ZAP’S FACTS!
REEF LIFE

Sea cucumbers throw their own guts at predators.

When threatened, they fire their organs out their backsides - and grow new ones.

2 min read
Sea cucumbers throw their own guts at predators.
THE FULL STORY

A sea cucumber looks like a fat slug lying on the seabed. Boring. Squishy. Easy snack, right? Wrong. When something attacks one, the sea cucumber’s response is one of the strangest defenses in the ocean.

Through its rear end, the sea cucumber forcibly shoots out a bunch of its own internal organs - sticky strands called Cuvierian tubules, which expand on contact with water and tangle the predator in a horrible toxic mess. Some species shoot whole parts of the gut. The attacker stops attacking, busy trying to clean itself off, and the sea cucumber slowly crawls away.

Then comes the really impressive bit: the sea cucumber regrows the organs it ejected, usually within a few weeks. To it, this is just a normal escape strategy. To anything trying to eat it, it’s gross enough to never try again.

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