> "Recently I was using Anabat, which puts bat calls into our hearing
> range. I was circled twice by a White-throated Nightjar at night at
> 8.00pm in July 1997. The instrument registered the nightjar giving an
> ultrasonic call. This happened twice.
>
> Does anyone know if an ultrasonic call has ever been noted in
> Australian
> nightjars. Is this a first. And is it an important observation."
>
Glen
I'm also an Anabat user, & the instrument does pick up audible noise as
well as high frequency stuff. Cockatoos play merry hell with the thing
for example. I personally don't know of any ultrasound being recorded
from birds (other than high frequency harmonics of audible sounds).
So:
1. was it really an ultrasonic sound?
2. if so was it a vocalisation, or some kind of skeleto-muscular or
feather "noise" given by the flight action of the bird? (we think
nocturnal birds are silent fliers, but they probably just make sounds
inaudible to human hearing)
3. any chance of you e-mailing me an Anabat file of the sound to look
at (please)?
.. and where does this lucky man live such that he has the pleasure of
WTNs for company in July??!!
Cheers -- Lawrie
===============================================
Lawrie Conole Newsletter Editor
2/45 Virginia Street The Australasian Bat Society
Newtown 3220 ph BH +61 (0)3 9669 9732
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AUSTRALIA ph AH +61 (0)3 5229 4037
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