Are bats audible?

Alliandre

I heard some high pitched chirping noises last night and I saw something flying around (didn't get a good look - it was moving too fast) which I assume was a bat. I didn't think that a bats echolocation would be audible to humans though. Could it have been something else?

Alun

The echolocation sounds of the commonest species of bats in Ireland wouldn't be audible, no, as they're in the range of 45-55kHz, well outside of any human's hearing. There are bat species that drop down into the low 20's, but I'm not sure if they're present in Ireland, and you'd have to have pretty extraordinary hearing to be able to hear them anyway. Most people's hearing starts to drop off after about 16kHz with the top limit at around 20kHz, and gets worse as you get older.

Bats also make what are called 'social calls' that they use to communicate amongst themselves, but these will generally only be used amongst themselves in the roost or as they're just entering or leaving the roost, so not as they're flying around in your garden. These are audible to humans though.

A possibility according to this is that you could be hearing swifts. is that a possibility?

Alliandre

Well I don't think it was a swift (this was around 2am - unless swifts are nocturnal?) and the call sounds different. It was a very brief chirp and it wasn't very loud. I suppose it sounded a little like a grasshopper (though shorter and more high pitched), but that wouldn't expain the fact that I saw something flying around. Unless it was both.

Nerin

I've sat watching bats before and heard squeaking noises, no idea what species. Although what you said about social noises could be true,because both areas were below or close to a roost.

Half-cocked

You can hear some Irish bat species but the older you get, the less likely you are to be able to.

Rainbowsend

We have always had bats flying round the garden and I have always been able to hear them, in fact you would hear them before you see them, just a little high pitched squeak, but it is definitely bats.

sesswhat

The social chirping of Pipistrelles can certainly be heard by children and by some adults (no longer by me though).

An electronic bat detector can be used to convert the echolocation calls to a frequency range that can easily be heard by humans.

SeaFields

I do a lot of fishing at night on rivers and can hear the bats chirps around me. Never occurred me to ask the other anglers around me if can they hear them too...

mathepac

I've always been able to hear "bat noise" of some kind. It's unlike birds chirping to my ear and sounds more metallic and less musical. I was out in the back-garden last night with a good few bats chirping around me, wreaking havoc on the midges, flies, moths, etc.

wgsten

SeaFields wrote: »

I do a lot of fishing at night on rivers and can hear the bats chirps around me. Never occurred me to ask the other anglers around me if can they hear them too...

Likewise i fish a lot of the time at night and i have always heard the high pitched noise the bats make. I done a little research into what bats were feeding over the rivers at night and i found them to be Daubenton's bats. As to these been the only bats audible to the human ear i can only leave that for someone else to enlighten me.
wgsten
http://www.irishflyfisher.ie/

Alun

If they're flying low over the surface of the water and feeding of flies and bugs that are just above the water surface they're definitely Daubenton's bats.

You'll not hear their echo location sounds either, they're at much too high a frequency at 45kHz, but you might hear their social calls. As I mentioned above I was always under the impression they didn't really use these when in normal flight, and only when they're in or close to their roosts, but maybe I'm wrong. I've never heard them myself but then my hearing is completely shot after a misspent youth and lots of heavy rock music, so it's good job I have a bat detector

There are species that have lower echo location frequencies such as Leisler's (25kHz) and Noctule (20-25kHz) and these frequencies can vary a little depending on where they're hunting and the individual bat, with some maybe getting down as low as 18kHz, but that's still pretty high for most people's ears.

Connacht

I stood at the entrance to a cave with bats within the other day in France and heard them as clear as you like.
Can't remember which species, but it was the one with the extra large ears.

John mac

I can hear bats. always could.

I had a mouse scarer (the one you plug in and emits high pitch ) had to get rid of it as it was driving me mad.