bat squeals

[galanthus]

Sometimes I can hear a very high pitched squeak when the odd bat flies over. Out of all british species how many are audible to the human ear ? Or does it depend on the person's hearing levels ? Do bat detectors pick up the frequencies we can't hear ?

[nightshade]

There are a few Bats that can be heard by humans, children especially.
our range is 15-20 hz part of Leislers and Noctule calls can be picked up
as well as social calls of some other bats
Ask Us Your Bat Questions
this gives an explanation of a bat detector

[goosey]

Ok nightshade - come clean! Are you on commission for everytime you say bat detector

Back to the matter in hand. My daughter can also hear bats, but I can't.

[nightshade]

Goosey ,it is absolutely magical when those flitting dark shapes get a voice!!
A relatively cheap Heterodyne Detector is a very good guide to species (although
there are still some that you need to count the teeth on as confirmation)
My main aims nowdays are to promote the publics awareness of Bats here in the uk
(and EEC) and help make WAB members aware and knowledgeable so that they can
spread the word
No I get no commission just pleasure

[Bambi]

May I just say Nightshade, that you have succeeded in awakening my interest in bats. Eventhough I've always enjoyed hearing their highpitched noise, then trying to spot the bats making the sound and once spotted, watch them (especially loved watching them fly over water), since I read a few of your post here I've really been interested in bats. I've read up on them over the summer, even went on an organized bat walk and have learnt to appreciate them even more.
So your not only raising the awareness in England, but also in Holland !

[nightshade]

Thank you Bambi I am always pleased at having a convert

[thunder]

If you want to hear bats as they fly, it helps to be young and female! Males and older people usually have less acute hearing and the sensitivity to higher frequencies goes first.

All British bats can produce (reasonably) easily audible sounds as social calls, as nightshade has said, but these are mainly made inside the roosts (which can get very noisy, especially on hot days). Some bats produce social contact calls in flight - some sounds produced by Leisler's sound like the alarm calls of Blackbirds, for example.

henrya