Bats Use Ears Instead of Ultrasound to Hunt Close to the Ground

Bats Use Ears Instead of Ultrasound to Hunt Close to the Ground

This is the latest discovery by Swiss scientists about the hunting techniques of bats. Typically, bats emit ultrasound to locate prey through echo feedback. However, when hunting near the ground, where objects interfere with sound waves, bats rely on their ears to “listen” for prey.

A research team led by Raphael Arlettaz at the University of Bern, along with colleagues from the University of Lausanne, studied two common bat species: Myotis myotis (large-eared) and Myotis blythii (small-eared). Video recordings revealed that as bats fly closer to the ground, they reduce their ultrasound emissions (only using enough to navigate). At this point, bats rely on their highly sensitive ears to detect prey. Their hearing is so acute that they can detect the sound of an insect jumping from one blade of grass to another.

The team’s observations also showed that bats are more effective at hunting in flat areas compared to rough surfaces. This is because the ultrasound waves emitted by bats reflect better off smooth surfaces. Interestingly, when hunting over a calm water surface, bats, even when flying close to the water, continue to use ultrasound for locating prey.