Bat sonar: How do bats hear their prey?
It’s British Science Week and this year’s citizen science projects are all about bats! Bat Detective is an audio visual project that asks people to listen to a database of sonograms to identify and classify different bat calls. Find out how you can get involved here, then read on to discover the incredible ultrasonic hearing bats use to find their prey…
Contrary to belief, bats do demonstrate an acute sense of vision, however this is accommodated during daylight conditions. When night falls, these small mammals are more inclined to use their heightened sense of hearing when hunting prey and manoeuvring around habitats, never being at a disadvantage. This is complemented by their incredible biological sonar navigation system.
But how does this work? Well, bats are inclined to emit ultrasonic sounds, with a frequency of between 50,000 and 200,000 vibrations per second, too high-pitched for human ears to comprehend.
These sound are emitted 20 to 30 times each second in all directions, with the bat listening between pulses, scanning for echoes with its head in perpetual motion. Bats separately perceive and process overlapping echo delays, arriving as little as two microseconds apart, that’s an impressive two thousandths of a second. The bat’s own nervous system supports this fined-tuned capability, allowing them to identify echo-reflecting points on an object the width of a pen line on paper, or objects as close together as three-tenths of a millimetre.
Bat ultrasonic sonar system
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