Fiddler Crab: Uca

Appearance:

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.

Habitat:

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 pellets.

Behavior:

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.

Additional Information:

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