DOI: 10.36347/sajb.2019.v07i01.004

Pages: 18-26

This investigation was carried out in order to know the fitting responses of the reproductive potential of Ethmalosa fimbriata, a heavily exploited fish species in Ebrié lagoon face to anthropogenic pollution. Three sites were prospected, Bietry and Cocody bays in most anthropized area and M’Braté far from city disturbances, the reference site. Results showed that, as abiotic parameters are concerned, pollution was more severe at Biétry and Cocody bays than at M’Braté. Regarding E. fimbriata reproductive parameters, length at first maturity for both males and females were significantly higher at the less disturbed site M’braté (109.71 mm LS for females; 106.97 mm LS for males) than in the most polluted sites Cocody bay (97.53 mm LS for females; 91.36 mm LS for males) and Biétry bay (81.24 mm LS for females; 74.25 mm LS for males). Absolute fecundity revealed that E. fimbriata females were less fertile in the most disturbed locations (3800 and 11683 eggs respectively for Biétry bay and Cocody bay) than in the less polluted site M’Braté (median value = 15262 eggs). Investigations on relationships between some biotic parameters of the fish and environmental variables through canonical analysis showed that the studied reproductive parameters were negatively correlated to abiotic variables such as nitrates, nitrites and phosphates. Ultimately, this study showed that when living environment becomes austere in Ebrié lagoon, E. fimbriata reproduces earlier with a reduced number of offspring.