Forest Preserve District of Cook County, Illinois
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Wild Life Restoration in the Forest Preserves
Nature Bulletin No. 613   October 15, 1960
Forest Preserve District of Cook County 
Daniel Ryan, President
Roberts Mann, Conservation Editor
David H. Thompson, Senior Naturalist

The wealth of wildlife in the Cook County forest preserves rivals that in any of the other 101 Illinois counties, in spite of the fact that over half of the state's people are crowded within its boundaries.

The large variety of birds, mammals and other animal life now in this county is possible largely because the Forest Preserve District protects their natural habitats, including many that have been restored. These include timbered rolling uplands, wooded stream valleys, prairie remnants, sand flats, marshes, and a hundred bodies of water. Protection, for as much as forty years, against fire, hunting, trapping and other destruction has allowed the natural comeback of these habitats and the build-up of wildlife populations.

Our bodies of water and wetlands, some restored and some newly created. have been especially successful in bringing back the aquatic life which lived here before widespread drainage destroyed its habitats. Now wild geese, swans, and tens of thousands of wild ducks stop here to rest and feed during their spring and fall migrations. Herons, bitterns, ducks, coots, terns, kingfishers and many other water-loving birds are present from spring until fall. The woodcock, once rare, is often seen probing wet places for worms. The brilliantly colored wood duck, formerly scarce because of over-hunting and lack of nest cavities in trees, now breeds by the hundreds in the forest preserves.

Chicago began as a fur-trading post. Beaver were common and their valuable pelts were the principal article of trade. By 1803, when Fort Dearborn was built, they had been wiped out of this region and no beaver existed in Cook County until 1954 when two pairs were released in Saganashkee Slough, a 325-acre water area restored in the Sag valley west of Willow Springs Road. They promptly built lodges of saplings plastered with mud, and feed on the bark of cottonwoods and willows.

Although seldom seen in daytime, other fur-bearers are plentiful in the forest preserves. Almost every body of water has houses or bank dens of the muskrat. The tracks of several others -- mink, weasel, skunk, fox, raccoon and opossum -- are regularly seen in mud or snow. Although rare, the coyote and badger are reported every year or so.

The white-tailed deer disappeared from this region a century ago and were unknown here until about twenty years ago when a few were released in the Deer Grove and Palos preserves. These multiplied and others migrated here through adjacent counties. With fire protection and no more grazing of domestic livestock, wide areas have grown up in the shrubs and small trees on which deer browse and in which they find concealment. Now, a week seldom passes without one being seen in the preserves or crossing highways.

The wild turkey, largest upland game bird in America and ancestor of all our domestic turkeys, was once common in this part of Illinois. Due to excessive hunting and disappearance of large tracts of undisturbed woodland, they vanished over a hundred years ago. In our large Palos preserves there are now several square miles of virtual wilderness which provide favorable conditions for them to stage a comeback. Since 1954, four flocks of wild breeding stock totaling 73 birds have been released there. The wild turkey is shy and highly secretive in its habits but a few people have been fortunate enough to see young birds, with their parents, flying through the tree tops.

You should be proud of and help to protect your forest preserves.

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