All the birds we saw as we began walking out the spit at Ft. Flagler were a long way offshore, but as we got about halfway out the spit I noticed that the rocks on the shore seemed to be moving. Turned out they were what is quickly becoming one of my favorite birds at Flagler, a Sanderlings in winter plumage.

A little further up the spit, they were joined by a large flock of Dunlin foraging as a single flock, unlike the Sanderlings that darted here, there, and a little of everywhere.

The Dunlins not only foraged as a single flock, they periodically all took off and flew back and forth up the shoreline,

Only to land a few feet away from where they started.

… and a real ending. But that’s okay because there are a few more to come in the (near) future.
Pop star Moby published a book of his photography, and it has a lot of pictures of crowds. I’m paraphrasing, but he commented that he likes crowds because you can think of a crowd as one entity, with a personality of its own, even though it’s made up of hundreds or thousands of individuals.
I imagine a flock of birds and a crowd of people are the same in that way.
They do seem to have a “single mind” but I’ve never been able to figure it out.