Studies on the diet of Rastrineobola argentea were conducted between
August 2014 and March 2015 in the Kenyan waters of Lake Victoria. Stomach
contents of 1154 specimens collected from commercial fishers and experimental
seining were analyzed. Juveniles of R. argentea under 30 mm SL fed almost
exclusively on zooplanktons, while adult fish larger than 40 mm SL preferred
insects. Changes in diet require morphological and physiological changes which
are not yet well developed in young fish, thus, they can easily digest
zooplankton that also satisfy their demand for protein.Diel feeding regime
suggested that R. argentea is a visual feeder. There was spatial variation in
diet composition within the studiedstations. Strauss Linear Index of food
selection showed that R. argentea preferred cyclopoida, Daphnia sp and
Brachionus sp(positive values). However, calanoida, Bosmina sp and Keratella sp
were avoided in most stations (negative values). The change in diet among the
stations could be attributed to the environmental changes occurring in Lake
Victoria associated with changes in composition and abundance of zooplankton
community. The information on the ecology of R. argentea are of considerable
ecological importance. - See more at:
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