The Calhoun Division of the Two Rivers National Wildlife Refuge along with the Mississippi River State Fish and Wildlife Area includes 14 wildlife management areas and 12 public access areas, scattered along 75 miles of two major rivers.

The area, located near Alton in southwestern Illinois, includes portions of both the Illinois and Mississippi Rivers. Within this refuge area, nearly 17,000 acres of wetland habitat are actively managed to provide restover sites for migratory waterfowl and shorebirds as well as habitat for breeding herons and egrets.

Ornithological Summary

Two Rivers functions as an important link in the chain of resting, feeding, and wintering areas for birds migrating along the Mississippi Flyway.

More than 200 different species of birds funnel through this important river juncture on their migration including more than 5,000,000 ducks such as Green-winged Teal, Northern Shoveler and Northern Pintail and 50,000 geese. Lesser Yellowlegs, Least Sandpipers, Pectoral Sandpipers and other migratory shorebirds arrive in hundreds to thousands to feed in shallow waters and mudflats. In addition, Great Egrets and Great Blue Herons use the area for nesting and feeding, along with fewer numbers of Little Blue Herons.

Open water pools, backwater sloughs, small impoundments, wetland management units, and a cooperative farming program attract these birds to the refuge.

Two Rivers also holds more than 600 wintering Bald Eagles, which arrive to the region in October and leave by March.

This site was chosen as an IBA as it met the criteria for breeding Prothonotary Warbler and also congregations of Waterfowl and Shorebirds


The Calhoun Division and the adjacent Mississippi River State Fish and Wildlife Area is just north of the confluence of the Mississippi and Illinois Rivers. This floodplain area includes Swan Lake as well as ponds, backwater sloughs, wetland management units, agricultural land and bottomland forest.

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