Mcarthur Lake Wildlife Corridor
Animals occasionally travel long distances. Sometimes these travels are to seek unoccupied suitable habitat, or perhaps to seek mates. They usually try to use travelways that are similar to their preferred habitat when they are not travelling. If possible, they try to avoid areas that have high concentrations of humans. That's why certain areas are considered key connection corridors by wildlife biologists.
McArthur Lake, about halfway between Bonners Ferry and Sandpoint, Idaho, is such a key corridor. It is the shortest distance between the Selkirk Mountains and the Cabinet and Purcell Mountain ranges for hundreds of miles north or south. If you look on a map with elevation lines showing ridges and valleys, you can see that there is a mere 5 miles of rural valley bottom between these two mountain ranges. In one study of wildlife corridors in Idaho, about 1/3 of the areas identified as important corridors were considered high priority. McArthur Lake is one of these high priority corridors.
Very few valley bottoms in the world are without some type of human development. The McArthur Lake Wildlife Corridor is no exception. There are homes and farms present there, and most of the residents use their land for natural resources such as timber harvesting or agriculture. For the most part, these uses of the corridor are compatible with the wildlife that may choose to either pass through or make their homes there. Also present in the same narrow strip of land are a major natural gas pipeline and an electrical powerline.
The most impactive feature of the corridor is the presence of a major highway, US Highway 95, and two major international railroads. Average daily traffic on the McArthur Lake to Elmira stretch of US Highway 95 is 4,600 vehicles. Elmira to Naples has average daily traffic of 3,800 - of these vehicles, about 13 percent of them are commercial carriers over 26,000 pounds (Idaho Transportation Dept., 1998).
The two railroads and the highway are a major hazard to all species of wildlife crossing them. While many animals do cross safely, hundreds are killed each year in collisions with automobiles, trucks, and trains. These collisions are a safety hazard to people, cause huge amounts of property damage, and needlessly reduce the wildlife resource in the area.
Highways and railroads represent a less visible issue to animals, too. There are several species of shy animals that avoid the noise and lights of heavily used roads and railroads. These animals are prevented from joining other individuals of their species, possibly resulting in what wildlife biologists call a restriction in "gene flow". Frequently, these shy animals are also rare, such as lynx, grizzly bears, or wolverines.
