For more information on the habitat, vegetation, and weather of the area where I made this observation, please see the journal entry for April 28, 2012 here on iNaturalist. I know this isn't a particularly good picture of the tern, but it was constantly flying around and diving into the water, so I was lucky to get this shot where the black stripe on the top of the head and the long, narrow beak are clear. This bird was about a foot long with a 3 foot wingspan and a forked tail. I observed it diving for food a couple times. It actually dove from a few feet in the air into the water. There did not appear to be any others like it nearby and the only other thing I observed it doing before it flew off was being chased by a gull.