The Detroit River International Wildlife Refuge is the only international wildlife refuge in North America. Established in 2001 and managed jointly by the United States Fish and Wildlife Service and the Canadian Wildlife Service, it is located in a major metropolitan area. The Detroit River International Wildlife Refuge is one of over 540 National Wildlife Refuges managed by the U.S. Fish and Wildlife Service within the Department of the Interior. It occupies 7.88 square miles (20.41 km2) of scattered property but has drawn boundaries for further expansion.