How Can Bats Catch Insects Even on the darkest night?

Bats make sounds that are much too high for us to hear. The sounds travel in invisible waves through the night sky. When the waves strike a flying insect ,the sound bounces back, or echoes. The bat hears this with its huge ears. It's like radar. The method that bats use to pinpoint the position of prey using ultrasonic echoes is called echo location. Because of their high frequency, ultrasonic waves are reflected even from objects as small as and insect. Sound that is audible to humans has long wave lengths that do not bounce back very well from small objects. Bats rely on the reflected ultrasonic waves to navigate and to determine the size, direction, speed and position of their prey. Bats that send out ultrasonic waves from their nose use a narrow beam that sweeps back and forth like a searchlight.