Red Land Crab, Gecarcoide natalis Click to enlarge image
Red Land Crab, Gecarcoide natalis Image: DIBPImages
© DIBPImages

Fast Facts

  • Classification
    Species
    natalis
    Genus
    Gecarcoidea
    Family
    Gecarcinidae
    Order
    Decapoda
    Class
    Malacostraca
    Subphylum
    Crustacea
    Phylum
    Arthropoda
    Kingdom
    Animalia
  • Size Range
    Maximum size up to 12 cm
  • View Bio Regions
    Bio Regions
    Christmas Island Province

Introduction

There are an estimated 45 million Red land crabs on Christmas Island.

Identification

A large, red crab with a rounded carapace. Claws are equal in size. Males are usually larger than females. Females have a broader abdomen than males.


Red Land Crab, Gecarcoide natalis
There are an estimated 45 million Red land crabs on Christmas Island. Image: John Tann
© John Tann

Habitat

Rainforest, coastal shore terraces and urban gardens.

Distribution

They are found only on Christmas Island.

Feeding and diet

The land crabs are a key species in the forest ecology. Their diet consists of leaves, fruits, flowers and seedlings and will occasionally eat dead birds and crabs.

Breeding behaviours

Every Oct to Dec they leave the forest on mass and journey to the nearest beach to breed. The timing on the annual migrations is linked to the lunar cycle so that the female crabs can release their eggs into the sea precisely at the turn of the high tide during the last quarter of the moon. The crabs use the same routes from the forest to the coast and back again every year. In some years the streets of Christmas Island are turned into a sea of red with millions of baby land crabs moving into the forests.

Conservation status

Not Listed