Atlantic Parrotfish

Photo: Martin Grimm · CC BY-NC

The Macaronesian parrotfish is the dominant grazer on the basalt reefs of São Miguel and reaches sizes rarely seen further north, with terminal-phase males displaying brilliant red and blue patterning against the dark volcanic substrate. Their constant grazing on encrusting coralline algae produces the fine white sand that accumulates in the islet's sheltered coves. The population at Vila Franca is notably dense due to the marine reserve designation and the abundance of the crustose algae they depend on.