Fecundity of Sarotherodon galilaeus (Pisces: Cichlidae) in the Opa reservoir, Ile-Ife, Nigeria

The fish Sarotherodon galilaeus was collected in Opa reservoir, Obafemi Awolowo University, Ile-Ife, Nigeria. Sampling began in January, 1992 and extended until March, 1994. The fishing methods employed for collecting the 853 specimens were gillnetting and castnetting. Sex ratio was approximately 1:1 (male: female). Length at maturity was 12.5 cm (males) and 11.7 cm (females). The fecundity was 1 048 ± 785 (604-2173, n= 117) with an egg diameter of 2.49 ± 1.81 (1.0 - 4.5, n = 117) mm. The gonado-somatic index was 0.33 ± 0.21 (0.09 - 1.34, n = 275) (males) and 1.88 ± 1.01 (0.33 - 6.19, n = 282) (females). The species breeds year-round (mature specimens occurred in samples collected throughout the 27-month study period). This fish is a biparental mouth booder