Assessing the diet and trophic niche breadth of an omnivorous fish (Glanidium ribeiroi) in subtropical lotic environments: intraspecific and ontogenic responses to spatial variations

The diet of Glanidium ribeiroi was investigated in lotic stretches downstream from a cascade of reservoirs to determine how it responds to intraspecific and environmental variations. Monthly sampling was performed from 2013 to 2016 at sites including the main channel of the Iguaçu River and tributaries in preserved basins and agricultural land. The diet of individuals in the preserved tributaries was primarily associated with allochthonous...