FIDDLER CRABS
OCYPODIDAE
Atlantic Ghost Crab
Ocypode quadrata
Size
Carapace up to 5cm. 

Description
:
Body and legs pale/ sand coloured. They have a quadrate carapace. Claws sharp and
whitish. Black, clubbed, stalked eyes. Stands erect on tips of walking legs. Males are generally larger than females.

Ecology
Fast running. Builds tunnels just above the high-tide line. Burrows are up to 1.3 m and can be closed off with sand during hot periods. Nocturnal omnivore  and scavenger,  eating bivalves, insects, plant material, detritus, and even other crabs. They must return to water periodically to moisten their gills, and when larvae must be released into the sea.
O.quadrata can produce a variety of sounds by striking the ground with the claw, by stridulation with the legs, and an incompletely explained "bubbling sound". Males compete in a heavily ritualised manner which reduces the need for physical contact.

Life Cycle
Mating can occur throughout the year. Unlike other crab species, ghost crabs can mate even when the female’s integument is hard, which means that they can mate anytime after sexual maturation. This is an adaptation to terrestrial life. Mating occurs while both the male and the female have a hard shell. Usually mating will occur somewhere in or near the burrow of the male. Often copulatory plugs are found in ghost crabs; the male will release a seminal fluid along with his sperm that will become hard and prevent rival sperm from reaching the female’s ova
After hatching from an egg, Ocypode quadrata has five zoea stages and one megalopa stage. The megalopa stage requires at least 35 days for development. The larvae develop in saline water. The megalopa stage of O. quadrata is one of the largest of the brachyuran crabs. Metamorphosis into the first crab stage takes place at the surf-beach interface.
Females reach sexual maturity when their carapace is larger than 25 mm. Males reach sexual maturity when their carapace is larger than 24 mm. This usually occurs when they are about a year old.
    Ecological Descriptors
Habitat Size (cm) Diet Behaviour Sex 
SupLit 5
(carapace)
Omn, Sca, Noct I F
Atlantic Ghost Crab
217
Atlantic Ghost Crab
403