How Do Fringing Reefs Contribute to Sand Production on Beaches?

💡 The Answer

• Parrotfish grazing on coral skeletons grind calcium carbonate into fine sand, which is then excreted.
• A single parrotfish can produce up to 90 kilograms of sand per year, much of which accumulates on adjacent beaches.
• Bioerosion by urchins, sponges, and other organisms also breaks down reef structures into sand-sized particles.
• The white sand of many tropical beaches originates primarily from the erosion of fringing reef material.