By Candice Ludlow
http://stream.publicbroadcasting.net/production/mp3/wkno/local-wkno-875263.mp3
Memphis, TN – Whooping cranes are on the brink of extinction. In 1937, according to the U.S. Geological Survey, there were fewer than 20 whooping cranes left in North America. By 1941, biologists started trying to breed them in captivity. Now, Operation Migration is teaching 20 whooping cranes their migration route. Candice Ludlow drove down a two-lane road before dawn near Huntingdon, Tennessee to watch the five-foot, white birds take flight.
To keep the ancient birds wild, their exact location is only known by a few: the ultra light aircraft pilots and biologists teaching them their migration path. Operation Migration's Winnebago was parked along the slightly windy road just before daylight on Wednesday. Two cars and a truck pulled up, too. It was 22 degrees. An ultra light aircraft flies up near the Carroll County Airport.
Liz Condie is bundled up. She sees the ultra light and reaches into the Winnebago for the radio .
My concern is getting em to a thousand feet. I'm at 500 and it's trashy still.
Joe Duff is the co-founder of Operation Migration. He's also one of four guides, or ultra light aircraft pilots, who are teaching the young whooping cranes their migratory path from Wisconsin to Florida.
"And when we say it's trashy, today we have a pretty strong wind blowing in the right direction, but it's rolling over the hills and over the trees and creating some thermals, and some mechanical turbulence down below," Duff said.
The birds have been grounded for five days in Carroll County, waiting for the right conditions.
"In the wild, whooping cranes are soaring birds. They would take off and fly like a hawk or an eagle. And they hardly expend any energy. They just circle around and they'll find rising columns of air. As the sun heats the Earth it doesn't do it evenly. And some air areas get warmer than others. And that air rises. That's called a thermal. So they would circle on that thermal and just get an elevator ride up. They wouldn't be flapping their wings. They would just go up. When that tops out at five - 10-thousand feet, who knows, they would glide to the next one in the direction they want to go, find another one, up they go again. And that's how they migrate," Duff said.
But the ultra lights can't mimic their flight patterns.
"We can't stay airborne long enough and our aircraft don't glide as well as that, so our birds learn to fly on the wake created by the aircraft. As we plow through the air, it creates a wake behind the wing on the wingtip. It's called a vortices, and the birds can fly on that. So they form on our aircraft in the same V-formation they fly in the air," Duff said.
Liz Condie, the woman with the radio, says the whooping cranes are conditioned to imprint on the ultra light before hatching. They play recordings of ultra lights while they're still inside the eggs. When the birds reach 40 days, they import them to their new home - Necedah National Wildlife Refuge in Wisconsin. Before they ever fly.
"We continue throughout the summer, doing what we call first taxi training, and that's just a wingless trike running up a grassy strip. And the birds running along behind and following it. And eventually, once they have their flight feathers, we leading them on circuits above the refuge to build up their stamina and loyalty to the aircraft," Condie said.
This is the ninth flock to migrate. Once the whooping cranes reach their winter home in Florida, they are what Joe Duff says, "gently released" into the wild They're housed in huge pens that are not netted.
"And so after a couple of days, the birds realize that they can fly out. And they do. They fly out during the day and probe in the marsh and eat blue crab and learn to be wild birds. And then at night, the handlers show up, and of course they have food, and the birds come back in. And then they roost in the water, they sleep standing in water inside the pen, and they're protected from predators that way," Duff said.
The birds are equipped with tracking devices, which Joe Duff says, is monitored by the International Crane Foundation and US Fish and Wildlife Service. Since 2001, they've led 100 birds south. Some have been lost, but most have returned to Wisconsin or migrated somewhere nearby.
The crew is anxious to take the whooping cranes to their next destination, somewhere in Hardin County, TN - near Savannah.
"The winds are significantly lighter up top. We do have 20-30 miles an hour this morning. And it looks like they're dropping down to about 5," Condie said.
Check out Operation Migration's website to keep up with the whooping cranes' flight path, field reports and to see the magnificent birds.
http://www.operationmigration.org