Rich Peet wrote:
> It was also interesting to see how perfectly the vocal range of the
> Virginia Rail slotted between the calls of the American Toads and
> Spring Peepers who were much louder. The rail was easily heard by
> using this technique and I assume that the bird has always commanded
> this frequency slot and did not change its call to this wetland.
Where we have so many species of frogs down here, it's very noticeable
how different frequencies or timing are used to avoid conflicts. It's
interesting in that it shows that many of the species evolved together.
Even within single species there may be a deliberate effort to slot
between others, or in some cases seemingly a deliberate effort to walk
over other's calls. The long calls in toads, for instance are attempts
to outshout competitors. It's like whoever can call longest wins. Though
I've not seen research to back that up.
Certainly one can watch a bird voiced treefrog call and see how he's
focusing on one particular other bird voiced call. They seem to take
turns listening in between.
Walt
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