Length weight relationship, condition factor and stomach contents of Hemichromis bimaculatus, Sarotherodon melanotheron and Chromidotilapia guentheri (Perciformes: Cichlidae) in Eleiyele Lake, Southwestern Nigeria

A.O.O Ikulala,A.A Ayoade

doi:10.15517/rbt.v55i3-4.5970

Abstract

Length-weight relationship (LWR), condition factor (K) and stomach content of three cichlid fishes (Hemichromis bimaculatus, Sarotherodon melanotheron, and Chromidotilapia guentheri) were calculated at Eleiyele reservoir, Nigeria, Africa. The fish were collected monthly from fishermen during the dry season (January-March 2001) and the rainy season (April, May, June 2001). Gill nets of mesh sizes 50-55 mm were used. The LWR had a significant correlation for the three species and the growth exponent (b) for H. bimaculatus indicates a negative allometric growth (S. melanotheron and C. guentheri had isometric growth). Condition factor values were higher than one in the three species, and varied with size and season. Stomach contents revealed that the three species are omnivorous and that diet composition varies seasonally.

Highlights

Cichlids are important resources in the aquatic systems of tropical Africa (Fryer and Iles 1974)
From personal observation in 2001 based on monitoring catch by fishermen in Eleiyele Lake, we found that there are seven species of cichlids including H. bimaculatus (Gill 1862) and S. melanotheron (Ruppell 1852) which were not reported earlier
This paper aims to provide data on Length weight relationship (LWR), condition factor and stomach contents of these

Summary

Introduction

Cichlids are important resources in the aquatic systems of tropical Africa (Fryer and Iles 1974). There is little published work on the biology of fish fauna of Eleiyele Lake and is mainly on juvenile cichlids (Zelibe et al 1990a,b), who reported five cichlid species in the lake. Length weight relationship (LWR) of fishes are important in fisheries biology because they allow the estimation of the average weight of the fish of a given length group by establishing a mathematical relation between the two (Beyer 1987). They are useful for assessing the relative well being of the fish population. The food of fish varies for individual species with age, locality where found and with season

Objectives

Methods

Findings

Conclusion