Bumphead Parrotfish

Photo: Mark Rosenstein · CC BY-NC

Schools of bumphead parrotfish visit the shallow crest at dawn, using their calcified foreheads to ram and excavate coral skeletons and producing audible crunching sounds underwater. Each fish processes several kilograms of coral per day, excreting fine white sand that accumulates in the channels between terraces. Their presence signals a reef ecosystem with sufficient biomass to support large, long-lived herbivores, and Aka's protected status has allowed this vulnerable species to persist in unusual numbers.