Re: Shell Wildlife Photographer of the Year - "song-rings"

It's a great photo, as are the other winning photos.

The "song-rings" are vortex rings, like smoke rings:
    http://en.wikipedia.org/wiki/Vortex_ring

In this case, the vortex becomes visible as the moisture condenses
in the cold air rather than being particles as in smoke.  The short
pulses of sound in a Corn Bunting's call combined with its open
mouth apparently are ideal conditions to create a vortex ring.

If you know how to blow smoke rings, you should also be able to
blow "song-rings" on a still, cold day; I'm looking forward to
winter to try it.  (Anything to end summer...)

-- 
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
   Paul Taylor                           Veni, vidi, tici -
                    I came, I saw, I ticked.
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www.birding-aus.org
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