To my knowledge, no one has ever made a convincing case that bats
could be identified to species (within a genus, say, like Myotis)
based on echolocation sounds. Distinguishing genera (in eastern US at
least!)is usually fairly easy based on frequency range and general
pattern of sounds. Of course the tropical fauna is much much more
diverse and less well studied.
There's certainly lots of interest in doing this (identification)
since many bats are endangered (way too many) and so there's demand
for methods to survey for presence of endangered species more
efficiently than trapping them and identifying them in hand.
Bats make a lot of other sounds besides echolocation sounds that have
received much less attention (because they're made within and near
roosts for example and so not useful for surveys).
I a small study a while back I looked at distress calls of Little
Brown and Indiana bats ('distress' while in a human's hand being
removed from a net/trap) and found significant differences--- enough
for something like 90% confidence in discrimination between the
species. These calls weren't ultrasonic but rather in the 4-18 kHz
range or so with harmonics into higher frequencies.
I'd be especially interested in learning about other's efforts at
recording bat sounds within or near roosts or in hand. BUT NOTE that
many bats are endangered and can suffer from disturbances, so such
projects should be done very carefully and probably only with
advice/supervision of experts.
Cheers!
Steve P
--- In David Kuhn <>
wrote:
>
> Hi Naturerecordingists, here is an mp3 of a bat I recorded in the
Sierra at 8000 feet, Mkh 20 Mod SASS into SD 702. First 12 sec is as
recorded, from 7 to 11 Khz; then the same sounds dropped in pitch to
700 to 1100 hz, using Audition's Pitch Bender. In spectral view I cut
out all but the target sounds. I think it is quite a beautiful sound,
with a lot of reverb, I had no idea. Is there an authoritative source
for identifying bat species by their sound?
>
> Thanks,
> David
>
>
http://soundshawaiian.com/mp3/Sierra%20bat%20real%20and%20low%20pitch.mp3
> or
> http://tinyurl.com/5mvaf2
>
> =A0>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> David Kuhn
> www.soundshawaiian.com
>
>
> 808 335 0398
> Cell 808 651 8247
> Mail to: PO Box 1018
> Waimea, Kaua'i HI 96796
> <<<<<<<<<<<<<<<<<<<<<<<<<<<<<
>
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