More than 200 people spent last Saturday in meeting rooms at Northeastern Illinois University learning about birds and habitat management in the Chicago wilderness region. On hand were scientists and land managers from various institutions, birders with experience at monitoring changes in bird populations, and birders with no such experience.
Meetings like this are becoming commonplace in this part of the world, though they are rare elsewhere. A close collaboration between people with graduate degrees in various aspects of biology and people who have learned the biology they know through field experience is part of the culture of the Chicago area. It is one of the social forces that led to the creation of the organization called Chicago Wilderness. That organization is in turn stimulating more such collaborations by providing an institutional base and some financial support.
Chicago Wilderness is a coalition of, so far, 54 organizations from northeastern Illinois, northwestern Indiana, and southeastern Wisconsin. It includes government agencies on the federal, state, county, and local level; educational institutions; and environmental advocacy organizations such as Openlands Project and the Sierra Club. The organization's purpose is to protect what remains of nature in this heavily populated region. The basis of that effort is the seeming paradox that there is more nature to protect in the third-largest metropolis in the country than there is in the sparsely populated farmlands surrounding it. The ecosystems unique to the midwest might not survive at all if they don't survive here.
The sponsors of last Saturday's conference were a group of ten birders' organizations--including the Chicago Audubon Society, the DuPage Birding Club, and the Thorn Creek Audubon Society--that have joined to form a coalition called the Bird Conservation Network. This umbrella organization expects to join the Chicago Wilderness coalition.
The complaint of people interested in birds has been that land managers look only at plants when they formulate plans for restoration and management of natural lands. There are grounds for that complaint. A land manager examining a site with an eye to developing a management plan looks at the whole biota, but some parts of the biota carry more information about the history of the site than others. There are many prairie plants that are found only on prairies and many oak-hickory woodland plants that are found only in oak woodlands. When land managers find a noticeable number of exclusively oak-hickory woodland species, they are likely to conclude that the site should be managed as a woodland. Animals add more information. The presence of smooth green snakes says this was once prairie. Tiger salamanders tell us that an oak savanna was once here.
Birds tell us almost nothing about the history of a place. Birds are very mobile. They abandon unsuitable places and colonize suitable places with great rapidity. They tell us much about what is happening in our environment right now, but nothing about what came before, so they are often ignored in land-management decisions.
However, their ability to react quickly to changes in the environment makes them very useful indicators of environmental change, and that means we need to keep track of what is happening to them. One of the hoped for outcomes of last Saturday's conference is an increased monitoring effort to be carried out by the many skilled birders in the Chicago area.
The conference began with a welcoming speech by Dan Williams, a former president of the American Birding Association and an adviser to the Winnebago County (Rockford) Forest Preserve District. Williams described the conference as the beginning of a partnership of land managers and birders, an opportunity to make "one coherent" effort to protect our natural lands and all the species that live on them.
He was followed by four scientists who in recent years have made major contributions to the knowledge of birds in our region. Jeff Brawn of the Illinois Natural History Survey talked first about the birds of savannas. Brawn has been studying birds in savannas and oak woodlands along the Illinois River south of Peoria and in the Palos preserves in Cook County.
He talked to us about disturbance-dependent species. Our savannas and oak woodlands require periodic fire--disturbance--to sustain them. The birds of these communities are equally fire dependent, but the connection is indirect. These birds nest in open woodlands, where there is some space between the trees. In our part of the world that open quality can be maintained only by fire. Without fire, the woods become too dense for these birds.
Brawn has identified 54 species of savanna birds in Illinois. Almost 70 percent of them are suffering population declines. They are losing ground faster than forest birds. Among the species of the savannas are such colorful birds as the red-headed woodpecker, a bird that contributes to the life of savannas by caching acorns that may later grow into mighty oaks. The Baltimore oriole is another savanna species, as is the barn owl, a species on the endangered list in Illinois.
Brawn's studies have shown that introducing fire into savannas and oak woodlands does increase the reproductive success of such savanna species as the rose-breasted grosbeak and the indigo bunting. His studies in the Palos area showed that cowbird parasitism is not as heavy as it is downstate. Cowbirds feed in plowed fields and pastures. They commute to woodlands and forests, where they lay their eggs in the nests of other birds. There is not much farmland left near the Palos preserves, and that may account for the lower parasitism rates. In the Palos preserves only 30 percent of indigo bunting nests contained cowbird eggs. For wood thrushes and veeries, the figure was 64 percent. This sounds like a lot, but compared to downstate, where the infestation approaches 100 percent, it is low.
Scott Robinson was one of the first scientists to call attention to the large problem of cowbird parasitism among forest birds. These birds have no evolutionary history of parasitism, because cowbirds generally did not invade forests in the past. With no history of coping with this threat, the forest birds have taken a severe hit. Robinson, who is also with the Illinois Natural History Survey, followed Brawn on the program. He pointed out the importance of preserving large sites to protect forest birds. He also called attention to the importance of the Chicago region as a migratory stopover for birds flying to and from the large forests that remain to the north of us.
James Herkert of the Illinois Endangered Species Board spoke about grassland birds. Two hundred years ago the birds we call grassland birds were prairie birds, because that was the only kind of grassland there was. They have since learned to occupy meadows full of Eurasian grasses. Herkert's studies over the past decade have called attention to the need to preserve large blocks of grassland to protect these birds. There is virtually no chance of attracting a native prairie bird to a site smaller than about 25 acres, and the larger the site the better your chance of seeing nesting bobolinks and grasshopper sparrows. Herkert has found that even very small amounts of encroachment by woody plants--trees and shrubs--causes grassland birds to abandon a site.
Herkert's research has enabled him to make very specific recommendations for land management for grassland birds. We can now make decisions about the size of preserves, the scheduling of mowing and burning, and the treatment of invading shrubs and trees with a reasonable level of confidence about the effects our decisions will have on grassland birds.
Charles Paine of the Max McGraw Wildlife Foundation closed the morning with a discussion of his research on wetland birds in the Chicago region. He studied birds on 11 sites in Lake and Kane counties. His results underlined the importance of preserving a variety of wetlands, of preserving wetland complexes, and of concerning ourselves with the land surrounding wetlands. Wetlands surrounded by development have more flooding and more raccoons--important nest predators--and have less food available than wetlands surrounded by undeveloped land.
Lunch was a working session devoted to a discussion of monitoring methods. The favored methods of ornithologists are usually not the sort of thing that birders enjoy. Given a free choice, most people would avoid standing in one place for a long time in a mosquito-infested woodland. On the good side, our working lunch attracted an overflow crowd, an indication that many people are interested in making a contribution.
After lunch we split up into concurrent sessions on major restoration projects in the region. Wetlands, riparian areas, woodlands, prairies, and savannas were all discussed.
At the end of the afternoon we gathered again to listen as Douglas Stotz of the Field Museum placed our local avifauna in a global perspective. Chicago is in a trough between peaks in many respects. We are too far south for the birds of the northern forests and too far north for the rich bird life of the southern states. However, we can make a significant contribution to the preservation of wetland birds and grassland birds. And we can especially help migrant species make their semiannual journeys. After miles and miles of plowed fields an exhausted songbird can set down in the parks and preserves of the Chicago area and rest and refuel for the remainder of its flight.
For those of us with an interest in nature and a desire to help preserve what remains of the nonhuman parts of the natural world, Chicago is a very interesting place to be right now. An extraordinary combination of scientists and lay people and government and private groups is creating a real reason to be hopeful.