Bats in the Cuyahoga Valley


This week on our Field Notes blog, it’s a timely celebration of some spooky mammals for International Bat Week! These remarkable animals are the only mammals capable of flight. They also play a huge role in keeping our insect populations in check: In the summer, some bat species eat more than 1,000 mosquitoes an hour. Despite their creepy reputation, bats are remarkable creatures that we hope you’ll learn to love.

Here at the Conservancy, we’re committed to connecting you with your national park—and, this week, helping you learn more about the creatures that call it home, like bats. Did you know there are seven species of bats found in the Cuyahoga Valley? Here are five cool facts to share with your friends about bats in Ohio’s national park:


  1. Bats navigate in the dark by using objects to reflect sound. This process, called echolocation, helps bats avoid obstacles and catch insects in total darkness. To find their way, bats send out calls or clicks (mostly beyond the range of the human ear) and listen for the echoes bouncing off nearby objects. When searching for prey, they send out clicks at a relatively low rate—about 10-20 clicks per second. When they get close to catching their meal, they increase the rate, ending with the “terminal buzz”—up to 200 clicks per second!


  1. The hoary bat is the largest bat in Ohio—and in CVNP—with a wingspan measuring up to 17 inches. The second-largest is the aptly-named big brown bat. Even these larger bats are quite light and agile, and not the fearsome predators that many perceive them to be. (And don’t worry: Of the three species of vampire bats in the world—that is, bats who feed solely on blood—none are found in North America.)


The big brown bat—shown here hibernating—is one of the largest bats in CVNP (Photo: U.S. Fish and Wildlife Service)

3. The Indiana bat is the only federally endangered bat species found in the park. These bats tend to hibernate in large numbers in only a few caves, making them susceptible to human disturbance, pesticide use, habitat loss, and White-Nose Syndrome (see below for more information). Currently, work is being done throughout the nation to protect and expand critical habitat for these fuzzy critters.

The small Indiana bat is a federally endangered species (Photo: U.S. Fish and Wildlife Service)

4. Some CVNP bats—including hoary bats and red bats—migrate to warmer climates for the winter, just like birds. Although little is known about their migration route or range, some red bats may fly all the way to Central America! Other bats hibernate through the winter, typically clustered together in caves.

5.  Bats are insect-eating machines. A big brown bat can eat 1,200 mosquitoes each hour, and up to 8,000 insects each night! They catch bugs by swooping through the night sky and eating their dinner mid-air. Instead of swatting at bats, we should be thanking them: Without their help, we’d be overwhelmed by all the pesky bugs at the Beaver Marsh, Ledges, and other places in the park.

Bats are suffering grave declines in CVNP and throughout the U.S. because of a deadly fungal infection called White-Nose Syndrome. The disease has been devastating to bats in North America, with some populations declining by more than 90 percent. Humans are not affected by the disease but can spread it by tracking fungal spores on their shoes or clothing into caves or other bat habitats. Learn more >  

Red bats migrate long distances for the winter (Photo: Chris Harshaw, CC BY-SA 3.0)

You can help prevent the spread of White-Nose Syndrome by avoiding going into caves where bats hibernate, like Ice Box Cave along the Ledges Trail. While it may be disappointing to pass up a spelunking expedition, you’ll feel good knowing you’re helping to protect these extraordinary creatures.

On behalf of all of us here at the Conservancy, have a safe, spooky, and fun Halloween! Be sure to visit CVNP around dusk and turn your eyes skyward, and you may just spot some of CVNP’s remarkable bats.