Feeding ecology and resource sharing patterns between Stellifer rastrifer (Jordan, 1889) and S. brasiliensis (Schultz, 1945) (Perciformes: Sciaenidae) along the coasts of Parana and Santa Catarina, Brazil

摘要

In this study the diet of Stellifer rastrifer and S.brasiliensis were analysed in order to assess the role of resource partitioning between these congeneric, sympatric and abundant species along the coasts of Parana (25 degrees 5528S; 48 degrees 3335W) and Santa Catarina (26 degrees 2555S; 48 degrees 3446W), in southern Brazil. The stomach contents of 240 S.rastrifer specimens (52-195mm total length) and 167 S.brasiliensis (60-182mm total length) collected by trawl boat in March of 2006, were analysed to assess the influence of sites, day and night periods as well as the size class in their diet composition. Although crustaceans have been the main resources of both species, S.rastrifer consumed pelagic and epibenthic items, whereas S.brasiliensis also used benthic resources. Results of permanova analysis provided significant evidence for food resource partitioning and confirm the role of feeding changes in the function of morphology (species, P=0.001), behaviour (day and night, P=0.024), and ontogeny (size classes, P=0.001), strategies to reduce competition and to maintain the coexistence of these syntopic species.