Study Says Bats’ Munching Can Teach Other Bats

In a situation akin to finding a great new restaurant by being attracted to the satisfied sounds of happy customers, a new study shows that fringe-lipped bats can quickly learn to eat new prey by listening to neighbor bats eat.

The bats learn to associate a new frog call with food by listening to “tutor bats” that have already made this association, according to the study published Tuesday in the journal Current Biology.

Working at the Smithsonian Tropical Research Institute on Barro Colorado Island in Panama, biologists Rachel Page and Michael Ryan of the University of Texas at Austin conditioned bats to associate the recorded call of a poisonous cane toad, which they do not eat, with a food reward. These bats were then put in outdoor flight cages with untrained bats.

Within 5.3 trials, on average, the untrained bats learned from tutor bats to approach the toad’s call for food.

Without tutoring, most bats did not respond to the toad call after 100 trials.

The bats seemed to learn about the suitability of the new food by hearing the tutors eat their reward, Page said.

Very rarely, bats would respond to the cane toad calls without the benefit of a tutor bat. This rare behavior may be how a novel food source is initially introduced to a group of bats, the report said.

Studies are investigating whether such eating sounds alone, without a tutor bat present, can teach the fringe-lipped bat to eat a new prey.

The study is the first to show that predators can learn from others of its kind about the acoustic cues of their prey -- essentially, what good food sounds like.

Previous studies have shown such social learning about visual and olfactory prey cues.

The ability to learn quickly from others to eat something new may be an important survival mechanism, allowing the bats to respond rapidly to changes in the availability of prey.