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The Flickr site is brought to you courtesy of Seney Natural History Association.
Common Tern. Credit: Kirk Rogers, USFWS.
Caspian Tern. Credit: Jerry Kirkhart, Flickr Creative Commons.
Black-crowned Night Heron. Credit: Lee Karney, USFWS.
Herring Gull. Credit: John Haslam, Flickr Creative Commons.
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Four of the eight islands that make up Michigan Islands National Wildlife Refuge (NWR) fall under the management of Seney NWR. These islands, Gull, Pismire, Hat and Shoe, are part of the Beaver Archipelago in Lake Michigan. The other four, Thunder Bay, Scarecrow, Big Charity and Little Charity Islands, are located in Lake Huron and managed by Shiawassee NWR. For questions regarding these islands please contact Shiawassee NWR.
Michigan Islands NWR was established as a refuge and breeding ground for migratory birds and other wildlife. Shoe Island (one acre) and Pismire Island (two acres) were among the first to be acquired in 1947 and were designated as Federal Wilderness Areas in 1970. At 230 acres, Gull Island, located west of Beaver Island, is the largest of the four islands managed by Seney NWR. The U.S. Coast Guard ceded the island, which once housed a lighthouse keeper, to the service in 1969. Hat Island, at 11 acres, is the most recent addition to the Refuge, acquired from The Nature Conservancy in 1994. In 1943, during World War II, Hat Island was bombed for target practice by the U.S. Navy. At that time, Hat Island was burned and partially covered in tar reducing its vegetation, but once left to natural processes trees and other vegetation eventually returned.
Habitats vary considerably between islands. Shoe Island is little more than a cobblestone islet with small patches of grass and herbs. Pismire Island sits a little higher than Shoe and is covered in shrubs and scattered vegetation.
Hat Island has had a significant alteration to its forest vegetation due to nesting waterbirds, especially double-crested cormorants, which could be viewed as a natural ecological disturbance. When the population of cormorants is high, vegetation is reduced. When the population decreases the island’s woody vegetation will likely return, as it did after the bombing in 1943. In the meantime, the bird species using the island will change as the vegetation changes. When trees are available, herons may nest. As vegetation is reduced, birds like caspian terns and gulls, which are ground nesters, make use of the opportunity. Double-crested cormorants can adapt to either situation by nesting in trees or on the ground as the opportunity presents itself. Cormorants were first recorded nesting on the island in 1984 and have been using the island continuously to the present date.
Gull Island has the most diverse plant community with a grass and wildflower covered beach area above the high water line, a shrub-covered sand dunes area, and a variety of trees in the interior of the island including: paper birch, red maple, sugar maple, northern white cedar, balsam fir, white spruce, and trembling aspen. Canada yew dominates the groundcover.
The islands are a result of glacial forces from the last Ice Age. At glacial Lake Algonquin’s lowest water stage, approximately 200 feet below present lake levels, all the islands of the Beaver Island chain were connected to the mainland via a land bridge. The islands are similar, varying in size and elevation. They portray an ecological sequence from Shoe Island, which has the lowest elevation, to Gull Island, which has the highest elevation. The topography of the islands is basically flat with elevations ranging to 10-15 feet above the average lake level. Soils consist of shallow organics or sands over cherty limestone and dolomite.
Wildlife observations include 69 species of birds and two species of mammals, deer mouse and snowshoe hare. Gull and Hat Islands host the greatest numbers and diversity of species. Over the past ten years, these islands have supported both ring-billed and herring gulls, great blue herons, black–crowned night herons, double-crested cormorants and caspian and common terns. Other bird species found breeding on these islands, include spotted sandpipers, killdeer, waterfowl and a variety of raptors and songbirds.
Michigan Islands NWR has exceptional value to colonial nesting waterbird conservation in the Upper Great Lakes region and specific islands have been proposed as Important Bird Areas by The Audubon Society for species such as black-crowned night heron (Gull Island) and caspian tern (Hat Island). Caspian terns are currently listed as threatened in Michigan.
Allowable Activities:
- Shoe and Pismire Islands of the Michigan Islands NWR are designated Federal Wilderness Areas (PDF file size 1.7 MB).
- All islands of the Michigan Islands NWR are closed to the public due to their value to colonial nesting waterbirds. Special Use Permits may be issued for approved purposes. Exceptions are emergency landings by boats in distress.
- Wildlife observation and photography are welcome off-shore.
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Hat Island of Michigan Islands NWR. Credit: Mark Vaniman, USFWS.
Pismire Island of Michigan Islands NWR. Credit: Mark Vaniman, USFWS.
Gull Island. Credit: Mark Vaniman, USFWS.
Great Blue Herons. Credit: Julie Christiansen, 2010 Photo Contest.
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