Bats make up one-fifth of all mammalian species worldwide and are found on every continent except Antarctica. They contribute to overall ecosystem health by suppressing pest insects and pollinating plants and spreading seeds. Eight North American bat species are listed as federally endangered or threatened, and more than one-half are of current conservation concern in the United States, Canada, or Mexico.
We conduct scientific research on bats that helps resource managers and policymakers make informed decisions regarding the conservation of bats across North America. USGS science also helps inform decision making with respect to white-nose syndrome (WNS) surveillance and bat vulnerability; mitigation of potential impacts of energy development on bats; prelisting conservation efforts for regulatory agencies; and land management practices.
About Bats
Bats remarkably similar to the ones we have today first appeared on Earth more than 50 million years ago. No other mammal has ever achieved the ability to sustain flight.
There are more than 1,300 species of bats, some the size of a human thumb and others with a six-foot wingspan. Most bats eat insects, many eat fruit and nectar from plants, some eat rodents, and yes, some consume blood. All are primarily active at night. Many species of bats rely on echolocation (locating objects by reflected sound) and incredible dim-light vision to navigate through the night and in the caves and tree-roosting sites they inhabit.
“Many people think bats are blind, but they actually have really sensitive vision, which helps them see in conditions we might consider pitch black,” said Paul Cryan, a bat ecologist with the USGS. “They don’t have the sharp and colorful vision we do, but they don’t need that. Think a dark-adapted Mr. Magoo.”
During winter, many species of bats hibernate in cool and moist caves or mines. Hibernation is an adaptation for bat survival during cold winter months, when there are no insects available for bats to eat. Bats must store energy in the form of fat prior to hibernation. One of the consequences of WNS is that the hibernation of many afflicted bats is interrupted, often causing them to depart their winter roost early and eventually starve to death.
Bat reproduction begins with mating in the fall before hibernation, yet new USGS research revealed that a surprising amount of mating also occurs during winter hibernation. Female bats store sperm throughout the winter and become pregnant in the spring soon after emerging from caves or other winter roosts. In spring, bats migrate to their summer territories, often in wooded locations with lots of trees and vegetation. Females usually roost together in maternity colonies under the peeling bark or in cavities of dead and dying trees, and in other structures in groups of up to 100 or more. Each female in the colony typically gives birth to only one pup per year. Young bats are nursed by the mother, who leaves the roost only to forage for food. While mothers are out foraging, the young bats huddle together in groups that biologists call a cuddle. The young stay with the maternity colony throughout most of their first summer.
Bats remain a frontier of wonder and discovery. Scientists recently discovered that bats are among the longest-lived mammals for their size and may hide biological secrets to longevity. We also now know that bats are more closely related to horses, dogs and cats than to any other mammals.
“These mysterious creatures will undoubtedly continue to benefit us as they fly above our heads in the dark, and science can help us discover and help protect those free and irreplaceable benefits,” Cryan said.
Bat Research
Ecology of Wildlife Disease
Non-invasive Surveillance of Bat Hibernacula to Investigate Potential Behavioral Causes of Mortality Associated with White Nose Syndrome
Ecological Investigations of White-Nose Syndrome in Bats
External Microbiota of Bats as Potential Bio-control Against Wildlife Diseases
White-Nose Syndrome Threatens the Survival of Hibernating Bats in North America
Bat Population Data Project
Bat Banding Clearinghouse
Ecology of Insect-eating Bats
Bat Fatalities at Wind Turbines—Investigating the Causes and Consequences
Bat Species of Concern: An Ecological Synthesis for Resource Managers
Surveillance for the Presence of White-Nose Syndrome in the Bat Community at El Malpais National Monument, New Mexico
Assessing Impacts to Ecosystems from Uranium Mining in the Grand Canyon Region
High Elevation Cave Surveys for Bats and White Nose Syndrome
Data related to USGS bat research is listed below.
Oahu multi-state occupancy models of foraging habitat use by Hawaiian hoary bats 2017
Hawaii Island Hoary Bat Acoustic and Visual Surveys 2014
Recent publications (2020-2022) related to USGS bat research are listed below. A complete listing of USGS bat publications is available from the button below.
Monitoring and modeling tree bat (Genera: Lasiurus, Lasionycteris) occurrence using acoustics on structures off the mid-Atlantic coast—Implications for offshore wind development
White-nose Syndrome and environmental correlates to landscape-scale bat presence
Mycobiome traits associated with disease tolerance predict many western North American bat species will be susceptible to white-nose syndrome
Forecasting the distribution of a range-expanding bat reveals future response to climate change and habitat
Fire, land cover, and temperature drivers of bat activity in winter
White-nose syndrome-related changes to Mid-Atlantic bat communities across an urban-to-rural gradient
The scope and severity of white-nose syndrome on hibernating bats in North America
Historical effective population size of North American hoary bat (Lasiurus cinereus) and challenges to estimating trends in contemporary effective breeding population size from archived samples
Risks posed by SARS‐CoV‐2 to North American bats during winter fieldwork
The virus that causes COVID‐19 likely evolved in a mammalian host, possibly Old‐World bats, before adapting to humans, raising the question of whether reverse zoonotic transmission to bats is possible. Wildlife management agencies in North America are concerned that the activities they authorize could lead to transmission of SARS‐CoV‐2 to bats from humans. A rapid risk assessment conducted in Apri
Behavioral patterns of bats at a wind turbine confirm seasonality of fatality risk
Analysis of archival specimens confirms White-nose syndrome in little brown bats (Myotis lucifugus) from New York, USA, in spring 2007
NABat: A top-down, bottom-up solution to collaborative continental-scale monitoring
News article about USGS bat research are listed below.
