Bocas Species Database

Habitat: This species will be found in partly shaded mud, near mouths of streams and usually among or near mangroves.   Distribution: This crab species has been reported from the Western Atlantic Ocean.   Natural History Notes: The activity of fiddler crabs is related to the tides. At low tides, the crabs stay in their burrows, but during the low tides, the crabs open their burrow and reach the surface to feed, clean their burrow and to undergo courtship.   Characteristics: The carapace of this species can reach 1.7 cm long. The color pattern consists of a dull brown carapace, with a yellowish or reddish major claw with whitish fingers. We can distinguish small tubercules on the outer surface of the claw. Fiddler crabs (genus Uca) present easily recognizable sexual dimorphism. The males have one very large claw (major claw) that is used to undergo a characteristic wave to attract females or to defend its territory. The females do not posess such a large claw. Also, the males usually have more conspicuous colors and they are larger than the females.