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Strength in Numbers

On the brink of extinction a few decades ago, sandhill cranes now descend by the thousands every year on a favorite spot in Indiana.



Every fall countless thousands of migrating sandhill cranes gather at the Jasper-Pulaski Fish and Wildlife Area in northwest Indiana. The crane has a coltish grace, standing four feet tall on spindly legs that at takeoff bounce in backbeat to the flap of the wings and before landing splay apart, slowing the 12-pound bird for a bouncy touchdown. Feeding in a marshy meadow, it struts with slow, angular precision, its plumage plain pale gray to brown except on the forehead, where the feathers fall out at maturity to reveal a patch of scarlet.

Sandhill cranes are exuberantly sociable. Their jaunty courtship jig helps males and females build a strong pair bond after they arrive at their breeding grounds. For most of the eastern population that's Wisconsin and Michigan, though small groups prefer Iowa, Indiana, and Ohio. The monogamous pairs raise one or two chicks each year, teaching them to forage through the summer and fall, communicating with a variety of bugling cries.

In late summer families begin to group into feeding flocks, which join with other flocks for the journey south. It's not uncommon for strings of 80 sandhills to pass over Chicago half a mile up, though they rarely stop here. They're drawn onward to Jasper-Pulaski, a patchwork of marsh, woods, and cornfields near Medaryville.

I drove down in early December. By then more than 20,000 sandhills had converged there. According to Doug Stotz, conservation biologist at the Field Museum, during migration nearly every crane from the eastern population passes through this small preserve.

I worried that I'd waited too long--the ground was already covered with a light blanket of snow. Jim Bergens, property manager at Jasper-Pulaski, had said the cranes usually leave when the weather turns.

Migrating sandhills follow the example of the hare, not the tortoise. Flying at 30 miles an hour, they make single-day journeys of 300 to 400 miles, then loaf for days or weeks at their staging grounds, building strength for another hard day's flight. Many flocks first gather near their nesting marshes in Wisconsin and Michigan 150 to 200 miles north of Chicago. Stotz says you can almost set your watch by them when they head south: they leave at dawn and reach the northern suburbs around noon, before arcing across the west and south suburbs toward Jasper-Pulaski. He says they leave the same way--a dawn departure followed by an all-day 350-mile flight to the Hiwassee Wildlife Refuge in Tennessee. "They're not making a milk run, with a lot of stops," he says. "They fly directly to the next staging area. It's rare to see one on the ground between here and there." Some of the birds will stay in Tennessee over the winter, but most press on to southern Georgia and Florida.

When I turned down the access road at Jasper-Pulaski early in the afternoon, 10 or 12 flocks, some 200 birds, were in the air. I trotted into a park outbuilding to put my name on the mandatory sign-in sheet. Many of the names above mine indicated they were visiting the "range," meaning the target-shooting area down the road. Jasper-Pulaski was established to provide habitat for game birds, not cranes, and hunting-license fees pay the bills and fund any new land acquisitions. All afternoon sharp gunshots in the distance underlined this point.

The sandhills spend their nights in hidden marshes at the center of the wildlife area. Every morning they assemble in a field called Goose Prairie, then most of them disperse in groups of 10 or 20 to surrounding cornfields, the source of the bulk of their fall diet.

Their migration is timed to the Indiana corn crop. Modern mechanized harvesters are cost-efficient, but they leave a lot of grain on the ground--a feast of leftovers for the cranes. "In September flocks feed wherever the fields have been harvested," says Bergens. "Later, as more fields become available, they try to stay close to the marsh, but some travel 15 miles away." In the late afternoon they fly back to Goose Prairie and remain there for an hour or so. After sunset they make the short trip across a line of trees to their roosting marshes, where they spend the night standing in shallow water.

I climbed the stairs of the viewing platform at Goose Prairie and found other crane watchers already up top. Snowy furrows, 500 yards across, stretched a mile to the west in front of us. I could see several hundred cranes strutting about the field, many of them quite close. It was a sign that a lot more birds were still in the neighborhood and would return as daylight faltered.

A little girl, four years old at most, peered through binoculars between the planks of the railing. Her grandfather, Jim Downs, a retired electrician and farmer from near Michigan City, said he'd brought her before. He also said he saw his first crane 50 years ago: "One crane was a special thing then. They wouldn't let you get anywhere near. I was outdoors all the time, but I hadn't ever seen one. You never thought you'd see 'em like this--this many birds together."

Fifty years ago the eastern population of sandhills had been nearly wiped out. For years hunters with "punt guns," heavy guns mounted in the bow of a punt, had descended on the immense Grand Kankakee Marsh, which once covered a large portion of northeastern Illinois and northwestern Indiana. They would bag hundreds of birds a day--ducks, geese, swans--and ship them to markets and restaurants in Chicago and New York. At the same time farmers were slowly ditching and draining the marsh, destroying the birds' habitat. By the 1950s only about 500 sandhills were left east of the Mississippi, including just 50 breeding pairs in the Wisconsin marshes. Stotz thinks it was around this time that most of those cranes began gathering at Jasper-Pulaski, a small remnant of the Grand Kankakee Marsh. "It may sound funny, but a tradition was set up," he says. "Cranes are long-lived birds, they travel in family groups, and the staging areas are ideal places to pass along learned behavior. This site had the conditions they were looking for, so as the population grew, they kept coming back."

The afternoon wore on, and more birds started to appear, making their bouncy landings on Goose Prairie. A red-tailed hawk soared across the field, but the cranes, with their seven-foot wingspans, didn't seem concerned. Bergens says the cranes have few enemies here. He's even seen them ignoring coyotes.

As the sun approached the horizon, the 30 or so people who'd gathered on the platform were spotting more and more incoming flocks. Someone saw 8 off to the southwest. Another 12 to the west. And 30 more in the south. The birds multiplied until cranes were flying all along the horizon, in chains of 30 or V formations of 50. A few small straggler groups separated from one flock and joined another.

As they approached the field the birds separated into threes and fours--family units, says Stotz. The foreground of the field began to fill in. In the distance there were so many birds I couldn't see the muddy snow anymore.

On one side of the field a contagion of gargled trumpeting erupted. In another section a dance spread from one bird to the next. They dipped their bills to the ground, raised their necks and pointed high, flapped their wings. Courtship, challenge, greeting?

There are words for groups of animals--gaggles of geese, prides of lions. The word for cranes is "siege." They'd certainly laid siege to this field--thousands upon thousands of them. Numberless birds. The sky was darkening, but flocks were still on the horizon, distant flecks strung out above the trees, homing in on the noise. As night fell it was hard to make out individual birds. The field was just a sea of gray rustling and raucous bugling.

Art accompanying story in printed newspaper (not available in this archive): photos/Carolyn Fields.

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