title: Feeding ecology and trophic comparisons of six shark species in a coastal ecosystem off southern Brazil.
abstract: The diets of six shark species, Sphyrna lewini, Sphyrna zygaena, Carcharhinus obscurus, Carcharhinus limbatus, Rhizoprionodon lalandii and Galeocerdo cuvier, were investigated in a subtropical coastal ecosystem of southern Brazil. Stomach content data were obtained to assess foraging niche segregation and ontogenetic shifts in the diets of these sharks. Five of the shark species off the Paraná coast were ichthyophagous, with the exception of S. zygaena, which was teutophagous. With the exception of G. cuvier, which had a generalist diet, the other five species displayed specialization in their feeding. Ontogenetic shifts were observed in C. obscurus and S. lewini with large individuals consuming elasmobranchs. Owing to the diet overlap between C. obscurus and S. lewini, C. obscurus and C. limbatus and R. lalandii and C. limbatus, future studies on the spatial and temporal distributions of these species are needed to understand the extent of competitive interactions.
authors.affiliation: Universidade Federal do Paraná, Caixa Postal 19020, CEP 81531-980 Curitiba, PR, Brazil; GPIc - Grupo de Pesquisas em Ictiofauna, Museu de História Natural Capão da Imbuia, Rua Prof. Benedito Conceição, 407, 82810-080, Curitiba, PR, Brazil.
authors.forename: H
authors.initials: H
authors.lastname: Bornatowski
authors.forename: R R
authors.initials: RR
authors.lastname: Braga
authors.forename: V
authors.initials: V
authors.lastname: Abilhoa
authors.forename: M F M
authors.initials: MF
authors.lastname: Corrêa
mesh_terms: D000818:Animals; D001938:Brazil; D004032:Diet; D017753:Ecosystem; D020387:Food Chain; D011235:Predatory Behavior; D012754:Sharks / Q000145:classification; D013045:Species Specificity
keywords: Carcharhinidae; Sphyrnidae; apex predators; diet; mesopredators; ontogenetic shifts