehicles through this scenic area without realizing that it is one of the most important places for wildlife in the entire Yellowstone to Yukon region. This map shows why:

The green area on the map is National Forest land. These public lands are part of the network of core areas and wildlife movement corridors that provide habitat for key wildlife species like grizzly bears, wolves, lynx and wolverine. To the north of Highway 12 (the red line extending across the middle of the map) these public lands connect to Glacier National Park and its surrounding Wilderness areas. To the south, these public lands extend all the way to Yellowstone National Park.

Photo: Wendy Francis

Here at MacDonald Pass (where Highway 12 intersects with the Continental Divide, the dotted line running from north to south down the middle of the map) the public lands narrow to less than two miles wide. On either side are expanses of private lands that are vulnerable to development with subdivisions and roads. Wild animals need the security of trees, shrubs and bushes to remain hidden from sight by humans and other predators. So they will tend to use the forested public lands for their travels. The two-mile width of the National Forest lands at MacDonald Pass creates a “bottleneck” of vulnerability for these creatures.

Not only does the narrow width of forest lands here create a risk to wildlife, the highway itself is also a major source of wildlife death. Mule and white-tailed deer, bears of both species, elk, moose, coyotes, mountain lions and others are all present in the area and have been the victims of collisions with vehicles.

In addition to the narrow wildlife movement corridor and the threat of speeding vehicles, other challenges face animals that use MacDonald Pass. The Montana Army National Guard is proposing to establish a biathlon facility close to the pass. The sport complex would include the construction of several assorted buildings, an access road and a parking lot for about 50 vehicles. Clearing and thinning of trees would occur on about 30 acres. The project currently is on hold because of an inadequate environmental assessment.

MacDonald Pass is a great example of how the Yellowstone to Yukon vision helps to shine a spotlight on an area that otherwise might be seen as a local issue only. Because of the priority of reconnecting grizzly bear populations in the Greater Yellowstone Ecosystem with those in the Northern Continental Divide, the public lands on either side of MacDonald Pass assume a much greater significance. Ensuring the ability of bears and other animals to cross over Highway 12 safely is important to the ecological health of animals far away from this one mountain pass.

Defenders of Wildlife and American Wildlands are two Y2Y partner groups that are working to raise awareness of the importance of MacDonald Pass and to prevent new threats from even further weakening this tenuous but important link for wildlife in the Yellowstone to Yukon region.