SOME ASPECTS OF THE BIOLOGY OF HEMISYNODONTIS MEMBRANACEUS (GEOFFREY ST- HILAIRE, 1809) IN ZARIA, KADUNA STATE, NIGERIA

Abstract

Some aspects of the biology of Hemisynodontis membranaceus (Geoffrey St- Hilaire, 1809) in Zaria were examined between the months of May and July, 2006. A total of 134 specimens were observed with the sex ratio of 1:1.23 males to females in all the months together. The mean standard length was 14.05cm while the body weight ranged from 22.8g to 318.5g with a mean of 75.3g. The length- weight relationship indicated positive and high correlation in both males (with 0.8809) and females (with 0.8479) and all the sexes combined (with 0.8269). The fish exhibited isometric growth in both sexes. The condition factor for both males and females indicated that the well-being was high through-out the period of study. The mean condition factor ranged from 2.50 to 2.84. The analysis of the stomach contents indicated that H. membranaceus is an omnivore with algae (which constituted 40.29%), plant material (29.10%) and insects (22.38%) as its main diets. Since H. membranaceus is an omnivore it can be used in large aquarium set-up to feed on mollusc, algae, insects and other aquatic organisms.