The world's largest freshwater delta; composed of approximately 25,000 acres of cattail, bulrush, and grasses interspersed with open channels.

Ornithological Summary

A highly important wetland for breeding, migrating and wintering waterfowl and very high densities of rare marsh-nesting species including American and Least Bitterns, Forster's and Black Terns, and Marsh Wren. This site is probably the state's most regular breeding site for the state endangered King Rail. Recent breeding season estimates include 80 Virginia Rails, 54 Soras, 70 Common Moorhens, 52 pairs of Forster's Terns, 650 Black Terns, 46 Least Bitterns, 79 American Bitterns, 57 Purple Martins, and 2 Northern Harriers. Migrant waterfowl use this site and the adjacent Lake St. Clair in very high concentrations; most notably, the Canvasback and Tundra Swan.

Conservation Issues

Invasive species present a huge threat to the habitat quality, especially Phragmites and Purple Loosestrife. Recreational boat traffic can provide a large amount of disturbance to birds.


St. Clair Flats Wildlife Area (Michigan Department of Natural Resources)


Dominated by cattail and bulrush emergent marsh, with pockets of upland shrub and forest.

Land Use

Wildlife conservation and recreational boating and fishing are dominant uses.

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