SUMMARY:
Bird mortality by collisions with wind turbine rotor blades and turbine towers have been weaponized against the industry by critics in the fossil fuel sector and bird advocates. And bird deaths are a very good reason for opposing wind turbines, along with their high cost of electricity, long, ugly transmission lines, intermittent electric power and infrasonic noise that travels for miles! This recent Norwegian study is getting lots of publicity, so I wanted to analyze the quality of the study. It would be good news, if true
The study's findings are based on only four wind turbines, over only 3 ½ years. That makes me suspicious. It's difficult to count dead birds in the vicinity of a wind turbine. The turbine blades kill insects, fresh food that attracts birds who eat the insects. Many of the birds are killed, fresh food that attracts larger birds who eat the dead or injured small birds. Then some of the larger birds are killed, fresh food that attracts predators who eat the dead or injured large birds. It's all disgusting to me -- wind turbines and nature are disturbing! Nature makes it hard to count wind turbine birds deaths:
https://tethys.pnnl.gov/sites/default/files/publications/May_EcolEvol_2020.pdf
DETAILS:
Many birds collide with wind turbines at night, when tower and/or turbine blade colors are irrelevant. Further study is needed before we know if changes in wind turbine colors would be effective to significantly reduce bird deaths in a variety of locations.
The Norway study's success needs to be replicated elsewhere. In the Unites States, however, the color of turbine blades, which can be huge, is strictly regulated by the Federal Aviation Administration (FAA). Right now, light gray as the darkest allowable paint allowed. White and gray-colored turbines, the FAA says, have proved to be the most visible to pilots.
The study claims painting just one of a wind turbine's three blades black led to a dramatic decline in bird mortality, along the Norwegian coast. The new research shows bird deaths from turbine collisions dropped by up to 71.9% when one turbine blade was painted black, compared with unpainted turbines at the same wind farm. The study was published last month in the peer-reviewed journal Ecology and Evolution.
Bård Stokke of the Norwegian Institute for Nature Research, one of the lead authors, said the findings could address the wind industry's Achilles' heel, its impact on birds.
"Our hope is therefore that these measures, given their positive effects on birds and the fact that they are relatively simple and low cost, will be used in future wind energy developments both in Norway and abroad," he said in an email.
The study was at the Smøla wind farm, a flat marshy area along Norway's west coast. When completed in 2005, the 68-turbine wind farm was one of the largest onshore facilities in northern Europe. Over 10 years, trained dogs found nearly 500 dead birds at the base of turbines, killed by collisions with blades, or with the towers, he said. Two species were killed at high rates: Willow ptarmigan, which were colliding with the base of the turbines, and white-tailed eagles, which were flying into the blades. My instincts say that's a huge undercount of bird deaths.
The team found a 2002 University of Maryland laboratory study showing a single black blade could reduce bird impacts. So the northern European researchers began a field experiment at Smøla in 2013 using four painted turbines as their study subjects.
Researchers said birds seemed more aware of what's happening to their right and left when flying through a "perceived" open air space, like a wind farm. They watch for movement that denotes predators and prey along their laterals, and below them. The blurred motion of moving wind blades directly in front of them doesn't appear as an obstruction.
When researchers at the Norwegian Institute for Nature Research and the Lake Ånnsjön Bird Observatory in Sweden painted a single black blade out of three on a rotor, it reduced "motion smear", providing birds with a visual cue of an obstacle to evade.
The motion smear effect is known to U.S. birders, and paint variations have cropped up in studies before, said Garry George, director of the National Audubon Society's Clean Energy Initiative. But the Norwegian study has excited birders "We're very excited about this," he said, but didn't necessarily see it as a silver bullet.
The simple question posed by their study addresses a fairly complicated problem: tremendous physiological variety among birds and remaining mysteries about how they perceive the world, he said. "So many different species of birds have different ways of seeing things," he said. "We don't know what they see."
The rapidly expanding wind industry kills roughly 250,000 birds annually in the U.S., according to Fish and Wildlife Service (FWS) estimates. I suspect the real number is much higher. The American Wind Energy Association notes the FWS estimate represents only 0.01% of estimated human-caused bird death. Mortality for birds is far greater from power lines, oil wastewater pits and domestic cats. Hey, my cat stays indoors -- Mr. Sneaky never kills anything!
The wind sector is growing, reaching 7.3% of the the U.S. power capacity last year. Wind power is often (falsely) claimed to have huge environmental benefits compared with fossil fuel power. The Norwegian researchers are optimistic their collaboration with regulators, government entities and the wind industry will have a long-term positive impact on protecting birds. I have my doubts, but remain optimistic.