Patterns and partitioning of food resources by elasmobranchs in southern Brazil

Our study sought to analyze patterns and overlap in prey items consumed by elasmobranch species in southern Brazil through a complex network analysis. We hypothesized that species with the same habitat use would show greater trophic niche overlap and lower diet specialization than species with different habitat use. We conducted a literature survey of the species recorded in southern Brazil and analyzed publications with quantitative data on the diet of each species. We found records of 103 species in the region, of which 58 had their diets analyzed and had quantitative data to contribute to this analysis. The results suggest nested diet patterns in this community. Nestedness may arise for different reasons, and suggests that species might be balancing their high feeding niche overlap through compensatory mechanisms. There are no prior records of such a pattern in elasmobranch communities, which brings to light important information about their feeding niche. Data on prey consumption and temporal and spatial patterns of elasmobranch feeding may yield further insight into how these species are interacting in the environment and assist the investigation of the processes that shaped the current community’s trophic structure.