An Investigation into the Food and Feeding Ecology of Sarotherodon Galilaeus in Oyan Lake, Ogun State, Nigeria

Abstract

An investigation was conducted on the stomach content of Sarotherodon galilaeus in Oyan Lake. Fish species were procured from fishermen using gillnets, cast nets ,traps, hook and line and gura net. Sixty (60) specimens were used for the study. Diet indices such as percentage composition by number and frequency of occurrence methods used to analyze the stomach contents which showed that the food items covered a wide range of diatoms, desmids, blue green algae, green algae, protozoan, detritus and unidentified plants material suggesting that the fish species feeds on both surface water and bottom sediments. The results showed that S. galilaeus is a euryphagous and therefore exploit a wide range of organisms. This makes it an opportunistic feeder. Nonetheless, detritus constituted the most preferred food item eaten by S. galilaeus. Also, filamentous blue green algae were favoured more than diatoms. The preference of filamentous blue green algae over diatoms was consistent.

Key Words: Fish, Food items, Oyan Lake, Sarotherodon galilaeus.