Title: Bats in the West: Discoveries, Questions, and Future Research
By Gabriel A. Reyes, USGS Biologist
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 in the Northeast has probably resulted in between 660 and 1320 metric tons of insects no longer being eaten each year by bats.
Bats locate each insect by echolocation, then they trap it with their wing or tail membranes and reach down to take the insect into their mouth. This action, as well as the chase, results in the erratic flight most people are familiar with when they observe bats feeding in the late evening or around lights at night.
Other species of bats eat many different things, including fruit, nectar, and pollen. Bats are important pollinators as they fly from plant to plant in search of food. In the southwestern deserts of North America, bats are the key pollinators of saguaro and organ pipe cactus. Tequila is made from the agave plant, which is pollinated by bats.
Learn more: North American Bat Monitoring Program (NABat)
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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...
Do vampire bats really exist?
Yes, but not in most of the United States. Of the three species of vampire bats in North America, only a single specimen has been recorded for the United States in extreme southwest Texas. Vampire bats do not suck blood--they make a small incision with their sharp front teeth and lap up the blood with their tongue. Vampire bats in Mexico and South America feed on the blood of livestock such as...
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...
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...
What species of bats are affected by White-nose Syndrome?
White-nose Syndrome mostly affects hibernating bats. More than half of the 47 bat species living in the United States and Canada hibernate to survive the winter. Twelve bat species , including two endangered species and one threatened species, have been confirmed with white-nose syndrome in North America. The causative fungus, Pseudogymnoascus destructans ( Pd ), has been found on an additional...
What is White-nose Syndrome?
White-nose syndrome is an emergent disease of hibernating bats that has spread from the northeastern to the central United States at an alarming rate. Since the winter of 2007-2008, millions of insect-eating bats in at least 40 states and eight Canadian provinces have died from this devastating disease. The disease is named for the white fungus, Pseudogymnoascus destructans , that infects skin of...
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...
Title: Bats in the West: Discoveries, Questions, and Future Research
By Gabriel A. Reyes, USGS Biologist
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.
A little brown bat (Myotis lucifugus) with white-nose syndrome hibernating in a Virginia cave during late spring of 2016.
A little brown bat (Myotis lucifugus) with white-nose syndrome hibernating in a Virginia cave during late spring of 2016.
Dissected guano pellet showing antennae, eyes, and body fragments of midges.
Dissected guano pellet showing antennae, eyes, and body fragments of midges.
Bats benefit from maintaining a close-knit roosting group because they increase reproductive success and it is important for rearing pups.
Bats benefit from maintaining a close-knit roosting group because they increase reproductive success and it is important for rearing pups.
Imagery from temperature-sensing cameras showing bats in hibernation. This new footage suggests that bats who warm up from hibernation together throughout the winter may be better at surviving white nose syndrome, a disease caused by a cold-loving fungus ravaging insect-eating bat populations in the United States and Canada.
Imagery from temperature-sensing cameras showing bats in hibernation. This new footage suggests that bats who warm up from hibernation together throughout the winter may be better at surviving white nose syndrome, a disease caused by a cold-loving fungus ravaging insect-eating bat populations in the United States and Canada.
When bats detect an insect from returned echolocation calls they rapidly increase the pulse rate and raise the frequency of calls in order to gather more information on the insect including location. These calls emitted right before a bat closes in on an insect are called terminal phase calls or "feeding buzzes".
When bats detect an insect from returned echolocation calls they rapidly increase the pulse rate and raise the frequency of calls in order to gather more information on the insect including location. These calls emitted right before a bat closes in on an insect are called terminal phase calls or "feeding buzzes".
USGS and Virginia Tech scientists captured female northern bats and fitted them with tiny radiotransmitters and numbered armbands. The bats were then released and tracked to determine what roosts they were using.
USGS and Virginia Tech scientists captured female northern bats and fitted them with tiny radiotransmitters and numbered armbands. The bats were then released and tracked to determine what roosts they were using.
