In the 1980s and 1990s efforts to create a new migratory population between Montana and New Mexico by introducing whooping cranes into migrating sandhill crane groups ran into trouble when whooping cranes tried to mate with the sandhills.
"We had no way of reestablishing a migratory population until Operation Migration came along," said Tom Stehn, coordinator of the U.S. Fish and Wildlife Service Whooping Crane Recovery Team. "It's really a breakthrough."
If more than 125 birds can learn the route and start migrating on their own, the population could be self-sustaining, he says. The Operation Migration team started with 7 birds in 2001 and has now taught more than 60 birds the way to their wintering grounds.
Baby Steps
Getting these cranes ready for flight starts long before they're even born.
Chicks begin to recognize their parents' voices while still in the egg, says John French, research manager at the U.S. Geological Survey's Patuxent Wildlife Research Center in Maryland.
At the research center, French's team begins playing recordings of sounds from the birds' natural habitat—including the calls of adult cranes—before the chicks crack their way through the shell.
Once the cranes hatch, the people who train and care for the chicks wear full costumes that hide the researchers' faces under a helmet and visor, their feet in black rubber boots, and their hands in puppets that bear an adult crane's markings. (See a video of the costumed scientists.)
"Any bird worth its salt would recognize that it's not a bird," French said.
But the goal, he says, is to prevent the cranes from recognizing and becoming comfortable with humans, so that when they migrate on their own, they won't show up in parking lots and soccer fields looking for food.
During their first six to eight weeks at Patuxent, cranes learn how to feed and exercise and are introduced to an ultralight like those they'll follow along the migratory route.
Then they fly—as passengers on a special plane—to Necedah National Wildlife Refuge in Wisconsin to begin their flight training.
Cranes, Planes, and Automobiles
Whooping cranes aren't the first birds to follow ultralights.
In the early 1990s Operation Migration's co-founders, Bill Lishman and Joe Duff, led a flock of Canada geese from Ontario to Virginia. The birds returned to Ontario without a guide the following spring.
In 2000 the Whooping Crane Eastern Partnership worked together to test the first full migration with sandhill cranes. A year later Operation Migration's pilots flew with whooping cranes along the same route.
This year's flock consists of 18 cranes and four ultralights. A Cessna circles 1,000 feet (305 meters) above the group, staying in contact with local air traffic control.
Along the ground a caravan of ground crew and volunteers zips along to meet the group at the next rest stop. Weather permitting, the ultralights take off at dawn and fly as far as 200 miles (322 kilometers) each day.
These intense efforts are starting to pay off for whooping cranes. "We are just really enthused that this is working," Stehn said.
And today's start—the earliest yet for the migration—might give this flock a jump on winter weather later in their migration, which may take two months or more.
Condie said everyone is "happy that it went as well as it did, and happy that we started a little earlier this year."
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