FOOD AND FEEDING HABITS OF A POTENTIAL AQUACULTURE CANDIDATE, THE BLACK NILE CATFISH, BAGRUS BAJAD IN THE GOLINGA RESERVOIR

Abstract

A study was carried out into the food and feeding habits of Bagrus bajad in the Golinga reservoir in the Northern Region of Ghana to determine its various food resources and the major food items eaten and to compare food items in the stomachs of juveniles and adults as well as its feeding habits. Samples were taken in 11hr intervals (0600 and 1700 GMT – morning and evening respectively). The study revealed a wide range of both phytoplankton and zooplankton and other accessory prey items eaten by Bagrus bajad giving an indication that the fish is an omnivore. The juveniles exploited mostly Bacillariophyceae/Diatomophyceae (synedra, 3.68 Index of preponderance, Ip), Miscellaneous invertebrates (nematode worm, 1.26 Ip), Accessory preys (insect parts 0.43 Ip), Protozoans (lacrymaria 0.26 Ip), Miscellaneous insects (leptocella 0.18 Ip) and Chlorophyceae (botryoccoccus, 0.12 Ip) while the adults mainly fed on Bacillariophyceae/ Diatomoophyceae (synedra, 1.95 Ip), Chlorophyceae (botryoccoccus, 0.76 Ip), Miscellaneous invertebrates (nematode worm, 0.51 Ip), Accessory preys (insect parts, 0.28 Ip), Cynophyceae (rivularia, 0.12 Ip) and Desmidiaceae (netrium 0.08 Ip). Food items of juveniles and adults overlapped and percentage index of preponderance indicated diatoms to be the most preferred prey items suggesting that both juveniles and adults exploited similar food items. The ability of Bagrus bajad to feed on a wide range of food resources makes it promising for aquaculture especially in semi-intensive fish farming systems in the Tropics.