Our beaches are made of poop

Sand Beach

There are seven quintillion, five hundred quadrillion grains of sand in the world, according to math geniuses. That’s a lot of sand! But where does it all come from? On some beach in the world, a significant portion of that pristine, white, beautiful sand is actually poop.

Yes. Poop. 💩

Don’t worry though! Not human poop or dog poop, but fish poop. Not sure if that is reassuring yet…Hold on.

Specifically, we’re talking about the doody of a very special kind of fish: the parrotfish. Most parrotfish are herbivores. Using their parrot-like beaks, hence the name , and fused-together teeth, they scrape and bite dead coral. Additional teeth in their throats help to break it all down into sand. While diving, you can actually hear them chomping on the corals or see the bite marks they leave on rocks.

Parrotfish

Because parrotfishes don’t have stomachs, their meals pass straight through their body, exploding in a cloud of sand out the backdoor. Also something you can see regularly while diving. Larger parrotfish are like sand factories, producing as much as 400 kilograms of sand per year.

While it may not seem like eating coral would help reefs, these parrotfish actually play an important role in building reef ecosystems. Parrotfish are the gardeners of coral reefs. The sand they poop out is like a filler in the physical structure of the reef, acting like a strong foundation for the coral reef. Also, they eat algae that grow directly on coral, which would smoother the coral if left to grow unchecked.

Of course not every grain of sand is parrotfish poop. The percentage of poop mostly depends on the geographic location of the beach. The sand on a beach in Norway for example, where there are no coral structures and thus no parrotfish will have close to 0% parrotfish poop. The percentage gets higher if you get closer to the equator and if the beach is situated near coral reefs. A study has shown that 85% of the sand produced at Vakkaru Island in the Maldives, was fish poop.

Next time your on a tropical beach somewhere, don’t forget most of the sand you’re stepping on, passed through the guts of a fish. 💩🐠🤓