Title: Bats in the West: Discoveries, Questions, and Future Research
By Gabriel A. Reyes, USGS Biologist
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: North American Bat Monitoring Program (NABat)
Related
Are bats blind?
No, bats are not blind. Bats have small eyes with very sensitive vision, which helps them see in conditions we might consider pitch black. They don’t have the sharp and colorful vision humans have, but they don’t need that. Think of bat vision as similar to a dark-adapted Mr. Magoo (a cartoon character with very poor vision). Learn more at the USGS North American Bat Monitoring Program (NABat)...
Are bats dangerous?
All healthy bats try to avoid humans by taking flight and are not purposely aggressive. Most bats are about the size of a mouse and use their small teeth and weak jaws to grind up insects. You should avoid handling bats because several species, such as the hoary and big brown bats, have large teeth that can puncture skin if they are handled improperly. Less than one percent of the bat population...
What do bats eat?
Bats are the most significant predators of night-flying insects. There are at least 40 different kinds of bats in the U.S. that eat nothing but insects. A single little brown bat, which has a body no bigger than an adult human’s thumb, can eat 4 to 8 grams (the weight of about a grape or two) of insects each night. Although this may not sound like much, it adds up—the loss of the one million bats...
What should I do if I find dead or dying bats, or if I observe bats with signs of White-nose Syndrome?
If you find a dead or dying bat: Contact your state wildlife agency, file an electronic report in those states that offer this service, e-mail U.S. Fish and Wildlife Service biologists in your area or contact your nearest Fish and Wildlife Service field office to report your potential White-nose Syndrome (WNS) observations. It is important to determine the species of bat in case it is a federally...
Where do bats live?
Bats can be found in almost all parts of the world and in most regions of the United States. In general, bats seek out a variety of daytime retreats such as caves, rock crevices, old buildings, bridges, mines, and trees. Different species require different roost sites. Some species, such as the Mexican free-tailed and gray bats live in large colonies in caves. A few solitary species, such as the...
Why is it important to know the locations of wind turbines?
No publicly-available, national database of wind turbines existed prior to the creation of the USGS Windfarm mapper, which was replaced with the U.S. Wind Turbine Database (USWTDB) in 2018. Knowing the location of individual turbines and their technical specifications creates new opportunities for research and improved siting and is important information for land and resource management. In...
Why are bats important?
By eating insects, bats save U.S. agriculture billions of dollars per year in pest control. Some studies have estimated that service to be worth over 3.7 billion dollars per year, and possibly as much as 53 billion dollars per year. This value does not, however, take into account the volume of insects eaten by bats in forest ecosystems and the degree to which that benefits industries like lumber...
PubTalk 09/2019 — Bats in the West
Title: Bats in the West: Discoveries, Questions, and Future Research
By Gabriel A. Reyes, USGS Biologist
Pallid bat with transmitter
A Pallid bat (Antrozous pallidus) is outfitted with a radio transmitter to help lead us to its roost. The transmitter is attached with a temporary adhesive that will wear off within around 2 weeks, about as long as the battery life of the transmitter lasts.
A Pallid bat (Antrozous pallidus) is outfitted with a radio transmitter to help lead us to its roost. The transmitter is attached with a temporary adhesive that will wear off within around 2 weeks, about as long as the battery life of the transmitter lasts.
Bat emergence, Paul Cryan, USGS photo.
Mexican free-tailed bats that emerged from Bracken Cave in Texas fly among the trees in the early evening sky.
Mexican free-tailed bats that emerged from Bracken Cave in Texas fly among the trees in the early evening sky.
PubTalk 7/2012 — Wind Energy and Wildlife
-- the challenges of wind-energy development and wildlife conservation
by Manuela Huso, Research Statistician
-- the challenges of wind-energy development and wildlife conservation
by Manuela Huso, Research Statistician
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Related
Are bats blind?
No, bats are not blind. Bats have small eyes with very sensitive vision, which helps them see in conditions we might consider pitch black. They don’t have the sharp and colorful vision humans have, but they don’t need that. Think of bat vision as similar to a dark-adapted Mr. Magoo (a cartoon character with very poor vision). Learn more at the USGS North American Bat Monitoring Program (NABat)...
Are bats dangerous?
All healthy bats try to avoid humans by taking flight and are not purposely aggressive. Most bats are about the size of a mouse and use their small teeth and weak jaws to grind up insects. You should avoid handling bats because several species, such as the hoary and big brown bats, have large teeth that can puncture skin if they are handled improperly. Less than one percent of the bat population...
What do bats eat?
Bats are the most significant predators of night-flying insects. There are at least 40 different kinds of bats in the U.S. that eat nothing but insects. A single little brown bat, which has a body no bigger than an adult human’s thumb, can eat 4 to 8 grams (the weight of about a grape or two) of insects each night. Although this may not sound like much, it adds up—the loss of the one million bats...
What should I do if I find dead or dying bats, or if I observe bats with signs of White-nose Syndrome?
If you find a dead or dying bat: Contact your state wildlife agency, file an electronic report in those states that offer this service, e-mail U.S. Fish and Wildlife Service biologists in your area or contact your nearest Fish and Wildlife Service field office to report your potential White-nose Syndrome (WNS) observations. It is important to determine the species of bat in case it is a federally...
Where do bats live?
Bats can be found in almost all parts of the world and in most regions of the United States. In general, bats seek out a variety of daytime retreats such as caves, rock crevices, old buildings, bridges, mines, and trees. Different species require different roost sites. Some species, such as the Mexican free-tailed and gray bats live in large colonies in caves. A few solitary species, such as the...
Why is it important to know the locations of wind turbines?
No publicly-available, national database of wind turbines existed prior to the creation of the USGS Windfarm mapper, which was replaced with the U.S. Wind Turbine Database (USWTDB) in 2018. Knowing the location of individual turbines and their technical specifications creates new opportunities for research and improved siting and is important information for land and resource management. In...
Why are bats important?
By eating insects, bats save U.S. agriculture billions of dollars per year in pest control. Some studies have estimated that service to be worth over 3.7 billion dollars per year, and possibly as much as 53 billion dollars per year. This value does not, however, take into account the volume of insects eaten by bats in forest ecosystems and the degree to which that benefits industries like lumber...
PubTalk 09/2019 — Bats in the West
Title: Bats in the West: Discoveries, Questions, and Future Research
By Gabriel A. Reyes, USGS Biologist
Title: Bats in the West: Discoveries, Questions, and Future Research
By Gabriel A. Reyes, USGS Biologist
Pallid bat with transmitter
A Pallid bat (Antrozous pallidus) is outfitted with a radio transmitter to help lead us to its roost. The transmitter is attached with a temporary adhesive that will wear off within around 2 weeks, about as long as the battery life of the transmitter lasts.
A Pallid bat (Antrozous pallidus) is outfitted with a radio transmitter to help lead us to its roost. The transmitter is attached with a temporary adhesive that will wear off within around 2 weeks, about as long as the battery life of the transmitter lasts.
Bat emergence, Paul Cryan, USGS photo.
Mexican free-tailed bats that emerged from Bracken Cave in Texas fly among the trees in the early evening sky.
Mexican free-tailed bats that emerged from Bracken Cave in Texas fly among the trees in the early evening sky.
PubTalk 7/2012 — Wind Energy and Wildlife
-- the challenges of wind-energy development and wildlife conservation
by Manuela Huso, Research Statistician
-- the challenges of wind-energy development and wildlife conservation
by Manuela Huso, Research Statistician
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Updated Date: March 14, 2025