Feeding habits and habitat use of three sympatric piranha species in the Pantanal wetland of Brazil

Abstract

We investigated the diet and habitat use of sympatric piranha species (Serrasalmus maculatus, S. marginatus, Pygocentrus nattereri) in three rivers and three lagoons of the Miranda River basin in the Southern Pantanal, Brazil. The three species showed differences in size, weight, abundance, and diet between sites; but not in terms of habitat use. Serrasalmus maculatus and P. nattereri were most abundant in rivers and lagoons. The low abundance of S. marginatus could be due to its solitary and territorial behavior. Stomach content analysis of S. maculatus and P. nattereri revealed that vegetal material was the main food item consumed. As for S. marginatus, fish fins and scales were the most frequent food item, a direct consequence of its specialized feeding habit. Differences in diet composition amongst the three sympatric piranha species suggest that competition for food resources does not play an important role in the trophic interactions of these species in the Pantanal. © 2007 by Verlag Dr. Friedrich Pfeil.