Bats make up one-fifth of all mammalian species worldwide and are found on every continent except Antarctica. They contribute to overall ecosystem health by suppressing pest insects and pollinating plants and spreading seeds. Eight North American bat species are listed as federally endangered or threatened, and more than one-half are of current conservation concern in the United States, Canada, or Mexico.
We conduct scientific research on bats that helps resource managers and policymakers make informed decisions regarding the conservation of bats across North America. USGS science also helps inform decision making with respect to white-nose syndrome (WNS) surveillance and bat vulnerability; mitigation of potential impacts of energy development on bats; prelisting conservation efforts for regulatory agencies; and land management practices.
About Bats
Bats remarkably similar to the ones we have today first appeared on Earth more than 50 million years ago. No other mammal has ever achieved the ability to sustain flight.
There are more than 1,300 species of bats, some the size of a human thumb and others with a six-foot wingspan. Most bats eat insects, many eat fruit and nectar from plants, some eat rodents, and yes, some consume blood. All are primarily active at night. Many species of bats rely on echolocation (locating objects by reflected sound) and incredible dim-light vision to navigate through the night and in the caves and tree-roosting sites they inhabit.
“Many people think bats are blind, but they actually have really sensitive vision, which helps them see in conditions we might consider pitch black,” said Paul Cryan, a bat ecologist with the USGS. “They don’t have the sharp and colorful vision we do, but they don’t need that. Think a dark-adapted Mr. Magoo.”
During winter, many species of bats hibernate in cool and moist caves or mines. Hibernation is an adaptation for bat survival during cold winter months, when there are no insects available for bats to eat. Bats must store energy in the form of fat prior to hibernation. One of the consequences of WNS is that the hibernation of many afflicted bats is interrupted, often causing them to depart their winter roost early and eventually starve to death.
Bat reproduction begins with mating in the fall before hibernation, yet new USGS research revealed that a surprising amount of mating also occurs during winter hibernation. Female bats store sperm throughout the winter and become pregnant in the spring soon after emerging from caves or other winter roosts. In spring, bats migrate to their summer territories, often in wooded locations with lots of trees and vegetation. Females usually roost together in maternity colonies under the peeling bark or in cavities of dead and dying trees, and in other structures in groups of up to 100 or more. Each female in the colony typically gives birth to only one pup per year. Young bats are nursed by the mother, who leaves the roost only to forage for food. While mothers are out foraging, the young bats huddle together in groups that biologists call a cuddle. The young stay with the maternity colony throughout most of their first summer.
Bats remain a frontier of wonder and discovery. Scientists recently discovered that bats are among the longest-lived mammals for their size and may hide biological secrets to longevity. We also now know that bats are more closely related to horses, dogs and cats than to any other mammals.
“These mysterious creatures will undoubtedly continue to benefit us as they fly above our heads in the dark, and science can help us discover and help protect those free and irreplaceable benefits,” Cryan said.
Bat Research
Ecology of Wildlife Disease
Non-invasive Surveillance of Bat Hibernacula to Investigate Potential Behavioral Causes of Mortality Associated with White Nose Syndrome
Ecological Investigations of White-Nose Syndrome in Bats
External Microbiota of Bats as Potential Bio-control Against Wildlife Diseases
White-Nose Syndrome Threatens the Survival of Hibernating Bats in North America
Bat Population Data Project
Bat Banding Clearinghouse
Ecology of Insect-eating Bats
Bat Fatalities at Wind Turbines—Investigating the Causes and Consequences
Bat Species of Concern: An Ecological Synthesis for Resource Managers
Surveillance for the Presence of White-Nose Syndrome in the Bat Community at El Malpais National Monument, New Mexico
Assessing Impacts to Ecosystems from Uranium Mining in the Grand Canyon Region
High Elevation Cave Surveys for Bats and White Nose Syndrome
Data related to USGS bat research is listed below.
Oahu multi-state occupancy models of foraging habitat use by Hawaiian hoary bats 2017
Hawaii Island Hoary Bat Acoustic and Visual Surveys 2014
Recent publications (2020-2022) related to USGS bat research are listed below. A complete listing of USGS bat publications is available from the button below.
Monitoring and modeling tree bat (Genera: Lasiurus, Lasionycteris) occurrence using acoustics on structures off the mid-Atlantic coast—Implications for offshore wind development
White-nose Syndrome and environmental correlates to landscape-scale bat presence
Mycobiome traits associated with disease tolerance predict many western North American bat species will be susceptible to white-nose syndrome
Forecasting the distribution of a range-expanding bat reveals future response to climate change and habitat
Fire, land cover, and temperature drivers of bat activity in winter
White-nose syndrome-related changes to Mid-Atlantic bat communities across an urban-to-rural gradient
The scope and severity of white-nose syndrome on hibernating bats in North America
Historical effective population size of North American hoary bat (Lasiurus cinereus) and challenges to estimating trends in contemporary effective breeding population size from archived samples
Risks posed by SARS‐CoV‐2 to North American bats during winter fieldwork
The virus that causes COVID‐19 likely evolved in a mammalian host, possibly Old‐World bats, before adapting to humans, raising the question of whether reverse zoonotic transmission to bats is possible. Wildlife management agencies in North America are concerned that the activities they authorize could lead to transmission of SARS‐CoV‐2 to bats from humans. A rapid risk assessment conducted in Apri
Behavioral patterns of bats at a wind turbine confirm seasonality of fatality risk
Analysis of archival specimens confirms White-nose syndrome in little brown bats (Myotis lucifugus) from New York, USA, in spring 2007
NABat: A top-down, bottom-up solution to collaborative continental-scale monitoring
News article about USGS bat research are listed below.