Lake Mason National Wildlife Refuge is located in the center of the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

. The refuge has numerous lakes and extensive marshlands along Willow Creek, which provide nesting habitat for over a hundred bird species. Managed from the Charles M. Russell National Wildlife Refuge

Charles M. Russell National Wildlife Refuge

Charles M. Russell National Wildlife Refuge surrounds Fort Peck Reservoir and at 1,100,000 acres is the largest refuge in Montana, United States. Created in 1936, the refuge was named after famed painter of the American West, Charles M. Russell...

, the refuge is normally unstaffed and has few visitor improvements. The refuge is also divided into several separate sections, all of which form an integral part of the Charles M. Russell National Wildlife Refuge Complex

Charles M. Russell National Wildlife Refuge Complex

Charles M. Russell National Wildlife Refuge Complex consists of six National Wildlife Refuges, all of them managed by the U.S. Fish and Wildlife Service. The refuges are located in the central sections of the U.S. state of Montana. The complex includes the following areas:*Charles M...

.