Ironically, the painted bat’s protective orange and black camouflage makes it stand out to predators who would likely never spot it in its natural habitat. 

Internet-surfing Halloween decorators and wildlife collectors are fueling a growing trade in the preserved corpses of this near-threatened species, adding to the number of threats faced by declining bat populations worldwide.

Although painted bats are caught and killed in their home range of southeast Asia, western nations are driving the market. The lion’s share of buyers are located in the United States, and many purchasers are unaware that the sellers’ claims of sustainable harvesting are false. Experts agree that these specimens are collected from declining wild populations.

Dave Waldien is a visiting assistant teaching professor in William & Mary’s Department of Biology who has specialized in bat conservation for more than 25 years. He is currently mentoring a group of undergraduate students who are contributing to bat conservation research. Hands-on research experiences like these give W&M students the opportunity to work closely with faculty like Waldien as part of the university’s efforts to provide the most personal education of any public university in the United States.

“My interest in bats goes all the way back to when my mom read the book “Stellaluna” to me as a little kid,” said Charlotte Toomey ’26. “Now that I’ve had the opportunity to get involved with research on campus, I’ve learned how bats like Stella are vital to ecosystems around the world, and I’m able to contribute to bat conservation efforts.”

Beneficial bats

“Bats are really unique and special,” said Waldien. “They do many amazing things that are valuable to ecosystems and to humans.”

For example, many species of bats are voracious insectivores. Here in the United States, the furry fliers save farmers billions of dollars in pest control costs every year.

In the tropics, nectar-sipping bat species pollinate crops like bananas, avocados, mangos and agaves, including agaves that are used in tequila. Worldwide, more than 300 species of fruit depend on bats for pollination.

Fruit-eating bats, meanwhile, disperse a wide variety of seeds, including those of nut, fig and cacao trees. With a dispersal range of up to 75 kilometers, bat-aided seed distribution plays a key role in forest regeneration and maintaining the genetic diversity of trees and crops. 

Waldien also notes that bats are fascinating in and of themselves. With more than 1,460 species of bats around the world, they’re incredibly diverse.

“Some weigh about as much as a penny,” he said, “and others have a wing span approaching five and a half to six feet. Some of them look like little puppy dogs, and others have other unique appearances due to physical modifications for acquiring different types of food.”

Bats are also nimble fliers with a penchant for aerial gymnastics. Chiroptera is the order that encompasses all bat species. The name translates to “hand wing,” a description of the complex structure of bat wings that resembles a modified human hand and contributes to their agile mid-air maneuvers.

“They’re amazingly acrobatic in their flight patterns,” Waldien said. “Some of them just do loops around you.”

Bats’ aerial feats have inspired new drone and robotic technology, while their echolocation abilities have influenced the development of compact, efficient sonar systems and ultrasonic canes to aid the visually impaired.

Globally, bat populations are declining

Mature females of most bat species produce only one pup per year. This slow reproductive rate is a major factor in the vulnerability of global bat populations to a range of ongoing threats, including climate change, collisions with wind turbines, persecution spurred by fear and misinformation, hunting for the bushmeat trade and unsustainable guano harvesting.

Introduced diseases also take a toll. For example, white nose syndrome, a fungus from Europe, has killed millions of bats in North America, including approximately 90% of three once common species. Since it was first detected in New York in 2006, the disease has spread to 40 U.S. states and eight Canadian provinces.

Waldien explained that the largest driver of bat population declines, however, is habitat loss – particularly due to deforestation and decreased availability of cave roosting sites. Habitat provides species with food, water, shelter and places to raise young, so the loss of these areas has significant impacts on the species who depend upon them.

In order to aid in preserving habitat for bats, Waldien works to ensure that bats are considered when key biodiversity areas (KBAs) are identified. Pinpointing these hotspots of biodiversity helps governments to determine which lands to prioritize for conservation.

“KBAs are identified through scientific global standards and are important to biodiversity conservation,” said Waldien. “We’re mobilizing and catalyzing the global bat-expert  community to get involved and to ensure that bats are considered when KBAs are updated.”

A key tool in determining KBAs is The International Union for Conservation of Nature’s Red List of Threatened Species, which inventories the global conservation status and extinction risk of biological species throughout the world. Waldien serves as the Old World Bat Coordinator for the Red List Authority and coordinates and completes assessments with bat researchers and students around the world — including here at W&M. 

For conservation to succeed, he explained, it’s essential to work with local communities, and long-term relationships are the most productive as they help ensure a project is sustainable.

“If you treat people with respect, listen to their concerns and engage with them based on their culture, then they respond very well to conservation efforts,” he said. 

Student bat conservation research

Anika Srikanth ’25 is developing a geospatial map that supports an Indigenous initiative to update a KBA in Bougainville, Papua New Guinea. The local clans have established three zones to guide management of their resources, including tambu (sacred), traditional use and community use areas. Working with the local people, Srikanth and Waldien will propose the update to the KBA.

Meanwhile, 10 other students are updating Red List assessments. Their work involves collating information and navigating a challenging writing process to present the information that they’ve gathered to the IUCN.

Charlotte Toomey ’26 is working on a Red List assessment of the long-haired fruit bat, a megabat native to Africa, and has also recently begun reviewing data for a project evaluating bat use of mine culverts in Mexico.

“My particular research on bat use of culvert-gates in mines enables cave-roosting species to make use of the vital habitat without human disturbance,” said Toomey, “and my work on assessing the long-haired fruit bat for the IUCN Red List provides a framework for how to improve conservation efforts and builds upon pre existing ecological data.”

How can non-scientists help bats?

First and foremost, said Waldien, bats need ambassadors to raise awareness of their importance, dispel myths and promote conservation of bats and their habitat.

As all of the bats in the Williamsburg area eat night-flying insects, W&M bat enthusiasts can provide local habitat by planting a bat garden with night-blooming native plants to attract moths and other nighttime insects. In addition to nectar-producing flowers, it’s best to include host plants to feed moth caterpillars, thus ensuring a steady supply of prey. Minimizing pesticide use can also help to ensure that bats have plenty of healthy snacks to devour. 

Nighttime lighting has been linked to declines in insect populations, which in turn decreases bats’ food supply. Additionally, when bats hunt insects that are attracted to outdoor lighting, the bats are more visible to predators. Thus, turning off lights at night or using motion detectors makes areas more bat-friendly.

Installing a bat house can be another effective way to provide habitat for bats, as these structures provide a safe roosting spot for female bats with pups.

Experts advise observing wildlife from a respectful distance. In the event that someone finds an injured or sick bat, the best course of action is to contact a permitted wildlife rehabilitator for assistance. For the protection of both bats and humans, it is important not to handle bats.

This Halloween and every day, Waldien advises taking a closer look at the benefits of bats and learning to appreciate them for their innate charms as well as the services that they provide.

“Even when you look at our local Virginia bats,” he said. “They may seem unremarkable because they’re small and uniform in color, but their capabilities are what won me over. Educate yourself on the diversity of bats around the world, their distinctiveness and their abilities. Never handle them, but be aware of them and get to know them for the special creatures that they are.”