Wind Energy and Bird Mortality
A rather curious letter recently appeared in the Tulsa World Editorial page titled Wind Turbines, by Jim Wiegand, Redding, CA. Mr. Weigand has no ties to Tulsa, yet the editor published it and added a note: “Wiegand is a nationally recognized wildlife biologist and expert on the effects of wind turbines on birds.” The letter started with, “The wind industry is hiding massive turbine-related bird and bat genocide. The industry has created fraudulent mortality studies and been given voluntary guidelines in order to hide its slaughter.” The letter never mentioned birds again but went on into conspiracy theories and a criticism of wind energy.
Wind-turbines do sometimes kill birds and bats, but bird genocide? In other of his writings, Mr. Wiegand claims windmills are responsible for dozens of Whooping Crane deaths, and that wind turbines will cause their extinction within five years. So far, there is not one Whooping Crane death that can be attributed to windmills. Carla Gilbert, in a post to the article, disputed the danger to similar birds. “When I was traveling in Portugal a number of years ago we could see many wind turbine farms from the highway. We were informed that the storks like to build their nests atop them. When the bus stopped for refueling I took pictures of the storks sitting on their nests atop the turbines and saw several storks coming and going from their nests. I did not see any injured or dead birds.” And, the storks are not becoming extinct as a result of the windmills. One falconer, who was at first worried about the windmills, now puts his falcon boxes on wind turbines and does not consider them a greater threat to birds than his picture window.
There has been considerable opposition to windmills and of renewable energy in general, so it is difficult to know whether all the criticisms are factual. Studies have found about an average of five to eight dead birds per windmill. That is about the number of birds who do themselves in on a picture window each year. When you add in the birds killed by cars and by hunting, it would seem that man’s other activities are a greater threat to the birds than wind turbines. For birds, the main threats are windows, cars, climate change, disease, hunters and pesticides.
There is a concern for protected species such as lesser prairie chickens and eagles. There are severe penalties for harming eagles, so to be on the safe side, the owners’ of windmills apply for permits to legally kill eagles. That has caused quite an outcry, but recently, the government gave the companies a 30 year moratorium on enforcing protection laws, while they study the problem. It does not seem likely that an eagle would fly into a windmill, particularly since another criticism is about the noise windmills make. Still there are confirmed reports that 85 bald eagles were killed by windmills in the past five years, about 17 per year. Eagles are at the top of the food chain, so any environmental pollutant is likely to harm them, and DDT was the main cause of their population decline. Once DDT was banned and eagles became protected, their population recovered to about 140,000 in North America. They have been taken off the threatened species list. They are harmed by many pollutants associated with energy production – about 280 were killed by the Exxon Valdez oil spill. It is a shame when one of the magnificent birds is killed by accident, but if we cut out any activities that might harm them, then we would have to cease much of our energy production. **
The concern about the lesser prairie chicken is that they avoid tall structures, and windmills might cause them to move from their normal habitat. Prairie chickens gather to mate each spring in large communal areas called leks. One enterprising oil company, opposed to wind power, drove a group of reporters up to a lek in the Osage Hills. They wanted to show the reporters what might be lost if windmills were built there, as if driving a van full of reporters around their lek is not going to disturb them. Many of the problems with wildlife and noise could be addressed by where the windmills are sited, and reasonable laws are needed to see that the windmills will disturb animals and people as little as possible.
Research finds the actual evidence of bird kills by windmills to be greatly exaggerated. In the Journal of Applied Ecology Volume 49, Issue 2, pages 386–394, April 2012, the authors found the impact of wind farms on bird populations to be minimal with the greater impact being during construction than during subsequent operation. A comprehensive study of bird mortality in Canada found most human-related bird deaths (about 99%) are caused by feral and domestic cats, collisions with buildings and vehicles, and electricity transmission and distribution lines. A related peer reviewed Canadian study of bird mortality says their data suggests that less than 0.2% of the population of any bird species is currently affected by mortality or displacement by wind turbine development. They concluded that even though the number of windmills are projected to grow ten times over the next two decades, “population level impacts on bird populations are unlikely, provided that highly sensitive or rare habitats, as well as concentration areas for species at risk, are avoided.”
Mr. Wiegand’s letter is mostly fiction. A search shows that Mr. Weigand has a degree in biology from the 1970’s and makes his living by selling antiques. He has done nothing that would qualify him as an expert in wildlife biology, and none of his claims, here or elsewhere, are backed by credible research. His avocation is writing letters to newspapers and posting comments on websites critical of wind energy. Some people can’t see the value, or the beauty of windmills, and they look for any excuse to criticize them.
**Note added on 09/20/2015: Here is an estimate of the number of birds killed by each major energy source from US News and World Reports..
(c) 2014 J.C. Moore