The experiments are "in the pipe" and on the way, Steve.
Bernie
On Mar 14, 2009, at 5:49 PM, Steve Pelikan wrote:
> There's been a fair bit of work done on the effects of man-made
> noises on the singing of birds. Good evidence that some song birds
> shift the frequencies of their songs in the presence of background
> noise that interferes with usual frequencies and some good work
> showing that individual birds sing louder in the presence of a loud
> background noise. That sort of study ---loudness ---is very time
> consuming since to determine the loudness of several sounds
> simultaneously and at a distance is complicated. Finally, there's
> beginning to be some evidence that oscine's learning of songs can be
> influenced (via some sort of sensory masking) by other sounds in the
> environment and that this can lead to rapid adaptation of songs to
> settings with artificial noise.
>
> Most of the studies along these lines that I've seen have treated
> the ambient noise --- of necessity--- rather simplistically (long
> term statistics on amplitude, frequency) either sampled at the time
> that the birds are recorded or at least at the season and locations
> where the birds are recorded.
>
> Rob's suggestion that it would be interesting to look for effects of
> specific sounds (or of sounds with specific properties) is a good
> one. I don't know of any work along these lines. Please let me know
> if you do...
>
> It is often hard to get good spectrograms from ambient (eg binaural)
> recordings so some scheme that records a soundscape at the same time
> that "closeup/high gain" recordings of individual singers is made
> might be required. Or imagine a field with a grid of microphones
> spaced out in it and a (64+?) track recording! One could chart the
> movements of singers in the environment as well as their songs ---
> something I've always been interested in.
>
> The other problem I imagine is that a huge amount of data would be
> required in order to examine the effect of specific sounds on
> singing behaviour unless one were to concentrate on a sound that the
> experimenter introduces. Probably long-term recordings and some
> computer scanning process to isolate relevant samples.
>
> I can easily imagine writing the software and would be interested in
> people's ideas for the recording setup.
>
> More importantly, what do you think would be a good subject
> (Melospiza with different exposures to roadside noises based on
> distance from highways?) and location? But what specific
> (artificial) sounds to focus on? I haven't got a decent hypothesis
> to propose.
>
> All this is great fun to think about as it could well be part of the
> next generation of experiments, it seems.
>
> Cheers!
> Steve P
>
>
>
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