On Fri, Dec 05, 2008 at 06:05:37AM -0800, Rob Geraghty wrote:
> I listened again to the original and it still sounds like a crested
> pigeon to me. I happened to be standing near one today and it
> produced a very similar call. Not the rapidly repeated call of an
> excited male, but a single up-down "woo" with a long gap. But as
> Peter said previously, the microphone used wasn't ideal and there's
> a lot of background noise, so it's hard to be sure.
Peter's call does have the same up-down "inverted U" frequency modulation
as the (usual) Crested Pigeon "woo" and the length isn't too different.
but its frequency is much higher.
Peter's call's dominant frequency goes from 1.1kHz to 1.3kHz.
The Crested Pigeon on the BOCA tapes goes from about 200Hz to 450Hz.
Musicians would say its more than octave lower. So it t might be a
different Crested Pigeon call, but its not the typical "woo".
There is free software available to analyze bird (and other) calls,
that runs on windows/mac/linux:
http://www.birds.cornell.edu/brp/raven/RavenOverview.html
and a pleasant intro in Kroodsma's "Singing Life of Birds" which is not
too expensive bought overseas (see bookfinder.com).
Andrew
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