Reproductive Biology of the African Lungfish Protopterus annectens annectens (Owen, 1839) in the Mono River Basin of Benin, West Africa

Abstract

In the Mono River basin, the African lungfish, Protopterus annectens annectens is found in temporary ponds. This species is of great economic interest because of its high contribution to fisheries. As a result, this study aims at documenting some aspects of its biology. A monthly sampling was conducted during the exploitation period (the rainy season, i.e., July through October 2015). A total of 281 females and 215 males bought from local fishermen were used for the study of reproductive biology and to generate a length-weight relationship. The results show that the specimens’ growth is of the negative allometric type in both males and females. Mean sex ratio (1:0.77) favored females and was significantly different from a 1:1 ratio. Size at first sexual maturity was 29.6 and 30.4 cm total length in females and males, respectively. Frequency distribution of ovum diameter is bimodal, suggesting split-spawning during the breeding season. Absolute fecundity ranged from 447 to 1,200 eggs, while relative fecundity ranged from 4 to 9 eggs per gram of body weight.