On Wed, 06 Jul 2016 09:24:16 -0700, Bret Hess wrote:

Amazing. And the swifts don't even look like they are specially built
for soaring.

I think they're ridge-runners. The only time I've really watched them was
a soaring over a multi-story rock in Turkey - it had been a Hittite fort,
so it was easy to get to the top through its stairways and passages.
There always seemed to be big flock of swifts flying around its top
without much obvious wing flapping going on, so hindsight tells me they
were probably using a mix of ridge lift and thermals off the hot, rocky
slopes.


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martin@ | Martin Gregorie
gregorie. | Essex, UK
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