Green Bay National Wildlife Refuge is made up of several islands located located in Lake Michigan, between Wisconsin’s Door County Peninsula and Michigan’s Garden Peninsula. The refuge is made up of Plum Island, Hog Island, Pilot Island, St. Martin Island, Rocky Island and a parcel of land on Detroit Island. Part of the refuge is open to public access and the rest is closed to protect colonial nesting birds and other species.

Visit Us

National wildlife refuges offer us all a chance to unplug from the stresses of daily life and reconnect with our natural surroundings. Green Bay National Wildlife Refuge contains ecotypes and habitat rare elsewhere in Wisconsin, including the coastal fens and alvars. These communities support rare plants such as dwarf lake iris and Canada yew. With Lake Michigan as the backdrop, there are many opportunities to explore these rare communities, see unique wildlife species and take in views of historic lighthouses and shipwrecks.

Location and Contact Information

      About Us

      Green Bay National Wildlife Refuge is made up of several islands located 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

      Part of the refuge is open to public access and the rest is closed to protect colonial nesting birds and other species. The refuge is managed by staff at the Horicon National Wildlife Refuge Complex in Mayville, WI.

      Our Species

      Hog Island provides nesting habitat for colonies of herring gulls, great blue herons, black-crowned night herons and great egrets. Pilot Island provides nesting habitat for herring gulls and a large colony of nesting double-crested cormorants. Plum and St. Martin Islands contain ecotypes and habitat rare elsewhere in Wisconsin, including the coastal fens and alvars. These communities support rare plants such as dwarf lake iris and Canada yew, making the refuge a unique opportunity for conservation and management.