First acquired by IDNR in 1949, Mermet Lake is an old cypress swamp that has been converted into a lake and waterfowl hunting area. The over 2600 acre site contains a large, 452 acre lake that was formed from the construction of a series of levees. This lake is used for fishing and other recreational purposes and also acts as a reservoir to flood and provide habitat for the surrounding duck hunting areas.

Ornithological Summary

This site was chosen as an IBA because it met the criteria for winter congregations of Rusty Blackbirds.


Illinois Department of Natural Resources
South Region
1812 Grinnell Road
Belknap, IL 62908


A notable piece of habitat within Mermet Lake is the 385 acre Sielbeck Land and Water Reserve. This reserve contains over 110 acres of high quality floodplain forest and 35 acres of cypress / tupelo swamp. Some of the trees are over 200 years old and as much as four feet in diameter. The site was saved from logging and purchased by the Nature Conservancy in 1998 and since sold over to the IDNR.

Land Use

Mermet Lake has a loop road that goes around the length of the lake and is a popular location for fishing. During the fall, the areas below the lake are flooded and used for duck hunting. A couple small hiking trails and picnic areas are also present.

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