Comparaison de cinq indices alimentaires utilises dans l'analyse des contenus stomacaux

Compound indices are often used in the analysis of fish stomach contents to characterize diet. Five of these indices, combining two or three measures of prey importance: weight, abundance and frequency of occurrence, are mathematically compared in this work. Data from a feeding study of sparid fish show that different indices can produce different results. Four classifications of food, in terms of preferences, are applied to Sparidae, compared and discussed. A new method of classifying the prey of fish into groups is proposed. It characterizes the main items in the diet, whatever feeding index is chosen for the analysis.