Over the last two years, researchers studied hundreds of bat carcasses found under wind turbines and dissected them to determine the cause of death. Supervised by U of C biology professor Robert Barclay, the researchers determined the majority of bats killed suffered from barotrauma­-- physical damage caused by a difference in pressure inside and outside the body. Barotraumas affect respiratory systems when air pressure suddenly drops, causing the lungs to over-expand. Only 10 per cent of bat deaths come from collisions with wind turbines.

German animal campaigners are alarmed by the number of dead bats being found near wind turbines and have called for restrictions on generators in areas with high populations of the nocturnal mammal. "The bats are not only being clobbered to death by the turbines, but can also suffer from collapsed lungs due to the drastic change in air pressure," said Hermann Hoetker of the Michael Otto Institute for wildlife and the environment.

Baerwald, whose team checks for carcasses under turbines at the Summerview wind farm near Pincher Creek, Alta., every morning, says bats are one of the unforeseen casualties in the rush to harness wind power. Several thousand of the tiny flying mammals are killed by the turbines each year across North America, with some farms much more deadly than others. Industry officials say they are determined to reduce the death toll but concede it is not going to be easy since so little is known about the nocturnal creatures. ...The researchers dissected 75 corpses and report that 90 per cent died form internal hemorrhaging consistent with "barotrauma," tissue damage caused by rapid or excessive change in air pressure near the rotor blades.

In the future, bat conservationists suggest, wind farms should be built away from known bat migration flight paths. The problem is: bat migrations are poorly understood at best. "We don't even know if they use migratory routes," Baerwald says, though she plans to begin looking for them in September. "We don't have a clear idea of what a bad site for wind turbines is in terms of bat fatalities," Cryan adds. "We're not to the point yet where we can suggest solutions." The full impact of these bat-killing pressure zones extends far beyond the wind farm, however. Such migrating bats travel from Canada as far as Mexico, eating thousands of insects en route, including crop pests such as moths and beetles.

Bats are dying as they fly into low-pressure zones around wind turbines. The sudden low pressure causes the air in their lungs to expand and cause tissue damage, called barotrauma. Low-pressure area: most severe immediately out from the blades and decreases as it gets closer to the centre of the turbine. There is also a low-pressure area down the shaft.

Sudden air pressure changes around wind turbines is likely behind the large numbers of migratory bats found dead in southern Alberta, according to a new University of Calgary study. The two-year study found 90 per cent of the studied bats found dead below turbines near Pincher Creek suffered severe injuries to their respiratory systems consistent with a sudden drop in air pressure that occurs near the turbine blades.

With their amazing flying and hunting abilities, bats are major predators of insect pests. But surprising numbers of bats are being killed at wind energy sites. Biologist Erin Baerwald just couldn't believe that these adept, radar-equipped flyers were simply flying into the blades. Now her research has proven her right. "We always correct that way of thinking, saying, ‘No, no, the turbines are colliding with the bats,'" Baerwald says. "But this has really changed the way we think about it, in that the bats aren't colliding with the turbines, the turbines aren't colliding with the bats. It's actually an undetectable hazard."

Canadian researchers have found wind turbines can kill bats without them actually flying into the blades. ..."An atmospheric drop in pressure at wind-turbine blades is an undetectable - and potentially unforeseeable - hazard for bats, thus partially explaining the large number of bat fatalities at these specific structures," said Baerwald.

About 140 people got another look at the coming world of wind power Friday. Birds and bats were major topics, but the basic message was that there needs to be more study of the impact of wind farms and turbines. "We're kind of finding our way along with the industry," Kathy Boydston, a biologist with Texas Parks and Wildlife Department, told the gathering at the Ambassador Hotel in Amarillo. Experts are trying to find ways to deter birds and bats from hitting turbines, but the lack of information on how many fall victim and how it happens is lacking.

David Parrish, reassigned from Magic Valley regional supervisor to Boise as fisheries program coordinator, wrote in a letter to The Times-News on July 6 that the 185-turbine China Mountain wind farm "will have negative repercussions on Idaho's wildlife." "It's a no-brainer - the footprint of a project that will cover prime habitat (for) sage grouse, mule deer, antelope and other sagebrush dependent species," Parrish wrote.

Two years ago, PPM commissioned a study to learn how many bats could be affected by its proposed wind farm. Biologists hung nets for two nights in 10 locations and caught 138 bats. Cale calculates that if 24 nets -- that's one for each turbine -- were left up through the 14 combined weeks of seasonal bat migration, more than 16,000 bats would be caught. Each net covered an area of about 1,000 square feet. That compares to 66,000 square feet carved out by a turbine's rotating blades. "It's going to be a slaughterhouse," Cale said.

