Millions of Red Crabs Swarm Christmas Island Every Year
Every year, swarms of
Christmas Island red crabs make their annual trek to the sea. Tied to the lunar calendar, the massive migration usually begins during the island's wet season in October or November, when millions of crustaceans travel from the rain forest to seaside breeding grounds to mate.
Why are all of these land crabs making a dash to the sea?
These are Christmas Island red crabs, and their annual trek is tied to the lunar calendar.
When they get to the coast, they mate in time for females to release their eggs ...
precisely when high tide turns between the last quarter and new moon.
When conditions are favorable, these crabs hatch by the millions.
Only to return to do their own moonlight dance.
For more on the story, watch Great Migrations on National Geographic.
