Growth and reproduction of the gilthead seabream Sparus aurata in Mellah lagoon (north-eastern Algeria)

Gilthead seabream Sparus aurata (L.), a protandrous hermaphrodite, was caught in Mellah lagoon (Algeria) from July 1997 to June 1998. Its age, growth and reproduction were studied. Fish ranged in size from 157 to 610 mm total length and weighed from 60 to 4000 g wet weight. There were fish aged 1+ to 7+ years old in the samples. Direct scale readings were made by counting the number of rings. These were compared with the data obtained by backcalculating the lengths at different ages. These two methods were in agreement and showed that the growth rate of gilthead seabream in Mellah lagoon is very high compared to other study areas. The growth parameters of the Von Bertalanffy equation were: L∞ = 55.33 cm, K = 0.513, t0 = - 0.282, with F’ = 7.359. The fitted length-weight relationship was W = 1.292. 10-2 L3.06. The reproductive season extended from October to January, with a peak in December. Sex inversion occurred at a total length of 44 cm. Sexual maturity was reached at 32.6 cm total length.