Explaining Wind Turbine Lethality

Guest Post by Willis Eschenbach

For reasons that will soon be evident, the comments on my previous wind turbine post reminded me of a long-ago sunset dinner with my gorgeous ex-fiancée on the verandah of a lovely treetop restaurant on Pohnpei island in the tropical Pacific.

The only “fly in the ointment”, as is often the case in the tropics, was … the flies. And various other tropical flying insects. So the owners had thoughtfully installed one of those insect electrocution devices with the exposed power wires that go BZZZT every time another fly hits the wires, is electrocuted, and falls out of the sky.

In the lovely twilight, I thought little more about the occasional BZZZT! of the fly-killer until the owner of the restaurant said, “You should look over the edge of the verandah.”

We stood up, went to the edge, and looked down. And way down there on the ground, in the gathering darkness, was a group of very large tropical toads gazing straight upwards … and as we gazed down at their toadiness, BZZZT! went the fly-killer. 

The freshly barbecued corpse of the fly fell straight downwards … but it never made it back to the earth …

I realized then that in nature nothing goes to waste. There’s always something waiting to consume any form of food, at times before it even hits the ground.

I bring this up because I’ve been thinking about the unexpectedly lethal habits of wind turbines. In the US, if someone kills a bald eagle they get slapped with a big fine … but wind turbines can kill the national bird, the Bald Eagle, by the dozens and absolutely nothing happens to them. They kill so many birds and bats that the US government has had to give them special exemption from all environmental rules and regulations about bird and bat deaths … and that’s a lot of deaths. It’s bizarre just how lethal wind turbines are.

So for example, it’s estimated that the wind farm at Altamont Pass in California not far from my home has killed 2,900 golden eagles in the quarter-century since it was built … and that’s just golden eagles. And estimates are that 600,000 bats are killed annually in the US alone.

I was thinking about my evening in the Pohnpei restaurant because someone said to me on Twitter “But … but … cats and tall buildings kill lots of birds, too” … and it’s a fact, they do. 

However, there’s a huge difference with wind turbines, and I say that the difference, curiously, is bugs. Here is my theory as to why wind turbines kill so many bats and birds big and small, many more than anyone expected.

Wind turbines are surprisingly lethal because they kill bugs.

And not just a few bugs. Based on observations and model calculations, German researchers calculated that each wind turbine kills on the order of 12,000 insects per day, which is some 1,200 tonnes of dead insects per year in Germany alone. And for each bug that is killed, perhaps ten bugs are injured or dazed. Plus I suspect their calculations are too low. 

First, a bit of background. Most folks don’t realize that the tips of those big slow-turning wind turbine blades are typically moving at 175 miles per hour (280 km/hr, an average of 21 different models), with some going as fast as 230 miles per hour (370 km/hr). YIKES! There’s no way to dodge something moving that fast.

It gets worse. At that speed, the blade tip doesn’t even have to hit an insect, bird, or bat to kill it or daze it. There is a near-vacuum on the back side of the blade. Just going suddenly from normal pressure to near-vacuum can cause a variety of injuries, including bursting the lungs of bats and birds.

So let’s follow the story, starting with the bugs. The turbine is acting like a giant bug-mincer. It is smashing bugs on the leading edges of the blades, just like the smashed bugs you get when you drive down the highway. It is injuring bugs through both turbulence and pressure changes. And it is constantly and invisibly spinning hundreds of both dead and wounded bugs, and lots of smelly bug-juice from the smashed insects, up into the sky.

What happens first, of course, is that the smell of the dead and wounded insects attract lots of other insects. Many insects are scavengers, and so more insects come to feed on the dead insects just like flies drawn to sh … well, you get the idea. So in addition to the bugs killed and wounded, we have all of the other very live bugs eating on them, and flying around between meals.

Now, remember what I said about the frogs eating the flies “before they hit the ground”? What happens next is that large numbers of both bats and insectivorous birds are drawn by the smell of thousands of dead and wounded insects. They do their very best to eat the dead and wounded insects before they hit the ground.

And when you mix large numbers of bats and insectivorous birds on the hunt, somewhat oblivious to their surroundings in pursuit of insect prey, with turbine blade tips going 230 miles an hour, that’s 370 km/hr, the outcome is unavoidable—large numbers of dead and wounded bats and birds.

Of course, wherever you have large numbers of dead and wounded bats and birds, you’ll inevitably attract numbers of the large predatory or scavenging birds such as owls, buzzards, vultures, falcons, eagles, kites, buteos, accipiters, and harriers. They come in to eat the living, wounded, or dead birds and bats that came in to eat the living, wounded, or dead bugs … and of course, since these large predators too are on the hunt and somewhat oblivious to their surroundings, when you mix in the high-speed turbine blades the raptors suffer the same fate as the smaller birds, the bats, and the thousands of bugs. Killed and wounded.

How many birds die this way? The simple answer is … too many. But it’s hard to tell because the wind industry folks consider that a trade secret, and they won’t reveal their figures. The Audubon Society says:

Wind turbines kill an estimated 140,000 to 328,000 birds each year in North America.

Hundreds of thousands … however, this is just a guess, and the guesses keep getting revised upwards. In Hawaii, one of the few places where they’re legally required to measure the losses, I find articles like this one from 2017, “Wind farms killing more bats than expected“, or this one, “Hawaii windmills take a toll on endangered animals

Right … I bet they are killing more than expected …

Me, I say that the reason people continually underestimate the number of birds and bats killed by wind turbines is that they never thought about the bugs. They think that a random bat or bird will only intersect with a turbine blade every once in a while as it flies through the landscape, so not many will die … they don’t realize that instead, the bats and birds are attracted to the turbines by an unending supply of easy insect prey. Those birds and bats, in turn, are preyed upon by raptors of all types … and all of them are chasing one of many dead or injured insects, birds, or bats through the lethal turbinespace, with the tragically predictable outcome.

Anyhow, that’s my own theory of why wind turbines kill so many birds and bats—because of bugs. Go figure. As always, YMMV.

Here, I’ve been packing. I’m leaving tomorrow for a couple-week vacation in the Nevada desert, so I’ll be out of touch with you good folks for a bit.

Sea fog is rolling back in, stay well,


4.2 6 votes
Article Rating
Newest Most Voted
Inline Feedbacks
View all comments
Al Miller
August 21, 2019 10:11 am

It’s hard to imagine what is good about “updating” an archaic technology to meet the demands of a society that has moved so far beyond windmills.
There are so many negatives about windmills that, and frankly I’m appalled at the silence of the “greens” on this one, it would be completely asinine to continue down this path, yet here we go…

Bryan A
Reply to  Willis Eschenbach
August 21, 2019 12:31 pm

There is yet another, and in my opinion far greater factor in bird mortality in comparing Wind Turbines to any other cause (Buildings, Windows, Cars, Cats) Exposure Potential.
Tall Buildings world wide count in the hundreds of millions.
Building Windows world wide count in the Hundreds of Billions and likely Trillions.
Cats number in the Hundreds of Millions.
Cars topped 1.2 billion globally last year.
Wind Turbines number in the hundred thousand only.

Tom Kennedy
Reply to  Bryan A
August 21, 2019 2:24 pm

Michael Shellenberger – a former proponent of wind turbines wrote:
“As for house cats, they don’t kill big, rare, threatened birds. What house cats kill are small, common birds, like sparrows, robins and jays. What kills big, threatened, and endangered birds—birds that could go extinct—like hawks, eagles, owls, and condors, are wind turbines.

In addition the fish and wild life service has reported that:
Collisions with wind turbines and white‐nose syndrome are now the leading causes of reported Mass Mortality Events (MMEs) in bats.

In addition several species of bats are threatened with extinction in Hawaii and other areas
Bats are the best natural way to provide mosquito control.


GREG in Houston
Reply to  Tom Kennedy
August 21, 2019 6:13 pm

The buildings are not moving at 200+ mph.

Reply to  Bryan A
August 21, 2019 2:32 pm

Bryan A

Buildings, and windows are static. Birds have an instinctive ability, like you, not to dive into something solid. When was the last time you walked into a window 20 stories up?

Animals, generally, have also evolved (pretty quickly) to avoid roads and cars otherwise our tarmac would be plastered in wildlife. Foxes, Badgers, hedgehogs are largely nocturnal animals and avoid lit, or car headlight contaminated roads at night.

Cat’s are more likely to be prey to a reasonable sized raptor than a predator. And small birds are good at avoiding them. Cat’s also predate on the winged predators that cannibalise birds nests, so there is a reasonable balance in nature.

Wind turbines, on the other hand, are virtually invisible to a bird. They are scything away, night and day, with blades a small fraction of their destructive capabilities.

Nor am I a great believer in the ‘bird chopper’ syndrome. Personally, I think there are far better arguments against turbines than stooping to the emotional level of the green lunatics.

Having said all that, I believe there are bird counts under land based wind turbines that are concerning.

In practical terms, mathematically speaking, roughly the entire continent of the United States would have to be covered, wall to wall, in wind turbines just to keep up with the 2% of global growth in demand for electricity by 2050.

That’s not even dealing with our existing demand, just growth.

How many birds will that cost? And if I’m sceptical of today’s claims, I’m pretty convinced not many birds will be flying when the USA is covered in turbines.

Roger Knights
Reply to  HotScot
August 21, 2019 5:59 pm

“someone said to me on Twitter “But … but … cats and tall buildings kill lots of birds, too” … and it’s a fact, they do.”

But likely not nearly as many as has been assumed from the number of dead birds pussycats dump on their owners’ porches. Millions of birds die of natural causes. Cats will come upon them and carry them home on instinct. I suspect that these constitute a majority, perhaps a large majority, of the cat-carnage total.

Reply to  HotScot
August 23, 2019 8:18 am

Not sure where you live, but there are dead fox cubs littering country roads and highways every fall where I live. And there are lots of whitetail deer corpses along the highways as well. I had a bluebird fly into the glass of my kichen window early this summer and die. I am not disagreeing with the premise that too many birds and bats are being killed by wind turbines, BUT your understanding of wildlife vs vehicle encounters needs work.

Nicholas McGinley
Reply to  HotScot
August 23, 2019 2:10 pm

For the numbers suggested by apologists for birds killed by buildings, cars, cats, and power lines, you yourself and everyone you know would have birds flying into your window and dying on an ongoing regular basis, several times a year, you would hit one or two with you car, and so would everyone else, one or more times every year…so for every few hundred cars on the road, one is hitting a bird that day. There would have to be dead birds on every miles of every major road every single day, and everyone would have had to have killed more birds with their car than years they have driven.
Hundreds and hundreds for truckers and people who drove all day.
Every house and building you have ever been in would be struck frequently and dead birds lying on the ground would line the sidewalks of major cities.
Several percent of all the people and hence windows in the country are in places like Los Angels and New York, so that means thousands and thousands of birds are hitting windows in this cities every day.
And every day, in every county, hundreds of birds short out power lines and transformers. If you every heard what it sounds like when distribution level voltage is shorted by a nonconducting object, it causes what is know as an arc blast, an explosion of vaporized metal in the thousands of degrees that is literally like a stick of dynamite in effect and sound. Several per hour, ten or more, in every county, everywhere, all the time.
IOW…it is [snipped. Language.]. There are no cities of ninja cats. There are not birds hitting buildings everywhere, all the time, there are not birds being killed at such a rate it is one or more per person per year for everyone on the road…
Nothing like those things are true, because the numbers were made up out of thin air and make no sense…it is impossible for them to be true.
How often does a bird hit a window and die at your house?
How many birds have you hit with your car this year, and over your lifetime? How often do you see a bird hit?
Maternity ward nurses swear on a stack of bibles that more babies are born on a full moon than any other night.
But birth records are the most accurate and complete records in the world, and it is clear there is no monthly pattern. It is because of confirmation bias.
Everyone has seen road kill.
Does it follow logically that whatever number some liar made up, and no one ever bothered to confirm or contest or check for themselves, must be true? Or any approximation thereof?
I can promise you…the answer is no.
No one knows these numbers, but for each of them, the true number is far lower. For some of them, the actual number is a tiny fraction, less than 1/100th of the reported number, perhaps far less then that.
Because these numbers are just made up.

Reply to  Bryan A
August 21, 2019 4:41 pm

When in trouble, just make up big numbers.
I call total BS on your claims regarding the number of birds killed by buildings, windows, cats and cars.

michael hart
Reply to  MarkW
August 21, 2019 7:27 pm

I too am skeptical about anybody’s current ability to put accurate numbers on these things.

What is not in doubt, is that the usual suspects don’t appear to even care to find out, despite their professed love for the environment and non-human creatures.

I guess I shouldn’t be surprised though. Greenpeace is completely antithetical to the one thing (CO2) that, despite mankind’s worst efforts, is unequivocally and peacefully making the world a greener place. It’s staggering how much hypocrisy can be bought with an annual budget running into hundreds of millions of Dollars.

Bryan A
Reply to  MarkW
August 22, 2019 12:45 pm

I have been driving …
for more than 40 years
in more than 18 different cars and trucks
for more than 1,200,000 miles
and have yet to ever hit a bird while driving on any road across 5 different states.

