ZAP’S FACTS!
REEF LIFE

That white sand beach? A parrotfish probably pooped it.

Parrotfish bite chunks off coral reefs, grind them up, and poop out fine white sand.

2 min read
That white sand beach? A parrotfish probably pooped it.
THE FULL STORY

Parrotfish look like underwater parrots: rainbow-colored, big-eyed, and equipped with a beak-shaped set of fused teeth. They use that beak to bite chunks straight out of coral reefs. They aren’t really after the coral itself - they’re after the tiny algae growing inside.

To get to the algae, parrotfish grind the coral chunks down with another set of teeth deep in their throats. The algae get digested. The pulverized coral - basically very fine white powder - comes out the other end.

A single big parrotfish produces around 700 pounds of this sand every year. Multiply that by a reef full of them, and you get something incredible: most of the soft, brilliant white sand on a Caribbean or Pacific beach started out inside the gut of a parrotfish.

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