Age, growth and mortality of the striped seabream Lithognathus mormyrus (Linnaeus, 1758) in the Gulf of Tunis (Central Mediterranean Sea)
|Author(s)||Khaldi Asma1, Chater Ines1, Elleboode Romain2, Mahé Kelig2, Chakroun-Marzouk Nadia1|
|Affiliation(s)||1 : Université de Tunis El Manar, Faculté des Sciences de Tunis, LR18ES41 Laboratoire d’écologie, biologie et physiologie des organismes aquatiques, 2092 Tunis El Manar, Tunisie
2 : IFREMER (Institut Français de Recherche pour l'Exploitation de la Mer), Pôle National de Sclérochronologie, 150 quai Gambetta, BP 699, 62321 Boulogne Sur Mer, France
|Source||Journal Of The Marine Biological Association Of The United Kingdom (0025-3154) (Cambridge University Press (CUP)), 2021-02 , Vol. 101 , N. 1 , P. 159-167|
|Keyword(s)||Age, growth, Gulf of Tunis, Lithognathus mormyrus, Lopt, mortality, otolithometry, Sparidae, weight–, length relationship|
Despite the high commercial value of the striped seabream Lithognathus mormyrus (Linnaeus, 1758) in the Gulf of Tunis, biological data on its age, growth and exploitation rate are lacking. With the aim of estimating growth parameters, 516 individuals, ranging from 6–27.5 cm total length and from 3.5–293.5 g total weight, were collected from the artisanal fishing fleet between February 2014 and July 2016. The somatic growth presented a positive allometry and was described by the equation TW = 6.54 10−3TL3.213. The monthly analysis of the marginal increment of the otoliths revealed that only one annulus was deposited per year. The estimated von Bertalanffy growth parameters were: L∞ = 30.18 cm, k = 0.303 year−1 and t0 = −1.42 years. Total and natural instantaneous rates of mortality were respectively Z = 0.784 year−1 and M = 0.698 year−1. Exploitation rate (E = 0.1) showed that the Gulf of Tunis stock of L. mormyrus is not overexploited. The estimated length class giving highest yield (Lopt) was 17.15 ± 1.71 cm.