Nicholas McGinley
Reply to  MarkW
August 22, 2019 2:23 pm

Mark, Michael, Brian,
Ditto to all of these comments and observations.
These numbers on cars, cats, buildings, and power lines are pure BS.
Never hit a bird in well over 1.5 million miles of driving, never heard from anyone that did, except one time, and I recall it well.
Never saw a bird hit.
Have seen in my life a few birds killed or dead here and there, including a few road kills.
From what we know must be true of the number of birds in the wild, and how long they live, birds are dying all the time in many ways. Most born wildlife never reaches adulthood, or simply by the breeding rate the numbers of any creature would skyrocket very quickly.
A breeding pair of songbirds have between 25 to 50 + offspring (or eggs laid but not necessarily hatched or fledged) a year under ordinary conditions. And they live from 1-5 to well over ten years on average, if not killed. Seabirds are known to live 20-40 years and upward from there.
What we know for sure is that many people engaged in activism of one sort or another have no compunctions about lying and flat out making stuff up, and many people accept numbers quoted as if gospel. And statistics very commonly take on a life of their own, once invented.

Charles Boritz
Reply to  MarkW
August 22, 2019 2:29 pm

Bryan A, I have hit a few birds, as well as squirrels, raccoons, and deer. I’ve had a bear hit me – I slowed down to miss a black bear sow crossing ahead of me, and a cub hit my rear quarter panel; no damage other than a nose print in the road grime.

Also, I often see a wide variety of dead birds (owls mostly), opossums, foxes, and groundhogs, amongst the above mentioned victims.

All this in one state, four vehicles, and roughly 12 years of driving.

Martin C Williams
Reply to  MarkW
August 22, 2019 2:34 pm

Mark, I must agree with you although I am not sure about cats. To start with I have worked in many of the tallest buildings in Denver; have come to work in the dark of the morning and left evenings and late at night. After first hearing about bird deaths from buildings and lit windows from these buildings at night, I took the time to survey at any time I was outside these buildings to look for dead birds. This I have done now for years. I have not found any dead birds even once other than the exploded carcasses of pigeons having been hit by our local falcons.

As for car hits, I must say I am guilty of some wildlife destruction. I often drive on remote dirt roads in Wyoming, Colorado, and Kansas. I can’t say how many cowbirds I have found stuck in the grill of the truck. And, I must admit that I did take out a couple of young turkeys out of many standing on the curve in a road on a pass south of Steamboat Springs Colorado. I also admit that I have hit a few pheasants in eastern Colorado and western Kansas.

Going back to the cats, they are great hunters, having one of my friend’s cats having proudly brought a rather upset bull snake wrapped around the cats face to his back porch where we were having a few brews. However our great bird hunter was a cooper’s hawk that lived in our neighborhood here in Colorado. My wife and I being bird lovers had multiple feeders in our back yard. Consequently the hawk found the feast. It would hide in our spruce trees and would swoop down on the feeders, not caching the birds but scaring them. The small birds, mostly finches, would scramble and then inadvertently hit our picture windows. Stunned, the hawk would easily pick them off the ground. Many hundreds I would guess met their demise from our friendly and not so shy hawk.


Nicholas McGinley
Reply to  MarkW
August 23, 2019 3:11 pm

I have had cats my whole life, and have lived most of the years on a farm nursery in the middle of nowhere in central Florida.
Wildlife central.
I have worked outside every day for most of my adult life, about 34 years total of working outside at least five days a week. I have never stopped looking around and observing things, especially things like weather, birds, animals, architecture. I have spent decades living in the outskirts of the downtown of one of the largest cities in the country, Center City in Philadelphia near Rittenhouse Square, and spent a lot of time biking around, at one point(1.5 years) being a bike messenger, outside downtown and all over every minute of every work day. I have also put in way over a million miles on the road.
I have bird feeders, many of them, and scads of birds show up, dozens of types, including doves on the ground, woodpeckers and all manner of songbirds…several per minute, all day and every day, 365. Some days in migrating seasons in is almost comical how many. I can post a video on Twitter and a link. My cats sit and plan how to catch them all day sometimes. A few times one of my cats or another has caught one, but I have found that over time in any location, there are some caught after moving in by within a few years almost none, even though I have more cats since the Hurricane Gang showed up and decided to never leave during Irma. They can basically never catch one, and some of these cats are very good hunters.
They catch everything else. When they tend to get them is when one bird makes a poorly chosen place to build a nest. When the chicks get to a certain age, they are either too noisy and the cats spot the nest and climb to it, or when they are fledging they get caught on the ground. Birds learn, and they communicate. If you doubt it, check the video of the study done on the campus of a college in the northeast:

What does occasionally wipe out and/or chase away all of them every once in a while, once or twice a year it seems, is when an owl or a hawk arrives in the neighborhood, and seems to stay until there is no sign of any bird most of the time. It happens over a week or two, sometimes virtually overnight, but that is likely because I never really spend every day sitting outside for a while…only most days and only for one or a few hours. Occasionally I will spend all daylight hours outside for a few weeks here and there on major projects and tree pruning and such.
Owls and hawks can wipe out a population in an area around a bird feeder rapidly. I think they eat a bunch every day for a few days and the rest leave. Then it has to move on, as the birds are just not there anymore. Gradually they come back, and eventually it is like nothing happened.
Cats…maybe 5 in the first two years, and one or zero a year for the past 5. Last one was years ago. I know when it happens because the cat always brings it in the house, and If I do not catch it, it winds up scattered feathers and not much else from one corner of the house to another. These days I work at home and know it right away because they all follow the hunter inside to help and watch.
In fact they do this to some degree during giant moth season, grass hopper season, and of course the never ending lizard open season.
Twice I have found dead baby flying squirrels, never a grey squirrel…they are too tough and feisty and fast. One time a rabbit in my previous house…still alive. For a while Dewey had a fascination with moles, and would bring them in alive and let them go.
Tallulah used to catch black snakes, maybe four before she got poisoned by a red tailed skink and had neurological damage…she was never the same after that. And once or twice a rat or big mouse…thank God they do not bring them in very often because they always escape and hide.
At our plant nursery, we had some cats that were trained to hunt by on the farm, outside all the time but fed , Puddy was the father, Kitty was the mom (I found her in Hurricane Elena when a kitten ran out of a bush and climbed up my leg). One of those kittens was adopted my nephew (so my sister really) and taken back to the outskirts of Philly in a house overlooking Wissahickon Valley, nothing but trees from her yard to the creek and back up the other side miles away…never been developed (largest inner city park in the world, Fairmount Park). That cat, Curly Joe, was a real hunter. She would bring wildlife of every description home to Connie and give it to her for breakfast in bed…often still alive.
It was almost a daily thing for years until they moved the cat door to another sliding door outside the bedroom.
Even she very rarely caught a bird. They are just not easy to catch, although there are a lot of songbirds. Everywhere I have lived there are. Put up a bird feeder, and within a day usually birds will be there eating the food. Where I live now is incredible. I have never seen so much wildlife. I saw a bear once, dead beside SR 82 on the way to work a few years back. Big as a large overstuffed sofa. Police and several people standing there, big dead brown bear…a giant.
I saw a dead panther on the side of I-75 a mile north of Daniels Parkway about 6 months after that. That was tying up traffic. Both were in the local news. I checked.
I have raccoons (if anyone has ever heard raccoons in the trees outside your house in mating season…let me tell you, I thought it was aliens attacking our planet), red foxes, saw Bobcats when I was installing equipment in the wetlands when they had just built Fenway South on Daniels right near Fort Myers International airport, two of them on the infield, just standing there, early that morning ( April 2012 I think), spoke to people who have seen panthers in my neighborhood, and bears (In a place called Habitat CDD. Bear broke through the screen of his pool cage, came into his pool patio, opened the trash, started to run when he yelled at it, stopped and came back and took the trash can, and opened it up and ate the chicken bones he had thrown away a day before…it smelled them ). I saw what must have been a coyote last Fall, armadillos, and all manner of small stuff.
I pay attention when I am outside.
And I know malarkey when I hear it.

Nicholas McGinley
Reply to  Bryan A
August 22, 2019 12:18 am

The number of cats in the US is tremendously exaggerated and are based on a few surveys, none of which are scientific whatsoever.
The census bureau is a good place to start debunking.
They report that on average, 48% of households have a pet.
This includes dogs and cats and fish and everything else.
117 million households, so no more than 56 million homes with pets.
This is an upper limit based on census data.
Most pets are not cats.
Dogs outnumber cats, and a lot of pets are fish and other critters
Using census data, there are no more than 60 million homes with one or more of any pet.

ASPCA and APPA estimated by self reporting survey, not scientific:
They estimate 85 million cats, but this is impossible by several lines of evidence:
First, max estimate of homes with cats is 35%, which means 40 million homes have cat or cats. Max. But this is high because it assumes all non pet owners respond to surveys in the same proportion as pet owners
Also too high because they assume 105 million homes have pets. This would be nearly 90% of households, which is almost twice the number from census data, and their own stat is 35% have cats.
So we come back to 40 million homes with cats, max.

Number acquired per year times average lifespan is another way to estimate:
ASPCA reports about
5 million cats are acquired per year, approximately. Average lifespan is 7 years for cats that spend time outside, and 14 for cats that never do. Avg is perhaps 12 years, 5 million times 12 is 60 million. Max.
But many pets are not kept until they die.
Every year, 6% of cats are rehomed (gotten rid of) by owners. So in 12 years that means 72% of cats are gotten rid of. This if true chops the 60 million down drastically.
Shelters take in 3.2 million cats per year, and only 90,000 cats are returned to owners.
All of this makes it very complicated to estimate, and random surveys are not reliable. Few have been done, and the number correlate very poorly with each other.

Dogs ownership is self reported at 44% of households
Cats self reported at 35% of households.
But people with no pets likely never respond, although the surveys assume the numbers of returns mirror the statistics overall.
So the number is very surely less than 35% based on these estimates.

Sales of cat food are known to a high degree of surety.
Also it can be estimated how many calories a cat needs to live, and what is the average cost per calorie.
Also there are surveys of how much pet owners spend per pet for dogs and cats, and people know how much they spend. This correlates well with estimates based on calories required to survive, but it is not known how much of the total spent is on treats, and how much is thrown away uneaten. It is a lot of it, but beyond that, uncertain.
Avg cost per cat per year for food is $287, about 78 cents per day, $0.78.
Total spent on cat food is $3.8 billion for dry, and another $2.2 billion for wet food.
$6 billion per year / $287/cat/year gives just under 21 million cats. If no food is wasted and several other assumptions. For there to be 40 million cats, people would have to be underestimating cost per cat by factor of two, and spending just 39 cents a day on cat food.

Average price per calorie for cat food is a narrow band, discussed in detail here:

It comes to about 7-10 calories per penny for average priced dry food, and about 2 calories per penny for premium dry, and 7 calories per cent for average wet food and 1 calorie per cent for premium wet. A cat needs (according to pet food makers) between 180 and 360 calories per day depending on body weight. That is for a range of body weights from 5 to 15 pounds. Most cats are upwards of 10 pounds when adults. My experience is that they tend to eat less than this, but that may depend on time of year. Using a median number of 270 calories/day and half of calories from dry and half from wet and 1/8 of food bought being the more expensive tier (from industry data here: https://www.statista.com/topics/1369/pet-food/), we get roughly an average of about 6 calories per cent spent on food, gives $0.45 per day.
But treats are about 1/5 of the pet food market, and not counted in those numbers.
They cost several times more per calorie than regular food, and are about as calorie dense per ounce as dry food. So that gives about $0.55 cents per cat per day.
This is conservative estimate, and assumes no waste, but most owners find a lot of food is discarded…cats are finicky, notoriously so.
So generally, the calorie per day times cost per calorie winds up lowering the cost per cat per day. And a lot of people spend for super premium, and toss away any food not eaten right away. Many people spoil the hell out of pets and do not mind doing it.
So $0.78/day is not unreasonable, and the number is no less than half that, no matter what, because that is what it takes to keep them alive.
Bottom line: Census data and food sales data and how much it costs to keep a cat fed all point to far less, no more than half as many, as the inflated ASPCA numbers. Which are not even consistent with their won estimates.
In truth, there are likely between 22 and 40 million cats in the US homes that have them.
Probably closer to 22 million. 40 million is an unrealistic upper limit by several methods of figuring it.

Stray and feral cats are similarly overestimated.

As usual, people with an agenda makes estimates of statistics that make no sense and are not even internally consistent, and are routinely exaggerated above the inflated overestimates.

It doesn't add up...
Reply to  Nicholas McGinley
August 22, 2019 8:38 am

Well, you have a lot of unsupported statistics there. How do you know that 6% of cats are re-homed if you don’t know the cat population? What is the average number of cats in households that have them? Are cats only ever fed cat food? Etc.

Reply to  Nicholas McGinley
August 22, 2019 8:38 am

One point to add. Most urban and suburban cats are strictly indoor pets….

