50 million crabs are invading people (5 photos)

This amazing natural phenomenon occurs once a year on a distant tropical island, located a couple of thousand kilometers from the northwestern coast of Australia.





So, meet the culprit of our today's episode - the Christmas Island red crab (Gecarcoidea natalis). This rather large crab (the shell is more than eleven centimeters wide) is endemic to Christmas Island and another neighboring island.

Despite the fact that it is found on only a couple of islands in the world, this species cannot be called small in number. At least fifty million crabs lived on the island, whose area was only one hundred and thirty-two square kilometers.



Once a year on December 31, they gather with friends for a bath and begin their migration to their breeding site on the coast. The fact is that these crabs are land crabs and live in the tropical forest, not the ocean, but the young are raised the old fashioned way - in salt water.

With the onset of the rainy season, huge crowds of crabs move in a continuous stream, covering distances of several kilometers per day. At this moment, their metabolism changes, and all accumulated reserves are used to get to the sea (exactly like with us in the summer season).

It is noteworthy that people protect them by building transport routes across the roads for them and stopping the movement of cars so as not to crush them.





Male crabs arrive ashore first, set up holes there and wait for their girlfriends. After a short holiday romance, the males return to the forest, and the females remain in the burrows to hatch eggs. When it matures, it is laid in the sea, and the larvae of future crabs immediately hatch from it.

After some time, the babies grow up and, in masses of millions, if not billions, come ashore, and eventually also migrate to the forests.



This spectacle (both the migration of adult crabs and juveniles) looks impressive and attracts tourists every year who dream of seeing it with their own eyes. Alas, this amazing natural phenomenon may soon disappear.

Someone accidentally brought giant yellow ants to the island from the Maldives, which take moving crabs as a threat to their colony and destroy them. In recent years, the number of crabs has fallen by a quarter! And if people cannot come up with anything, then there is a chance that sooner or later the ants will win this “battle of the nations.”