Michigan Islands National Wildlife Refuge is closed to the public. Five of the islands are small, 11 acres or less, while the remaining four are around 220 acres in size. The smaller islands have little vegetation and a casual observer can see colonial nesting birds during the breeding season. The larger islands have a number of trees making it difficult to watch for birds using the interior of the island. Because the islands are closed to the public, the only wildlife observation or photography allowed is from a boat. Caspian terns, common terns, ring-billed gulls, herring gulls, double crested cormorants and several other species of birds nest on these islands. Caspian and common terns are considered threatened species in the state of Michigan. Because of the sensitive nature of nesting birds, please remain a respectful distance from the islands and view wildlife with binoculars. Approaching an island too closely may disturb birds, exposing eggs and young to predators and the elements, or cause the birds to abandon their nests altogether.