Feeds

Wind turbines put bats under (low) pressure

Scientists probe barotrauma fatalities

Top three mobile application threats

A research team from the University of Calgary has found that a large percentage of bat fatalities at wind turbine sites are caused by a sudden drop in air pressure around the turbine blades, the BBC reports.

Reports of bat deaths at wind farms had previously been documented in Europe and the US, but quite why these generally exceeded the numbers of dead birds succumbing to the fatal blades had not been explained.

The Calgary team now says that while bats can use their echolocation to pinpoint the blades, they "cannot detect the sharp pressure changes around the turbine".

If a bat enters this zone, it can suffer "barotrauma" - internal haemorrhaging provoked by sudden expansion of the lungs* which puts pressure on surrounding tissue and bursts capillaries. Birds, which have more "rigid and robust" lungs, are less susceptible to the condition.

Lead scientist Erin Baerwald said: "An atmospheric pressure drop at wind turbine blades is an undetectable - and potentially unforseeable - hazard for bats, thus partially explaining the large number of bat fatalities at these specific structures."

To prove their case, Baerwald and colleagues examined carcasses of hoary and silver-haired bats dispatched by a wind farm in south-western Alberta. They found that while "fewer than half had external injuries that could have been caused by collision", 90 per cent demonstrated internal haemorrhaging, "most notably in the chest cavity".

The findings indicated that "wildlife fatalities at wind turbines are now a bat issue, not a bird issue", Baerwald concluded.

The EU acted on the bat slaughter two years ago, before the exact cause was known, and "formally agreed to make developers aware of the risks, and find ways of monitoring bat migration routes". Accordingly, a proposal earlier this to build a wind farm near Bideford in north Devon was rejected "because of the potential impact on the mammals".

The Calagary team's findings are reported in the journal Current Biology. ®

Bootnote

*Just to clarify, the sudden drop in pressure expands the air already in the lungs. As our diving expert Lewis Page put it: "If the bat remembers to exhale when passing a wind turbine it should be ok."

High performance access to file storage

More from The Register

next story
Most Americans doubt Big Bang, not too sure about evolution, climate change – survey
Science no match for religion, politics, business interests
KILLER SPONGES menacing California coastline
Surfers are safe, crustaceans less so
Discovery time for 200m WONDER MATERIALS shaved from 4 MILLENNIA... to 4 years
Alloy, Alloy: Boffins in speed-classification breakthrough
LOHAN and the amazing technicolor spaceplane
Our Vulture 2 livery is wrapped, and it's les noix du mutt
Liftoff! SpaceX Falcon 9 lifts Dragon on third resupply mission to ISS
SpaceX snaps smartly into one-second launch window
R.I.P. LADEE: Probe smashes into lunar surface at 3,600mph
Swan dive signs off successful science mission
Opportunity selfie: Martian winds have given the spunky ol' rover a spring cleaning
Power levels up 70 per cent as the rover keeps on truckin'
Elon Musk's LEAKY THRUSTER gas stalls Space Station supply run
Helium seeps from Falcon 9 first stage, delays new legs for NASA robonaut
Dragon capsule arrives at space station for Easter Sunday delivery
SpaceX reports Falcon booster made controlled touchdown in ocean
prev story

Whitepapers

Mainstay ROI - Does application security pay?
In this whitepaper learn how you and your enterprise might benefit from better software security.
Combat fraud and increase customer satisfaction
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Top three mobile application threats
Learn about three of the top mobile application security threats facing businesses today and recommendations on how to mitigate the risk.
3 Big data security analytics techniques
Applying these Big Data security analytics techniques can help you make your business safer by detecting attacks early, before significant damage is done.