Thursday, May 06, 2010

A Murder of Crows

murder_of_crows This isn’t a cozying up to wind post, but rather a how not to use numbers to make an argument post.

We were listening to a Senate hearing this morning and Senator Lamar Alexander (R-Tenn.) mentioned that wind turbines kill a lot of birds. He said this as a kind of aside about the problems of  electricity generators other than nuclear.

We have no idea why this idea has popped to the fore, but we’ve heard a lot of it lately. Here’s George Will on ABC’s This Week:

"By the way, wind farms kill a lot more birds daily than are probably going to be killed in this oil spill."

Well, yes and no – windmills don’t cause ecological disasters and those tend to be devastating to the future of a species, bird and otherwise.

Will had expanded on this comment in his Newsweek column a few weeks ago:

Wind power involves gargantuan "energy sprawl." To produce 20 percent of America's power by wind, which the Obama administration dreamily proposes, would require 186,000 tall turbines -- 40 stories tall, their flashing lights can be seen for 20 miles -- covering an area the size of West Virginia. … And birds beware: the American Bird Conservancy estimates that the existing 25,000 turbines kill between 75,000 and 275,000 birds a year. Imagine the toll that 186,000 turbines would take.

275,000 birds? Here’s Mrs. Bundy, the ornithologist in Alfred Hitchcock’s The Birds (1963), when asked why it is a doomed task to wipe out all the birds in the world (which in the movie are attacking humans):

Because there are 8,650 species of birds in the world today. It's estimated that five billion, seven hundred and fifty million birds live in the United States alone. The five continents of the world probably contain more than a hundred billion birds! [The current best estimates are between 200 and 400 billion birds worldwide.]

In point of fact, birds had to adjust to a creature determined to put large obstacles in their way a long time ago. We have no idea how many birds smack into cooling towers or nuclear plant buildings around the world – likely a smaller number than windmills, but some certainly. Birds will run into just about anything.

Will uses the American Bird Conservancy (cool group – worth a visit)as his reference, but fails to include other approximate annual bird kill counts the conservancy has compiled. Media Matters for America put a list together based on conservancy data:

Building strikes - 100 million - 1 billion

Car strikes - 200 - 300 million

Communication towers - 4 - 50 million

Power lines ~ 75 million

Cats - 365 million (1 million per day)

Wind farms - 100,000 - 300,000

Conclusion: context is all. One could very well decide that putting wind farms where they have to go – windy places – is too damaging to bird migration paths or is home to a nearly extinct species of bird – or other critter, for that matter. And that would be that.

But the number itself is not compelling. Looking at the American Bird Conservancy’s site, you’ll quickly learn that disease and rapid land development are far more effective bird killers than a structure (nuclear plant) or series of structures (wind farms).

This one’s a non-starter.

The origin of a murder of crows (or parliament of rooks, for that matter) is not known. It may be based on a folk myth that a flock of crows will “murder” members if it grows too large, but that hasn’t actually been observed to happen. Wikipedia has a list of these grouping terms.

8 comments:

Phil said...

It is my understanding that wind energy kills -specific types- of birds in large quantities.

It is the large predatory birds, hawks, eagles, vultures, that are disproportionately killed by wind turbines.

It can be difficult to quantify, because the birds aren't killed immediately, they are often fatally wounded. They then proceed to die far enough away from the turbine which caused their death to not be counted.

I do not think it is proper to count Sparrows and Starlings as the same as Golden Eagles. Sure a Sparrow dies, and a Golden Eagle dies and they each count as one bird, but the overall effect on the local ecosystem from the loss of large raptors can be devastating.

Lots more information, commentary, and good links to Californa studies: http://answers.google.com/answers/main?cmd=threadview&id=120272

Anonymous said...

George Will is trying to be alarmist about bird kills...but his own statistics show that each large wind turbine kills at most an average of 11 birds a year. That's hardly a wildlife catastrophe. One would expect that many birds would probably run into any large structure annually.

(25,000 turbines kill as many as 275,000 birds/yr, Will says)

Brian Mays said...

From the Media Matters link:

"In the May 3 interview, [American Bird Conservancy director of Public Relations Bob] Johns, told Media Matters that the number of birds killed by the oil spill in the Gulf of Mexico depends on when the well is capped. Johns stated: '... we don't know when the well will be capped. The longer to it goes on, the more birds that will be killed. If the well is capped now, the number of birds killed will be in the tens of thousands.'"

Tens of thousands?! Oh my!

Can you imagine what would happen if an oil company executive tried to spin this by pointing out that cats kill one million birds (10 to 100 times as many) each and every day?

It's amazing what wind advocates are able to get away with. Truly amazing. Of course, you won't see Media Matters calling them on it. They're too busy "debunking" George Will's article by pointing out that the figures that he cites are, in fact, correct.

Mr. Will would be amused.

Marcel F. Williams said...

The problem with wind turbines is that they tend to kill predatory birds and bats. The population of predatory birds is a lot smaller than non predatory birds. And these are the birds that prey on the pest (rodents) that eat our crops and spread diseases to humans.

Bats feed on mosquitoes, the number one animal killer of humans on Earth thanks to the mosquitoes' ability to spread disease to humans.

DocForesight said...

@Anon -- It seems to me that Mr. Will is trying to place the numbers of bird kills, the energy resources and power generation into context.

Yes, birds fly into buildings-usually glass-sided. Birds normally avoid flying into stationary objects which don't also confuse their sense of sight (non-glass). The wind turbines moving props are what strike the bird -- perhaps they can't judge the movement and timing?

As Phil states above, it's the raptors that contribute to the greatest loss in value to the food chain due to their comparative lower population.

Finrod said...

The NEI can sing the praises of wind power all it likes, but the independent pro-nuclear blogging community long ago recognised wind power for the fraud that it is. They have provided the facts, figures and polemics to undermine wind's credibility in the past, and shall doubtless continue to do so in the future.

Flan Mannagan said...

Clearly, anyone promoting big wind power is a faux environmentalist. A destroyer of the natural world pretending to be a savior.

Promoting non-solutions such as big wind power is a good way to kill off a substantial part of the human population.

For all the dieoff lefticons out there who want 90% of all humans to die, to make way for their post-dieoff lefticon utopia, it might be best for you to take the plunge yourself. The rest of us will be along presently.

Anonymous said...

Big wind power will kill 90% of the human population? Did I read that correctly?

And some posters here accuse antinukes of exaggerated fearmongering...