Cardinal fish

Photo: Erica Callegaro · © all rights reserved

The Mediterranean cardinal fish is a small, red-orange species that forms hovering schools in the dim interiors of caves and overhangs throughout the day, emerging after dark to feed on zooplankton in the open water column. Male cardinal fish are mouthbrooders — the male incubates a clutch of eggs in his oral cavity for several days, going without feeding until the larvae are released. Inside Grotta Azzurra, schools of 50 to 200 cardinal fish hover at mid-water in the chamber, forming one of the cave's most characteristic sights.