Sex ratio, reproduction, and growth of the gilthead sea bream, Sparus aurata (Pisces: Sparidae), in the Gulf of Gabes, Tunisia

Abstract

Samples (N = 1065) of the gilthead seabream, Sparus aurata, were collected in the Gulf of Gabes (Tunisia) from March 2008 to February 2010. This species is a protandric hermaphrodite. Total length (TL) ranged from 10.10 to 35.00 cm and the number of males to each female was 1.18:1. The reproductive season extended from October to February and maximum spawning activity occurred from December to January. The size at which 50% of the males reached maturity was 17.63 ± 0.28 cm TL and the size at which 50% of males transformed into females was 18.75 ± 0.19 cm TL. The length-weight relationship for all individuals was described by the following parameters: a = 0.0107 and b = 3.0797. Age of fish ranged from 0 to 8 years. Estimates of the von Bertalanffy growth parameters for the whole sample were: L∞= 38.28 cm, k = 0.202 year–1, and t0 = –1.888 years.