Aspects of life history pattern of Hemichromis fasciatus Peters, 1857 in Okpara Stream, Northen Benin, West Africa

Abstract

The piscivorous cichlid Hemichromis fasciatus dominated the Okpara Stream of Oueme River in Benin, and numerically made 29.49% of the fish community. Some aspects of the reproductive biology of this a fresh/ brackish water cichlid were examined to evaluate the spawning patterns and establishment of the species in Okpara Stream. Hemichromis fasciatus individuals were sampled monthly during 18 months from December 2015 to May 2017 with seine, castnets, gillnets, hooks and traps. Among the 2,818 individuals sampled, 55.43% were females and 37.33% were males with a sex-ratio of 1 male for 1.49 female. The species showed lowfecundities ranging between 113 and 1,716 oocytes. Length at first sexual maturity (L50) in Okpara Stream were reduced, 9.22 TL-cm and 10.95 TLcm for females and males, respectively, indicating an early maturation. The ovarian structrure give evidence of multiple spawning and the species reproduces all seasons. In Okpara Stream, Hemichromis fasciatus exhibited a life history strategy betwen “r” and “K” selection, yet, close to “r” selection. Because the length at first capture (Lc50 = 8.78 cm) is lower than sizes at first sexual maturity, stocks of spawners could be reduced and leading to low recruitment.