Quelques aspects de la biologie de la reproduction de Schilbe multitaeniatus (Siluriformes, Schilbeidae) de la rivière Rembo Bongo (Gabon)
Some aspects of the reproductive biology of Schilbe multitaeniatus (Siluriform, Schilbeidae) from Rembo Bongo River in Gabon
To sustainably manage Schilbe multitaeniatus (Pellegrin, 1913) and set up its fish farming, a study of some aspects of its reproductive biology was conducted in the river Rembo Bongo in Gabon, from July 2010 to June 2011. Experimental fishing was conducted in two sites (Mafoumi and Moanda) using gill nets. Results showed that the sex-ratio was in favour of females (χ² = 17.2; p < 0.0001). The size at first maturity, L50, was 22.7 cm in males and 26.3 cm in females. Males and females are all mature from 33 cm and 35 cm (L100) onwards, respectively. Spawning is unique in the year from November to February, with a peak in December, during the short rainy season. Average absolute fecundity (Fa) was 29,880 (± 26,527) eggs and relative fecundity (Fr) average was 139.6 (± 97.33) oocytes/g. The average diameter of the oocyte was 0.6 (± 0.12) mm.