Clockwise from left, a reef in Triton Bay, Indonesia; a spine-cheek anemonefish (Premnas biaculeatus); Utila, Honduras. Photos by Jeff Yonover, Dennis Liberson, CORAL staff

Coral Reefs 101

From microscopic algae that provide energy for reef-building corals to large, predatory fish like sharks, the community that makes up a coral reef is one of the most fascinating, complex, and biologically diverse ecosystems on the planet. Sometimes referred to as “underwater rainforests,” coral reefs constantly bustle with life and activity—in fact, the reef itself is alive, made of tiny coral polyps.