In the present study we analyzed seasonal changes in the diet, feeding behavior and food resource partitioning between juveniles and adults of four characiform species in an Atlantic Rainforest stream of the northern coast of the State of Paraná, Brazil. Samples were collected monthly between September, 1999 and August, 2000 using a variety of capture techniques and underwater observations. In general, full stomach contents were more common in juveniles than in adults. Deuterodon langei Travassos, 1957 was classified as an omnivorous species, with a tendency toward herbivory, Characidium lanei Travassos 1967 was classified as an insectivore, with a tendency toward larvophagy, Hyphessobrycon griemi Hoedeman, 1957 was classified as an omnivore, and Mimagoniates microlepis Steindachner, 1876 was classified as an insectivore, with a predominance of allochtonous insects. Juveniles and adults of all studied species showed low selectivity and high opportunism in their food selection. The high frequency of allochtonous food items in stomach contents underscores the importance of marginal vegetation in their diets, being essential for the integrity of these environments and for the preservation of coastal stream fish communities.
Coastal stream fishes; diet; feeding behavior; food partitioning
