Every year, millions of red crabs leave the rainforest floor of Christmas Island and begin one of nature’s most extraordinary journeys. They do not simply head toward the ocean whenever conditions seem right. Rainfall starts the migration, while the moon and tides help determine when the females must reach the shoreline to release their eggs, as per a report by Christmas Island.
For the crabs, timing matters enormously. A female can carry up to 100,000 eggs, and the journey from the forest to the sea has to happen at precisely the right moment.