An estimated 1,200 bats, most of them probably just passing through Montana, were killed after striking wind turbines at the Judith Gap Wind Farm between July 2006 and May 2007, according to a post-construction bird and bat survey. The number surprised Invenergy, which owns the farm, as well as government and private wildlife experts. "It's killing 1,200 bats a year and that's a lot more than anybody anticipated," said Janet Ellis of Montana Audubon, a bird conservation group. ...The study estimates that 406 birds, or 4.52 birds per turbine, were killed during the study period.

The company is seeking an incidental take permit from the U.S. Fish and Wildlife Service and has prepared a draft habitat conservation plan and environmental assessment to minimize the effects on the endangered Hawaiian petrel ('ua'u), the endangered Hawaiian stilt (ae'o), the endangered Hawaiian hoary bat ('ope'ape'a), and the threatened Newell's shearwater ('a'o). Six of the seven 165-foot towers already have been built on land owned by Castle & Cooke. The company plans to build the remaining tower and operate all seven for a period of up to two years to collect data on wind patterns, according to permit documents.

Researchers studying birds killed by power lines are encouraged by recent findings from a study in the Dakotas that could hold implications throughout the Central Flyway, the major migration route that stretches from Canada to Texas. Wildlife deaths from power lines, wind turbines and other structures are a growing concern across the country, said Al Manville, a senior wildlife biologist with the U.S. Fish and Wildlife Service. More transmission lines and wind turbines are planned in coming years, which could put several bird species at risk, Manville said. ...Research is important, partly because "birds play a key role in the ecosystem," said Greg Butcher, director of bird conservation at the National Audubon Society.

Marty has been studying the life cycle of the timber rattlesnake for 25 years. He regularly visits several dens that have been in existence on the Allegheny Front for thousands of years -- to check on the emergence of snakes in the spring. Marty had been concerned about the possible disruption of the snake dens by the construction of the Ned-Power Industrial Wind Turbines, but he was assured that the dens, located in rock piles, with crevasses going into the earth, would not be disturbed. When Marty returned to his study site this Spring, this is what he found: "It is finished. There is nothing left to save.

A regional conservation group is pointing out where birds and wind farms might not mix. A Playa Lakes Joint Venture mapping project shows the few remaining acres of habitat for the lesser prairie chicken and where playa lakes can draw large numbers of migrating birds. "There has been a lot of interest from the wind industry, local and state conservation groups and state agencies," said Megan McLachlan, a geographic-information system analyst for the group. "We've gotten a lot of phone calls the last couple of months asking us to share the data. There's a lot of people working on the issue."

As wind power gears up in Montana, the effects of large-scale wind projects on wildlife remain a concern: Birds may be in the clear, but bats are running into trouble. Turbine-related fatalities at Judith Gap Wind Energy Center near Harlowton were 1,206 bats and 406 birds, according to a 2007 preliminary study prepared by TRC Solutions' Laramie, Wyo. office. Roger Schoumacher, a biologist and consultant for TRC, said the bat fatality count is higher than what generally occurs in the West.

Iberdrola Renewables is considering options for Horse Creek Wind Farm about two weeks after it told the Clayton Planning Board it was suspending its application. While the company insists it was an internal decision, its representative did admit that the nearby Indiana bat population was a consideration. Indiana bats are an endangered species and there is a hibernation spot near the proposed wind project. The bats also have been affected by white nose syndrome, the mysterious ailment that has killed thousands of bats. The loss of the endangered species to disease has made federal wildlife experts even more sensitive to losses induced by man.

The prospect of thousands of endangered bats flying to their deaths in West Virginia wind turbines soon could get consideration in federal court because of Judy Rodd. The 63-year-old is the president of Friends of Blackwater Canyon, which recently joined 10 other groups in filing a "notice of intent" with the Fish and Wildlife Service to sue a wind company on Endangered Species Act grounds. The organizations warned of potential turbine kills of the Indiana bat, Virginia big-eared bat and Virginia northern flying squirrel. "Yes, we're concerned about climate change," said Rodd in a phone interview. "But that doesn't mean they can't build the turbines somewhere else and let the bats live."

Diane Winn doesn't dispute the need for clean, renewable energy -- the kind provided by wind turbines and hydroelectric dams. But Winn and Marc Payne, her partner at Avian Haven Wild Bird Rehabilitation Center, are all about saving injured or abandoned wild birds. Wind turbines provide clean energy, but birds often die when they fly into turbines, and the noise the machines make can disrupt bird and human alike. For those reasons, Winn and Payne say they would close their North Palermo Road facility if Beaver Ridge Wind, an affiliate of Competitive Energy Service, builds three electricity-generating wind turbines on nearby Beaver Ridge. "No one argues with the basic fact that turbines kill birds," Winn said. "The only issue is how many are killed, and whether those numbers impact species populations."