The setbacks that dogged the flight in October largely removed, the flock of whooping cranes making its way to Florida has passed the halfway point and could soar into Georgia this morning.
If all goes well, they would arrive at Chassahowitzka National Wildlife Refuge in 10 to 14 days.
"We feel like we're making progress we can actually feel. People are in a great mood," Joan Guilfoyle of the U.S. Fish and Wildlife Service said Tuesday from Meigs County, Tenn., northeast of Chattanooga.
The cranes, which are following ultralight aircraft, have nearly 500 miles to go but are making history with each state they cross. The species has not been seen in the wild in the eastern United States in more than a century.
There is a flock that spends time in Canada and Texas, but it could be wiped out by disease or a hurricane, scientists say, so establishing another geographically distinct population is critical.
Enter the ultralights. Cranes learn how to migrate from older generations, but since there are none in the East, human assistance is needed.
Even before they were hatched in a Maryland laboratory, the cranes were exposed to the sound of an ultralight. They spent weeks training to fly behind the crafts, which emit the recorded sound of a mother whooper.
The trip has been delayed several times by high winds and as of Nov. 3, the cranes had flown a mere 255 miles.
The trip began on Oct. 17 with eight whoopers, but one died when it escaped its pen during a nighttime windstorm and became tangled in a power line.
Another of the seven remaining birds has not been up to flying. It travels in a van, then spends nights with the other birds.
It had company on Monday. As the ultralight pilots made several large loops to gain altitude in order to clear a ridge, one of the birds turned back. It was recovered on the ground and driven to the site in Tennessee.
Despite earlier setbacks, the experiment has gone much better in recent days, with milder weather and smoother flying. The cranes have now covered more than 700 miles.
At 5 feet tall, whooping cranes are the largest birds in North America. Dan Sprague, a biologist who has worked with the whoopers "since they were eggs," said that means they can cover more ground in a day than most other birds. On several days, they've traveled 100 miles.
That is more than the sandhills, which made a trial run over the same route last year, but not nearly as far as they can travel on their own.
In wild migrations, cranes catch thermal air currents, rise to 8,000 to 10,000 feet, then glide. They might cover hundreds of miles in a day, then rest a few days in a cornfield. Flying behind the ultralights means the birds stay closer to the ground and tire more easily.
Crane Web sites