Water Ripples Aid Bats in Frog Hunting

2014-02-12 138

For the male tungara frog, mating is a risky business, often resulting in attacks by rivals and heightening the risk of getting eaten by a bat.

For the male tungara frog, mating is a risky business, often resulting in attacks by rivals and heightening the risk of getting eaten by a bat.

At the core of the problem is how they attract females – they serenade them.

Unfortunately, their singing happens in shallow waters and causes ripples to radiate from their amorous selves.

That type of water movement is picked up by one of their predators, bats using echolocation, making the frog an easy mark.

Overall, the species has developed enough of a self-defense strategy to stop making noises when bats are sighted, but if the water around them has already been disturbed, there’s not much they can do.

One expert explained, “The ripples continue to emanate out for several seconds, creating a watery bull’s-eye on the frog.”

To test what they’d observed, the researchers filled a pond with fake frogs and played their traditional mating call.

They kept some still and agitated others to create the desired water effect. Ultimately they found that the bats were over 35 percent more likely to zero in on the frogs surrounded by moving water.

Researchers also discovered that when frogs called from leaf-filled shallow waters, they were less likely to emit ripples and thus safer from attack.