Régimes et comportements alimentaires de quelques poissons des récifs coralliens de Tuléar, Madagascar

Abstract

The diet and feeding behaviour of coral reef fishes living in the inner reef flat have been studied near Tulear, Madagascar. 231 species belonging to 52 families have been observed in this habitat. The diet of the 31 most common and representative species have been studied quantitatively, using a modification of Hureau’s technique. Underwater observations have been conducted both by day and by night. The fish community of the inner reef flat comprises resident populations living permanently in this part of the reef and visiting populations temporarily invading the area at high tide. In both cases, certain species feed only by day while others by night ; some feed equally well at any time, others by contrast feed only at dusk. The diet and feeding habits of the 12 most important fish families are summarized. Three main trophic categories are recognized : herbivores, omnivores and carnivores, each of them beeing in turn subdivided into sub-categories. Broadly speaking, herbivorous and omnivo¬ rous fishes feed only during day time, whereas most of carnivorous fishes hunt by night. Diurnal carnivorous species are adapted for the capture of sheltered or protected preys.