‘Bag of chips effect’ helps bats find a meal

Sounds of other bats feeding reveal prey locations

greater mouse-tailed bat

ALL EARS  The greater mouse-tailed bat listens for other bats to deduce where prey cluster.

Jens Rydell

Bag of chips effect
BAG uhv CHIHPS ih-fekt n.

A circumstance in which the sounds of one individual eating alerts others to the location of food.

Researchers have found that hungry bats find dinner by listening for their peers zeroing in on prey. When greater mouse-tailed bats (Rhinopoma microphyllum) spot a meal with echolocation, they emit a “feeding buzz” made up of many short cries that helps them lock in on their prey: flying ants. The bats can hear an insect 10 meters away but can detect their fellow bats’ feeding buzz from 100 meters away, a sound that, like a rustling bag of chips, gives away the location of a snack.

Then the bats swoop over to where the munching bat is and help themselves to other flying ants in the area, researchers report in the Jan. 19 Current Biology.