Atlantic Ghost Crab

• Its eyes, on movable stalks, give it a 360-degree field of view without having to turn its head.
• It produces sounds by rubbing a rough patch of its claw against its leg, a mechanism called stridulation, to communicate inside the burrow.
• It is one of the most widely used indicators of human impact on beaches: the density of its burrows falls as soon as there is vehicle traffic or mechanical cleaning of the sand.
• It runs at about 4 metres per second, which makes it one of the fastest crustaceans, and it changes direction without braking.
• It is terrestrial but still needs the sea: it moistens its gills by wetting itself at the shoreline or by drawing water from damp ground with bristles on its legs, and the females go down to release their eggs into the water.
• Its eyes sit on long stalks and give it 360-degree vision, with a horizontal band of high resolution adapted to a beach horizon.
• It stridulates by rubbing a file on the inner side of its claw against its leg, producing an audible sound it uses to defend its burrow.
• Its abundance is used as an indicator of beach health: it is very sensitive to vehicle traffic, trampling and light pollution, and its burrows are counted as a measure of tourist impact.
• Light pollution disorients it, just as it does hatchling sea turtles.

Skeleton type

Invertebrate - chitin exoskeleton (crustacean)

Habitat and environment

Dunes and dry sand of the upper beach of the western Atlantic

Sources consulted: Wikipedia (es): Ocypode quadrata