they look cool moving, the audio track is just the random crowd noise
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/8749778@N06">Eric Kilby</a> from USA
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/8749778@N06/3487916315/">Moon Jellies Swimming</a>