Which island in the Indian Ocean is the only natural habitat of the Christmas Island red crab?

Which island in the Indian Ocean is the only natural habitat of the Christmas Island red crab? The canonical answer is Christmas Island.

The Christmas Island red crab, Gecarcoidea natalis, is a land crab endemic to the Christmas Island region. Christmas Island supports its largest and best-known population, with millions of adults inhabiting the island’s tropical forests.

Each year, the crabs undertake a spectacular migration from the forest to the coast to reproduce. Females release their eggs into the sea, and the larvae remain marine for several weeks before returning as young crabs.

The species is a keystone part of Christmas Island’s ecosystem. It consumes fallen leaves, fruit, flowers, seedlings, and carrion, helping shape the forest floor. A smaller natural population is also recognized on the Cocos (Keeling) Islands.