Echolocation is the process of using sound waves to locate objects that may be invisible or at a distance. Some bats use sound to locate their insect prey. Bats have vocal chords modified to emit the high-frequency sounds needed for good resolution and specially adapted ears to receive the sound. Animals also use echolocation for orientation, avoiding obstacles, finding food, and for social interactions. The animal produces sounds and listens for the echoes reflected from surfaces and objects in its environment. By analyzing the information contained in these echoes, the animal can perceive the objects.

In all species that use echolocation, the sound pulses are short bursts at relatively high frequencies, ranging from about 1,000 Hz in birds to at least 200,000 Hz in whales. Bats use frequencies from about 30,000 Hz to about 120,000 Hz. The pulses are repeated at varying rates depending on what the animal is doing. A flying...