On Christmas Island, red crabs have started their migration. They roam the roads and forests and offer a surprising spectacle.
The red tide has returned to Christmas Island (Australia). This weekend, millions of red crabs (gecarcoidea natalis) rushed to the Indian Ocean for their annual migration. Each year, these crustaceans emerge from the forest and head to the Indian Ocean to breed, swarming through roads, streams, rocks and beaches.
The bigger and stronger, the males, arrive on the shore before the females, a period of time that allows them to dig a burrow to accommodate them. Once the females are fertilized, the males leave the shore to begin the return journey to the humid forests of Christmas Island. But for females, the adventure continues in the burrow. In the dark, they incubate for twelve to thirteen days more than 100,000 eggs and await the signal of the final stage of their migration: low tides and a waning moon. Once these conditions are met, they rush to the ocean to deposit their offspring. If the winds and luck are on their side, a tide of baby crabs will return to the beach.
With red crab migration in full swing on Christmas Island 🏝️, the crabs are turning up everywhere, including at the door of an office block 😮!
Our staff have been out managing traffic 🚦, raking crabs off roads 🛣️ and providing updates to the community on road closures 🚧. pic.twitter.com/nuYQmNcRST
— Parks Australia (@Parks_Australia) November 15, 2021
The migration of red crabs considerably disrupts the daily life of the inhabitants of the island, to such an extent that urban developments have been installed to facilitate the marathon of the animals, such as bridges over roads. However, the species is threatened by a predator from Asia, the yellow ant. anoplolepis gracilipes.