Bats Avoid Radar Installations: Could Electromagnetic Fields Deter Bats from Colliding with…Turbines

[OKIsItJustMe]

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0000297

Bats Avoid Radar Installations: Could Electromagnetic Fields Deter Bats from Colliding with Wind Turbines?

Barry Nicholls*, Paul A. Racey

School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom

Abstract

Large numbers of bats are killed by collisions with wind turbines, and there is at present no direct method of reducing or preventing this mortality. We therefore determine whether the electromagnetic radiation associated with radar installations can elicit an aversive behavioural response in foraging bats. Four civil air traffic control (ATC) radar stations, three military ATC radars and three weather radars were selected, each surrounded by heterogeneous habitat. Three sampling points matched for habitat type and structure, dominant vegetation species, altitude and surrounding land class were located at increasing distances from each station. A portable electromagnetic field meter measured the field strength of the radar at three distances from the source: in close proximity (<200 m) with a high electromagnetic field (EMF) strength >2 volts/metre, an intermediate point within line of sight of the radar (200–400 m) and with an EMF strength <2 v/m, and a control site out of sight of the radar (>400 m) and registering an EMF of zero v/m. At each radar station bat activity was recorded three times with three independent sampling points monitored on each occasion, resulting in a total of 90 samples, 30 of which were obtained within each field strength category. At these sampling points, bat activity was recorded using an automatic bat recording station, operated from sunset to sunrise. Bat activity was significantly reduced in habitats exposed to an EMF strength of greater than 2 v/m when compared to matched sites registering EMF levels of zero. The reduction in bat activity was not significantly different at lower levels of EMF strength within 400 m of the radar. We predict that the reduction in bat activity within habitats exposed to electromagnetic radiation may be a result of thermal induction and an increased risk of hyperthermia.

…

Conclusions

We have demonstrated that bat activity is reduced in habitats exposed to electromagnetic radiation when compared with matched sites where no such radiation can be detected. However without access to detailed specifications of individual radar units (including operational times and operating frequency) it is difficult to quantify this relationship further. To more fully define the impact of radar on foraging bats, and ascertain its value as a potential source of mitigation, field trials involving a mobile radar that can be introduced into areas of known bat activity are now required. If the parameters of an RF signal capable of inducing an aversive response in foraging bats could be characterised then this may offer a method of mitigating bat collisions with wind turbines.

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[timeforpeace]

1. Since some electromagnetic radiation is produced by wind turbines, I'd say we're good to go.

[Dogmudgeon]

2. Big turbines don't turn that fast

As the size of the blades (or as anti-wind activists call them, "wind knives") increases, the slower they go. I would think that any self-respecting bat would have the ability to get out of the way of a wind knife moving at a velocity of one meter every minute.

On the other hand, cows might not be so quick to move out of the way. But seeing as how most cows don't fly, this is probably only a concern for animal rights advocates.

--d!

[Igel]

3. They do get out of the way.

Most of the bats killed by wind turbines are killed not by impact, but from having their lungs disrupted by strong pressure gradients.

It's the same with some kinds of bombs: It's not the shrapnel or flying debris that gets you, but the pressure wave. It might disrupt the brain, but even if your brain hasn't shut down your lungs have been ruptured in numerous places or even shredded so that you suffocate.

[old mark]

4. "Anti-wind activists?" Are there really such people? I am serious -

I never heard or even considered that there could be such a movement.
Amazing.....


markO8)

[kristopher]

5. Its an astroturf "movement" largely orchestrated by coal. nt

[old mark]

6. As if te coal people haven't got enough money out of us all over the

last century or so......


markO8)

[Dogmudgeon]

8. Umm ... you took that post *seriously*?

The part about the flying cows should have given it away.

--d!
Moo.

[timeforpeace]

7. Yep. Ruins their view. Some senator made a stink about them once.