海洋岛屿 12

And with almost no competition from other native animals,

the crabs' huge size allows them

to make the most of another great coloniser

Something found here in abundance.

Coconuts are one of their favourite foods

It's why they're also called "coconut crabs"

And they've been known to carry them

As far as three miles back to a favourite den.

Robber crabs are perhaps the only animals in the world

able to break into a coconut.

The husk is ripped off by powerful pincers.

Other legs drill through the germinating holes

on the seed itself until the nut finally cracks.

The whole process can take several hours

but the reward is a meal rich in protein.

Robber crabs may rule the land

But they're no masters of the sea.

An adult crab would drown in a few minutes

which raises the question

How did these monsters

get to so many of the South Pacific's most isolated islands?