The St. Joseph Island Migratory Bird Sanctuary, maintained by the Canadian Wildlife Service, provides 940 hectares at the south-western tip of the island as a habitat for waterfowl and other wetland-dependant migratory birds during critical periods of their life cycle. The sanctuary, established in 1951 to protect migratory birds from extensive hunting, includes a large marsh along the St. Marys River shoreline, a few small lakes and swamps as well as several islands. Among the species of birds that frequent the sanctuary are American black duck, common merganser, red-breasted merganser, lesser scaup, greater scaup, black tern, herring gull and bald eagle.