Wind turbines worldwide are being blamed for an increase in the deaths of bats, according to an analysis led by the U.S. Geological Survey and published in Mammal Review. Collisions with wind turbines worldwide and the disease white-nose syndrome in North America lead the reported causes of mass death in bats since the onset of the 21st century, according to an announcement by the USGS. The new threats now surpass all prior known causes of bat mortality, natural or attributed to humans.
Wind farms in northwestern Oklahoma where several well-known bat caves are located are blamed for some bat deaths. Mexican free-tailed bats use the Selman Bat Cave which is in a state-run Bat Cave Wildlife Management Area. It consists of a tract of 340 acres near Woodward and wildlife officials say it contains the state’s largest maternity colonies of the Mexican free-tailed bats. The bats migrate to Oklahoma each summer. Others are located in the popular Alabaster Caverns. But scientists now fear their future and those of bats worldwide might be in doubt.
“Many of the 1,300 species of bats on Earth are already considered threatened or declining. Bats require high survival to ensure stable or growing populations,” said Tom O’Shea, a USGS emeritus research scientist and the lead author on the newly-released study. “The new trends in reported human-related mortality may not be sustainable.”
The study said that prior to the year 2,000 intentional killing by humans caused the greatest proportion of mortality events in bats across the globe. Since the dawn of the 21st century, however, collisions with wind turbines worldwide and the white-nose syndrome in North America are the primary reported causes of mass mortality in bats.
The authors found that bats across the world could benefit from policy, education and conservation actions targeting human-causes mortality.
“Determining the most important causes of bat mortality is a first step toward trrying to reduce our impact on their populations,” said David Hayman, another author of the student and a senior lecturer at Massey University in New Zealand.
