Whooping cranes have waged a valiant fight against extinction, but federal officials warn of a new potential threat to the endangered birds: wind farms.
Down to about 15 in 1941, the gargantuan birds that migrate each fall from Canada to Texas now number 266, thanks to conservation efforts.
But because wind energy has gained such traction, whooping cranes could again be at risk — either from crashing into the towering wind turbines and transmission lines or because of habitat lost to the wind farms.
"Basically you can overlay the strongest, best areas for wind turbine development with the whooping crane migration corridor," said Tom Stehn, whooping crane coordinator for the U.S. Fish and Wildlife Service.
The service estimates as many as 40,000 turbines will be erected in the U.S. section of the whooping cranes' 200-mile wide migration corridor.
"Even if they avoid killing the cranes, the wind farms would be taking hundreds of square miles of migration stopover habitat away from the cranes," Stehn said.
The American Wind Energy Association says the industry grew by 45 percent last year, providing about 1 percent of the nation's energy.
It says its 1,400 member companies don't want their turbines, power lines, transmission towers and roadways to hurt the cranes, which are protected by the Endangered Species Act and the Migratory Bird Treaty.
"We would hate to see any collisions with whooping cranes," said Laurie Jodziewicz, the association's manager of siting policy. "It would be very distressing for everybody."
But Jodziewicz said the wind industry will continue to grow in the crane's migration corridor and should not be subject to regulations that don't apply to other industries.
Industry reluctant to change
"It's a very windy area," she said. "We certainly want to work toward minimizing impacts, but there is a real driver behind wind energy, which is the need for clean, renewable electricity.
"There are many other things going on in that corridor that could potentially affect that species. So to say that wind development should be stopped while allowing all sorts of other activities to continue might not be the right course of action."
Nicholas Throckmorton, a spokesman for the Fish and Wildlife Service, said the agency lacks the authority to demand that wind developers confer with it.
"There are no forced consultations," Throckmorton said, "other than pointing out that it's illegal to kill endangered species or migrating species."
Stehn and others say no whooping cranes have been killed by a wind turbine, though they remain concerned.
"In the natural world, birds and bats have gotten used to flying around a lot of things," Throckmorton said. "But nowhere in the natural world is there a big spinning rotor."
The wind industry has been criticized for its impact on other birds and wildlife, as well as its visual effect on the landscape.
Advisory committee created
The U.S. Department of the Interior has named a Wind Turbine Advisory Committee to make recommendations on how to avoid or minimize wind farms' impact on wildlife and habitats. The committee was scheduled to have its first public meeting Thursday in Washington.
There are three flocks of whooping cranes in North America, with a total of about 525 whooping cranes in the wild and in captivity. But the flock that migrates 2,400 miles from Wood Buffalo National Park in northern Canada's boreal forest to the Aransas National Wildlife Refuge near Corpus Christi, Texas, is the only self-sustaining flock. That means it is the species' best chance for survival, Stehn said.
Whooping cranes, the tallest birds in North America, fly at altitudes of between 500 and 5,000 feet — enough room to clear the turbines, which range in height from about 200 feet to 295 feet, and their blades, with diameters from 230 feet to 295 feet.
Landing, take-off are the issues
The problem, Stehn said, is that the cranes stop every night.
"It's actually the landing and taking off that's problematic," he said. "That's when they're most likely to encounter the turbines and transmission towers."
The most common cause of death for whooping cranes is crashing into power lines. Stehn said the industry could help by marking its power lines, which run from transmission towers.
"Each crane is precious when you only have 266," he said.