Yellow-headed Blackbirds Nesting and Leaving Hegewisch Marsh

Each year 10 to 17 yellow-headed blackbirds are born at Hegewisch Marsh, a natural oasis surrounded by an automobile factory, railroad tracks, and a garbage dump, just south of 130th and Torrence in Chicago (see "Post-Industrial Wildlands," CW Fall 2001). A recent $1.9 million Open Land Trust Grant awarded to the city for the acquisition of the ten-acre site will offer these endangered birds protection, as well as the least bitterns, pied-billed grebes, common moorhens, ruddy ducks, and willow flycatchers that also nest there.

Insect surveys have found numerous dragonflies and damselflies — the primary food of nestling yellow-heads — emerging from the wetland.

Mike Ward, a graduate student who has studied the site's yellow-headed blackbird population for five years, has found that while Hegewisch Marsh produces many young yellow-headed blackbirds, they don't return to the site once they leave. Nor do blackbirds born elsewhere choose to nest here.

"The reason appears to be because the habitat is so isolated," Ward explains. "Calumet used to be part of continuous range through northern Illinois and Iowa. Now it's corn and soybean fields and steel mills.... We're looking for new techniques to help the species locate the remaining high-quality habitat."

Without jeopardizing the site's nesting habitat, the city plans to build a nature center where neighborhood children will be able to learn about the Calumet area's original landscape and efforts to restore it. The Hegewisch Marsh acquisition is a part of the Calumet Open Space Reserve plan, a city and state partnership to develop a 4,000-acre natural area complex within the Calumet Industrial Corridor.

— Alison Carney Brown