Nicholas McGinley
Reply to  Nicholas McGinley
August 22, 2019 2:13 pm

I expressed plenty of uncertainty. If you want sources for all of the information, yo could just ask.
I started to add links, but this info is readily available with simple keyword searches.
in fact all of the info from most of the sources is unsupported, but it is reasonable to suppose that some is more accurate than other bits.
Food sold for example, is based on data from public corporations that make, ship and sell food.
This information is gathered by governments and wall street people.
Census data is the subject of an entire federal department, and is not based on one or another random survey, but built up over time from many comprehensive, (by law) surveys.
My starting place was the knowledge that many of the numbers reported by apologists are simply made up: Tracking backward to the sources, it is obvious that it is the case, as at some point you come across the original quoted source.
Sure some people have cats that eat considerable non cat food.
But how much, and how many people?
Most people live in houses or apartments, most people live in cities, most people obtain basically all food consumed from one of several types of retailers.
Having lived for a bunch of decades, many of them as an adult, and all of them with many pets and people who have pets as friends, relatives, and associates, there are certain things we know to be true from experience.
There are no hidden cat cities.
Cats are hungry little beasts with a high metabolic rate, and only eaat certain sorts of foods.
Which part do you have doubts about?

Reply to  Bryan A
August 22, 2019 8:39 pm

That flawed in many ways, some of which are explained in other comments.
We don’t know how many birds of prey are being killed. We know that from a US Court case.
U.S. to give 30-year wind farm permits; thousands of eagle deaths seen

(Reuters) – Wind farms will be granted 30-year U.S. government permits that could allow for thousands of accidental eagle deaths due to collisions with company turbines, towers and electrical wires, U.S. wildlife managers said on Wednesday…
…In 2013, the agency approved a similar plan extending “eagle-take” permits to 30 years, but a U.S. judge overturned it last year. The judge agreed with conservation groups that the agency had failed to properly assess the impact on federally protected eagle populations.

…The revised permit requires companies to hire a third party to collect data on eagle deaths rather than consultants hired by permit holders, a change hailed by Defenders of Wildlife, a backer of the measure…

Please pay attention to the last paragraph. The Windfarm operators have been the ones counting the dead birds!
Also, monitoring has been poor as they often only check from once a week to once a month. Predators carry off the carcasses quickly or, the birds of prey are wounded and fly a distance away to die.

This species of eagle is highly unlikely to survive the windmills.

Tasmanian wind farms are very efficient at killing these endangered raptors.
http://www.abc.net.au/am/content/2007/s2130927.htm …
Wind farm industry a fatal blow to eagles
JULY 27, 2019
There are less than one and a half thousand Tasmanian wedge-tailed eagles left…

Reply to  Bryan A
August 22, 2019 8:47 pm

Your argument comes, almost verbatim, from this web site.
Who they are.
This article is part of our “CleanTechnica Answer Box” collection. In this collection of articles, we respond to dozens of common anti-cleantech myths.
CleanTechnica is the #1 cleantech-focused news & analysis website in the US & the world, focusing primarily on electric cars, solar energy, wind energy, & energy storage. It is part of Important Media — a network of 20 progressive blogs working to make the world a better, greener place.
The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by, and do not necessarily represent the views of Sustainable Enterprises Media, Inc., its owners, sponsors, affiliates, or subsidiaries.
What they say.
https://cleantechnica.com/2018/02/21/wind-power-results-bird-deaths-overall/ …

…Back to other sources of bird deaths, in addition to deaths caused by domestic cats, collisions with glass in buildings is a top cause. “Bird mortality from window collisions in the US is estimated to be between 365 million to 988 million birds annually.” If we compare the top end of the researchers’ estimate for wind power bird deaths, which is 328,000 per year, with the peak from the Fish and Wildlife Service for building collisions, which is 988 million, we see that building collisions result in well over 2,000 times more bird deaths…

Now, go back up to the top where in their About Section they say this.
“The content produced by this site is for entertainment purposes only.”

Nicholas McGinley
Reply to  kctaz
August 23, 2019 2:47 am


Reply to  Willis Eschenbach
August 21, 2019 1:19 pm

I was just royally chewed out by a guy that behaves exactly like any true member of the climate cult—insults, name-calling, etc but opposes wind turbines. He simply cannot understand that wind turbines exist now only because of AGW and that by behaving like a cultist, he is damaging his argument against wind turbines and supporting the carnage.

Reply to  Willis Eschenbach
August 21, 2019 2:07 pm


Your argument is the only compelling reason I have, to countenance the building of wind turbines across the West Coast of Scotland.

No one yet, has been able to deal with the problem of the Scottish midge.

John Tillman
Reply to  HotScot
August 21, 2019 6:35 pm


I’m pretty sure that offshore wind turbines would significantly reduce midge populations.

By killing birds and bats, they might well increase the pests’ incidence.

Reply to  John Tillman
August 22, 2019 9:12 am

John Tillman

The Scottish midge can’t swim. Get in a boat, even on a loch, and within a few metres from shore you are safe.

Nor can I express here how utterly miserable one feels with no protection against them.


If nothing else, scroll down to the comment on wind turbines. 🙂

Reply to  Willis Eschenbach
August 22, 2019 10:06 am

From the German study:

Overall, the losses add up to 1200 tons per year

Reply to  Willis Eschenbach
August 23, 2019 5:43 pm

The area under the windmills is often littered with bird and bat corpses. I learned about the “it’s ok to kill a few eagles,” when I turned in a survey report noting that the power company operating the windmills (on the Altamont in fact) had “taken” a golden eagle, a bald eagle, and several smaller raptors in the small area I surveyed. It is a clear violation of the Migratory Bird Treaty Act of 1918, which also banns us mere hoi poloi from even picking up a feather from a bird covered by the treaty. Power companies with windmills or bird-frying solar generating plants have a legal “take” because of their special status as environmentally friendly companies. Thorium is the way.

Rhoda R
Reply to  Al Miller
August 21, 2019 1:52 pm

You are assuming that the CO2 warriors are truly interested the environment. We have noted, here at this site, for a number of years now, that most of the ecoactivism is driven by political agenda and if bats and endangered birds get in the way…oh well, there’s that whole omelette thing…

Reply to  Al Miller
August 22, 2019 7:32 am

To imagine you can control the weather using weather dependent energy is one of the most absurd bit of mental gymnastics I have encountered.

Reply to  Al Miller
August 22, 2019 8:03 am

well, how many bears, leopards, dogs, cats, hedgehogs, moose(meese?) and other meat eating animals are feasting on these dead birds? Is there a giant sub culture of animals around wind farms eating all this free food from the sky? there are a lot more implications here to the food chain than I can figure out, but once you start with the star gazing frogs, ya gotta go all the way down that road…..

August 21, 2019 10:32 am

Thing is, for a generator using a wind turbine to develop the torque needed to produce significant power, your primary thesis … there is large overpressure in front, and near-vacuum behind the blade is false.

No matter how fast the blade is turning, the blade pressure load can #not# be higher than a static blade sitting in the same wind slipstream. Now, if it were powered, like the blade of a propeller airplane, or the multi-blade thing visible in most turbofan engines, well … you’d be right. Its a difference of applied power, per unit fan #blade# area.

Physics of air is tough.
Glad I studied it one time Long ago on a planet Far away.


Jim Gorman
Reply to  GoatGuy
August 21, 2019 11:22 am

That would only be true for a single blade on a windmill. In essence, there are two or three other blades providing a driving force to a single blade.

John Tillman
Reply to  GoatGuy
August 21, 2019 11:24 am

Wind turbine blade aerodynamics:


Buildup of insect residue can be a problem in dry climates.

Reply to  John Tillman
August 21, 2019 3:43 pm

A fascinating link John. Thanks
Presumably in the design there is a reactive angle of attack system; but how it deals with gusts etc. —: No idea.

One of the upsides to all these bug deaths is that they produce erosion/ deposits on the blades eventually leading to the economic death of the turbine. Add this to the particulates in the air stream and you have a problem.

Many moons ago I was involved in cleaning off builtup deposits on steam turbine blades for the the CEGB ( central electricity generating board). An expensive process around £3 to £4000 per turbine back in the ‘80s and that was just our invoice. Apparently these deposits reduces the efficiency by some 10%.

John Tillman
Reply to  Alasdair
August 21, 2019 6:29 pm



That is yet again indeed experience not factored into wind turbine economic and operational calculations.

Reply to  GoatGuy
August 21, 2019 11:30 am

In a constant velocity stream certainly. With the intertia of those giant raptor ripping, Chiroptera crushing blades a brief lull in prevailing winds can affect the effective angle of attack and cause the separation suggested don’t you think?

Reply to  GoatGuy
August 21, 2019 11:30 am

And yet examination of dead bats at wind farms show lung damage by barotrauma, pressure changes.


John Tillman
Reply to  Myron
August 21, 2019 12:28 pm

No surprise, NREL used computer sims and mouse data to conclude that the pressure diferential was an order of magnitude too small to cause barotrauma in bats.


And we all know that computer games trump physical evidence in post-modern “science”.

John Tillman
Reply to  Myron
August 21, 2019 12:49 pm

Using rat data last year, the threshold was lowered ten to three to four times too low:


In the close-in zone where dangerous risk of barotrauma to lungs could occur, this paper concluded that bats would be directly struck by the blade, causing lethal blunt force trauma.

John Tillman
Reply to  John Tillman
August 21, 2019 1:16 pm

More study of the bat-rat barotrauma relationship is called for.


How about raise some lab bats, then blast them in the interest of bat survival? More animal sacrifice on the altar of renewables, aka unreliables and costlies.

Reply to  John Tillman
August 21, 2019 1:22 pm

Aren’t these the same people hawking (pun intended) wind and solar. Somehow, considering they are incapable of honesty about dead birds, I find it hard to trust their other claims. How about an independent study on a wind plant that allows unfettered entry at any time?

Nicholas McGinley
Reply to  John Tillman
August 21, 2019 2:55 pm

Pick up a bird or bat, and then pick up a rat.
Birds are not rats with wings, nor are bats.
They are light as a feather those little guys.
On the few occasions one of my cats has brought a bird into the house, I was shocked how light it was when I picked it up.
Warmista scientists are idiots.

John Tillman
Reply to  Nicholas McGinley
August 21, 2019 6:32 pm

Sheri and Nicholas,


Bats have undergone tens of millions of years of specialized evolution. NREL is part and parcel of the Climate Change Industrial Academic Complex.

Science has been thoroughly and deeply corrupted by CACA.

John Tillman
Reply to  Nicholas McGinley
August 21, 2019 6:55 pm

But they are paid to be idiots.

Reply to  GoatGuy
August 21, 2019 11:33 am

Not claiming expertise on fluid dynamics, but here’s my thinking…

#Goat#Guy is correct if thinking in terms of absolutes. But the forces driving a turbine are not going to be exerting universally consistent pressure along the many blades. In various locations along each of the blades the wind pressure will vary, at some places greater and at some places lesser than that required to push the spinning blade at its present angular velocity.

Where the pressure is lower, the pressure differential imposed by the leading edge will resemble the model of a driven propeller, only instead of being driven by a motor it is driven by the greater wind forces.

Reply to  GoatGuy
August 21, 2019 11:35 am

“… your primary thesis … there is large overpressure in front, and near-vacuum behind the blade is false.”

If the blade is cutting through air at the speed of 230 miles per hour how can there not be overpressure in the front of the blade?

Reply to  Marv
August 22, 2019 5:12 am

The blades in wind turbines are airfoils.

An airfoil traveling through the air at 230 mph produces very low pressures on the “long path” side of the blade.

These aren’t old fashioned water pumping windmills with uniform thickness blades used on amish farms still today.

Sweet Old Bob
Reply to  GoatGuy
August 21, 2019 11:47 am

Except that the wind speed at the top of the turbine can be quite different than the wind speed at the bottom …. 😉
and the blade speed will be different than either would provide if the wind speed was the same …. 😉

David Yaussy
Reply to  GoatGuy
August 21, 2019 11:55 am

That’s a question I had too. If there’s overpressure on the leading edge, and a vacuum behind, and no motive force pushing the blade into the overpressure, shouldn’t the blade be turning in the other direction?

Otherwise, another great article by Willis, who always seems to be coming up with new ideas to explore.

Nicholas McGinley
Reply to  David Yaussy
August 21, 2019 5:41 pm

The motive force is what is causing the blades to be slicing the air at 230 mph in a breeze an order of magnitude slower: Wind.
If you put a fan that is turned on outside in a breeze, blowing into the breeze, then turn off the power, what happens next?
Does the breeze keep the fan rotating the same direction it was going when powered, or does it slow, stop, and reverse direction due to being pushed by the wind?
When powered, it is pushing air from behind to in front. Or it may be regarded as grabbing air from behind and tossing it forward. Lower pressure behind, higher pressure in front. But air moves from back to front, opposite the pressure gradient, and opposite what would happen in a unpowered situation of same fan with wind blowing from the front.
When air is being pushed back the other way against an unpowered blade, it spins the other way.
Easy to check if you do not believe it.
So, more complicated but straightforward: Unpowered, the blades start out stationary and are blocking the air, which pushes on the blades because it is higher pressure in front due to being impeded. COE says this leads to lower pressure behind.
Now the blade starts moving. What happens?
In the plane of the blade rotation, is different that at the leading and trailing edges of the blade. The motion is piling up air at the leading edge of the rotation, and creating vacuum in its wake. My guess is that the blades of the fan will be moving faster than the wind at the out edge, furthest from the axis of rotation.

