Red crab populations boom as masses are on the move

The population of the famous crabs of Christmas Island is booming wildlife bosses say, as the creature begin their famous migration again.

Parks Australia revealed numbers have more than doubled from 45 million to 100 million over the past few years.

Park bosses released a video of the scarlet creatures' slow sideways march towards the sea, which has begun in the past couple of weeks.

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Every year during the wet season, the creatures head out of their rainforest homes to the sea to spawn.

The males lead the way, followed by the females.

Remarkably, they're guided by the moon.

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After mating, male crabs will make the long journey back to the forest.

The females will release their eggs on the beach before also heading home.

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After that, the tiny red babies will make their very first journey home to the jungle.

Special roadblocks, and even bridges, are installed to protect the crabs.

Christmas Island is 2600 kilometres from Perth, and only 500 kilometres to Jakarta, Indonesia.