Bats See with Their Ears

Bats actually "see" prey with their ears. Through the somewhat complicated process of echolocation, a bat learns from echoes how big its prey is, how fast it is moving and in which direction it is going.

As a bat approaches its prey it increases the number of signals it produces fixing it precisely in the surrounding landscape.

A bat can detect prey, follow its protective evasive movements and catch in less than one second! Scientists blocked bats' ears, and found they crashed into objects while flying in the dark and were unable to catch prey.

The puzzle was unraveled in the 1930's when Harvard University researchers found that bats emitted high frequency sounds that bounced off objects and returned to the bats as echoes. Scientists labeled this ability as "echolocation."

Many bats cannot locate objects more than 10 to 15 feet away from them. Some species have to be closer than that.

Between the emission of a pulse signal and the reception of a returning echo, just six-one thousandths of a second passes.

A bat thinks very quickly in just under a second. It locates its prey, decides if it is edible, tracks the creature's evasive moves, and then catches it. All of this takes just one second. Once a bat locks onto to the exact location of an insect, it rarely escapes being caught. Some moths are able to pick up on the pulses of a bat and begin evasive moves, while others actually send out signals of their own that act as jamming devices to bats' echolocation.

While roosting bats make notices that are detectable by the human ear. We cannot hear the ultrasonic sounds of echolocation. Roosting bats peeps and squeals.

Other creatures that use ultrasonic sounds to help them survive include whales,dolphins, shrews, moths, grasshoppers, crickets and cicadas.

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