Reply to  David Yaussy
August 22, 2019 5:39 pm

There are some misconceptions floating around here. There is no doubt windmills kill insects, birds and bats-whether by direct contact, fluctuating pressures, or some other mechanism. Little research has been done and made public.
Nicholas McGinley’s post below is very well thought out.

A wind mill blade is an airfoiled wing. Instead of supporting a plane being pushed through the air it converts blowing wind into spinning a shaft. Trying to picture the rotating mechanical forces on the blade in your head just confuses things, at least initially. Unlike an airplane wing the blade is subject to varying forces in different directions and at different rotating speeds all along the blade.

Some interesting features about airfoils:
At any angle of attack there is a point near the leading edge where the air is not moving and the airflow separates around the blade.

Virtually all subsonic airfoils(except for some really strange cases stall-start producing more drag than lift- at around 15°AOA. all airfoils have the same basic lift curve shape and the same lift/degree change. The shape of the airfoil has only a slight effect on this angle, but it can have a big effect on whether the wing stalls abruptly with no warning or gives buffeting or even simply “mushes” and gradually starts falling, and in a plane allows an easy recovery or throws a plane into a spin.

The lift of the wing(blade) is always perpendicular to the chord of the wing(line between the leading edge and trailing edge.

When the windmill is stopped the blades are “feathered” in the position that generates no lift and minimal drag. To make power the the “angle of attack”(AOA) is increased. This is measure of the angle between the airflow and a line drawn between the leading edge and the trailing edge. The increase in angle generates lift to start the rotor spinning from the lift relative to the airflow. A windmill blade is designed to spread the work done by the flowing air evenly along the length at a certain speed and load on the shaft. Even with that twist in the blade the whole blade is never at optimum efficiency due to turbulence in the wind, defects in the blade shape, rain, snow, etc. But the blades have to be trimmed for maximum aerodynamic efficiency at an rpm to match the current load on the shaft.

Some interesting features about airfoils:
At any angle of attack there is a point near the leading edge where the air is not moving and the airflow separates around the blade.

Virtually all subsonic airfoils(except for some really strange cases) stall, or start producing more drag than lift at around 15°AOA. The shape of the airfoil has only a slight effect on this angle, but it can have a big effect on whether the wing stalls abruptly with no warning or gives buffeting or even simply “mushes” and gradually starts falling, and in a plane allows an easy recovery or throws a plane into a spin.

The lift of the wing(blade) is always perpendicular to the chord of the wing(line between the leading edge and trailing edge.

Rich Lambert
Reply to  Willis Eschenbach
August 21, 2019 1:56 pm

Willis, 8/21 10:32 AM
Another factor to consider is the distance in advance of the leading edge the blade that the overpressures extend. I would guess, not very far. Regards

John in Oz
Reply to  Willis Eschenbach
August 21, 2019 3:45 pm

The fauna don’t give a toss about our thoughts on this

Nicholas McGinley
Reply to  Willis Eschenbach
August 21, 2019 3:54 pm

The real question of course is, do bats found on the ground show that they have not been killed by being smooshed by the blade, but by some internal injury consistent with a large sudden change in air pressure.
These things are incredibly highly specialized for flight…they are not like rats at all.
Smaller bats having a wing span of 8″ or so weigh a ounce or two.
The largest bats have a wingspan of 5′ or 6′ and yet weigh at most about a kilogram (2.2 pounds).
Bumblebee bats have a wingspan of six inches and weigh 0.07 ounces!
Goldfinches weigh about half an ounce (14 grams) and have a wingspan of 8 to 10 inches!
A tufted titmouse (no joke there that I can think of) weighs as much as four nickels, 0.7 ounces, or about 20 grams or so, and has a wingspan of 9 to 11 inches…nearly a foot!
A cardinal?
42 to 48 grams, a little under two ounces. Wingspan about a foot, and 8 to 9 inches in length.

Blue jays, grackles and mourning doves tip the scale at a hefty 4 ounces, and have wingspans of
13 inches to a foot and a half, 14″-18.1″ , and 15 to 18 inches, respectively.
All are about a foot in length or less, 9″-13″ commonly.
Those are among the largest of the songbirds, and weigh four ounces.

A rat? 9″ to11″ long, plus a tail of about 7 to 9 inches, overall 16 to 20 inches. They can weigh in at two pounds.
Brown rats in the wild are smaller, 11 inches of body and 9″ of tail, but not as wide as a Norway rat found in big cities in the NE US. Brown rats weigh five to 18 ounces. Commonly, but large ones can be easily two pounds or more, as noted. 900 to 1000 grams, 32 to 35 ounces.
IOW, as much as 10 to 30 and in some cases 100 times more than a bat or a songbird.
A small rat far outweighs a very large songbird and is far smaller. Bats vary from tiny bumble bee bats to large flying foxes, but they are all very light for their size.
Think of it…the largest bat, the flying fox, has a wingspan as wide as a the height as a large adult man, and weighs at most a little over two pounds…less than the largest rat.
But the average size bat and songbird is larger and far lighter than any rat. By an order of magnitude.
[Hawks (common ones in the US are broad winged hawks) are larger, and somewhat more dense, with an average of 32″-39″ wingspan and weigh about 9.3 to 20 ounces (265-560 grams) when full grown and a breeding adult.
Larger Ferruginous hawks have 5 foot wingspan and weigh up to 5 pounds.]

The difference in density is obvious. Plus although feathers are very light, they make up a lot of the weight of a bird, as do the large wings of bats, although they are incredibly light for their size.
The tail of a rat is long and thin, but probably weighs as much as a small bird or bat.

What it comes down to is, using rats to test how birds and bats will stand up to trauma is not science, it is biological illiteracy.
Why is it that every claim by these people is a lie or just plain wrong?
And they call themselves scientists!
And get paid for these shameless and self serving lies?
This makes me angry.
I only had to think about it for a second and look it up for ten minutes to know this study is full of crap!
You can stomp on a rat and not kill it.
A large rat can squeeze under a tiny gap under a door.
A small rat can squeeze through a hole 1/4 of an inch in diameter!
The size of a ball point pen viewed longwise. As can the largest house mouse (4″ long and 45 grams average)
The largest Norway rats can fit through a hole the size of a quarter, somehow.
I inch square metal mesh is easily passable by the largest big fat rat.
They are practically made of rubber and are tough little survivors.
Try shoving a bird through a hole as big as a pen.
They are very delicate compared to rodents, and larger, meaning far less dense.
Their bones are hollow. I can scarcely imagine how delicate their little lungs are.

Reply to  Nicholas McGinley
August 21, 2019 5:37 pm

I’m severely tempted to post the Monty Python “European vs African Swallow” routine. But I won’t

Crispin in Waterloo
Reply to  GoatGuy
August 21, 2019 12:09 pm


You remind me of the guys who say that an aircraft is held in the air by the low pressure on the upper surface of the wings created by the velocity of the air over the upper and lower sides.

The pressure on the wind ward and lee ward sides is a function of the blade density and air velocity. Because you learned some physics you will know what I mean by blade density. The maximum tip speed is a function of the blade density and the air speed. Based on Willis’ numbers, what’s the blade density?

What do you suppose happens in terms of pressure change at the blade as it passes in front the tower? Is the high-low pressure change greater or lesser in front of the tower? And by how much?

Suppose I used an NC1001 blade profile and point it straight into the wind, and it moves forward into the wind due to the high pressure generated on the back of the blade overcoming the resistance generated by the front cross section. Does this higher pressure on the lee side of the blade give you pause to consider the possibility that your description above is in error, or is in error under most circumstances?

R Taylor
Reply to  GoatGuy
August 21, 2019 12:17 pm

GoatGuy, “false” is an absolute yet you apply it to the relative terms of “large” and “near”. Where does Willis say the overpressure and underpressure of a turning blade are higher than that of a static blade?

The pressure differential is there, or else the blade wouldn’t turn.

Even though most of the time these modern monuments of moronity are, indeed, kept from turning, it seems probable that the combined slicing of a turning blade and its pressure differential are more hazardous to bugs, bats and birds.

Bernie Hutchins
Reply to  GoatGuy
August 21, 2019 12:49 pm

Goat Guy – Please clarify.

What does “front” and “behind” mean here?

Are we talking speeds/pressures perpendicular to the plane of rotation (velocities parallel to wind direction as the array of blades faces, presumably, into the wind); or are we talking about speeds/pressures ahead-of or behind a segment of a blade as it rotates in a circle with velocity perpendicular to the wind? Perhaps components of both? If both, are your statements the same for

Thanks – Bernie

Paul Penrose
Reply to  GoatGuy
August 21, 2019 1:33 pm

No, you are wrong. The blade is canted wrt the direction of the wind. When the wind pushes against the surface of the blade, it causes the blade to move in a perpendicular direction to the wind. The leading and trailing edges are therefore cutting though the air creating the pressure differences that Willis mentions.

Reply to  GoatGuy
August 21, 2019 1:48 pm

I think the problem is terminology, the blade is moving perpendicular to the wind, so is the “leading edge” the edge that is being struck by the wind or the edge that is leading the rotation.

There is a large overpressure on the up wind side of the blade and low pressure down wind side.

The important point is that there are large pressure changes around the blades of a wind turbine and those are lethal to many flying animals. What you call each area is irrelevant.

Nicholas McGinley
Reply to  BillP
August 21, 2019 5:42 pm

Plus plus.

Mark C
Reply to  GoatGuy
August 21, 2019 11:42 pm

That is true for the blade as a whole. But at the tip, there can be (and is) the pressure delta as described. Nearer the centre of the blade, the pressure delta is near zero but the wind is still pushing at the blade providing the power.
In fact, this “drag” of the blade tip is one of the secondary reasons wind turbines are so inefficient. The cigar-shape turbine-style generator of a hydro dam or fuel-powered (fossil or nuclear) station is much more efficient conversion of kinetic energy of a passing fluid to rotational kinetic energy. [The primary reason of course is the wind doesn’t blow 100%.]

Reply to  GoatGuy
August 22, 2019 1:19 am

No matter how fast the blade is turning, the blade pressure load can #not# be higher than a static blade sitting in the same wind slipstream. Now, if it were powered, like the blade of a propeller airplane, or the multi-blade thing visible in most turbofan engines, well … you’d be right. Its a difference of applied power, per unit fan #blade# area.

The pressure differential can be considerably higher on a rotating turbine blade than a static blade. The pressure variation is a function of the velocity of the air over the foil to the power 2. In static condition the pressure coefficient peaks at 1 on the weather side and about -1 on the lee side. The airflow is the windspeed so the pressure range at ground level is 1.2/2 x 2 x Vwind^2.

A turbine foil at maximum power will have a pressure coefficient of about 2 on the suction side and 1 on the pressure side to give a range of 3. The tip speed is typically 8 times the wind speed so the pressure range at the tip is 1.2/2 x 3 x 64 x Vwind^2. If the tip speed is 100m/s then the pressure range is 18kPa, roughly 100 times the pressure in the stalled condition.

However I have my doubts that 18kPa variation is going to kill insects or rupture lungs. It takes around 100kPa to inflate a balloon. It has been determined that humans can survive in a full vacuum for up to 90 seconds. Dogs have been tested to survive in a full vacuum for up to 90 seconds.

Nicholas McGinley
Reply to  RickWill
August 23, 2019 3:24 am

The poor things are routinely being collected from the ground with barotrauma.
Doubts can hardly outweigh physical evidence of dead animals with no outward injury signs but internal damage consistent with a sudden change in pressure.
Birds and bats are extremely light and have very low density.
They are necessarily delicate.
Humans and dogs are grounded dwelling hunters made to be strong and dense and tough.
Like rodents.
You make the same mistake in thinking as the clowns who pretend to do science by using rats as a stand in for bats in assessing how easily they can be injured.
There is a video I posted below of several bats interacting with a turbine.
In one you see it avoid the blade but fall dead from the sky as the blade passed it.
In another the blade hits the bat and it looks like a baseball player hitting a baseball.
There is no question it is happening…you can do searches for photos and videos and autopsies of bats found on these site.
The insects were counted by German scientists.
It was not done by a thought experiment, or pretending a two pound rodent is equivalent to a bat with a similar size but weighing grams.
No one even thought of this until they started collecting the dead bodies from the ground.
What makes some people think that their sophistry is more convincing than physical evidence?

August 21, 2019 10:53 am

I think you’re on to something. Maybe the need to install gian sprayers of OFF on the towers to keep the bugs away….

August 21, 2019 10:53 am

I think you’re on to something. Maybe the need to install giant sprayers of OFF on the towers to keep the bugs away….

August 21, 2019 10:54 am

Grilled insects might cause cancer in toads so the insect zappers need to be banned in California and NY out of the abundance of caution.

August 21, 2019 10:57 am

I was unaware of the bug issue. The best and simplest rejoinder to the cat objection is that cats don’t kill bald eagles.

