Moosehorn National Wildlife Refuge is one of the northernmost National Wildlife Refuges in the Atlantic Flyway, a migratory route that follows the eastern coast of North America. The refuge provides important feeding and nesting habitat for many bird species, including waterfowl, wading birds, shorebirds, upland game birds, songbirds, and birds of prey. The refuge consists of two divisions. The Baring Division covers 20,016 acres and is located off U.S. Route 1, southwest of Calais, Maine. The 8,735-acre Edmunds Division is between Dennysville and Whiting on U.S. Route 1 and borders the tidal waters of Cobscook Bay. Each division contains a National Wilderness Area, thousands of acres managed to preserve their wild character for future generation. The East Coast Greenway, connecting Calais, Maine to Key West, Florida, runs through part of the refuge.
On the edge of the refuge next to US Route 1 are platforms erected for nesting bald eagles.