Dietary composition and trophic level of Hypanus marianae (Myliobatiformes: Dasyatidae), captured off Pernambuco coast, Brazil
Queiroz, Aristóteles P.N.
Araújo, Maria L.G.
Lessa, Rosângela P.T.
Hypanus marianae, a stingray endemic to Brazil, inhabits coastal coral reef areas occurring in the landings of artisanal fisheries. The present study aimed to characterize the diet of this species captured off Pernambuco. We obtained 77 stomachs with contents: 52.27% female, 47.72% male. DW ranged from 15 to 37.80 cm mean of 26.53 ± 4.82 cm. Four higher taxonomic prey categories were identified: Arthropoda, Annelida, Chordata and Sipuncula. The most important item in the diet was Polychaeta (40.65% IRI), followed by Leptochela serratorbita (30.35% IRI), suborder Dendrobranchiata (10.18% IRI), order Isopoda (4.19% IRI), and Meiosquilla schmitti (3.56% IRI). H. marianae displays specialized predatory habit (BA = 0.06) primarily based on shrimps (42.36% IRI) and polychaetes (40.65% IRI). There was no significant difference in the diet by sex or in sexual development stages. However, neonates fed on decapods crustaceans (70.68%) and polychaetes (17.09%). For immatures, decapod crustaceans (69.5%) and polychaetes (25.86%) made up most of their diet. The adults feed mainly on polychaetes (62.79%) and crustacean decapods (30.47%), with a slight increase of fish (5.46%). The trophic level (TL) estimated was based on stomach content analysis was 3.66 and estimated on the analysis of stable isotopes being 3.29, which classified the species as a mesopredator.