Reply to  tim maguire
August 21, 2019 1:00 pm

re the Bug issue: perhaps(!) the way to deal with that is to look at the other side of the equation. A single bat can eat more than 600 bugs in one hour (https://www.factretriever.com/bat-facts). OK so a turbine kills a few bugs, but every time a turbine kills a bat, just think how many bugs it is saving…

Geo Rubik
August 21, 2019 10:58 am

” …my gorgeous ex-fiancée …” Still my favorite description of yours.

joe - the non climate scientist
Reply to  Geo Rubik
August 21, 2019 12:50 pm

My gorgeous ex-financee is now my wife of 36+years

Writing Observer
Reply to  joe - the non climate scientist
August 21, 2019 4:02 pm

“ex-financee”? No, forget I asked…

Tombstone Gabby
Reply to  Writing Observer
August 21, 2019 10:25 pm

Back in “ye olde days”, when radio amateurs (hams) used Morse code almost exclusively, ‘XYL’ stood for ‘ex-young lady’ – ie wife…..

Mark Broderick
Reply to  joe - the non climate scientist
August 21, 2019 4:17 pm

“financee” ?
So, you married your accountant ? : )

August 21, 2019 11:05 am

There is another aspect of the problem not mentioned. The wind turbine owners count dead birds and bats when they can find the carcass. I suspect that scavengers are also attracted to the ground around wind turbines and affect the carcass count significantly. There may not be much left when the turbine tip hits and what is left is scavenged quickly so the count is biased.

Reply to  Roger Caiazza
August 21, 2019 1:25 pm

I’ve also read they only count in a specific radius around the turbine, assuming the turbine can only throw the deceased bird so far. That may not be the case, and count result in undercounting.

Nicholas McGinley
Reply to  Sheri
August 21, 2019 4:01 pm

How far can a 200 foot long baseball bat going 230 miles and hour or more, hit a bird?
Out of the park, I would guess.
Never even thought of that.
Each turbine kills 12,000 bugs a day?
Krikey that sounds like a lot of bugs.

August 21, 2019 11:05 am

I’ve been hit with the ‘buildings kill birds too, are you suggesting we tear down all the buildings as well’ argument as well.

The difference is we don’t put skyscrapers/buildings smack in the middle of birds feeding/nesting areas on hilltops/mountainsides and the birds (like pigeons) come to the buildings, the buildings don’t come to the birds.

The other issue with wind turbines is that they proportionately kill raptors more than others so it creates issues with the ecological balance in the areas the wind turbines are built. Rodents benefit from the reduction in raptors.

Joe B
Reply to  Bill Marsh
August 21, 2019 1:38 pm

Mr. Marsh
Article in Popular Mechanics last year described a wind farm as an Apex Predator in India due to its decimation of local raptors.
Follow on effect was an explosion in the lizard population.

Nicholas McGinley
Reply to  Bill Marsh
August 21, 2019 4:11 pm

Also, buildings are stationary and easily visible.
Turbine blades sweep an area that is mostly empty space and move so fast they are likely invisible to the birds once they are up close.
Also, the stats quoted by warmistas for birds flying into buildings are just ridiculous. Sure, it happens, but they assert it happens every day to every building. I have lived in cities for decades of my life, and spent years in a downtown area outside all day long, and never once saw a dead bird lying on the ground.
Never found a dead bird outside any place I have lived, ever…not once.
And even if they did, what kind of evil logic says that if some birds fly into buildings, it does not matter how many we kill with wind turbines?
People die in car accidents, but do we just ignore it when someone drives into a person?
(Well, that guy might have been in an accident someday anyhow…tut tut!)
And keep in mind that the number of turbines now in place is a tiny fraction of what would be needed to replace FF. And for what?
Nothing. Absolutely nothing real.
A fever dream fantasy of some hypothetical future.
These are the same people that shut down entire industries if a owl might be killed.
Impoverish an entire civilization on the (wrong and disproven) theory a plentiful but deadly carnivore might go hungry sometimes?

Weylan McAnally
Reply to  Nicholas McGinley
August 27, 2019 3:09 pm

I have seen a few “suicide” birds in my day.

While attending professional school, pigeons would regularly fly into the front doors of the building. These doors were deeply recessed with a lower covering that left the area in continual shadow. Most of the birds were just stunned and eventually recovered and flew away, but about 6 of them were killed. These windows showed the reflection of the trees located adjacent to the doors.

Currently I have hummingbirds which are flying into my back windows on my patio. We have a hummingbird feeder that attracts multiple birds. There is a “bully” hummingbird that chases the interlopers away. It is fun to watch them.

Recently, the birds being chased are crashing into the windows. On Saturday two birds being chased crashed into the window almost simultaneously. Thus far two have been stunned to the point of unconsciousness, but they recovered. These windows are also deeply recessed and are in the shade up until sunset. These windows also reflect the large trees that cover my back yard.

I suspect that the birds see the reflection of the trees and mistakenly fly into the windows.

August 21, 2019 11:12 am

How can real world observations about this be made? How about night video from drones? (Normal video-taking techniques would surely be obstructed by the windfarm operators.)

I just saw (so recently that I’m kicking myself that I can’t remember where) a video report about a guy, a musician, who’s also into advanced mathmatics. He applies mathematics to video to reveal a remarkable amount of the previously unseen.

Who’s also seen this? Who can ask him for help?

Ben Vorlich
August 21, 2019 11:18 am

I wish I’d had this article 3 years ago when there was an enquiry into a plan, now approved, to build about 10 turbines nearby where I live. The best I could manage was the usual stuff about there not being enough wind here, which there isn’t it was quite breezy today but still less than 8m/s, and they kill bat’s and birds. My main point was that we’re on the migration path of European Cranes a d these are built on a ridge about 150 metres higher than the 10km the birds have flown over and then add a blade doing 300kpb a further 150 metres above the ridge then Cranes and blades are bound to meet.

BTW in my UK life the American Grey Squirrel and home grown magpies were bigger killers of young birds than cats or windows. Usually by raiding nests or killing fledglings.

Ron Long
August 21, 2019 11:20 am

Interesting addition to the gory story about wind turbine machines, Willis. The line of wind mills that I walked under, located just NE of Casper, Wyoming, was situated along a rise in the prairie, apparently to take advantage of the venturi effect speeding up winds over the rise. There was a smorgasboard of our flying friends under the four or five windmills I walked along, some would be bug-eaters and some would be vegans. The surprise was the eagles and hawks/falcons, and these birds commonly like to ride the standing wave that forms over these types of rises. I would again encourage anyone interested in the topic of windmills/birds/bats to walk along underneath several of these choppers, you will be surprised.

Reply to  Ron Long
August 21, 2019 1:28 pm

Ron—how did you get permission to walk under them? (Assuming you had permission) The area is fenced and entry is not generally allowed. (I would love to go inside and get pictures. All my photos are from outside the fence.)

I’m considering walking around under the Shirley Basin turbines (all hundreds of them) that are on public land and not mark as no trespassing. Could be enlightening.

Ron Long
Reply to  Sheri
August 21, 2019 2:12 pm

Sheri, I was President of a company that had the underlying Sage Creek insitu uranium rights and the wind turbine company refused to give us access which we were legally entitled to. So, I documented the carnage one Monday morning at first light, utilizing a long, round-about road, and went to a meeting of the management. I offered them two choices: give us access or be prepared to defend yourselves against a clear violation of the Raptors Preservation Act. They chose wisely. Sheri, you can go anywhere you want, as long as you follow the trespass laws, wear the correct protective gear for the complex, and leave if asked to by competent authority. By the way, I was also on the Technical Committee for Pegasus Gold and we worked hard in-house to prevent animal-cyanide contact, this both to comply with laws and as a matter of good conduct.

Reply to  Ron Long
August 21, 2019 3:13 pm

Thank you for the information. I have a very good telephoto lens and I am familiar with the roads, so I may check things out. After the turbines went in, I noticed a decline in raptors in the area. I was a nature photographer at the time and instead of seeing eagles weekly, I rarely saw any for a long time. The wind plant did indeed have effect.

You have a very interesting work history. My husband worked in Shirley Basin in the uranium mine (not in-situ, of course) and in oil and coal. These occupations are far more environmentally friendly than most people realize.

August 21, 2019 11:20 am

Anyone fortunate enough to visit the Air & Space Museum on the Mall has a great opportunity to see this. The Voyager aircraft which flew round the world nonstop on a single tank of gas hangs in a foyer. The leading edge is festooned with bugs from around the planet literally. The wings of the Voyager are remarkable similar to a wind turbine blade.

August 21, 2019 11:22 am

So that’s what happened to the bees.

August 21, 2019 11:22 am

Poor monarch butterflies. RIP

John in NZ
August 21, 2019 11:27 am

It’s obvious now that you point it out.

Reply to  Willis Eschenbach
August 21, 2019 1:46 pm

Please enjoy your time in the Black Rock desert. Loved your stories of that universe.

August 21, 2019 11:34 am

There is an added factor – large predators don’t try to avoid the turbine blades.

When I go flying I always keep a sharp eye out for eagles. Most birds duck out of the way if the see an aircraft roaring towards them, but eagles never try to evade.

Millions of years evolution have taught eagles they are the lords of the sky, that nothing can challenge them in the air.

Reply to  Eric Worrall
August 21, 2019 1:26 pm

Eric, if a big wedgie heading was towards my flying machine, I’d get out of IT’S way first, rather than wait to see if it was going to avoid me.

1 Lucky Texan
August 21, 2019 11:40 am

Any edible debris that makes it to the ground is likely also attracting rodents – which most predatory birds also like to prey upon.

August 21, 2019 11:44 am

Have a few ducks land in a tailings pond though…and it is International News for months!

August 21, 2019 11:48 am

I’m developing a theory of linear squirrels. It’s typical of squirrels to run around like crazy on the road and you have to be a pretty good driver to avoid hitting such a beast. I suppose the random behavior works against their typical predators but it’s highly ineffective against cars.

I think I have noticed fewer running-around-like-crazy squirrels and more squirrels that run straight across the road. Are we seeing selection of the fittest at work?

Turbine blades don’t come anywhere near the ground. Bats and birds that fly lower will avoid the blades. If my linear squirrel model is correct, it’s a possibility that we’ll see the emergence of greater numbers of low flying bats and birds. 🙂

Bryan A
Reply to  commieBob
August 21, 2019 12:41 pm

Since Squirrels are never where you wand=t them to be and always where you least expect them to be, I have found the best solution to avoid Squirrels is to purposefully steer directly towards them. They will try to jump into your presumed path which changes by steering into them. The end result is either they unexpectedly wind up jumping out of your path or you get to make road kill stew for dinner.
just hitem and don’t worry.

R Taylor
Reply to  commieBob
August 21, 2019 1:15 pm

cB, I still don’t like the idea that bats and birds should have to adapt to accommodate human vanity.

Reply to  R Taylor
August 21, 2019 1:38 pm

It’s true that we affect the environment in various ways. Freeman Dyson thinks human occupation has been wonderful for the biodiversity of England. link

Since I was born and brought up in England, I spent my formative years in a land with great beauty and a rich ecology which is almost entirely man-made. The natural ecology of England was uninterrupted and rather boring forest. Humans replaced the forest with an artificial landscape of grassland and moorland, fields and farms, with a much richer variety of plant and animal species. Quite recently, only about a thousand years ago, we introduced rabbits, a non-native species which had a profound effect on the ecology. Rabbits opened glades in the forest where flowering plants now flourish. There is no wilderness in England, and yet there is plenty of room for wild-flowers and birds and butterflies as well as a high density of humans. Perhaps that is why I am a humanist.

The greenies love to paint all human activity as evil. It just isn’t so. It may well be that human occupation on the Earth has been a net positive for the environment.

When I compare my back yard with the forests in my region, I find that my back yard is, as far as I can tell, more biodiverse than the natural landscape.

Wil Pretty
Reply to  commieBob
August 21, 2019 2:34 pm

Progresive thought takes the view that consumption of meat is injurous to the planet. Bats and eagles are meat eaters and so are evil. As are fish and birds. They will not rest until the only remaining species are bees, ducks, pandas and cows. However anything dead that is not consumed by a meat eater is consumed by bacteria. Don’t know what the plan is to deal with them.

Bird Lover
August 21, 2019 11:50 am

The cost of each dead raptor and bat should be charged to each consumer. That way they will decide that maybe coal and natural gas, isn’t so bad.

Under the Bald and golden eagle act (& amendments), “The maximum amount of a misdemeanor offense was increased $100,000 under the Criminal Fines and Improvement Act of 1987. In addition, $250,000 will be fined for an individual for a felony conviction. Respectively, $200,000 and $500,000 will be fined in case of an organization for a misdemeanor and felony conviction.[Wikiwhatcamacallit]

Bryan A
Reply to  Bird Lover
August 21, 2019 12:43 pm

Deduct the cost from their subsidy checks monthly.

Smart Rock
August 21, 2019 11:51 am

Dead and dying birds of any type are not exclusively food for raptors. They can also be food for ground-based predators like foxes, wolves, wild cats of any persuasion, even bears, etc. I’ve developed a theory that the number of dead birds reported by the wind industry is too low because many of those avian corpses are taken away by these four-footed friends in the night, so they are never counted.

