Apostle Islands National Lakeshore - Birds

Apostle Islands National Seashore by National Parks Service

The Apostle Islands National Lakeshore, with its strategic geographic location and wide diversity of habitats, provides a refuge for birds. The Apostle's were identified in the 1950's and 1960's as one of the heaviest traveled migratory flyways in the Great Lake Region. This is due to the presence of the islands reducing the distance birds have to fly over open water when migrating to areas north of Lake Superior. Outer and Long Island provide critical habitats for migratory birds: Outer for passerines, hawks and falcons, Long for waterfowl, passerines and shorebirds. In addition to these two islands, nearly all of the islands provide habitat for migrating birds.

Since 1990, migratory bird surveys have been conducted on Outer and Long Islands and are part of a long-term monitoring program. There are large fluctuations in migratory volume from year to year, especially on Outer Island, most likely due to highly variable weather conditions. The islands also provide important habitats for resident breeding birds as well as neotropical migrant land birds (those, which migrate to Central and South America in winter). Over 89% of the breeding birds in the Lakeshore are migrants, 59% of which are neotropical migrants. The Lakeshore established an annual breeding bird survey in 1990 in response to the growing need to document abundance trends of neotropical migrant birds in the United Sates. The Lakeshore provides important nesting habitat for the following colonial nesting birds: herring and ring-billed gulls, double-crested cormorants, great blue herons, and cliff swallows. Gull and Eagle Islands combined have 88% of the lakeshore's breeding herring gull populations and 80% of the herring gull breeding population on the entire Wisconsin shore of Lake Superior. Eagle Island has the only great blue heron rookery in the park. The Lakeshore also provides nesting habitat for bald eagles (Federally threatened) and shorebirds such as the Federally and State endangered piping plover.