What is a Ghost Crab?

A ghost crab is a crustacean of the genus Ocypode that dwells on sandy shores in tropical and subtropical regions. The creature is aptly named, as its pale color allows the crab to blend into the sand. The ghost crab, which is usually about 3 inches (about 7.5 centimeters) wide, is known for its distinctive stalked eyes, which allow it to see in any direction. Males can often be identified by horns attached to the end of their eyes. The crab is sometimes enjoyed as a delicacy, and can be eaten raw or broiled.

Possessing a rectangular shaped shell, the crab has 10 jointed legs and is capable of moving forward, sideways, and backward. The fast-moving ghost crab is also able travel about at speeds up to 10 miles (about 16 kilometers) per hour. The creature's watertight external skeleton prevents it from drying out, and also provides support to organs and muscles.

As the crab grows, eventually it will lose or molt its external skeleton. When the external skeleton is ready to come off, a slightly larger new one is ready to take its place. After the external skeleton comes off, it takes a bit for the new one to harden and so the crab is vulnerable during that time.

The ghost crab lives alone in burrows by the water. The burrows may extend approximately 4 feet (about 1.2 meters) deep, which helps keep the creature damp and cool during the day. A male crab typically dwells in a burrow that is identifiable by the neat pile of sand next to the entrance. Females and young crabs are not as neat, and reside in a burrow that has sand scattered in all directions around it. Females are able to find a mate by identifying a male's residence.

The crustaceans are able to communicate with each other through sounds. A ghost crab possesses a special mechanism on its right claw, called a stridulating organ. When the crustacean strokes the stridulating organ against a point at the bottom of its leg, it produces a squeaky noise. This noise may serve as a warning to other crabs to avoid entering a burrow, or may also be used by males to attract females.

At night, the ghost crab sometimes will dig and repair its burrow, and also look for food. Ghost crabs are scavengers, and will comb the beach seeking any plants or animals that washed ashore. The diet of the crab includes snails, clams, baby sea turtles, and lizards.

Ghost crabs are small, sand-colored crustaceans known for their ability to blend into their beach surroundings. They inhabit coastal regions of the Atlantic and Pacific Oceans. According to the World Register of Marine Species, there are over 20 species of ghost crabs, each adapted to life on sandy shores where they dig deep burrows for protection and moisture.

Ghost crabs owe their name to their pale, almost translucent coloration and their nocturnal habits. This camouflaging color helps them avoid predators as they scuttle across the sand, making them seem like fleeting apparitions in the moonlight. Their elusive nature contributes to the 'ghostly' moniker, as they often vanish quickly at the slightest hint of danger.

Ghost crabs are omnivorous scavengers, feeding on a variety of organic material. They consume plant matter, detritus, and carrion, but also actively hunt small animals such as clams, turtle hatchlings, and even other crabs. Their diet is crucial for the beach ecosystem, as they help clean up debris and recycle nutrients, maintaining a balanced environment.

Surviving in the harsh beach environment, ghost crabs have developed several adaptations. They can run swiftly to escape predators, and their burrows, which can be up to four feet deep according to the Smithsonian Marine Station, provide refuge from heat and dryness. They also have special gills that retain moisture, allowing them to breathe air and stay out of water for extended periods.

Yes, ghost crabs can change color to better match their surroundings, a process influenced by their activity and exposure to light. This color change is gradual and can take weeks. It's a survival mechanism that helps them evade predators and is more pronounced in younger crabs, which are more vulnerable to predation.

Ghost crabs play a vital role in coastal ecosystems. As both predators and scavengers, they help control the population of smaller creatures and clean up organic waste. Their burrowing activity aerates the sand, promoting a healthy environment for microorganisms. They are also indicators of beach health, with their presence signifying a relatively undisturbed and balanced habitat.