It’s a truism that any predator will behave like a scavenger when the opportunity to get some free meat presents itself. I do a lot of driving across northern Ontario, and I can report that in the last 2 or 3 years it’s becoming common to see bald eagles cruising the highways looking for road kill. The ravens that used to monopolize the road-kill business are disappearing rapidly.

This observation supports the idea that any hunter will skip the hunt if there’s road kill or wind-turbine-kill handy. It also illustrates the explosion of the bald eagle population in this corner of north America. Greenies will say that it’s because of the ban on DDT. The knee jerk reaction from the conservative side of the road is – it must be due to hunting restrictions. Could there be some truth in both of these interpretations? If anyone has really studied the issue, please tell me.

Reply to  Smart Rock
August 21, 2019 1:21 pm

When you’re examining a problem it’s useful to examine the data that’s not there. Here’s an article about the behavior of small predators in the vicinity of wind turbines. The biggest deal seems to be dirt roads which are a real boon to some species, in the case of the article, Desert Tortoises. What’s the missing data? There’s no mention of a cornucopia of dead birds and bats at the base of the turbines. In other words, the windmills don’t kill enough birds and bats to make a difference in the behavior of foxes and coyotes.

Reply to  commieBob
August 22, 2019 9:20 pm

The problem with that is this.

From a lawsuit. Guess who’s been counting the dead birds?
“The revised permit requires companies to hire a third party to collect data on eagle deaths rather than consultants hired by permit holders, a change hailed by Defenders of Wildlife…”

Plus, they do not check frequently. By the time they check, the bodies have been hauled off by scavengers and predators.
As for Desert Tortoises, the solar arrays are doing a great job of helping them along the road to extinction. They are moved out for the arrays. Most do not handle the move well and die.

August 21, 2019 11:52 am

I wonder why bats, given their echolocation capabilities, wouldn’t have at least some sort of advantage in suspecting an object (i.e., a blade) was in their path? Wouldn’t these capabilities “draw” a picture of a big round object given the blades are turning fast enough? If they’re turning slowly enough, what prevents a bat from avoiding them? Is there some economy of scale with echolocation such that it all gets fuzzy for the locator? If so, why not turn away where there’s less confusion in front of you?

Any of you sound engineers available?

Reply to  sycomputing
August 21, 2019 12:14 pm

The blade is coming from above or below the bat, not from in front. They won’t see it because they’re not evolved to look out for something approaching from above at several hundred miles per hour, and their echo location doesn’t work out at the distances you’re envisioning (being generally tuned to spot objects within a few feet of the bat), so they wouldn’t see a giant wall of spinning death either.

Reply to  Archer
August 21, 2019 2:35 pm

. . . their echo location doesn’t work out at the distances you’re envisioning . . .

I see that now. That makes sense then, thanks!


Reply to  sycomputing
August 21, 2019 12:26 pm

It would not be apparent to the bat that the blade is in the bat’s path because it is not. What happens is the blade turns into the bat’s path.

Reply to  Marv
August 21, 2019 3:09 pm


Ken Irwin
Reply to  sycomputing
August 21, 2019 2:02 pm

I rather suspect the a bats echo location works against them – I think bats mistake the wingtip vortices as swirling clouds of insects – looks like lunch – at least until they get closer.

I read one study that showed 50% (ish) of all autopsied bats killed by windturbines had only barotrauma – not a mark on them – the rest suffered blunt force trauma – were struck by the blades. More than 90% of the victims exhibited barotrauma.


Reply to  Ken Irwin
August 21, 2019 3:08 pm

Interesting. Thanks for your time!

Reply to  sycomputing
August 21, 2019 3:06 pm

Most of the bats are not hit by blades. The rapidly moving blade causes a pressure drop which causes death of the the bat in its vicinity. The technical term is “pulmonary barotrauma”. In three syllables, “their lungs burst”.

Tim Gorman
Reply to  sycomputing
August 21, 2019 3:19 pm

Bats don’t have a 360deg sound picture. At a couple hundred miles per hour on the blades the bats echosounding won’t give them enough time to react to get out of the way of the blade. By the time the blade enters their “echo view picture” its too late, especially if the bat is flying forward at best speed. They can’t stop and back up instantaneously.

Reply to  sycomputing
August 21, 2019 4:43 pm

Thanks to all who have and who will continue to take their time to answer.

Michael H Anderson
August 21, 2019 11:55 am

There are very many Utube videos of this happening, here’s one (warning: if you care at all about wildlife you might find it upsetting):


You can see plainly that the bird is attracted to the turbine.

John Tillman
Reply to  Michael H Anderson
August 21, 2019 12:20 pm

Coyotes love wind turbines.

Nicholas McGinley
Reply to  Michael H Anderson
August 21, 2019 4:24 pm

Here is infra red footage of bats getting killed, two by barotrauma after they flew out of the way of the blade, one hit like a Babe Ruth home run:

Thomas E.
August 21, 2019 12:02 pm

I simply can not for the life of me understand the outright rush for governments, companies, and individuals to “destroy the environment to save it.”

I did not see it mentioned, but I would expect an increase in the number of ground based scavengers and insect eaters as well. Those would also attract birds of prey.

Reminded me of this https://wattsupwiththat.com/2018/11/06/study-wind-farms-kill-off-75-of-buzzards-hawks-and-kites-that-live-nearby/

Again, I remember my youth, in the 70’s and 80’s in Southwestern Ontario. Energy from waste plant, burning garbage plant was built in my home town of London. It was great, well, when it ran it put a lot of ash and other crap in the air. But the main topic of conversation was the 3 R’s. Reduce, Reuse, and Recycle.

Ahhhh. back in the days.

Now 30-40 years later, that plant with a few overhauls and scrubbers, mostly works, and the 401 is full of trucks transporting garbage to Michigan. I now live in Texas and am shocked at the amount of waste that hits the landfills. It is truly disgusting.

Where we once have refillable beverage bottles, we now pretty well only have single use. But I digress. My point is, *BEFORE* we try to tackle the CO2 problem, why don’t we fix the landfill issue first. With all the technology we have, from bottle washing to Thermal Depolymerization, you would think we would have that one fixed.

Oh well. Seems to me Doug from the movie “Up” has a much broader attention span than environmentalists.

Squirrel …….

Robert W Turner
August 21, 2019 12:16 pm

Time to start writing letters to congressman and the president, demanding that environmental justice is served.

August 21, 2019 12:17 pm

Interesting, first thing I thought of was the recently outcry of the monarchs disappearing.

Here’s a butterfly counterpoint from a quick web search….

Nicholas McGinley
Reply to  Rick
August 21, 2019 4:34 pm

Simplistic hogwash.
Whoever wrote this is just making stuff up, and not being very smart of logical about it.
As we know from other scientists who actually went out and measured dead insects.

August 21, 2019 12:28 pm

Dude, I can’t believe you are still harping on this. You are so far removed from any concept of reality. You are complaining about wind turbines killing 140,000 to 328,000 birds in North America each year.

Do you have any concept of total bird mortality?

In North America, total man-caused bird mortality ranges is nearly 4 BILLION BIRDS PER YEAR!!!

The no. one cause of bird mortality is windows on building. More than a billion birds per year.

No. 2 is feral cats – over half a billion birds per year.

Electric transmission lines – more than 130 million per year.

Wind turbines bird mortality rates do not even rise above the noise level, at less than 3 times ten to the minus six of the total annual bird mortality rate. You are a scientist, right? You know what those numbers mean.

USDA has done extensive research on total bird mortality due to human causes, and states that even the total of near 4 billion bird deaths each year “has no discernible impact on the stability of avian populations”.

Really, stop embarrassing yourselves.

Roger Knights
Reply to  Duane
August 21, 2019 6:33 pm

“You are complaining about wind turbines killing 140,000 to 328,000 birds in North America each year.”

And bats, which control insect populations.
A high proportion of raptors (endangered species).
Both undercounted.
Cat-carnage overcomunted.
Read the comments.

John Tillman
Reply to  Duane
August 21, 2019 6:43 pm


The actual number of birds and bats killed by turbines of death is a million at a minimum, with a disproportionate number of endangered raptors.

But it’s probably an order of magnitude more than that. Other sources of bird and bat mortality preferentially kill species capable of rapid population increase.

Reply to  John Tillman
August 22, 2019 7:15 am

Even if it were a million birds per year – a number supported or claimed by any credible avian authority in the world, since you just made it up – is still vastly below the noise level in total bird mortality .. 0.03%. “Noise level” is anything in fractions of a percent by any rational measure.

Again, USDA researched and published papers that show that even the full human caused annual bird mortality causes no discernable impacts on avian populations.

You’re embarrassing yourselves.

Not to mention, pretending to be green defenders on this one subject, when of course the anti-renewable folks are all anti-environtalism all the time. Just reading the posts and typical commentary here at WUWT is proof positive of the anti-green mindset.

So stop shedding all those silly crocodile tears over poor dead birds. Nobody believes you.

Tim Gorman
Reply to  Duane
August 21, 2019 7:05 pm

Not many eagles, hawks, falcons, and bats are killed by running into windows of buildings. Yet a *lot* of them are killed by wind turbines!

And wind turbines have a huge impact on these species regardless of what the total bird deaths might be. You’ve just used the argumentative fallacy of Lying with Statistics. The issue isn’t the total number of birds killed. It is the total number of predator birds that are killed.

Reply to  Tim Gorman
August 22, 2019 7:18 am

State your numbers? Your data sources?

Raptors ARE a subset of total avians killed by wind turbines. Whatever proportion big birds are, it is STILL virtually unmeasurable.

Every single ranking of the human-induced causes of avian mortality does not even include a line item for wind turbines because it is so tiny as to not even make the top 10 or 20 causes.

Tim Gorman
Reply to  Duane
August 22, 2019 2:04 pm

You are still lying with statistics! The issue isn’t total avian mortality. The issue is the mortality of the avian predator species. You cannot minimize the impact on these species by trying to include them with other species!

Nicholas McGinley
Reply to  Duane
August 22, 2019 2:39 pm

How about you state your data sources Duane?
In fact the people that have traditionally kept track of such things are now apologists for the windmill and solar industries.

Reply to  Duane
August 21, 2019 7:24 pm

The numbers would be more credible if the relative impact was compared.
The electrical grid has 120,000 miles of lines. If 130 million birds are being killed by electrical lines, that’s over 1000 per mile. If that were true, there would be 3 birds falling every day, per mile, of the electrical grid.
I guarantee you that this isn’t happening.
Now let’s look at cats. Let’s say there are 70 million stray cats in the US. If they’re indeed killing 500 million birds, that would be roughly 7 per cat per year. That seems believable, but we’re talking 70 million cats.
How many wind turbines are there in the US? 50,000? If they’re killing 140,000 to 328,000 birds per year, then each turbine is comparable to 1/2 to 7/8 of a cat.
As for buildings: there are maybe 120 million buildings in the US: homes, warehouses, factories and what not. If these buildings are killing a billion birds a year – each building is also equivalent to a bit more than a cat.
In fact, we should start using units of cats to measure bird mortality – actually stray cats so “scats”.
So, we’ve determined that each of the various non-wind turbine bird killers are various fractions of scats, with actual stray cats being a large number.
The buildings: we live, work and play in them. No getting around that.
The electric grid: the number is simply not credible.
The actual stray cats: zero benefit to nature or society. Agreed we should kill them all to save the birds.
Wind turbines: do we need them? Are the replaceable with less scat mortality tech? That’s the ultimate question.

Nicholas McGinley
Reply to  c1ue
August 21, 2019 9:24 pm

Good approach re the power lines.
I first realized it must be bullshit the second I heard it and did some quick mental math. Then I checked. I know a lot of people who are linemen and who work in various industries associated with the power grid. Everyone I spoke to said the same thing…they have never seen a bird cause a short, and they would see it because it would have to be removed, it would sound like an explosion, and it would necessarily cause an outage.
In fact, it was pointed out to me and is easily confirmable that yes…power lines and distribution networks are carefully designed to make it very unlikely any sort of small animal could cause a short, and it takes a short to do any harm at all. Power lines overhead are uninsulated, except at the service entrance to a building. Birds and other animals like squirrels sit and walk on them all day, everywhere. It takes a potential difference to cause a flow of electrons, and so hot wires are never within even a foot of a ground or neutral or any path to earth that can conduct. Or else there would be arcing all over, every day, and when it rained, forget it.
The same is true of all the other numbers though.
Have you ever seen a bird hit a building? Or one lying on the ground after flying into one? Ever been in a house where a bird hit a window? Ever hit a bird with your car, or seen someone else do it, or heard someone say they hit one?
The answer to all of these for the majority of people is no or one or twice in a lifetime.
Just like the powerline bullshit which simple math can easily debunk because powerlines are not shorting out everywhere every day.
Cats were estimated based on a urban area with a dense accumulation of semiferal cats in a large city. Cats need a lot of food, and most of these feral communities of cats exist where they are being fed by people, otherwise the amount of range required for one small predatory mammal is well understood and characterized by biologists.
But what the people who made up the number of cats that are feral is, they projected out from that downtown feral community to the whole country. The US is 3.8 million square miles. There are places where thousands of people live per square mile…which is why we have 350 million people…a few densely packed urban areas. But these people calculated some 50 to 75 million feral cats! There are entire states where a feral cat would never survive even one year, even if it did not freeze to death…they are not adapted. But every square miles of mountains, rivers, lakes, prairie, corn fields, forests, Alaska, Texas, the deserts…every square mile has 25 feral cats, each catching birds every month. Even where there are no birds. A hidden army of ninja bird assassin cats, hiding behind every bush, unseen except for the occasional glimpse of one every now and then, and never in entire wide areas.
Even in Florida, with wildlife and insects and birds everywhere, there are feral cats sure, but few, and it is hard for them to survive, and they are not living on birds. Not one actual observational study has ever been done that characterized such numbers or such behavior. Not even with 350 million smart phone carrying you tubers on the lookout for anything noteworthy. open land has few cats. Even the feral ones live in close association with people in large population centers.

