Aspects of the feeding ecology of three species of Pseudotolithus (Sciaenidae) in the inshore waters of southeastern Nigeria, east of the Niger Delta, Nigeria

Abstract

Aspects of the feeding ecology of three species of Pseudotolithus (P. elongatus, P. senegalensis and P. typus) in the inshore waters of southeastern Nigeria were investigated for 12 months because of the importance of the croakers in artisanal catches. The major dietary components of the three species were crustaceans (shrimps) and juvenile fish. The food composition of P. elongatus did not show any variation with sex and season except plant materials recorded only during the rainy season. Ontogenic variation in feeding did not exhibit any definite pattern in P. elongatus. Feeding activity was greater in the dry than wet season and in females than males except at Qua Iboe River estuary where the reverse was the case. The diet composition of the three species of Pseudotolithus portray them as specialised feeders subsisting on similar food sources with low number of dietary items. Such high trophic specialization is attributed to the rich supply of autochthonous dietary items with the disadvantage of encouraging competition, which they overcome by expanding their dietary options.


Key Words: Feeding ecology, Pseudotolithus, Sciaenidae, Nigeria


Journal of Aquatic Sciences Vol.19(2) 2004: 51-58