Red Rock Lakes Wilderness in southwest Montana protects most of the Red Rock Lakes National Wildlife Refuge along the western edge of the Greater Yellowstone Ecosystem. Set aside to strengthen protection for lakes, marshes, and wetlands, it became closely linked to the survival of the trumpeter swan, as more than half of the estimated 69 birds remaining in the lower 48 states by the mid-1930s were found here. The refuge was an early effort to save a disappearing species, and the later wilderness designation added stricter habitat safeguards. Today the area supports abundant birdlife and mammals, while management under the 1964 Wilderness Act prohibits roads, motors, logging, mining, and camping within the wilderness.