A male California Sea Lion (Zalophus californianus) displays his not-so-pearly-whites on the dock at Pier 39, San Francisco. Sea Lions have taken over one of the docks there since about 1990; on a given day there can be several hundred of the noisy pinnipeds hanging around. I was setting up for a shot of this one sleeping, and he happened to yawn just when I clicked off the shot. Lucky break :)