Sea otter?? See otter????

While I was down by the water, a sudden movement caught my eyes.  A small, brown mammal ran in front of my boots.  It did not appear to be either a squirrel or chipmunk.  I thought it might be a beaver, but the tail was round and not flat.  I wonder if it was an otter.  I took the following picture.  The small patch of brown in the middle (between the green leaves and the gray rock) is the creature.  See if you can find it . . . .  See if you can identify it . . . .