The Indiana bat (Myotis sodalis) is a small, mouse-eared bat native to North America, primarily found in the eastern half of the United States. Despite common misconceptions, Indiana bats are generally not dangerous to humans when left undisturbed. Their nature is to avoid human contact, making direct interactions rare.
Behavior and Nature
Indiana bats are small, measuring 1.5 to 2 inches long with a wingspan of 9.5 to 10.5 inches, and weigh about a quarter of an ounce. They are primarily insectivorous, feeding on night-flying insects such as moths, beetles, and mosquitoes. A colony of Indiana bats can consume millions of insects each night, providing ecological benefits by controlling insect populations.
These bats are nocturnal, emerging at dusk to forage. They are known for their social behavior, forming large, dense clusters during hibernation in caves and mines, sometimes with thousands of individuals. During summer, females form maternity colonies, often under the loose bark of trees, to raise their single pup.
Health Risks
The primary health concern with bats, including Indiana bats, is the risk of rabies transmission. Rabies is a serious viral disease that can be fatal if not treated promptly. Transmission typically occurs through a bite or, rarely, when infected saliva or nervous tissue comes into contact with open wounds or mucous membranes.
Less than 1% of bats in the wild carry rabies. A bat that is rabid will often exhibit unusual behavior, such as being active during the day, struggling to fly, or being easily approached. While other infectious agents like histoplasmosis and salmonellosis can be associated with bats, these are extremely rare and typically linked to contact with guano or imported bats.
Safe Encounters
If you find an Indiana bat indoors, remain calm and avoid direct contact. Do not attempt to handle the bat with bare hands, as even a small bite or scratch can transmit diseases. Instead, try to guide the bat out by closing interior doors to confine it to one room and opening windows or doors leading outside. Turning off indoor lights can encourage the bat to fly towards the natural light outside.
If the bat does not leave on its own, wait for it to land, then carefully place a container, such as a plastic tub or shoebox, over it. Gently slide a piece of cardboard underneath to trap the bat inside before releasing it outdoors. If a bat has potentially bitten or scratched someone, or if it was found in a room with a sleeping person, an unattended child, or an impaired individual, the bat should be safely captured for rabies testing. Immediately wash any wound thoroughly with soap and water and seek medical attention.
Protecting Indiana Bats
The Indiana bat is listed as an endangered species under the Endangered Species Act. Their populations have declined significantly due to human disturbance of their hibernation sites, habitat loss, and diseases like white-nose syndrome. Minimizing human disturbance, especially in caves where they hibernate in large, dense clusters, is important for their survival.
Conservation efforts focus on protecting their hibernacula and summer roosting habitats, which include forests with suitable trees for maternity colonies. Understanding and respecting their natural behaviors and habitats supports their recovery and promotes coexistence.