Mudflat Fiddler Crab

Smithsonian Institute

Fiddler Crabs can be found from the Gulf of Mexico to South America. These crabs are found most often in soft sand or mudflats, near salt marshes. They will feed on algae, bacteria, fungus and detritus (dead and decaying plant and animal matter). The male has one large and one small claw, but the size of the female claws are equal. The male uses this enlarged claw in an unusual mating ritual during which he positions himself beside a small burrow that he has dug, and moves the claw back and forth (in a fiddling motion) to attract a female. If a female comes close by, the male will then tap the ground with his claw. If receptive, the female will then enter the burrow where they will mate. Their burrows also provide shelter from predators such as herons, egrets and raccoons.