Biologist Brad Semel likens the bugling duet of sandhill cranes to the unexpected howling of a pack of wolves.
Semel treasures such sounds because they recall pre-settlement times, when there were more wild places than subdivisions in the nation.
Today, the subdivisions have the edge. As undeveloped lands shrink, graceful creatures such as Illinois’ sandhill crane have been forced onto the state’s endangered species list.
Once thought to be exterminated in the state, about 40 of these magnificent birds are estimated to live in northeastern Illinois’ few remaining wetlands, according to a recently completed census of cranes in Lake, McHenry, Kane and portions of Cook Counties. The census was done by biologists at the Illinois Department of Conservation and by volunteers for the International Crane Foundation, based in Baraboo, Wis.
For more than a century, from 1872 to 1979, not a single sandhill crane was found to be making its home in Illinois, although biologists say the cranes seem to be doing well in Wisconsin, Minnesota and Michigan. But 50 years ago, fewer than 50 nesting pairs were known to be in the Midwest, said Rob Nelson, of the crane foundation.
Their numbers were threatened by hunters and by loss of wetlands that were the cranes’ habitat. Up to 85 percent of Illinois’ original wetlands are estimated to be lost.
The annual crane census was begun in 1983 by conservationists to keep track of the birds after a nesting pair was spotted in northern Lake County in 1979.
In the past decade, the numbers of nesting cranes counted during the census has been rising, and biologists cautiously hope that the Midwest’s largest wetland bird once again may be setting up housekeeping in Illinois.
“The single most impressive thing is being in wetlands . . . and listening to their calls,” said Semel, of the Department of Conservation. He coordinated this year’s crane census for the state.
A crucial component of the census is defining the wetlands that attract the birds, especially in fast-growing Lake and McHenry Counties. Typically, the birds spend their winter in southern gulf states, but migrate to northern marshes for the summer nesting season.
The birds need expansive marshes to survive-not postage stamp-size wetlands that may be wedged into the faux natural areas that sometimes accompany the landscaping at a subdivision. Thus, they can be seen in places like Chain o’ Lakes State Park or Volo Bog, which have vast protected areas.
“Wetlands loss in this area has been tremendous with human and agriculture development,” Semel said, “so we are trying to monitor and identify sites that are critical for nesting. It’s no coincidence that they are returning to nest in larger preserves that are protected.”
With a wingspan of 6 to 7 feet and a body weight of 8 to 11 pounds, these massive waterfowl might seem easy to spot, but the grayish birds with a reddish crest are neatly camouflaged among the mud and reeds.
In flight, they often are mistaken for the great blue heron. Unlike the heron, which flies with a crook in its neck, the sandhill crane flies with neck outstretched and legs trailing behind.
“When you see a crane next to or near a heron, the crane looks like a cow, it’s so big,” said Randy Heidorn, an ecologist with the Illinois Natural History Survey.
Meanwhile, experts caution that it is too early to celebrate the cranes’ apparent return to Illinois.
The cranes may be finding wetlands suitable for nesting, but there may not be anything for them to eat in the nearby suburban lawn.
Their diet includes insects, snakes, grain, frogs and mice found in the dry upland areas that abut a wetland. But, Semel noted, such land often is developed, which effectively eliminates the sources of food.
Conservationists will continue to monitor the cranes in the hopes that habitat can be protected and their return to Illinois ensured.
“If they disappear,” Semel said, “I could never show my children what magnificent animals lived here.”
