Feeding habits of Lutjanus synagris (Teleostei: Lutjanidae) in the Amazon Coast of the Northeast Region of Brazil

Abstract

The feeding habit of lane snapper Lutjanus synagris was analyzed qualitatively and quantitatively, related to seasonality, its ontogenetic development, and the relationship between food and biotic and abiotic conditions on the Amazon Coast of Maranhão, between June 2018 and May 2019. Numerical, gravimetric, and ecological index methods were used to show the relative importance or preference of a category or food item in the diet. The food composition was studied related to the sex, size of the predator and seasonality. Of 359 stomachs sampled, 54 were empty due to regurgitation and presented a vacuity coefficient (Cv%) of 15.04%. In the analysis of diets between the sexes, it was possible to identify a greater participation of fish (30.43%) and Crabs (26.10%) for females, Shrimp (36.23%) and Organic Matter Not Identified (OMNI) (18.84%) in males. The diet showed spatial differences in length distributions. The analysis of stomach contents showed the presence synthetic materials (mesoplastics ranging from 5.0 mm to 2.5 cm) in 5.52% of the samples. The main food items found were from the Brachyura and Caridea species. The results clearly demonstrate that lane snapper prefers benthic prey, presenting a carnivorous and generalist-opportunistic habit. Its diet is also composed of demersal-pelagic species, such as Cephalopods and Teleost fish.