Fiddler Crab: Uca
Ever chance upon a troop of fiddler crabs marching through the
mud in a salt marsh or mangrove forest? The male fiddlers were
probably the most obvious - they have one oversized claw that
resembles a fiddle. The claw is waved around to attract females
during courtship and is used as a defense against other males.
Fiddler crabs dig burrows about a foot deep in the sand close to
the water's edge. They retreat to these holes when alarmed or when
the tide comes in. The opening is plugged with sand or mud to keep
out the water. As they maintain their sandy homes or strain clumps
of sand through specialized mouthparts to sustain their diet of
algae and decomposed matter, they leave behind conspicuous sand
The thumbnail-sized fiddler crabs are a favorite food of snook,
redfish, ibis, yellow-crowned night herons, raccoons, foxes and a
host of other predators. Though not rare or endangered, fiddler
crabs are a vital part of the coastal food chain.