Echolocation is similar to sonar: bats call as they fly and listen for how long it takes for the sounds to return, enabling the bats to calculate an insect’s distance.

Bats and Halloween have been connected for a long time. That could be due to the work of author Bram Stoker, who in his 1897 novel Dracula wrote about a human vampire who could transform into a bat; or it may have come about naturally because bats are generally nocturnal, and three species—out of approximately 1,200—feed primarily on blood.

However the Halloween-bat link was forged, what bats mostly drink is water. While we know how bats use a high-frequency system called echolocation to pinpoint insects in the dark, how they recognize ponds or other water bodies was less understood—until recently.

In the video below titled Bat Sense, produced by Nature Video, the stunning, slow-motion footage comes from a study that is the first to show how bats use echolocation to find large, flat objects, such as ponds. As a bat flies, it sends out high-pitched squeaks. It listens for the length of time and the patterns of the returning echoes, which allow the bat to build a sonic map of its surroundings. Flying over a lake or a pond, a bat would hear no echoes from up ahead; only ones reflected back from straight below. In nature, bodies of water are the only large, smooth surfaces around.

When researchers placed a metal plate on a table so that bats could echolocate underneath it, they still tried to drink from its surface. ©From the video “Bat Sense” by Nature Video

The man-made world, however, is full of level surfaces, including metal, plastic and varnished wood. When researchers released wild bats over smooth plates made of these materials, the animals tried to drink from them, too. If the plates were textured with small ridges, however, the bats ignored them.

The drive to drink from smooth-sounding surfaces is so strong that bats will ignore other cues, including the fact that the materials feel, look and smell different. Every adult bat involved in the study did the same thing, and some tried their luck a hundred times or more. Even individuals that had accidentally landed on the plates would try to drink from them later, despite their firsthand experience.

Researchers in the study also found that bats don’t need to learn this skill; it appears to be innate. Bats raised in captivity that had never encountered a pond or river before still tried to drink from a smooth, metal plate in the same way that the wild bats did. This marks the first evidence for innate recognition of a habitat cue in a mammal.

Here’s hoping this amazing video will quench your thirst for a Happy—and bat-appreciative!—Halloween,