Diet of the freshwater stingray Potamotrygon motoro (Chondrichthyes: Potamotrygonidae) on Marajo Island (Para, Brazil)

The stomach contents of 137 examples of Potamotrygon motoro caught in 3 locations (Muana, Afua and Lake Arari) on Marajo Island were analysed. The values of the Index of Relative Importance (IRI) and its respective percentage (%IRI) were calculated. The level of repletion 1 (1/4 full) was the most representative for both sexes, as well as for immature and mature specimens. Most of the food items found were well-digested. The food items identification indicated the presence of 15 orders, including insects, mollusks, crustaceans, annelids and fish. Differences in diet were observed among the locations studied when comparing %IRI, crustaceans being the most preferred in Afua, fish in Lake Arari and mollusks in Muana.