Wind farms could be killing 80,000 bats a year, new study finds
By Paul Homewood
h/t Phillip Bratby/Stewgreen
From the Telegraph:
Wind farms are probably killing tens of thousands of bats a year, even where risk assessments have been carried out to prevent the deaths, a study has found.
Researchers at the University of Exeter used sniffer dogs to locate the bodies of stricken bats near turbines to find out the scale of the problem.
A survey of 29 wind farms showed that 194 bats a month were killed, although the figure is likely to be higher because many of the dead creatures would have fallen prey to scavengers.
If the figure was extrapolated to all of Britain’s onshore wind farms it could mean that around 80,000 bats are being killed each year by turbines. The research also showed that the risk of bat death increased by 18 per cent for each extra metre of blade length. Some individual turbines were found to kill around five bats a month.
Dr Fiona Matthews, of Exeter University, who led the research, which was partly funded by the government, said operators should be encouraged to switch turbines off during peak migration and breeding seasons, such as summer nights.
The scientists think that bats may turn off their sonar when high up because they don’t expect anything to be blocking their path. They may also be attracted to insects which gather round the blades so an area that seemed clear in a pre-construction risk assessment could end up having any bats.
“An open field might not be very interesting, whereas once new structures are built the bats may investigate it or feed around it,” said Dr Matthews.
“It may be possible bats actually alter their behaviour once the turbines are built.
“Bats have been around for at least 30 million years and during that time have been able to fly happily without the risk of colliding with a spinning object.
“There are effective ways of preventing bat deaths. Unfortunately we have found that assessments conducted when wind farms are being planned are very poor at identifying whether a site is likely to be risky.”
The main casualties of wind turbines were two common species of bats: the Common Pipstrelle and Soprano Pipistrelle, tiny bats with reddish-brown coats and blackish-brown ears.
Bodies of the Noctule, one of the larger European bat species which sometimes come out before sunset to feed on moths, beetles and other large flying insects, were also found around turbines.
A dead Nathusius’s Pipistrelle, which has recently been found to be migratory, was also found, raising concerns about whether onshore and off-shore wind farms could pose a threat to their navigation route.
First author on the Current Biology paper, Dr Paul Lintott, said that although wind farms do kill bats it is important to remember the wider benefits of renewable energy in reducing greenhouse gas emissions and the positive impact that this will have on global biodiversity.
Dr Lintott said: “By focusing resources on stopping turbines during high risk periods we should be able to minimise the collision risk to local bat populations whilst also benefiting globally from the transition to a greener economy.”
The research, which was published in the journal Current Biology, was part funded by the Department for the Environment, and the Department of Energy and Climate Change.