Nobody has seen anything like this in any other animals which echolocate. It’s not necessarily surprising that they’re competing with each other [for food] but the fact that they’ve evolved this jamming signal is quite new.
“When a bat is just about to capture a moth we know they are susceptible to jamming at that point. When we look at it from an acoustics or physics point of view, the jamming sounds are produced at the right time and made at the right frequency that match the frequency the other bats are using,” said Aaron Corcoran, a researcher from the Wake Forest University, North Carolina, who was studying moths but accidently discovered that a species of bat steals the foods of other bats by making a jamming sound.
Corcoran discovered by pure chance that the Mexican free-tailed bat emits a sound that jams the calls of a rival bat who is honing in on an insect prey, making the rival bat to miss its target and the Mexican free-tailed bat capturing the insect prey for itself. It is a perfect genius that allows the bat specie to steal the food of its rivals at the precise moment, just be making a high-pitched frequency sound that jams and disorients the rival at the moment of going for the kill.
Dr. Corcoran noted further during his research with the Mexican free-tail bat that “one bat was trying to capture an insect using its echolocation. The second bat was making another sound that looked to me like it might be trying to jam or disrupt the echolocation of the other bat. Most of the time when another bat was making this jamming call, the bat trying to capture the moth would miss”.
To further prove what he had seen, Corcoran illuminated the night sky with a spotlight, and attached a camera which he used to record bats as they captured insects. He also reconstructed the flights of the bats in order to measure their position when they emitted the sounds – this he achieved by placing microphones at various flight locations to measure time differences between sounds. The map of the bats flight or trajectories was stitched together to obtain all sounds made by any particular bat while honing in for the kill. The recorded sounds were played back to other bats when they were about to catch moths, and it jammed their hunt in exactly the manner described – only other recorded bat sounds failed to produce this result.
“Technology is opening up our understanding of these deeply cryptic creatures,” noted Prof. Kate Jones of the University College London, and Dr. Kate Barlow of the Bat Conservation Trust added that “this study reveals another way in which bats have learnt to take advantage of their competitors by listening out for their feeding buzzes…presumably with the intention of then sneaking in and catching insect for themselves. Very sneaky!”