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Windfarms pose major risk to bats

Windfarms are blamed for the deaths of large numbers of birds, including the threatened hen harrier, that crash into the spinning blades. But, what's now emerging is that bats are probably more at risk than birds. Up to now little has been known about the effects of windfarms on bats. Something that has mystified researchers, however, is that bats found dead around turbines had no visible injuries. So, are windfarms killing bats without touching them? It seems they are. ..."If bat fatalities continue this has the potential to be really serious. The problem is likely to get much worse with the proliferation of turbines, not just from large power companies erecting them but private individuals doing so as well," Ms Baerwald pointed out.

Windfarms are blamed for the deaths of large numbers of birds, including the threatened hen harrier, that crash into the spinning blades. But, what's now emerging is that bats are probably more at risk than birds.

Up to now little has been known about the effects of windfarms on bats. Something that has mystified researchers, however, is that bats found dead around turbines had no visible injuries. So, are windfarms killing bats without touching them? It seems they are.

Little research has been conducted into the issue in this country, which has up to nine species of bats. We we can only draw from studies abroad and the latest findings suggest a localised drop in air pressure caused by the whirling blades of turbines is causing the delicate lungs of bats to burst.

The US National Research Council published the results of a survey of US wind farms showing that two bat species accounted for 60% of winged animals killed.

In Ireland, the National Parks and Wildlife Service (NPWS) Action Plan for Bats 2008 also says the number of dead bats found under turbines is sometimes greater that the number of dead birds.

Until now, it was not... more [truncated due to possible copyright]  

Windfarms are blamed for the deaths of large numbers of birds, including the threatened hen harrier, that crash into the spinning blades. But, what's now emerging is that bats are probably more at risk than birds.

Up to now little has been known about the effects of windfarms on bats. Something that has mystified researchers, however, is that bats found dead around turbines had no visible injuries. So, are windfarms killing bats without touching them? It seems they are.

Little research has been conducted into the issue in this country, which has up to nine species of bats. We we can only draw from studies abroad and the latest findings suggest a localised drop in air pressure caused by the whirling blades of turbines is causing the delicate lungs of bats to burst.

The US National Research Council published the results of a survey of US wind farms showing that two bat species accounted for 60% of winged animals killed.

In Ireland, the National Parks and Wildlife Service (NPWS) Action Plan for Bats 2008 also says the number of dead bats found under turbines is sometimes greater that the number of dead birds.

Until now, it was not known how the bats died in Canada and the US. Because bats navigate using a sophisticated echolocation system, researchers thought it was unlikely they were getting caught in the turbines.

Lead researcher Erin Baerwald told Discovery News: "When people were first starting to talk about the issue, it was ‘bats running into the turbine blades.' We always said, ‘No, bats don't run into things.' Bat's can detect and avoid all kinds of structures."

In fact, they are even better at detecting moving objects, Baerwald said. "This kind of answers that mystery," she added. "It was something nobody could have predicted" When outside pressure drops, the bats' lungs expand and fill with blood and fluid - similar to drowning.

During the study - conducted at a windfarm in Alberta, Canada, over a two-year period - researchers found that 90% of the dead bats had internal hemorrhaging, while only 8% had external injuries and no internal bleeding.

Worries about effects on nature (though not always including bats) and the environment are among the main reasons for objections to windfarms.

That was the case in the Stacks Mountains area of Co Kerry, scene of a recent landslide. According to local man Joe Harrington, a rare hen harrier's nest was destroyed in the landslide.

In July 2004, Mr Harrington was among 12 people who wrote to EU Environment Commissioner Margot Wallstrom warning of threats to protected birds of prey should a windfarm proceed in the area. However, An Bord Pleanala still granted planning permission.

Meanwhile, Bat fatalities at wind turbines have been documented in Australia, North America, Germany, Spain and Sweden, but really the scale of the problem in Ireland and Britain has yet to emerge, as not enough research has been done.

Bats at risk of being killed by the growing number of windfarms could be saved with the use of radars, according to a new study in Scotland. Researchers at Aberdeen University examined the behaviour of bats at radar installations and found they did not forage where there was electromagnetic radiation.

Bat experts Prof Paul Racey and Dr Barry Nicholls studied bats at various distances from 10 radar installations across Scotland.

Prof Racey, of Aberdeen's school of biological sciences, said: "We found that the bats were deterred by the electromagnetic radiation emitted from the radar installations.

"This raises the possibility that radar could be used to deter bats from approaching wind turbines.

"And so far this would appear to be the only real possibility of preventing bats colliding with turbine blades worldwide."

Experts such as Erin Baerwald stress environmental assessment is required before windfarms are built. In Ireland, the NPWS advises planning authorities on the potential impact of developments on bats.

Ms Baerwald has found some of Alberta's tallest wind turbines pose few problems and kill just one bat a year, while poorly sited turbines can kill up to 31 bats a year. One study has estimated that as many as 110,000 bats could be killed each year in the eastern US by 2020 if solutions are not found.

"If bat fatalities continue this has the potential to be really serious. The problem is likely to get much worse with the proliferation of turbines, not just from large power companies erecting them but private individuals doing so as well," Ms Baerwald pointed out.

Meanwhile, there are ongoing surveys to determine the size and state of the health of the Irish bat population, irrespective of the windfarm situation.


Source: http://www.irishexaminer.co...

SEP 15 2008
https://www.windaction.org/posts/17105-windfarms-pose-major-risk-to-bats
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