Food and Feeding Habits of Schilbe mystus from the Lower River Benue at Makurdi

Abstract

A study on food and feeding habit of Schilbe mystus in the Lower River Benue at Makurdi, was carried out. Two hundred (200) fish samples were examined for stomach content. The body weight (WT), Total Length (TL) and Standard Length (SL) of each specimen was measured to the nearest gram and centimeters using a weighing balance and tape/ meter rule on a dissection board. The length weight relationship was determined by plotting a graph of Length-Weight. The gut for each fish specimen was cut open using a pair of scissors and scrapped onto a grease-free glass slide and examined for stomach contents and viewed microscopically. Result revealed the following food items; insects (64.42%), fish (20.2%), crustaceans (10.6%), detritus (15.4%) and unidentified materials (50.1%). Insects recorded the highest percentage in the stomach both on frequency of occurrence and gastro-somatic index methods while crustacean recorded the least percentage in both frequency of occurrence and gastro-somatic index. Smaller fish within the length range of 10.1-15.0 cm weighing between 0.1- 50 g were more of empty stomach (65.0% and 67.2%) than those with food (35.0% and 32.8%). Fish within the length range of 25.1- 30.0cm and 35.1- 40.0cm weighing 100.1- 200.0g and 200.1- 350.0g were found to contain stomach with full diet components, particularly insects, fish and crustaceans. Length weight relationship (LWR) and Length- length relationship (LLR) indicated that values of correlation coefficient (r2) are highly correlated, r2 > 0.7 and r2 > 0.8 at p < 0.05. Therefore, Schilbe mystus tropical features in the lower River Benue showed that it is a carnivorous and the pray type is influenced by their availability. This study provides data for the better understanding of the biology and ecology of Schilbe mystus in the Benue River which will also contribute to the development of aquaculture industry.