Turbines and Bats: A Deadly Combo

  • Many bats are being killed by wind turbines (Photo courtesy of the US Fish and Wildlife Service)

The wind turbine industry has made
changes to reduce the number of birds killed
by the spinning blades. But scientists are
finding that more bats are being killed.
Rebecca Williams reports one research team
thinks it now knows why:

Transcript

The wind turbine industry has made
changes to reduce the number of birds killed
by the spinning blades. But scientists are
finding that more bats are being killed.
Rebecca Williams reports one research team
thinks it now knows why:

It’s been a mystery why bats are getting killed by wind turbines. They’re
usually great at avoiding collisions because they sense moving objects
even better than still ones.

A team from the University of Calgary looked at dead bats near
turbines. They found that 90% of the bats had internal bleeding.

Erin Baerwald is the lead author of the study. She says there’s a sudden
drop in pressure near the tips of the turbine blades. And when bats fly
close enough, the pressure drop makes their lungs over-expand and
burst. She thinks the bats are attracted to the turbines.

“Maybe they see these tall turbines as trees.”

That’s because most of the bats that are getting killed are tree roosting
bats.

Baerwald says researchers are looking at ways to change turbines to
avoid killing bats.

For The Environment Report, I’m Rebecca Williams.

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Barnyard Animal Extinctions

  • Milking Devon cattle are rare domestic breeds from an earlier day, some dating back to the 18th century. The animals hold genetic information that some people think is too valuable to lose. (Photo by Lester Graham)

When you think of endangered species, farm animals might not top the list. But some types of farm animals are in danger of going extinct.
Certain breeds of common barnyard creatures are no longer considered commercially viable, and are being allowed to die off. But as the GLRC’s Chris Lehman reports, there’s an effort to preserve some rare varieties of
livestock:

Transcript

When you think of endangered species, farm animals might not top the list. But some
types of farm animals are in danger of going extinct. Certain breeds of common barnyard
creatures are no longer considered commercially viable, and are being allowed to die off.
But as the GLRC’s Chris Lehman reports, there’s an effort to preserve some rare varieties
of livestock:


When you buy a pound of ground beef or a pack of chicken legs, you probably don’t
think about what kind of cow or chicken the meat came from. And in most stores,
you don’t have a choice. Beef is beef and chicken is chicken.


Of course, there’s many different kinds of cows and chickens, but most farmers stick with
just a handful of types. They prefer animals that are specially bred to produce more meat
in less time.


That’s all well and good if your motive is profit.


But some people think the move towards designer farm animals is risky.
Jerome Johnson is executive director of Garfield Farm Museum.


(Sound of turkeys gobbling)


Johnson says breeds like these Narragansett turkeys carry genetic traits that could be
desirable in the future. They don’t require as much food, for instance. That could be an
attractive feature as costs continue to rise:


“Some of the high-producing, high-yielding animals today, they may require a lot of
input. In other words, a lot of feed, more expense since so many things are derived from
petroleum, from the diesel fuel that powers the tractors to the production of fertilizer
and the like, and chemicals for herbicides and all… that as the cost of that goes up, it may
actually be cheaper to raise a different type of animal, that doesn’t require that much.”


Johnson also says some common poultry breeds get sick more easily. That’s part of the
risk farmers take when they choose meatier birds. Normally that might not be a problem,
but if Avian flu spreads to the US, some of the older breeds might carry genes that could
resist the disease. If those breeds disappear, that genetic information would be lost.


But some farmers choose rare livestock breeds for completely different reasons.


(Sound of baby chicks)


Scott Lehr and his family raise several varieties of pure-bred poultry, sheep, and goats on
their northern Illinois farm. These chicks are just a few weeks old…


(Sound of baby chicks)


“These are all pure-bred birds. These are birds that have been around a long time. Some
of the breeds that are in there, there’s Bantam Brown Leghorns, Bantam White Leghorns.”


Some of the poultry breeds are so rare and exotic they’re practically collector’s items.
Lehr’s son enters them in competitions. But the animals on their farm aren’t just for
showing off. Scott says they use the wool from their herd of Border Cheviot sheep for a
craft studio they opened in a nearby town:


“There’s quite a bit of demand growing for handspun wool and the rising interest in the
hand arts, if you will… knitting and spinning and weaving and those kinds of things… are
really beginning to come into, I guess, the consciousness of the American public in many
ways. It’s evolving beyond a cottage industry.”


And the wool of rare breeds like the Border Cheviot sheep is popular among people who want handspun wool.


(Sound of Johnson calling to giant pig, “Hey, buddy, how ya doin’?”)


Back at the Garfield Farm Museum, Jerome Johnson offers a handful of grass to a 700
pound Berkshire hog. This Berkshire is different from the variety of pig with the same
name that’s relatively common today. Johnson says these old-style Berkshires have a
different nose and more white hair than the modern Berkshire. They also tend to be fatter,
which used to be a more desirable trait.


The museum’s pair of old-style Berkshires are literally a dying breed. Johnson says the
boar isn’t fertile anymore:


“They were the last breeding pair that we knew of. These were once quite common but
now are quite rare. And we maybe have found a boar that is fertile that is up in
Wisconsin that was brought in from England here a couple years ago that we could try
crossing with our sow to see if we can preserve some of these genetics.”


(Sound of pigs)


Advocates of rare livestock breeds say the animals can be healthier and sometimes tastier
than the kinds raised on large commercial farms. And although you won’t find many
farm animals on the endangered species list, they could have important benefits for future
farmers.


For the GLRC, I’m Chris Lehman.

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