Reproductive biology of the Egyptian sole, Solea aegyptiaca (Actinopterygii: Pleuronectiformes: Soleidae), in southern Tunisian waters (Central Mediterranean)

Abstract

AbstractSolea aegyptiaca (Chabanaud, 1927) is one of the most common Soleid species in southern Tunisian waters. This study provides the first detailed information on the reproduction biology of S. aegyptiaca in these areas. Samples of S. aegyptiaca were collected by trawl from the Gulf of Gabes (Tunisia) between April 2013 and March 2015. A total of 1638 specimens were examined, ranging from 9.7 to 30.7 cm total length. The sex ratio was in favour of males in smaller size classes and females in larger size classes. The macroscopic analysis of the gonads and the progression of the monthly values of the gonadosomatic index (GSI) indicated that the reproductive season extended from October to February, with GSI peaking in November and December for males and females respectively, and that spawning occurs once a year from November to February. The utilization of lipid reserves, stored predominantly in the liver as well as in muscles, was depicted. The estimated average length at first maturity was 22.31 ± 0.41 cm for males and 23.19 ± 0.184 cm for females. Total fecundity of mature females ranged from 14,160–62,700 eggs per fish, showing a significant increase with size, with an average of 33,020 ± 5239 eggs per fish.