Crabs

The world’s largest land crab, the robber crab (Birgus latro) can weigh more than 4 kg and measure up to a metre across.

They are sometimes observed within the forest on North Keeling Island, but were probably more abundant prior to hunting by Cocos-Malay people.

Also known as coconut crabs, these gentle giants forage on the forest floor, feeding on fruits, seeds, animal carcasses and the pith of fallen trees.

Hermit crabs

Three species of hermit crab appear in large numbers. They are the red hermit crab (Coenobita perlatus), purple hermit crab (Coenobita brevimanus) and tawny hermit crab (Coenobita rugosus).

These little creatures only grow to a few centimetres and have a soft abdomen that they protect by living in an empty seashell. They need to keep changing shells as they grow, often trying on several different shells to find the one that fits best.

Hermit crabs take refuge under logs and shrubs during the day, venturing out at night to scavenge on the forest floor and beach.

Ghost crabs

There’s nothing spooky about these shy crabs, which will scuttle quickly into their burrow or the sea when disturbed.

Ghost crabs are named after their nocturnal habits and pale colouring, which helps them hide in the sand.

Horn-eyed ghost crabs (Ocypode ceratophthalmus) are common on the north-western beaches of North Keeling Island, and can be easily recognised by the long stalks protruding from the top of their eyes.

Other crabs

The Christmas Island red crab (Gecarcoidea natalis) is common on the forest floor of the island, as is the yellow nipper (Geograpsus crinipes) and little nipper (Geograpsus grayi).

The purple crab (Cardisoma carnifex) is abundant, particularly in the saltmarsh and on the fringes of the lagoon.

Long-legged grapsus crabs (Grapsus tenuicrustatus​) can regularly be seen rock-hopping on rugged sections of the coast.