Food and feeding ecology of Tylochromis jentinki (Teleostei: Cichlidae) in Ebrié Lagoon, Ivory Coast, with emphasis on spatial, size and temporal variation in fish diet

Abstract

The diet, gut fullness and reproductive state of Tylochromis jentinki were investigated monthly from February 2004 to January 2006 in Ebrié Lagoon, Ivory Coast. A total of 1850 specimens ranging in size from 75 to 235 mm standard length (SL) were sampled with gillnets in the western part of the lagoon. Diet was described using the Index of Relative Importance (%IRI) and consisted mainly of molluscs (60.2%) and insect larvae (32.1%), the proportions of which varied according to the hydrological season. The diet of T. jentinki changed with size, the juveniles (<97 mm SL) being mostly insectivorous, while subadults (97–122 mm SL) and adults (>122 mm SL) were mainly omnivorous, with larger individuals feeding on larger prey. Periods of maximum food intake, as indicated by gut fullness index, occurred during the spawning months, which coincided with maximum water temperatures.

Keywords: diet, gut fullness, reproduction, spawning

African Journal of Aquatic Science 2011, 36(1): 75–82