These birds use echolocation to locate their roost in dark caves. Unlike a bat's echolocation, Aerodramus swiftlets make clicking noises that are well within the human range of hearing. The clicks consist of two broad band pulses (3–10 kHz) separated by a slight pause (1–3 milliseconds).

How do Oilbirds Echolocate?

How does the echolocation work? Oilbirds emit short bursts of clicking noises, which bounce off of objects in the animals' paths, creating echoes. The echoes return to the birds' ears at different levels of loudness and intensity. The larger the object, the more sound waves that are deflected, making the echoes louder.

Do birds use echolocation?

Echolocation is rare among birds. Two species of birds that live in caves and are known to have developed echolocation are South American oilbirds and swiftlets. Oilbirds emit clicks and use the echoes to hep them navigate in total darkness.