Introduction:  What Are Bats?

Bats (Chiroptera)  are mammals that have evolved to fly.  Our interest is mostly in British bats (MicroChiroptera). There are 16 resident species of bat in Britain, making up a third of our land mammal species.   They feed on flying insects especially flies, midges, mosquitoes and gnats; and they avoid predators by hunting just after dusk and sometimes before dawn. (They are 'crepuscular'.)   Bats are warm blooded, so prefer warm conditions, and they hibernate when it is cold. 

Bats are not harmful to humans in any way, so don't worry if a bat flutters past you.  Even if they roost in the loft space of your house they will do no harm, and lots of good in protecting your roof from woodworm! 

Bats are a protected species and it is against the law to disturb them.  If you have concerns about a bat colony in your area contact the bat helpline.

 
There are good reasons for our concern about bats.  In the same way that canaries were once used to detect gas in mines, by monitoring bat populations we can get an early warning of problems in our environment.   Bats are important  as a predator on insects, helping to control their population, and making the countryside a much more pleasant place to be out in!  A roost of our commonest bats, pipistrelles, will eat about three million gnats in a month! They are also lovely inoffensive harmless creatures and our country would be a poorer place without them.

Although their sight is quite good, bats use sonar to help them navigate around obstacles and locate their prey in the dark.  The bat makes a loud noise, at a pitch above our hearing range. (Long eared bats have super sensitive hearing and so can use quieter sounds.) The reflected sound is interpreted by the bat to form a kind of picture of its surroundings.  We can transform the sound from the bat to a lower pitch with a bat detector, so that we can hear it.