Wind turbines are likely to cause the extinction of many of our large bird species, and of many smaller ones as well
The horrific reality
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“The horrific reality is that, in the United States alone, “eco-friendly” wind turbines are killing an estimated 13,000,000 to 39,000,000 birds and bats every year!” - Paul Driessen
These figures may appear to be exaggerated, but in reality what was exaggerated was the minimizing of bird and bat mortality, as Big Wind had managed to own the mortality statistics, enabling their massaging into “acceptable” levels (the 440,000 birds a year often quoted for the US). Indeed, monitoring contracts routinely signed between windfarm operators and ornithologists typically stipulate that reports to be prepared by the latter will be the property of the former. And to make the cover-up airtight, “gag clauses” prohibit hired ornithologists to disclose their findings in any way or form.
Think of it that way: if average mortality were of one bird per turbine per day (not an unreasonable hypothesis), for 39,000 turbines in the US (IEA figure for the end of 2011) this would come to 365 birds x 39,000 turbines = 14,235,000 dead birds per year for the US.
And if wind turbines killed about twice as many bats as they did birds, which is likely because 1) scientists have found that bats are attracted to wind turbines, 2) most monitoring studies come up with much higher figures for bats than birds, and 3) just watch this video where bats are struck, or “barotraumized” to death in front of your eyes:
... then, average bat mortality would be: 365 x 2 x 39,000 = 28,470,000 dead bats per year.
For birds and bats taken together: 14,235,000 + 28,470,000 = 42,705,000 killed yearly in the US.
This would be higher than the “13,000,000 to 39,000,000 birds and bats every year” from Paul Driessen’s article. So the average estimate of the Spanish Ornithological Society would come down to, in round numbers, one bat per turbine per day, and one bird every other day. Nothing surprising about that, considering that each wind turbine sweeps an airspace as large as a football field (on average), sometimes as often as once per second, with blades whose speed at the tip varies between 100 and 200 mph. And they do it at a height where a considerable number of birds fly. On top of that, bats are attracted to the blades (as per the video above), arguably by the vibrations these emit, and raptors investigate the perching opportunities:
To my knowledge, there is no statistically-proven difference between bird and bat abundance to be found in Spain, as opposed to the US or any other country for that matter. We may therefore take, as a rule of thumb, the following to be applicable to just about to every country: one bat per turbine per day, and one bird per turbine every other day. Note: this estimate includes mortality caused by the high tension lines that link each windfarm to the grid. SEO/Birdlife very conservatively calculated as follows: an average of 9 km of power lines per windfarm, and a “minimum detected mortality” of “1.07 individuals per km”. In reality, mortality caused by power lines is much higher: “Scientific studies have estimated that high tension lines kill on average 200 birds per kilometre (1). In migration zones, the toll is higher at 400-500 birds/km (2) & (3) .” This is based on three studies, the one with the highest estimate being from Birdlife International, whose partners are the most prominent bird societies in the world: Audubon, RSPB, NABU, SEO, LPO etc.:
The article’s estimate is thus shy of reality, if real mortality by power lines built because of wind farms is taken into full account.
Some will say: it is less than the birds killed by cars, cats etc. But those are mainly sparrows and song birds. Cats never kill an eagle, a swan or a crane. Wind turbines do. The truth has to be faced once and for all: wind turbines are likely to cause the extinction of many of our large bird species, and of many smaller ones as well.
Cats, cars and windows don’t kill bats; wind turbines do. The large numbers of bats they kill will accelerate their extinction: they are slow-reproducing animals, and some species of bats are already on the endangered list. The rapid decline in bat populations is likely to cause an increased use of pesticides in agriculture, with a corresponding increase in food prices and food-related allergies and illnesses.
Now, we must realise that wind turbine numbers are set to multiply over the next decades, by as much as ten times in some countries. As argued by Paul Driessen, the only way to save our biodiversity is for our elected representatives not to renew the subsidies to the wind industry.