About Us

Green Bay National Wildlife Refuge is made up of several islands located in Lake Michigan, between Wisconsin’s Door County Peninsula and Michigan’s Garden Peninsula (also known as the Grand Traverse archipelago).

The refuge is made up of:

  • Plum Island - 325 acres
  • Hog Island - 2 acres
  • Pilot Island - 3 acres
  • St. Martin Island - 1,260 acres that are managed by the U.S. Fish and Wildlife Service (not entire island)
  • Rocky Island - 10 acres
  • A parcel of land on Detroit Island - 148 acres

These islands act collectively as “steppingstones” for migrating birds, bats and butterflies as they cross along this section of the Niagara Escarpment - limestone that stretches in a wide arc from eastern Wisconsin through Michigan’s Upper Peninsula, across Ontario, Canada and on through the Niagara Falls in New York.

Long before European settlement in Wisconsin, several different Native American tribes occupied and traversed the islands now known as the Grand Traverse Islands. Located in northern Door County, Wisconsin and southern Delta County, Michigan, this island chain enabled otherwise distant tribes an opportunity for safer travel and trade among Lake Michigan’s treacherous waters. The waters between the mainland of Door County and Plum Island hold the legendary Native American name of Death’s Door, later called Porte des Morts by French trappers and traders. The name Death’s Door was given after a failed battle attempt between tribes over hunting grounds on the mainland. One tribe lost nearly 20 canoes full of warriors as they were swept by Lake Michigan’s ferocious waves and unpredictable winds into a rocky cliff shoreline (Vroman, 2007).

Plum and Pilot Islands

Plum and Pilot Islands have played a significant role in the maritime history of Wisconsin. In 1849, the first lighthouse was placed on Plum Island’s south shore, but by 1858 it was determined that the light would better serve mariners from Pilot Island, so the Plum Island light was abandoned, and the Pilot Island light constructed. By 1896 ship traffic in Lake Michigan and Green Bay had become so prevalent that a set of front and rear range lights and other structures had to be built on Plum Island. The maritime structures were managed by two separate services, the United States Life Saving Service and the United States Lighthouse Service. Eventually, the two services merged into what is the present-day United States Coast Guard. Through time, water levels and service needs changed, which resulted in the addition of a dock, breakwall and Roosevelt style boathouse in 1939. By 1991 the United States Coast Guard decided to move their station to Washington Island. For years, the structures on Plum and Pilot Islands remained boarded up and abandoned, until the lands were transferred to the U.S. Fish and Wildlife Service in 2007. Also, in 2007, the non-profit group Friends of Plum and Pilot Islands was formed to partner with the Service to preserve each island’s cultural resources including lighthouses, lighthouse keepers’ quarters, fog signal stations and the last Duluth-style lifesaving station on the Great Lakes. All of the historic structures on Plum and Pilot Islands are listed on the National Register of Historic Places.

Hog Island

Hog Island was set aside by Executive Order 1487 in 1912 as a preserve and breeding ground for native birds.

The chain of islands sprinkled between peninsulas are valuable patches of habitat for a variety of migratory species during both the migration and the breeding season. Hog, Pilot and Rocky Islands are valuable as colonial waterbird breeding, nesting and loafing sites. The location of these islands near forage fish habitat, combined with their remote and undisturbed condition, offer these species of migratory birds the necessary protected habitat. Habitat for colonial waterbirds has been under intense pressure on some Great Lakes islands as shoreline development continues.

Larger, forested islands also provide valuable feeding and resting stops for songbirds, bats and monarch butterflies migrating across open water. Habitat types differ from dense northern mesic forest, early successional forest and shrubby understory, to open habitat types of grassland, wetland and shoreline areas. Shoreline habitats on the islands range from sandy and silty areas to areas of exposed limestone bedrock, loose cobble-stone alkaline shoreline and globally rare alvar habitat containing specialized plants species.

In 1970, the United States Congress designated Hog, Gravel and Spider (Gravel Island National Wildlife Refuge) islands as the Wisconsin Islands Wilderness Area which, at 29 acres, is one of the smallest wilderness areas in the country. The prime management consideration of the wilderness status was the continued protection of nesting birds by limiting access to the islands during the breeding seasons. For this reason, the wilderness islands are closed to public visitation consistent with the conservation purpose of the refuge. The wilderness designation provides an additional level of protection on the islands and boaters are asked to stay at least a quarter mile offshore so as not to endanger the nesting areas.

St. Martin Island

St. Martin Island is closed to all public use.

Detroit Island

The Detroit Island Unit includes 148 acres open for public access including deer hunting.

Rocky Island

Rocky Island is closed to all public use to protect colonial nesting birds.

The refuge is managed by staff at the Horicon National Wildlife Refuge Complex in Mayville, WI.

Our Mission

The mission of the National Wildlife Refuge System is to administer a national network of lands and waters for the conservation, management and, where appropriate, restoration of the fish, wildlife and plant resources and their habitats within the United States for the benefit of present and future generations of Americans.

Green Bay National Wildlife Refuge was established on February 21, 1912 to serve as an undisturbed breeding ground for migratory birds and other wildlife. On October 17, 2007 Plum and Pilot Islands were added to the Green Bay National Wildlife Refuge to protect additional habitat for birds and endangered species within the Great Lake Basin ecosystem.

The Migratory Bird Hunting and Conservation Act uses money from Duck Stamp sales to purchase refuge lands. Many lands purchased with Duck Stamp funds were defined as inviolate sanctuaries. These lands, under most circumstances, must be at least partially closed to migratory bird hunting to allow birds a place of refuge and protection where they cannot be harmed.

Our History

1849 - The first lighthouse and keeper’s dwelling are built on Plum Island and known as the Port du Mort Light Station.

1858 - The light on Plum Island is determined to be too far west to aid shipping, so it is abandoned, and Pilot Island Light is built.

1890 - Due to increasing shipping traffic in the Port des Morts and prompted by a number of wrecks in the passage, the Lighthouse Board requests a $21,000 congressional appropriation to establish a pair of range lights on Plum island.

1895 - Congress appropriates the necessary funds on March 15th and the United States Life Saving Service hires Marinette contractor C.J. Olson to build a “Duluth style” lifesaving station on the north-eastern side of Plum Island.

1896 - Materials and workers are transported to the island in August and the range lights, steam siren fog signal, brick keeper’s dwelling and other structures are built. Work is completed and crew leaves on December 4, 1896.

1897 - The range lights are placed in operation on May 1, 1897.

February 21, 1912 - Green Bay National Wildlife Refuge was established with Hog Island by Executive Order 1487.

October 23, 1970 - Public Law 91-504, designated the Green Bay National Wildlife Refuge as a wilderness area wilderness area
Wilderness areas are places untamed by humans. The Wilderness Act of 1964 allows Congress to designate wilderness areas for protection to ensure that America's pristine wild lands will not disappear. Wilderness areas can be part of national wildlife refuges, national parks, national forests or public lands managed by the Bureau of Land Management.

Learn more about wilderness area

October 17, 2007 - Green Bay National Wildlife Refuge, Plum and Pilot Islands additions were established by Public Land Order 7681.

August 14, 2014 - Rocky Island was acquired pursuant of the Fish and Wildlife Act of 1956.

September 21, 2015 - The majority of St. Martin Island was acquired for administration by the Secretary of the Interior through the U.S. Fish and Wildlife Service under authority of the National Wildlife Refuge System Administration Act of 1966. The remainder of the island (57 acres) and the lighthouse are owned by the Little Traverse Bay Band of Odawa Indians.

March 28, 2019 - 148 acres were acquired on Detroit Island.

Other Facilities in this Complex