It’s one of the largest migrations in the animal kingdom: millions of crabs get together to mate. It’s a sea of red crabs with millions of legs and claws – and you can see this spectacle in action.

Christmas Island was discovered by a British explorer in 1643, and as you can guess it happened on Christmas Day, hence the name. Its population is around 2000 people, most of whom are of Chinese descent.

Christmas Island is located south of Java (Indonesia) and was placed under the authority of the Australian Commonwealth in 1958, it is an external territory of Australia.

Every year in October and/or November about 150 million red crabs migrate to the sea to mate. In a mass parade that covers the island like a blanket, the crabs take about five days to get from the inlands to the coast.

As soon as this five-day trek commences, the island is transformed into a red sea of crabs. Forests, roads, golf courses and sports fields are run over by the small, red creatures. In a huge, red mass they move across the island, and their trek can take up to 18 days in total.

A red crab up close. Peter McKiernan

After mating the males are the first to move back inland where they feed on fruit. The crabs can grow up to 16 cm. Diving and Snorkelling And if you’re visiting this island anyway…

Diving and snorkling
Besides the crabs, Christmas Island is one of the most beautiful diving and snorkelling spots in the world. Its water is crystal-clear and its unspoiled marine life boasts around 200 kinds of coral, and if you’re lucky you can even encounter a whale shark, one of the red crab’s few natural predators.

More information:

Natural phenomenon