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Published: October 26, 2016

Do All Bats Echolocate?

The ability to navigate gracefully in the dark seems like a superpower at first glance.

Many of these flying mammals use echolocation: they emit sonar and then detect the sound waves that return after bouncing off another object. Echolocation is useful for navigation (not running into that tree up ahead) as well as finding food (zeroing in on a tasty moth fluttering nearby).

Bats have a variety of unique tactics for sensing their environments. There's an incredible amount of diversity within this group as a whole: they are the second largest order of mammals, after rodents, with over 1,200 species identified to date—that’s about 20 percent of all mammal species! Many species of bat use echolocation, but they don’t all employ it in the same way. And some bats don’t use sonar at all. Here’s how just a few species of bat use their senses in different ways.

Big brown bat (Eptesicus fuscus)

If you live in Chicago, this is the species of bat you're most likely to spot (especially if you have a bat box). The big brown bat is, in fact, large among American bats, and it's hardy enough to live in most climates throughout the U.S. It uses echolocation in perhaps the most commonly known way: emitting sounds through its mouth to locate prey. It feeds mainly on beetles and is an important predator of insect pests, capturing bugs like moths, flies, and wasps midair.

Golden-crowned flying fox (Acerodon jubatus)

This megabat is the largest in the world by weight, tipping the scale at up to three pounds. It also has enormous eyes, indicating that it relies on good vision to find dinner—which consists of fruit, not bugs. In fact, the golden-crowned flying fox doesn't use echolocation at all. Found only in the Philippines, this wide-eyed bat enjoys the fruit of fig, or Ficus, trees.

Common Asian ghost bat (Megaderma spasma)

Also known as the lesser false vampire bat, its huge, rabbit-like ears are a big clue about its hunting strategy. Known as a "sit-and-wait" predator, it listens for prey to make a noise and then pounces. Found in South and Southeast Asia, the ghost bat uses echolocation as it flies, emitting sonar pulses from its mouth to navigate to its hunting roost. Once there, however, it's all ears. It typically goes after noisy insects like beetles, cicadas, and crickets. Megaderma spasma has a sort of ambush strategy: it forages close to the ground, using its short wings to maneuver among the brush and silently sneak up on its prey.

Enormous-eared horseshoe bat (Rhinolophus philipinensis)

This bat has huge ears in addition to a very elaborate noseleaf—the protruding structure that surrounds its nostrils. The ears and nose work together: instead of emitting sound from its mouth, the enormous-eared horseshoe bat sends out pulses from its nose. A late-night hunter, this bat uses echolocation and excellent hearing to detect the fluttering wings of moths and other insects. With its fine-tuned ability for detection, it has no need for speed, hovering like a butterfly close to the ground.