Dieta alimentar da macujana de barba (Johnius dussumieri, Cuvier, in Cuv. & Val., 1830) no estuário dos Bons Sinais, cidade de Quelimane, província da Zambézia, Moçambique

Abstract

The study of fish food biology with stomach content analysis can generate subsidies for a better understanding of the relationships between ichthyofauna and other organisms in the aquatic community, consisting of an important tool in defining strategies for the sustainable management of ecosystems. The present work aimed to study the diet of the Macujana bearded fish, Johnius dussumieri, in the Bons Sinais estuary, Quelimane city, Zambézia province. From 150 specimens of fish harvested between October and December 2018, the items that made up the monthly diet were identified and quantified. The Johnius dissumieri species had a length variation of 5.5 to 11 cm and a weight of 3.6 to 21.6 g. The results showed four food items, namely. The Index of Relative Importance (IRI) was calculated for each item. In 135 stomachs, 4 items were identified (Acetes erythraeus, Thryssa vitrirostri, Hilsa kelee and Penaeus indicus). The category of crustaceans was the most important in the diet of bearded macujana. Among the crustaceans, they were the most important, while the fish were the least important. The relationship between total weight and total length of the Johnius dissumieri species shows isometric growth with Wt = 5, 56*¿2,99.