Fiddler crabs is what these are. The body is about 3/4 inch wide, and fishermen use them for bait if they move fast enough to catch them. Shooting a macro would be impossible since they're very shy and move quickly, so I shot these at full zoom (~1000 mm effective FL) from about 55 feet distance, from the pier down to the mud flat. Still, it was a very heavy crop, so the resolution isn't good. This crab was moving its claw to the up and down positions alternatively a number of times, as though it were digging a hole. I wish it luck, since a tropical storm has moved in over Charleston and is sitting on top of us, without moving all day. It's going to be extra wet in the crab's house. Canon SX720, f6.9, 1/100 handheld, ISO 80. Canon SX720, f6.9, 1/100 handheld, ISO 80.