There is no New York City of feral cats. large areas have few or none, and some places have a few. Only cities can support several per square mile.

But when you find out where the numbers come from, it is just like most other warmista bullshit: made up. Nonsensical. Impossible. And endlessly repeated as if factual.
I have done the math and it took me a day to debunk beyond all doubt that every one of those numbers for cats, buildings, power lines, and cars are impossible, then looked up where the numbers came from, and found out they were all just made up one day, never confirmed, never even made a single observation…just a ridiculous projection.
Ever since, the numbers have been endlessly repeated as fact, exaggerated as time went by, and latched onto by some people as if they are incontrovertible.
It is literally made up from thin air to take attention away from what is an obvious and horrific ecological catastrophe in plain sight.
Being done wittingly and swept under the rug deliberately.

Nicholas McGinley
Reply to  c1ue
August 21, 2019 9:33 pm

Trust me, there are no 70,000 wild cats in the US.
That would be 20 per square mile.
One for every 22 acres
On every acre of mountain, desert, prairie, forest (it takes miles of forest to support one predator), lake, river, grain field, road and bridge.
Since obviously huge areas are impossible for even a single cat to survive long (they would be prey in most places) the numbers for where they cat find a steady supply of meals would have to be several times that. There are feral cats in large numbers only in dense urban areas where people feed them. Otherwise a few here and there.
Even the number of house cats is exaggerated, wildly, as can be proven by just checking on pet food sales.

Nicholas McGinley
Reply to  Nicholas McGinley
August 22, 2019 12:24 am

Sorry, top number should be 70,000,000.
That is the estimates by the people making up fake numbers of feral cats.

Nicholas McGinley
Reply to  Duane
August 21, 2019 8:39 pm

Because the numbers for cats and buildings are made up nonsense, not “research”.
You are embarrassing yourself by accepting the made up lies of people hired to be apologists for a corrupt industry.
Everything about the numbers for cats is made up…the number of cats, the number of birds they kill, all of it.
Made up from thin air by making ridiculous off the cuff projections.
The numbers for buildings are even worse…the logic goes from “sometimes a bird flies into a building” to “every building is hit by multiple birds every year”. Literally, that is the extent of the “research”.
If you do the math on the transmission lines, it is obvious that is bullshit too.
There are 3141 counties in the US. So just dividing those numbers up evenly, it comes to an assertion that every day in every single county in the country, 131 birds die from nesting in transformers of some such. For one thing, birds can sit on power lines and not be harmed…everyone can see it every day.
To be killed, they have to create an arc to ground. Because a direct short to ground will necessary trip the nearest breaker on a distribution line, this would require a service call to find the bird and remove it and reset the breaker.
I have a very good idea of how often something like this happens…very rarely. Most birds are far too small to contact a ground and a hot line simultaneously.
For safety and maintenance reasons, the entire power distribution network is carefully designed to make sure this rarely happens…but to believe these numbers, you have to think it happens literally everywhere, every day!
I was able to debunk this the first time I heard it within less than a day using actual information.
Look for the original source of this info…and you will find it is all made up.
The number for cars are simply estimates too. The same math shows that every driver in the US would have to be killing a bird or two every year. Everyone in the country who drives killing more than a bird a year.
I have never hit a bird.
I hit a dog once that was sitting next to a state road and walking into the road 5″ in front of me going 45mph. Doggy suicide.
And almost no one I have ever talked to has ever hit a bird, or seen one hit.
Birds are a small fraction of road kill. It is mostly ground animals and mostly at night.
4 billion has no impact because it is a fake number, top to bottom…pure propaganda, and anyone who thinks for a minute and does some math can quickly realize it must be BS.
Besides for all of that, birds that fly into buildings are thought to usually be sick or in some other way unfit.
Birds caught by cats are not very common for the vast majority of cats, and the ones they catch are babies, or sick, or old. Those are the ones predators catch. Birds are alert, and fast. They do not come out at night, when cats have their big advantage. And they are smart and learn to avoid predators, and to watch for them.
And they are all small songbirds, which breed faster than rabbits. A songbird lays a clutch of 6 to 12 or more eggs several times a year, and for numbers to stay the same, exactly one has to survive to breeding age over the lifetime of every bird, two per pair. Songbirds can live for many years.
But the ones killed by turbines are large birds, migratory birds, birds of prey, and bats.
These birds have one or two young once a year, for the most part, and many are small in number to begin with.
Bats have few predators, living in hidden colonies, never coming near the ground for the most part and most bats, over the entire life. And they are far more important ecologically than most people realize.
Many of them only eat insects, and they eat a lot of them.
Likewise, just as the numbers for buildings and cats and electric lines are fake as hell, so are the ones for turbines.
You can go and find dead birds near turbines any time you go look.
Try going around to find the birds dead in power lines, on sidewalks, on car windshields, and in Fluffy’s jaws.
You are really a jackass sometimes.

Bill Toland
Reply to  Duane
August 22, 2019 1:21 am

Spanish wind farms kill between 6 and 18 million birds a year. The USA has twice as many windfarms as Spain. You do the math.


Nicholas McGinley
Reply to  Bill Toland
August 22, 2019 2:42 pm

The US likely has many more birds as well, to be killed.
Spain is largely a desert to semi-desert.

Jim Gorman
Reply to  Duane
August 23, 2019 6:50 am

First, your numbers are based upon urban areas. The number of birds killed by windows on the Great Plains just don’t exist in the quantity you claim.

Second, your numbers of birds clearly are weighted toward urban types of birds such as song birds, thrushes, etc.

Third, the important part of the equation is the percentage of each population type of bird that is killed and their replacement rate. For example, blue birds have six to seven hatchlings twice a year. So each pair produces 12 new birds per year. Large raptors seldom have over two eggs once per year. I’ll leave it up to you to decide which species suffers most from predation by windmills.

Fourth, your numbers killed by windows is based upon birds in urban areas. There are few if any windmills and few if any large raptors in those locations so trying to compare them is like comparing apples to oranges.

Lastly, your numbers of cats has already been shown to be hogwash. Let me assure you that feral cats don’t live long in rural areas. Most people think farmers shoot them but that is not the case. Predation and starvation kills them. Make a list of predators to cats and you’ll be surprised. Foxes, coyotes, feral dogs, bobcats, snakes, and other cats make their lifespans pretty short.

Nicholas McGinley
Reply to  Jim Gorman
August 23, 2019 3:57 pm

The hogwash about numbers of cats was easy to track to it’s source.
It was one group who counted feral cats in an urban area with a colony of cats (they are only semi-feral…if you catch one while a kitten it will become domesticated to humans). So some people counted cats in this small urban area with a known huge number of cats living in an outdoor colony. It is known they only survive because a large number of people make a hobby of feeding them, every day. This is also well documented, but those people will not stop feeding them. They catch spay/neuter and release when they can, but it is difficult.
Then…and this is the incredible part…they projected the number they counted per square mile to the entire country! 20 per square mile they found in a inner city colony, times the 3.8 million square miles in the US (which includes mountains and water and empty fields and deserts and Alaska …).
And that is where it comes from.
And people like Duane, who is mostly a skeptic and claims to be knowledgeable, not only takes it for factual but insults people while repeating this nonsense.
So it is hardly surprising that people who have never calculated anything, or had an original skeptical thought, just buy it as fact.
And came to

Patrick Hrushowy
August 21, 2019 12:46 pm

The slaughter is further evidence of the consequences of the stampede of stupids.

Bernie Hutchins
August 21, 2019 12:50 pm

Goat Guy – Please clarify.

What does “front” and “behind” mean here?

Are we talking speeds/pressures perpendicular to the plane of rotation (velocities parallel to wind direction as the array of blades faces, presumably, into the wind); or are we talking about speeds/pressures ahead-of or behind a segment of a blade as it rotates in a circle with velocity perpendicular to the wind? Perhaps components of both? If both, are your statements the same for

Thanks – Bernie

August 21, 2019 1:02 pm

Saying that “cats and tall buildings kill lots of birds too” is similar to what parents may hear from little Johnny: “But Tommy’s mom lets him do it!!”. When children try to justify evil by referring to other evil, it’s immaturity. When adults do it, it’s pure evil.

August 21, 2019 1:12 pm

A few days ago I saw an unfamiliar talking head state, with the utmost certainty, that a mere .1 percent of human-caused bird deaths are due to wind turbines. The statement smelled fishy, so I did a brief search and found this article.

The link to the source of the similar claim in the article does not work. The article makes the usual excuses: We don’t kill as much as x, y or z, as if those are legitimate excuses for killing.

Hans Erren
August 21, 2019 1:28 pm

There is a decline of bees in Europe….

Writing Observer
Reply to  Hans Erren
August 21, 2019 4:05 pm

There is an increase of “organic” farming in Europe…

August 21, 2019 1:34 pm

While it’s an interesting theory, I believe the fact that the turbines are placed in the flyways of these birds has more to do with the deaths. The Casper wind plant is directly north of the North Platte river, where the eagles hunt. The eagles can easily be hit while simply flying to their hunting grounds. It was rumored turbines are put in the flyways of the endangered condors.

As for bats, the turbines are in their flight areas too—next to a river and thousands of bugs. Placement seems the most important factor, plus the number of turbines in the grouping. The 1000 turbine disaster going in on the no longer historic Overland Ranch should do a fine job of killing hundreds of raptors and other birds.

August 21, 2019 1:35 pm

Drat—I used the dread “k” word again…..

Stephen Skinner
August 21, 2019 1:44 pm

The Royal Society for the Protection of Birds (RSPB) has a section on its website ‘Climate Change’. It has a picture of wind turbines and these words: “Climate change is the greatest long-term threat to wildlife and humans.”

August 21, 2019 1:48 pm

Ya know, why doesn’t some environmentally responsible organization sue the Go’ment to stop the waivers that allow the wind turbines to kill endangered and protected species? Hel, they do it all the time to stop other things, like pipelines… Reinstating the legally required fines would go a LOOONG WAAAY to stopping all this BS.

Nicholas McGinley
Reply to  Yooper
August 23, 2019 4:26 pm

I was reading about this recently.
The reason is because the large organizations that have for many years been the ones to do these things, have been bought off or are part and parcel of the whole warmista mafia.
Sierra Club, National Audubon Society, National Wildlife Foundation (or is it fund?)…and the rest, they are all 100% down with the global warming alarum plan, hook line, and sinker.
It is shocking.
The reason is the same as the reason for the major scientific groups doing the same: They are controlled by a small core of people who are political in nature, not true conservationists or scientists anymore.
They are not in the least bit skeptical of these widely quoted numbers we see on this thread…few kills by turbines, many by other things like cats and buildings, and they are also on board with the entire “climate change” alarmist narrative.
In the old days, they would send people to stand by turbines and count, and get their own information.
But they just accept the numbers given by the apologists hired by the turbine operators.
Just like everything else involving hundreds of billions of dollars…too many people in positions to call out what is happening are instead part of the racket.


Nicholas McGinley
Reply to  Nicholas McGinley
August 23, 2019 4:29 pm

They also accept without question the idea that these turbines are preventing global warming, which is of course for anyone allowed to attend their parties the only thing that really matters.
Even questioning one small part of any of it and you are branded a heretic and out of the club.
How can it be they ignore the facts which are plain as day for us here?

August 21, 2019 1:52 pm

The Eagle has landed in aerie

on top of a windmill – that’s scary.

Doesn’t know she will die,

whacked right out of the sky

from rotating blades unawary.

The allowable yearly limit for killing bald eagles by wind turbines was upped from 1100 to 4200 on Jan 17 2017, still under the Obama administration. The allowable limit for golden eagles is still 0. If the bird-kill exceeds the allowance, heavy fines are imposed, but that is just the price of producing clean energy. in 2013 Duke energy paid a 1.9 million dollar fine for killing 14 golden eagles and 149 other protected birds.
The whole article: https://lenbilen.com/2019/04/12/what-is-more-precious-babies-eagles-or-fighting-climate-change/

Nick Werner
August 21, 2019 2:02 pm

Whenever I hear someone defend wind turbines because cats and buildings kill birds too, or hear of wind farms being exempted from the substantial fines levied against other industries when birds are killed, I am reminded of the government-appointed assassin in the movie ‘Serenity’, calmly explaining to his victim:

“This is a good death. There’s no shame in this […] We’re making a better world.”

Len Werner
Reply to  Nick Werner
August 21, 2019 6:49 pm

Hey–you want MY list of who that could apply to??

