Feeds

Wind turbines put bats under (low) pressure

Scientists probe barotrauma fatalities

Secure remote control for conventional and virtual desktops

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."

Next gen security for virtualised datacentres

More from The Register

next story
Gigantic toothless 'DRAGONS' dominated Earth's early skies
Gummy pterosaurs outlived toothy competitors
Vulture 2 takes a battering in 100km/h test run
Still in one piece, but we're going to need MORE POWER
TRIANGULAR orbits will help Rosetta to get up close with Comet 67P
Probe will be just 10km from Space Duck in October
Boffins ID freakish spine-smothered prehistoric critter: The CLAW gave it away
Bizarre-looking creature actually related to velvet worms
CRR-CRRRK, beep, beep: Mars space truck backs out of slippery sand trap
Curiosity finds new drilling target after course correction
'Leccy racer whacks petrols in Oz race
ELMOFO rakes in two wins in sanctioned race
What does a flashmob of 1,024 robots look like? Just like this
Sorry, Harvard, did you say kilobots or KILLER BOTS?
NASA's rock'n'roll shock: ROLLING STONE FOUND ON MARS
No sign of Ziggy Stardust and his band
Why your mum was WRONG about whiffy tattooed people
They're a future source of RENEWABLE ENERGY
prev story

Whitepapers

5 things you didn’t know about cloud backup
IT departments are embracing cloud backup, but there’s a lot you need to know before choosing a service provider. Learn all the critical things you need to know.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Build a business case: developing custom apps
Learn how to maximize the value of custom applications by accelerating and simplifying their development.
Rethinking backup and recovery in the modern data center
Combining intelligence, operational analytics, and automation to enable efficient, data-driven IT organizations using the HP ABR approach.
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.