Federal officials warned today that wind farms have become a potential new threat to the North American whooping crane population. Long endangered, the gigantic birds were once at a U.S. population of just 15 in 1941. Conservation efforts have restored the number to 266 today.
However, wind farms have become so widespread in the migration routes of the birds from Canada to Texas that the cranes are now at risk of death or injury from either crashing into large wind turbans and transmission lines or through loss of habitat from the 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, in an Associated Press report.
The agency estimates up to 40,000 turbines will be constructed in the 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,” said Stehn.
Whooping cranes are the tallest birds in North America, and fly at altitudes of 500 to 5,000 feet, high enough to clear the 200-300 feet turbines and their blades, with diameters from 230 feet to 295 feet. However, the cranes stop every night, and that is the problem, said Stehn. “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.”
There are three flocks of whooping cranes in North America, with about 525 birds in the wild and in captivity. However, the only self-sustaining flock is the one whose migration corridor spans 2,400 miles from Wood Buffalo National Park in northern Canada’s boreal forest to the Aransas National Wildlife Refuge near Corpus Christi, Texas. Stehn said the self-sustaining flock is the species’ best chance for survival.
Crashing into power lines represents the most common cause of death for the whooping cranes. 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 [in the U.S.],” he added.
Both the Endangered Species Act and the Migratory Bird Treaty protect the whooping cranes. However, the wind industry has been criticized for its impact on other birds and wildlife, as well as its visual effect on the landscape.
The American Wind Energy Association reported that the industry grew by 45 percent last year, and now provides about 1 percent of the United States’ energy requirements. It said its 1,400 member companies don’t want their turbines, power lines, transmission towers and roadways to hurt the cranes.
“We would hate to see any collisions with whooping cranes,” said Laurie Jodziewicz, the association’s manager of siting policy, in an Associated Press report. “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.
“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 Fish and Wildlife Service spokesman, said the agency lacks authority over the wind developers.
“There are no forced consultations,” he said, “other than pointing out that it’s illegal to kill endangered species or migrating species.”
Stehn and others said there have been no whooping cranes killed by wind turbines, but they worry this may change in the future.
“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 U.S. Department of the Interior has formed a Wind Turbine Advisory Committee, which held its first public meeting today, to make recommendations on how to avoid or minimize wind farms’impact on wildlife and habitats.
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