Don’t know so much about eagles per se, but millions of birds are killed every year by crashing into buildings and other manmade structures. Seems implausible, but it’s a known fact. Communications towers kill, according to conservative estimates, four to five million birds a year. The Fish and Wildlife Service (PDF cite here) says wind turbine rotors kill 33,000 birds annually.
Three-blade windmills typically have a tip-speed ratio of about 5. That’s the ratio of tip speed to wind speed.
From the Map of Available Wind Power on the Wind Energy page, even wind speeds that are “fair” are 14.3 to 15.7 MPH (presumably some sort of average value) which would correspond to a tip speed of 75 MPH. On good* days, with 20 MPH winds, the tips would be going 100 MPH.
- Maybe not good if you’re the eagle.
We have to remember to look at the big picture.
Wind turbines kill birds and bats. Solar affects desert habitat. Nuclear generates waste and is risky in urban areas. Hydroelectric kills rivers and fish.
But if we implement none of them, coal will slowly but surely affect the entire atmosphere, and along with it millions of animals and humans.
The effects of coal are diffused over decades, but in aggregate, the effects are inescapable and very, very difficult to work around. You may not immediately see eagle carcasses scattered all around a coal plant, but climate change will gradually and invisibly affect a lot more than a few hundred dead birds.
On the other hand, the effects of bird kills from a wind farm can be immediately seen and measured in a matter of weeks or months, giving opponents an easy target to rally around. The thing is, with good management, that species – and even just that one local population – can conceivably live on and thrive, something they cannot do if their entire habitat (or the habitat of other species in its food web) is affected by global climate change.
If we really care about the eagles (for example), we should be asking “Over the next few decades, will power-related animal fatalities increase or decrease following the mass adoption of alternative energy over coal?”.
An “incidental take” permit, as mentioned above, is not a blanket license to kill eagles for no reason. It’s a request to the government to kill X number of estimated eagles per year as a matter of operational necessity. The relevant agencies, in examining the overall environmental impact, would then weigh the estimated bird kills against other factors, such as their local population numbers and health.
If the incidental take is too high, they could request (or demand) mitigation efforts be undertaken: that can include everything from newer, slower blade designs that kill fewer birds, different tower designs that offer fewer perches (because birds like to perch up high and look for prey below, subsequently getting killed on their flight down), wide nets around the farm that deter birds, radar-assisted slow-downs or turn-offs (especially during migratory seasons), and other experimental techniques. In other words, thought of another way, an incidental take permit at least gets developers to think about these things in advance instead of just waiting for environmental lawsuits after the fact.
With modern “adaptive management” techniques, developers and permitting agencies can also re-examine the situation every X of years to see how the birds are being affected and then change the terms accordingly. Whether such restrictions are in place for this project (or at all common in Minnesota) I don’t know, but another article on the same development at least mentions that the project will require a bird and bat protection plan.
And just to clarify something in the OP: The permit is not so they can kill the eagles before the turbines get to them, but so that they can estimate and account for the estimated number of kills by the turbines.
Along with the permit, they are required to design and act according to a conservation plan for the affected species.
See US Fish & Wildlife Service: Incidental Take Permits and Habitat Conservation Plans
My bolding.
I don’t think you’re right about that.
Are eagles and other solitary predators at great risk from wind turbines? They can avoid other birds in the air, after all. I’d have though that the birds most at risk would be birds that fly in flocks. Any measure to keep all birds away from the wind turbines would be a good idea, and then maybe a get-out from the proscription on killing eagles.
But hey, with your username (especially taken as a whole), you should probably stay well away.
(Last post on this subject for a while. Sorry for the spam.)
I did a little bit more research.
Bald eagles and golden eagles, while majestic, are not really in much danger. In the US, they are not considered endangered by Fish & Wildlife. Internationally, their conservation status is that of “Least Concern”, the same status given to animals like pigeons, mosquitoes, and… humans. In fact, take permits are necessary not because of endangerment but because of the Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act, acts both intended to protect the species during times of crisis but which have not been updated since their populations rebounded.
Wikipedia says the primary danger to them is habitat destruction and loss of prey (and things like DDT in the past), all of which would likely be exacerbated by widespread climate change (my opinion).
So it seems to me that going against this wind farm due to its incidental take would be a sentimental sacrifice to the long-term viability of many species so that a few individual eagles can be protected in the here and now. Not sure that’s really a sound conservation strategy.
Look at this cat and eagle.
Especially at the end, when the catch takes a swat at it
Nitpic - They are wind TURBINES, not windMILLS. They don’t make grain into flour with them.
I actually did some work for a renewable energy company years ago.
The typical legitimate complaints against wind turbines are:
-Energy cost - on a per megawatt basis, they tend to be more expensive than other sources of energy
-Aesthetics - they are very pretty, but they are also HUGE. It’s like having a radio tower with spinning blades the size of a jumbo jet’s wings in your back yard. And they don’t just build one.
-Noise - they are also pretty loud.
-Fire - In spite of what this clips says, turbines catching fire are not a “freak occurance”.They are a regular occurance.
That they are a real danger to birds is largely BS. At least when compared to building any other large structure. Remember these structures are enormous. It’s not like the birds don’t notice them. And even at 100mph, the blades spin relatively slowly. So take the image of some sort of massive bird killing Cuisinart[sup]TM[/sup] out of your mind.
Wind turbines. The birds will learn to avoid them.
i was wondering if the eagle was tame or something, then i saw at the end that the cat has a backup.
Various googling suggests the speed can be considerably higher than that. From Wiki:
Definitely - plenty of them. Here’s an article from the LA Times about eagle kills in Altamont Pass:
buildings? what, why?
From your article:
Also:
Audubon’s Position on Wind Power
The article goes on to point out - and remember this is the bird society - that fossil fuel use is a much greater and imminent threat to birds and other wildlife than wind turbines.
Birds are not notoriously intelligent.
They do silly things, like fly into jet plane engine intakes.
Or into anything in their flight path, like a newly erected telephone pole.
They have no (or little) ability to correct for their normal flight paths.
This has been known for decades.
I say ‘birds’ but perhaps eagles (being oh so much majestic) are more intelligent.
I have not yet seen such a study,
I await such.
<Flies off to study eagles and attempt contact with them>
Hiiiiiiiiiieeeeeeeeeeeeee
I’m having a hard time making sense of those numbers. How are they averaging 67 deaths per year from so few birds to begin with? Are they predicting all the birds will be killed within two or three years?
The birds killed no doubt include transients that are not part of the local nesting population.
Oh, for pete’s sake!! Mankind has had windmills for centuries… was it that much of an issue then, or was it that it just wasn’t noted? I’m also having trouble understanding the definition of ‘incidental take’. When I see the words ‘seeking a permit’, it seems like they’re going to be hunting the birds… ‘To kill them to keep them from being killed’??? Give me a break. And why did they feel compelled to build their 18.75 acre site on an already existing home to nesting eagles?
Eyiyiyi :smack:
Reminds me of issues with the white tail deer here in Michigan. Seems the DNR determined we were overpopulated with the deer, so they were all herded into one of the local parks and the hunters were given a free-for-all.
OK… even given that, they want to kill them to keep them from being killed?? Why can’t the wind farms be built in other than agricultural areas, where the eagles are not likely to be nesting and feeding on the carcasses of farm animals?