Since first discovered in 2007 in New York, white-nose syndrome has spread to 16 states, including Virginia and Maryland, and four Canadian provinces. The disease is estimated to have killed over five million hibernating bats.
Since first discovered in 2007 in New York, white-nose syndrome has spread to 16 states, including Virginia and Maryland, and four Canadian provinces. The disease is estimated to have killed over five million hibernating 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.
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.
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Related Content
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...
Do vampire bats really exist?
Yes, but not in most of the United States. Of the three species of vampire bats in North America, only a single specimen has been recorded for the United States in extreme southwest Texas. Vampire bats do not suck blood--they make a small incision with their sharp front teeth and lap up the blood with their tongue. Vampire bats in Mexico and South America feed on the blood of livestock such as...
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...
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...
What species of bats are affected by White-nose Syndrome?
White-nose Syndrome mostly affects hibernating bats. More than half of the 47 bat species living in the United States and Canada hibernate to survive the winter. Twelve bat species , including two endangered species and one threatened species, have been confirmed with white-nose syndrome in North America. The causative fungus, Pseudogymnoascus destructans ( Pd ), has been found on an additional...
What is White-nose Syndrome?
White-nose syndrome is an emergent disease of hibernating bats that has spread from the northeastern to the central United States at an alarming rate. Since the winter of 2007-2008, millions of insect-eating bats in at least 40 states and eight Canadian provinces have died from this devastating disease. The disease is named for the white fungus, Pseudogymnoascus destructans , that infects skin of...
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...
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
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.
A little brown bat (Myotis lucifugus) with white-nose syndrome hibernating in a Virginia cave during late spring of 2016.
A little brown bat (Myotis lucifugus) with white-nose syndrome hibernating in a Virginia cave during late spring of 2016.
Dissected guano pellet showing antennae, eyes, and body fragments of midges.
Dissected guano pellet showing antennae, eyes, and body fragments of midges.
Bats benefit from maintaining a close-knit roosting group because they increase reproductive success and it is important for rearing pups.
Bats benefit from maintaining a close-knit roosting group because they increase reproductive success and it is important for rearing pups.
Imagery from temperature-sensing cameras showing bats in hibernation. This new footage suggests that bats who warm up from hibernation together throughout the winter may be better at surviving white nose syndrome, a disease caused by a cold-loving fungus ravaging insect-eating bat populations in the United States and Canada.
Imagery from temperature-sensing cameras showing bats in hibernation. This new footage suggests that bats who warm up from hibernation together throughout the winter may be better at surviving white nose syndrome, a disease caused by a cold-loving fungus ravaging insect-eating bat populations in the United States and Canada.
When bats detect an insect from returned echolocation calls they rapidly increase the pulse rate and raise the frequency of calls in order to gather more information on the insect including location. These calls emitted right before a bat closes in on an insect are called terminal phase calls or "feeding buzzes".
When bats detect an insect from returned echolocation calls they rapidly increase the pulse rate and raise the frequency of calls in order to gather more information on the insect including location. These calls emitted right before a bat closes in on an insect are called terminal phase calls or "feeding buzzes".
USGS and Virginia Tech scientists captured female northern bats and fitted them with tiny radiotransmitters and numbered armbands. The bats were then released and tracked to determine what roosts they were using.
USGS and Virginia Tech scientists captured female northern bats and fitted them with tiny radiotransmitters and numbered armbands. The bats were then released and tracked to determine what roosts they were using.
Since first discovered in 2007 in New York, white-nose syndrome has spread to 16 states, including Virginia and Maryland, and four Canadian provinces. The disease is estimated to have killed over five million hibernating bats.
Since first discovered in 2007 in New York, white-nose syndrome has spread to 16 states, including Virginia and Maryland, and four Canadian provinces. The disease is estimated to have killed over five million hibernating 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.
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.