IMPROVEMENT OF HABITAT QUALITY FOR NESTING AND MIGRATING BIRDS AT THEDES-PLAINES RIVER WETLANDS DEMONSTRATION PROJECT

The Des Plaines River Wetlands Demonstration Project includes a series of man-made marshes constructed on degraded habitat (abandoned agricu ltural land, gravel quarrying pits, etc.) within the floodplain of the Des Plaines River in northeastern Illinois, USA. Avian use of the sit e was measured before wetland construction in 1985 and after construct ion from spring 1990 to summer 1991. Pre-construction censusing indica ted that no endangered or threatened species nested within the project site, and that use of the site by migratory waterfowl was minimal. Po st-construction censuses revealed that wetland construction resulted i n the arrival of two state endangered species, Least Bittern and Yello w-headed Blackbird, which nested on site, and in three state endangere d species, Pied-billed Grebe, Great Egret, and Black-crowned Night-Her on, which visited the site during the breeding season. Similarly, post -construction censusing indicated that the number of individuals and s pecies of waterfowl using the site increased about 4000% and 400%, res pectively. These results demonstrate that the Des Plaines River Wetlan ds Demonstration Project has improved habitat quality for nesting and migrating birds.