Bats navigate using echolocation, bouncing sounds off objects in their path. The high-pitched squeaks of bats are ultrasonic (the opposite of whale sounds), that is, they are above the human hearing range. Nevertheless, they are loud enough to help the bats home in on their prey. The greater bulldog bat, the loudest among these strange flying mammals, makes a sound that tops 140 decibels to track fish moving underwater.
Some bats do not use their vocal cords to produce calls at all, and instead click their tongue or emit sound from their nostrils. Other bats produce clicks using their wings. Interestingly, the exact process by which bats click with their wings is still debated. It is unclear whether the sound results from the wings clapping together, the bones in the wings snapping, or the wings slapping against the bat’s body.
Picture Credit : Google