The McArthur Lake Wildlife Corridor in northern Idaho is a protected passage linking the Selkirk and Cabinet mountains and connecting major grizzly bear recovery zones. Its forests, wetlands, streams, and rivers support grizzly bears, elk, wolverines, lynx, wolves, moose, white-tailed deer, and rare fish, including Idaho’s only known interior redband trout populations and threatened bull trout. Yet this narrow route is also one of the state’s hardest places for wildlife to cross because Highway 2/95, rail lines, and nearby development cut through it, causing Idaho’s highest concentration of wildlife-vehicle collisions. Conservation efforts have focused on safer crossings and protecting surrounding forest from further development.