Video: Christmas Island’s Incredible Red Crab Migration

Australia’s Christmas Island, located south of Indonesia in the Indian Ocean, is named for the day of its discovery in 1643.

But, if you’re familiar with the incredible natural phenomenon that occurs there at this time of year, you may have thought that the island was aptly named for the red sea that covers it each year around Christmas time.

While that is not the case, we are closely watching this natural phenomenon taking place on Christmas Island in honor of the Christmas season.

The start of the rainy season on Christmas Island, which normally falls between October and December, causes the red crabs to begin their migration each year. During this time, tens of millions of red crabs migrate from the dense rainforest to the coast. Males usually begin charging before females, reaching shore in five to seven days. Once there, the males dig burrows in the sand for them and their mate to mate in private. After mating, the males begin their migration back to the rainforest, while the females remain in the burrows for about 12 to 13 days while the eggs develop, according to Parks Australia.

Once again, spurred on by nature, the females emerge from their burrows and head to the water’s edge along with the high tide during the last lunar quarter. There they lay their eggs in the sea, which hatch immediately. Waves and tides wash the young larvae out into the ocean, where they grow for about a month into young crabs, then return to shore. Then they complete the cycle of migrations, marching for about nine days to reach the tropical forest.

Because tens of millions of these crabs migrate at a time, they can become a nuisance to locals, blocking roads, bridges, and just about any surface as they descend toward the shoreline. To protect these crabs, officials have enacted road closures during migration and have even built bridges and “crab crossing” pathways to protect the crabs, according to the Christmas Island Tourism Association.

Needless to say, this migration is one hell of a sight! Take a look below to see these red crabs making their way to shore:

Leave a Comment