For most of the year, red crabs can be found within Christmas Islands' forests, however, each year they must migrate to the coast to breed. The beginning of the wet season (usually October/November) allows the crabs to increase their activity and stimulates their annual migration. The timing of their migration is also linked to the phases of the moon. During this migration red crabs abandon their burrows and travel to the coast to mate and spawn. This normally requires at least a week, with the male crabs usually arriving before the females. Once on the shore, the male crabs excavate burrows, which they must defend from other males. Mating occurs in or near the burrows. Soon after mating the males return to the forest while the females remain in the burrow for another two weeks to lay their eggs. At the end of the incubation period the females leave their burrows and release their eggs into the ocean.