<p>I was observing this juvenile cliff swallow when it started to vocalize loudly and flap it's wings as an adult cliff swallow flew straight past it - without stopping. This happened several times in the span of about an hour, and I wondered if the adult was actually feeding the juvenile as it passed, even though this seemed to me to be quite impossible because of the speed with which the adult flew passed each time. In real time it looked like a normal flyby.
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The next time the adult flew past, I loosed off a couple of shots.  This image is not a particularly good one, but it clearly shows the beak of the flying adult bird inside the beak of the juvenile, as the adult flew non-stop past the juvenile.  Unfortunately, both birds flew off after this one flyby, so I was unable to try again. What an amazing flying capability.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/32541690@N02">Alan Vernon</a>
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<a href="//commons.wikimedia.org/wiki/Flickr" class="mw-redirect" title="Flickr">Flickr</a>: <a rel="nofollow" class="external text" href="https://www.flickr.com/photos/32541690@N02/3863482752">In-flight and Mid-air feeding of juvenile cliff swallow by an adult</a>