Reply to  Nick Werner
August 22, 2019 5:11 am

Well, they BELIEVE. Terrifying.

August 21, 2019 2:37 pm

There are a lot of bugs in the sky. This is a glider wing, after a four hour flight, covered in bugs.

comment image

And it can get so bad you need one of these – a de-bug.ger. It flies out along the wing, and is pulled back in with a thread.


But they have never fitted one to a windelec (wind turbine), so they must have some really dirty wings (blades) out there…


Nicholas McGinley
Reply to  ralfellis
August 21, 2019 4:36 pm


August 21, 2019 2:53 pm

Windmills are 18th century technology and a poor one even back then. Wind turbines require an enormous environmental footprint and basically disrupt the grid (the words of the Chinese govt after it lost its enthusiasm for all those turbines it errected). They are proving to be far more expensive than its proponents claimed. The most hilarious aspect is that wind proponents think the turbines are “advanced tech.” However, Don Quixote would feel right at home.

Peter Morris
August 21, 2019 3:02 pm

Willis you’re not going camping in the Lake that is Groomed, are you?

I have to admit I’d be very curious to read what you write about such an experience.

August 21, 2019 3:18 pm

Willis, two additional things to consider.

1 Insects struck by the blade will often stick and foul the blade reducing efficiency and require cleaning. https://www.researchgate.net/publication/11889978_Aerodynamics_-_Insects_can_halve_wind-turbine_power

2 Birds and bats struck and falling are prey for scavengers at the base. It’s well recognized in the literature that scavenging distorts counts of casualties. Years ago I read another study (haven’t been able to find it again) that discussed how these scavengers at the base of turbines could attract raptors which could cause more raptors to be sliced and diced by the turbines. A kind of synergistic predator prey relationship.

August 21, 2019 4:24 pm

Mmmm… Willis, you may be on to something here.

If: (1) wind turbines kill lots of insects, (2) Germany has had wind turbines for longer than most other countries, (3) the “smoking gun” study that, so we’re told, “proves” that humans are extinguishing insect populations was done in Germany; does that not raise an interesting hypothesis to be tested?

Is there any correlation between prevalence of wind farms in an area and insect population decreases in that area?

John Tillman
Reply to  Neil Lock
August 21, 2019 7:07 pm

While turbine blades differentially kill insects, they also kill their avian and mammalian predators.

The net could be more insects, which I have observed in my local AO, which has more bird and bat batterers per square mile than anywhere else on earth.

Gary Pearse
August 21, 2019 7:20 pm

Wow, didn’t know about the insect aspect! An added factor is suggested by a youtube of a condor that flies through the blades, seems to like the experience and continues to loop back until struck down.

I think the “worse than thought” carnage is because the expected number of deaths is calculated as no of birds passing (once) through the circle of the blades multiplied by the percentage area of the circle occupied by blade times time. Clearly multiple passes of individuals eating insects and because flying through is fun for soaring birds racks up a much bigger score than the simple calculated expectation.

August 21, 2019 8:02 pm

I haven’t read every comment above, but I wonder what the situation is with the offshore wind turbines?

August 21, 2019 8:17 pm

You can’t see it, but behind the tip of each moving blade there is powerful vortex trailing off downwind that contains damaging velocity and pressure gradients to at least one blade length away.

Christopher Chantrill
August 21, 2019 8:45 pm

Willis, you really are a national treasure.

August 21, 2019 9:09 pm

“So for example, it’s estimated that the wind farm at Altamont Pass in California not far from my home has killed 2,900 golden eagles”

So you are saying that in a state with 30 or so nesting pairs, that you have liked all of them with one wind farm? And with a population size of some 25000 in the states, that you kill 10 % with one wind farm.

I’m skeptical.

Nicholas McGinley
Reply to  Trafamadore
August 22, 2019 2:50 pm

This is a documented fact, easily searchable.
It is of course, nearly impossible to believe that it is true and has been ignored and allowed to continue, and is now being enlarged to the whole world, with a plan to cover the Earth with them.
But true it is, as is the plan and the current carnage, and that to come.

Nicholas McGinley
Reply to  Trafamadore
August 22, 2019 2:58 pm

Do some looking. A quick search will instantly show you the grim facts.
These are not rumors, but documented facts.
That site could not have been planned and placed any better to kill Golden Eagles if it was designed to do only that.

Bill Parsons
August 21, 2019 10:24 pm

So the next time I see a fox or coyote sitting patiently beneath a wind turbine, gazing expectantly up toward heaven, what am I to think?

Nicholas McGinley
Reply to  Bill Parsons
August 22, 2019 12:30 am

That for every coyote, they tell us there are 150 cats?

Tim Gorman
Reply to  Nicholas McGinley
August 22, 2019 2:09 pm

Coyotes like cats for lunch. There won’t be any cats around a wind turbine.

Nicholas Mcginley
Reply to  Tim Gorman
August 23, 2019 3:53 am

The reason is feral cats are few and far between except in urban areas.
Many farms have a cat or a few of them.
But in open country fields, prairies?
Owls, hawks and eagles prey on animals the size of a cat.
Obviously any large predator will hunt them too.
They are domesticated, and do not easily transition to life in the wilderness…at all.
Feral cats are common in cities, not too rare in suburbs, and very rare in rural areas.
They live near people for shelter and food.
Where no one feeds them they do very poorly.
But the main reason is why you do not see small animals, cats or anything else, running around like you see people in a city: It takes a certain amount of habitat to support a predator. 70,000,000 cats is over 20 per square mile.
Song birds weigh an ounce to four ounces and are mostly feathers. And they fly, are fast and alert. And are safe in their nest by sunset.
Raccoons do OK, because they will eat anything, can open trash cans and stuff, and are very adaptable. But even with them, it is obvious how much easier life is near people.
Near people, they are plentiful and fat.

August 21, 2019 11:05 pm

I personally won’t loose sleep if wind turbines wiped out a considerable amount of flying cockroaches. It is concerning that wind turbines are killing so may beneficial insects, bats and birds, though. And, yes, I know cockroaches to have a place in the ecology of the planet. But, so do viruses?

August 21, 2019 11:11 pm

Willis, I did not see anywhere in your Guest Post, “…what I said about the frogs eating the flies “before they hit the ground”? (Paragraph 17) However, I did see reference to “…a group of very large tropical toads gazing straight upwards…” (paragraph 4) Just sayin’!

Reply to  griff
August 22, 2019 10:43 am

A post and a site are two different things. Remember!

August 22, 2019 1:17 am

Way back in the early part of the 20th century an American named Jacobs invented wind generators for of grid use. He used a wooden propeller and carved it until it was perfect, he used a candle behind the blade when it did not flicker for its entire length when operating it was done. The formula he came up with for propellers is the gold standard for aircraft props.

Ken Irwin
August 22, 2019 2:00 am

Most raptors are opportunistic hunters – using energy conserving behavior (they don’t like flapping their wings much) – they soar on thermals or wind driven rising air currents from cliffs etc. or perch on some tall object to wait for a prey animal to enter their field of vision.
This very behavior puts them at greater risk from windmills and solar concentrators.

Michael S. Kelly LS, BSA Ret.
August 22, 2019 2:57 am

“I’m leaving tomorrow for a couple-week vacation in the Nevada desert…”

Going to “Storm Area 51”?

Just kidding.

Great post, and I think wholly reasonable. It’s truly deplorable that the Obama EPA would give a pass to the slaughter of birds of prey when so much as picking up an eagle feather off the ground and keeping it can get you a $5,000 fine plus jail time.

Have fun in Nevada!

August 22, 2019 3:34 am

Here’s a pic showing the vortex from a wind turbine. It is pretty intense considering how far downwind it carries. Link is to WUWT post from 2011. Real vertigo to a bat? https://wattsupwiththat.com/2011/04/28/the-wind-turbine-albedo-effect/

August 22, 2019 5:17 am
August 22, 2019 5:37 am

Deciding to attack pet cats in defense of wind turbines has become the go-to for the greens lately in their denial over the danger of wind turbines. I’ve been seeing it all over. the crazy Australians have begun actually killing stray cats because of their “impact on the environment”, and others are trying to green-shame anyone whose kitty ever gets outside, accidentally or otherwise. Watch out for your pet cat, the environmentalists are coming for it!

August 22, 2019 7:56 am

Sounds like the fishing is going to be great below the offshore windmills.

August 22, 2019 12:59 pm

Trump can stop the slaughter by reversing Obama’s executive order. It would be interesting to see the Press and Democrats calling for Trump to reinstate the slaughter.

Reply to  ferd berple
August 22, 2019 1:11 pm

might even be an interesting election issue. should we be willing to kill eagles to reduce climate change? If so, what else are we prepared to kill in the name of Climate Change? How about if we kill Polar Bears to prevent Climate Change from killing Polar Bears?

August 22, 2019 1:07 pm

No matter how fast the blade is turning, the blade pressure load can #not# be higher than a static blade sitting in the same wind slipstream.
here is an unpowered vehicle that says otherwise. 50 mph dead downwind in 20 mph of wind. static blades would not be able to do better than 20 mph.

Nicholas McGinley
Reply to  ferd berple
August 22, 2019 2:52 pm

It is amazing the things people assert, when the plain fact is that there are turbines all over the world and anyone can look at videos and do simple math to calculate the speed of the turbine tip, with only a stop watch, and knowing pi and a few simple formulas from 3rd grade geometry.

August 22, 2019 5:03 pm

And at the rate they are shutting down Nuclear Power Plants the amount of CO2 emissions in the USA is going to start increasing. As of June 18, 2019, there are now only 97 commercially operating nuclear power plants in 29 U.S. down from 104 before the war on CO2 begun. the amount of CO2 is only being reduced because of the switch from COAL to NG. Wind turbines are having no impact. More wind turbines are going to increase the number of NG plants running and not producing power.

August 22, 2019 8:55 pm

This study has the kill rate for insects even higher than this article.

German study, wind farms in Germany alone kill 1500 tons yearly, of insects, disrupting food chain
Done by:
Institute of Engineering and Thermodynamics

August 22, 2019 9:16 pm

There are thousands more miles of power lines being built from the remote areas where they are putting in wind and solar. This, too, is expanding the kill capacity of “green” energy.

Power lines killing Spain’s raptors at alarming rate

Nicholas McGinley
Reply to  KcTaz
August 23, 2019 3:59 am

In the US, years ago this problem was identified and the lines reconfigured to prevent it from happening. Where this was impractical, they found out when and how it happens, and took steps to make it not happen anymore: Spikes on the pylons and poles to prevent perching and nesting, and placing platforms higher than the power pylons for nesting sites.
Raptors will always nest on the highest available nesting site.
You see these all over in Florida.
It is because of their wingspan…they can touch two hot wires or a hot and a ground when their wings are extended.
This does not happen in the US anymore.

Nicholas McGinley
Reply to  KcTaz
August 23, 2019 4:09 am

Just do an image search and you can see the platform types in use.
If this is happening in Spain from power lines, they are far behind us. This was ended as a problem in the US many decades ago.

Platform of one variety:

Another type of platform using the power pylon or pole, and spikes to prevent roosting where the danger is:

Guard of the type that prevents small birds from shorting out equipment in substations and anywhere a problem has been seen:
comment image
Some others:
Perches and spikes:
comment image

August 23, 2019 6:33 am

Well Said! The giant spinning turbines are basically bird death traps – and often they cut through prime flying space making the carnage even worse.

August 23, 2019 10:09 am

“No matter how fast the blade is turning, the blade pressure load can #not# be higher than a static blade sitting in the same wind slipstream.”
Nope: If that was true, a wing moving at 30 mph would generate more lift that wing moving at 300 mph. The moving wing generates greater lift by generating greater pressure.

On a rotating blade, this is especially true towards the blade tip, where the 300 mph apparent wind speed at the tip generates a tip vortex that is significantly stronger than when the blade is standing still. This tip vortex on moving aircraft for example can be powerful enough to knock other aircraft out of the air.

The same thing happens on the road. Pass close by a parked semi and you will feel almost nothing. Now pass close by the same semi, but with the semi speeding by in the opposite direction at 100 mph. The semi will throw your car all over the road. The faster the semi is going, the worse the problem. In this case, the semi is duplicating the blade tip.

Nicholas McGinley
Reply to  ferd berple
August 23, 2019 4:01 pm

That wake vortex is why airports have a minimum clearance between departing and arriving planes of several minutes, because planes have crashed when this was not taken into account. It takes a few minutes for the vortex to subside to safe limits.
At the busy airports, wake vortex clearance time is a hard limit on the number of flights that can arrive and take off during the busy part of the day.

Steve Z
August 23, 2019 10:29 am

Wind turbines tend to attract predatory birds as nesting sites–for a mama hawk, why build a nest on the side of a cliff when there’s a nice flat power-box 100 feet or so up on a wind turbine with a bird’s eye view of flat ground full of prey? But wind turbines have vanes to ensure that they always face upwind, and predatory birds tend to take off upwind (for better lift, as airplanes do) through the path of the spinning blades. If the bird mis-times its jump in a strong wind, it’s bye-bye birdie.

%d bloggers like this: