Sex Ratio, Fecundity, Gonado-Somatic Index, Length-Weight Relationship and Growth Condition of Sarotherodon melanotheron (Rüppell, 1852) inhabiting Lagos Lagoon, Nigeria

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Adefemi Ajibare
Olajide Loto


This study estimated the sex ratio, fecundity, gonado-somatic index, condition factor and length-weight relationship of Sarotherodon melanotheron inhabiting Lagos Lagoon, Nigeria. A total of 80 fish samples were collected fortnightly with castnets in August 2020, and the sex ratio (3.21:1) was male biased (X2 = 22.05) and revealed a significant deviation from the expected 1:1. The minimum and maximum number of eggs counted in the fish were 251 and 370, respectively, while the mean was 331.37±55.64. The female fish had the highest gonado-somatic index, GSI (3.11%), followed by combined sexes (1.44%) and males (0.82%). The regression equation of the length-weight relationship indicated hypoallometric growth for males (W = 1.58L-0.07) and combined sexes (W = 1.74L-0.50), and hyperallometric growth for females (W = 3.15L-4.42). The condition factor ranged from 1.86 (female) to 2.20 (male), while the K of both sexes was 2.11. The result also revealed that TL (r = 0.975), SL (r = 0.931) and WT (1.000) of the fish were positively and significantly correlated with the fecundity of the fish at p < 0.05. This study therefore established that the study area was conducive for the fish and that their fecundity was directly proportional to their sizes. For conservation and management of S. melanotheron, it is recommended that monitoring of fishing be ensured

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Ajibare , A., & Loto , O. (2023). Sex Ratio, Fecundity, Gonado-Somatic Index, Length-Weight Relationship and Growth Condition of Sarotherodon melanotheron (Rüppell, 1852) inhabiting Lagos Lagoon, Nigeria. Algerian Journal of Biosciences, 4(2), 133–139.


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