The flighty science of studying bats

By: Andrew Avitt, Oct. 27, 2020-


A picture of Susan Loeb weighing a bat.
Susan Loeb, a USDA Forest Service research ecologist, weighs a bat in Stumphouse Tunnel, a hibernaculum in northwestern South Carolina that she has been monitoring since 2014. Loeb played a critical role in coordinating the efforts of many different agencies and initiating the North American Bat Program in 2015. (USDA Forest Service photo.)

Bats are flighty creatures of nocturnal and reclusive nature. Perhaps it is that very nature that made monitoring bat populations in North America a challenge. At least that was until the North American Bat Monitoring Program (NABat) was first implemented in 2015, which facilitated mass coordination of scientists and data across the continent. Susan Loeb, a research ecologist with the USDA Forest Service at the Southern Research Station remembers how the necessity for the program became apparent.

“In the late 90’s researchers were starting to realize the importance and threats of bat populations and that there was insufficient coordinated data on a number of topics,” said Loeb, who has been working as a researcher with the Forest Service since 1988.

Data related to disease (white-nose syndrome), climate change, wind turbine fatalities, habitat fragmentation were scarce and uncoordinated making the standardization of data collection of the NABat essential to understanding bat-related issues.

“Prior to 2015, we were observing influences of human and natural related effects on bats, but we had no real documentation on what was happening to bats across the continent except for those bats that inhabit caves in the eastern United States,” Loeb said.

In 2012, Loeb had a lead role in coordinating the program along with other national and international wildland agencies and private sector organizations across the U.S. and Canada – including the U.S. Fish and Wildlife Service, Canadian Wildlife Service, and Bat Conservation International. Together, these organizations began to develop a large scale and long-term monitoring program for North America.

A big part of instituting the North America Bat Monitoring Program was coming up with a standard sampling framework which is scalable, allowing sampling across large areas, such as a state, and smaller areas such as national forests, which allows information to be contributed to a universal data bank.

A picture of a bat.
Data collected through the North American Bat Monitoring Program allows researchers and land managers to look at changes in distribution and relative abundance of bats and continue monitoring those changes within a given landscape. (USDA Forest Service photo.)

“We started with nothing, now NABat is conducted in 42 U.S. states and six Canadian provinces,” said Loeb. “The result is that we are now able to monitor bat species that we were never able to track before.”

Five years after the implementation of the program, those issues are coming into focus as researchers pool their data, providing natural resource managers with the information they need to make informed decisions, to detect early warning signs of bat population declines, and estimate extinction risks.

“We have made tremendous progress, but there is still work to be done,” said Loeb. “We are still refining the methods and protocols of our sampling and surveys, and several studies have been published based on the results of NABat which help define distributions of bats.”

Loeb says the data will enable researchers to look at changes in distribution and relative abundance of bats and monitor continuing changes within a given landscape, changes due to land use, land management, climate change, habitat fragmentation, and disease, and shed light on how those variables are affecting our bat populations. The benefits that bats bestow on the land and humanity are more than worth the scientific field’s attention.

“There is so much more that we have yet to learn from bats,” says Loeb, “and with the North American Bat Monitoring Program we can ensure that bat populations thrive into the future so that we can continue learning from them.”