Feeding habits of Centropomus undecimalis (Actinopterygii, Centropomidae) in the Parnaíba river delta, Piauí, Brazil / Alimentação do Centropomus undecimalis (Actinopterygii, Centropomidae) no estuário do delta do rio Parnaíba, Piauí, Brasil

Abstract

The objective of this work was to evaluate the feeding of Centropomus undecimalis in the estuary of the Parnaíba river delta, with emphasis on diet composition during seasonal variations between dry and rainy seasons. The samples were obtained from artisanal fishing with gillnets, from June 2014 -July 2015. The individuals were measured, weighed and dissected to remove the stomachs. The fish diet was analyzed using the methods: Gravimetric, Frequency of Occurrence, Dominance of the item and Food Index. One hundred and seven stomachs were sampled, of which 72% had food content. The diet consisted of eight Teleostei fish and crustaceans during the dry and rainy seasons, as well as organic material of remains, sediments and plastic. Similarities were observed in stomach contents, indicating specialization, but at individual scale (inter-phenotypic). Thus, it may not occur for the entire population. The analyses of the diet allowed to confirm that C. undecimalis is a carnivorous species for the food chain of the estuary of the Parnaíba River delta, and the diet varies according to prey abundance in the environment.