View from inside a Tennessee cave.
Cave Opening Opening of a cave in the southern Cumberland Plateau. © Stephen Alverez

Stories in Tennessee

Tennessee Caves

Twenty percent of known caves in the United States are located in Tennessee.

Nearly one thousand species, mostly crustaceans, insects and arachnids, live exclusively in caves within the lower 48 states. Twenty percent of known caves in the United States (10,000+) are located in Tennessee. The federal government has not extended the protection of the Endangered Species Act to most of our nation’s cave creatures, even though most are highly vulnerable.

Tri-colored bat in Tennessee cave.
Tri-Colored Bat, Tennessee Tri-colored bats, once plentiful in the U.S., have been hard hit by deadly white-nose syndrome. © Cory Holliday/The Nature Conservancy

Protecting Cave Ecosystems

Preserving cave ecosystems represents one of The Nature Conservancy’s highest priorities in Tennessee, for good reason. Little is known about the animals living in this complex subterranean landscape. Caves contain critical habitat that bridges fields and forests with groundwater below. 

In 2001, TNC worked with world-renowned zoologist Dr. Julian Lewis on the largest cave-survey ever undertaken in the state on 100 caves located in the Cumberland Plateau. The results revealed astounding results: 48 previously unknown species, as well as more than 150 insects considered globally rare. TNC uses this information to develop conservation strategies for these delicate ecosystems.

This work begins on land. Subterranean systems depend on water and debris entering from sinkholes and other entrances to nourish cave-adapted species. Areas surrounding caves are critical to animals that exit to feed at night, like bats and cave crickets. Alterations to the landscape and water table surrounding a subterranean system can affect both the quality and quantity of food and water reaching a cave.

Help Save Bats Find out how you can help us save bats from White-Nose Syndrome (WNS).

Understanding White-Nose Syndrome in Bats 

Tennessee’s best known cave dwellers are bats, including gray bats and Indiana bats which are both listed as endangered species. Depending on the species, bats use caves for hibernation, maternity and as a respite during migration, forming colonies numbering in the thousands and sometimes the hundreds of thousands.

Bats are especially sensitive to disturbances in caves. Waking bats during winter hibernation causes them to use energy stored to survive the season. Disturbances during summer threaten young bats in maternity colonies that have yet to take flight.

Over the past decade, an epidemic called white-nose syndrome (WNS) has devastated bat populations in the eastern United States and Canada. The culprit, an invasive fungus called Pseudogymnoascus destructans (Pd.), damages the wings of cave-dwelling bats. Infected bats wake more frequently during winter hibernation and exhaust critical stores of fat required to get through the winter. Most caves where the fungus has appeared have resulted in bat die-offs of 90 percent or more for vulnerable species.

In response, TNC works with partners to monitor bat populations in caves across Tennessee to determine how WNS is affecting bats and share data that will inform treatment of this disease. One project, which employs bacteria used to prevent bananas from ripening too fast, shows promise in stopping the growth of the WNS fungus. TNC continues to work with partners on this and other strategies seeking keys to controlling this disease.

Our subterranean work has expanded into collaborating with partners to study and understand some of the greatest challenges in caves and karst conservation, including white-nose syndrome and bat migrations.

TNC's Director of Protection in Tennessee

Bat Behavior Research

In an effort to learn more about bat behavior while on the wing in Tennessee, TNC scientists—together with colleagues from the Tennessee Wildlife Resources Agency and Copperhead Consulting—executed a ground and air-based radio telemetry study on foraging patterns in 2018. A year later, the same team executed a new study focused on migration patterns.

When gray bats migrate, they can fly faster and farther, for hundreds of miles, usually seeking out caves for rest. This study sought to answer the question of whether gray bats assume a straight line of flight or follow river corridors during summer migration. The prevailing theory favored the latter.

The data told a different story, revealing that gray bats traveled between their hibernacula and summer roosting spots in a straight line. The information will guide future efforts to protect gray bats at every point in their life cycle, especially in light of wind development projects proposed in the state. 

More on Cave Conservation