Birds often slam into buildings and powerlines but some people consider wind turbines an even more egregious threat, with their enormous blades whirring overhead.
However, these kill far less birds than almost any other contributor, and the strategic placement of wind farms can make the threat even less pronounced.
Objections to wind turbines largely come from two groups: Well-meaning but misinformed bird lovers; and ill-meaning, informed fossil fuel fans who show an isolated, disingenuous interest in wildlife conservation in this one instance.
The key question is how many birds are being sliced and diced. Are we talking avian apocalypse or a much lower number that represents an infinitesimal fraction of feathered flyers we lose to buildings and power lines? Studies show it’s the latter, as wind turbines are responsible for the smallest number of bird deaths among all manmade causes.
There are about 50,000 wind turbines in the country and they cause an average of five annual bird deaths apiece, or a quarter of a million birds every year. The biggest killer of birds in the U.S. are members of the cat family, who take out a whopping 2.4 billion birds each year. Collisions with building windows cause the demise of another billion.
Crunching these numbers, we find that the percentage killed by wind turbines is so microscopic that it could be rounded down to zero.
Of the relatively few killed by turbines, the vast majority are songbirds, which are experiencing no population issues. Of greater concern are raptors since they exist in smaller numbers, have much lower reproductive rates, and have flight patterns that make them more likely to be near wind turbines.
Wind farm operators can be slapped with heavy fines when their product kills a bird, although since it’s impractical to avoid all deaths, a limited number of the unintentional kills are legally permissible. Whether out of concern for wildlife or the ledger book, wind farm operators embrace technology aimed at avoiding these fatal encounters.
For example, most California Condors are tagged so that when one approaches a wind farm, the turbine detects a radio transmission, which shuts it down.
A similar system employs skyward cameras to keep a lookout for eagles, with a shutdown procedure in place if the birds are in jeopardy. Radar, light, sound, and thermal cameras are additional allies in this ornithological protection plan.
But – cliché alert – an ounce of prevention worth a pound of cure. The best idea is to placing wind farms away from bird migration routes and condor populations, and this trend has been embraced.