How are bats affected by wind turbines?

Dead bats are found beneath wind turbines all over the world. It’s estimated that tens to hundreds of thousands die at wind turbines each year in North America alone.

Unfortunately, it’s not yet clear why this is happening. It’s possible that wind turbines interfere with seasonal migration and mating patterns in some species of bats. More than three quarters of the bat fatalities at wind turbines are from species known as “tree bats,” which tend to migrate long distances and roost in trees. These bats migrate and mate primarily during late summer and early autumn, which is also when the vast majority of bat fatalities at wind turbines occur. It’s also possible that bats mistake slow or stopped turbine blades for trees.

Learn more at the USGS North American Bat Monitoring Program (NABat) website.

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Filter Total Items: 23
July 26, 2012

PubTalk 7/2012 — Wind Energy and Wildlife

-- the challenges of wind-energy development and wildlife conservation

by Manuela Huso, Research Statistician


  • Wind-power development in the United States is increasing exponentially, with proposals to provide 20% of the country's total power by 2030.
  • High numbers of bird and bat carcasses at some wind farms
USGS CoreCast
March 30, 2011

Beyond Billions: Threatened Bats are Worth Billions to Agriculture

Insect-eating bats provide pest-control services that save the U.S. agriculture industry over $3 billion per year, according to a study released today in the journal Science. However, scientists with the U.S. Geological Survey, University of Pretoria in South Africa, University of Tennessee, and Boston University who contributed to the study warn that these valuable

USGS CoreCast
October 20, 2009

Wind Energy: A Scare for Bats and Birds

Several USGS scientists are investigating the problem of fatal bat and bird collisions with wind turbines. USGS scientist and bat specialist Dr. Paul Cryan at the Fort Collins Science Center chats with Juliette Wilson about whether we can have our wind turbines and healthy populations of bats and birds too.

Image: Hoary Bat Victim

Hoary Bat Victim

A hoary bat (Lasiurus cinereus) found dead beneath a wind turbine, an apparent victim of a blade strike or near-contact barotrauma (lung failure from severe and abrupt pressure change; here, caused by the spinning blades). Prior to the problem of bat fatalities at wind turbines, biologists rarely encountered hoary bats.

Attribution: Ecosystems
Image: Bat with Radio Transmitter

Bat with Radio Transmitter

USGS biologist Paul Cryan releases a bat carrying a miniature radio transmitter. Researchers are increasingly turning to high-tech methods to try to learn more about the mysterious lives of bats.

Attribution: Ecosystems
Bat Colony

Bat Colony

This image shows a colony of adult southeastern myotis bats. This bat species is susceptible to the deadly bat fungal disease known as white-nose syndrome.

Image: Wind Turbine Blade

Wind Turbine Blade

This photo shows one of the three 135-ft blades of a turbine before installation. Although the blades of wind turbines appear to move quite slowly to the human eye, blade tips often move at speeds faster than 100 mph.

Attribution: Energy and Minerals
Image: Bats and Wind Energy

Bats and Wind Energy

USGS biologist Paul Cryan. Biologists hope to learn more about the scale and causes of bat fatalities at wind turbines by searching for carcasses of bats beneath turbines and carefully documenting the conditions under which they are found.

Attribution: Ecosystems
Image: Bats and Wind Energy

Bats and Wind Energy

USGS biologist Paul Cryan examines the carcass of a hoary bat (Lasiurus cinereus) found beneath a wind turbine. By examining the casualties, biologists hope to learn more about why migratory bats are so susceptible to wind turbines.

Attribution: Ecosystems