Bats More At Risk From Wind Turbines Than Birds, Study Claims
by Matthew McDermott, New York, NY on 08.26.08
Hoary Bat photo: Jerry Oldenettel
Based on past TreeHugger posts at least, the jury is still out on whether wind turbines really kill so many birds that we ought to overly worry about it. Well, a recent study published in Current Biology focuses not on the number of birds killed by industrial-scale wind turbines but on why more bats are actually killed than birds. The article doesn’t go into the numbers of bats which are killed but does provide evidence as to the cause of those that do. Science Daily provides the details:
Drops in Air Pressure, Not Blade Contact the Killer
Researchers from the University of Calgary say that 90% of the dead bats they examined showed signs of internal hemorrhaging such as could happen with a sudden drop in air pressure—a condition known as barotrauma. About 50% of the bats showed signs of physical contact with the turbine blades.
Report co-author Erin Baerwald:
Given that bats are more susceptible to barotrauma than birds, and that bat fatalities at wind turbines far outnumber bird fatalities at most sites, wildlife fatalities at wind turbines are now a bat issue, not a bird issue.
Bats are more at risk for barotrauma than birds due to the structure of their lungs: Bird lungs are more rigid than bat lungs and can withstand more easily a sudden drop in air pressure.
So Why Should We Care About Bat Deaths?
The majority of bats killed by wind turbines are migratory bats—hoary bats, eastern red bats, silver-haired bats—which eat thousands of insects per night (including crop pests) as the move from one region to another. Bat losses in one region could have negative effects on ecosystems far away from the site of wind turbines. Also, because bats have long lives and reproduce slowly, their ability to recover from population crashes is limited.
via :: Science Daily
Wind Turbines, Bird Deaths
Cats More Lethal to Birds Than Wind Turbines
Fatal Attraction: Birds and Wind Turbines
Common Eco-Myth: Wind Turbines Kill Birds
Thirsty for more? Check out these related articles:
- Creating New Jobs By Investing In Renewable Energy And Energy Efficiency
- We Want Renewable Energy & Green Jobs Too: Native American Groups Tell Obama
- UFO Octopus Destroys Wind Turbine?
- Wind Power Beats Nuclear & Clean Coal, Other Renewables As US’s Best Energy Option
Most likely the anti-windenergy folk will use this to reject all wind turbines. A more rational approach is:
1) identify bat migration pathways
2) determine when the bats will be where
3) shut down windturbines when bats are passing
(probably just a few days per year)
4) investigate why bats are attracted to wind turbines
5) develop something that makes that bats avoid wind turbines
That's interesting. So, would bigger turbines with slower moving blades help? Or maybe perhaps some ducting around the turbine to keep it from forming as many low pressure zones? Maybe a speaker could be added to produce ultrasonic sound to scare them away (Hopefully at a frequency that won't also bother dogs).
So I guess this might be the last nail in the coffin for those huge windmills. Mr. T. Boone Picken’s wind-farm will have a little more resistance –
http://www.treehugger.com/files/2008/06/why-wind-pickens-speaks.php.
What about vertical axis wind turbines (VAWT), I bet bats would avoid them.
Hardly a "last nail" Gleadall. Possibly, it's more likely a stinky, rotting Red Herring thrown into an open casket. And what makes you think that faster-spinning vertical turbines would be any safer to bats? Anyway, I can almost guarantee that the ecological impacts of wind energy are dramatically less than fossil fuel-based technologies.
But watch, you'll have all the fossil fuel pundits jump on this information and all the sudden sound like Greenpeace/Sierra Club Dreadlocked Hippies screaming how we MUST save the birds and bats from the HORRORS of wind energy!
"More than" a trivial number is likely still a trivial number.
The number of birds killed by wind turbines is trivial compared to numerous other natural and human-caused sources. The same probably holds true for bats, though the numbers weren't given (if they had been much worse than bird numbers, the number would have been shown). The only people that still hang on to this environmental myth are the right-wing media, who need straws to grasp at.
Simply put, coal kills far more humans and animals that a billion wind generators ever would.
it probably can be avoided if the windmills transmit noise at a ultrasonic frequency that warns the bat through its echo location capability.
Bad reporting.
Very bad reporting.
Where's the numbers? We know that bird death from windmills is a non-issue. I can assure you that far more birds have crashed into my house windows this year than are hit by windmills (
When you and Science Daily post that "bat fatalities at wind turbines far outnumber bird fatalities at most sites" you do information a disservice.
"Vastly more", couldn't that be as much as 100% more? Say less than 4 per year?
Or we talking a real problem?
And since we're talking mainly about migrating bats, if the problem is "real" then aren't we talking about turning off a few windmills during a few nights of the year when migrating bats are passing through?
And at night when we generally have excess energy production?
Aren't you guilty of feeding stuff to the anti-wind lobby?
@ Bob Wallace,
It's not TreeHugger or Science Daily that have not disclosed numbers. The original researchers did not either. If the original article was not a paid subscription I would have linked to it directly. All this research shows is that it is not impact which kills most bats, when they are killed by turbines, but air pressure changes.
If you're inclined to be opposed to wind farms, you could certainly use this (innaccurately in my opinion) to defend your position. Or you could see it as a warning that in some places and circumstances we may need to tweak how wind farms operate.
Your comments as to how to minimize this problem are spot-on.
Thanks "Huggs From The Heartland"
I agree with you about the fossil pundits jumping all over this, and the impact of fossil vs. renewable.
As for VAWT, I think that birds and bats will avoid the entire column of the VAWT because it is "solid".
They, VAWT, may have a greater angular speed but the tip speed will be less than those ROWT (regular old wind turbines) - I just made-up that acronym ;-}