Red Crab Forest Migration

Red Crab Forest Migration is an original illustration set in Christmas Island, Australia. It lies in the tropics, where the climate is tropical rainforest — hot and wet all year.

Hundreds of vivid red land crabs flow across a wet brown forest floor, seen from ground level. Buttressed trunks and broad leaves close in around them, and the light filtering down is dim and green. The ground is damp and littered.

Why do millions of land crabs march to the sea at once?

Land crabs still have to return to the sea to release their eggs, so the entire population moves at once, timed to a particular moon and tide. That synchrony only survives on an island with no predators able to exploit it. The crabs live in burrows on the forest floor, which requires rainforest wet enough that they never dry out.

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