The immature reddish egret lingers at Lake Calumet. It is a sign that summer is still with us. But walking my dog in Horner Park this morning, I heard in the soft hissing call notes of migrating warblers the first whispers of fall.

The natural world is slipping from summer into autumn, and the birds, in their usual conspicuous fashion, are producing the clearest marks of change. The reddish egret is a phenomenon of late summer. Many members of the heron family wander in August and early September after the nesting rookeries break up for the year. Late summer is the likeliest time of year to see a heron outside its normal range.

However, this reddish egret is way outside its range. The nearest nesting location for the species is coastal Louisiana and Texas. The bird that has been hanging around Lake Calumet is the first reliable sighting of the species ever in Illinois.

It seems fitting that this first sighting should be at Lake Calumet. Presumably the bird passed over lots of marshes on its way north before settling in at 122nd and Stony Island. The battered remnants of our once-glorious Chicago marshes are despised by many people, but the birds continue to testify to their excellence.

I first visited the Calumet marshes in the summer of 1981. Larry and Barbara Balch were my guides. I was working on a story about birding for Outside magazine. At the time Larry was running the Chicago Audubon Society’s rare-bird hotline. He has since served a couple of terms as president of the American Birding Association.

I was blown away by what Larry and Barbara showed me that day. In the middle of all those steel mills, paint factories, and garbage dumps were these incredible wetlands where migrating dowitchers fed on mud flats. Black terns hawked for insects over the open water between the beds of reeds and cattails. Yellow-headed blackbirds sang their clanking songs, and black-crowned night herons seemed so common you could look up at any time and see at least one passing over.

One of the places we visited was the largest of the remaining wetlands. Birders call it the Big Marsh. It lies north of 116th Street between Stony Island and Torrence. In 1981 it was owned by Interlake Steel, but not long after my first eye-opening visit Waste Management bought it and announced plans to convert it into a landfill.

That announcement precipitated a whole series of interesting events that may in time lead to the preservation of the remaining Calumet marshes. Jim Landing, a geography professor at UIC and a very active birder, started a group called the Lake Calumet Study Committee, an umbrella group whose members were mostly birding organizations. Jim does have a facility for pissing people off. He has had major arguments with practically everybody–including me–but he was the first person to step forward to try to save the marshes. He was also the first person to put together a coalition between neighborhood people from the southeast side and environmentalists. And he has stayed at it. He is still working to preserve the marshes more than a decade after forming the committee.

Conservatives like to characterize the environment as an elite issue. Limousine liberals destroying the economy so they can keep their favorite beaches to themselves or have the pleasure of looking at pretty little dickeys. But the heaviest costs of environmental destruction, the costs in health and money, fall mostly on the working class. The former steelworkers and refinery workers and chemical workers of the southeast side of Chicago and across the line in northwest Indiana are looking for work in a devastated landscape that has little appeal for new businesses. And it is their children who are growing up in an environment where breathing is a high-risk activity.

The battle over the Big Marsh landfill opened up lines of communication between neighborhood people and the mainstream environmental groups, and those lines have stayed open. When Daley decided to bury the southeast side under runways, an effective opposition was already in place. We had shot down other crackpot schemes; we could shoot down this one.

It has been years since I took any active part in the Lake Calumet struggles, but people now involved–including people not given to flights of thoughtless optimism–are cautiously hopeful. We haven’t lost an acre of wetland since the Lake Calumet Study Committee was formed. The ecological value of the marshes has been established beyond dispute. I remember going to a meeting of the executive committee of the Chicago group of the Sierra Club some ten years back and making a pitch for getting the club involved in fighting for the marshes. I’m still not sure if anybody there believed I was serious. Certainly nobody was anxious to get the club into a battle to preserve natural areas whose nearest neighbors were coke ovens. (In fairness I should add that the Sierra Club has since gotten very active in the fight to save the marshes.)

Today, I am told, even bureaucrats employed by the city of Chicago are making cautious noises about the need to preserve what is left of the marshes. Nature has become a bit of a drawing card. If you could promise that the CEO’s office would have a view of a heron rookery, you might get a company to move to Lake Calumet.

The reddish egret’s stay at the marshes has extended over several weeks. The reddish egret nests in Baja California and around the Gulf of Mexico and Caribbean as far south as Guatemala. In the U.S. it nests only in southern Florida and along the coasts of Louisiana and Texas. Plume hunters wiped out the Florida population in the early years of this century, but the species has since managed to reestablish itself there.

It is a colonial nester, building stick nests in mangrove thickets or similarly brushy situations. It has a typical heron look about it: long bayonet bill, long legs, long toes for walking on mud without sinking in. It is medium size, for a heron, with a wingspan of just under four feet.

Its food is also typical heron fare: small fish, crayfish, crabs, frogs. Reddish egrets do have an extraordinary hunting method. Standing in shallow water, they spread their wings and lurch about–“drunkenly” is the way all the books describe it. Apparently their staggering causes various potential food items to flee places of shelter on the bottom. The spread wings may be part of the strategy. The disturbed animals would tend to flee the light, heading toward places of sheltering darkness. The urge to escape the light might put them right under the heron’s daggerlike beak.

It’s nice that birders from all over Illinois have to come to Chicago to see a reddish egret. Only here have we had enough wisdom and foresight to preserve marshes as fine as those at Lake Calumet.

Meanwhile the autumn advances. During the next few days check the sky from time to time for passing nighthawks. They are easily recognized. They are slightly smaller than pigeons with long, narrow, pointed wings. A broad, white transverse stripe is plainly visible between the bend of each wing and the tip.

Nighthawks are normally nocturnal birds, but they migrate by day. This is a reversal of the pattern of our diurnal songbirds, which usually migrate by night. Their flight is light and buoyant, and they often ride winds and thermals without moving their wings at all.

Chicago is also full of thrushes right now. I must have seen 20 birds on my block in the past few days. We have five species of thrushes passing through Chicago during migration. Most of the birds around now are either gray-cheeked or Swainson’s thrushes. Both species have unmarked gray brown backs and lightly speckled underparts. They are noticeably smaller than robins but larger than sparrows. If you get close enough, you can tell the two species apart by looking at their eyes and cheeks. Swainson’s thrushes have prominent buffy eye rings and more buff color on the lower part of the cheek.

Thrushes are all ground feeders –like their cousin the robin–so you might want to keep your cats indoors for a while.