Re: Can bats hear humans speaking and would that cause them problems flying?

Hi Eliza,

Bats produce a variety of sounds, including low frequency calls used for 
social communication, mother-infant recognition, mating, distress, 
aggression and other behaviours. These can be heard by humans and 
therefore bats are able to hear human voices as these fall in the same 
range of frequencies.

Bats' echolocation calls are much higher-pitched (20-215 kHz) and may be 
considered part of a 'sixth sense' similar, but separate, to their lower 
frequency hearing. This means that human voices would not interfere with 
their echolocation any more than a strong taste would interfere with our 
sense of sight. Only if a low frequency sound was particularly loud would 
it interfere as bats need their ears for both hearing and echolocation.

Bat echolocation is a complex topic (it was only discoverted in 1938), but 
a a good introduction to bats in general, including identification, is 'A 
Guide to Bats of Britain and Europe' by Wilfried Schober and Eckard 
Grimmberger, Hamlyn Books, 1989. 

I hope that answers your question,

Dr David Hubble, UK