<p>Cliff swallows are flying in the sky with the moon in the background.</p>
<p>Cliff swallows</p>
<ul><li>Keywords: yellowstone national park; wildlife; birds; passiferomes; ynp; yellowstone; yellowstone forever; cliff swallow; moon; spring; cliff swallows; Petrochelidon pyrrhonota; 20180609-jwf-1685</li></ul>
Jacob W. Frank
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