> in some of our work, we found evidence that loudness of a particular
> sound classified as noise didn't have nearly as pronounced an affect
> as the way the noise was perceived (in our case, recorded). Where
> amplitude of the noise had no effect on the biophony, a much softer,
> but more complex class of sound, did. In my post yesterday, I
> described that an F-16 jet flying over a caribou herd with
> afterburners blazing had no aversion effect, but that the "noise" of
> someone approaching the herd on snowshoes most definitely would.
Bernie, this is what drives me crazy about those academic
bioacousticians who want to reduce everything to dBA readings. So far
as I'm concerned, absolute levels of nature sounds are pretty much
meaningless. It's the nature of the sounds that counts.
The challenge for those of us who want to influence the academics is
to develop new types of measurements that reflect what's important.
-Dan Dugan
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