Dieta e atividade alimentar de Pimelodus maculatus (Osteichthyes, Pimelodidae) no Rio Piracicaba (Estado de São Paulo, Brasil) í O efeito da sazonalidade

Abstract

The study describes the effect of seasonality on the diet and feeding activity of Pimelodus maculatus in the Piracicaba River (State of São Paulo, Brazil). The stomach contents of individuals caught along the four seasons of the year (n=241) were analyzed and the Stomach Fullness Index of each specimen was calculated. The results indicate that P. maculatus is an omnivorous and opportunist species, which consumes mainly aquatic insects during the whole year. However, it presents seasonal diet shifts, due to the oscillation of the secondary items importance, which is probably the result of the distinct availabilities of food along the seasons. Moreover, its highest feeding activity occurs during the autumn and the lowest one, in the coldest months, i.e., in winter.