Publications des scientifiques de l'IRD

Kadri H., Marouani S., Saidi B., Bradai M. N., Bouain A., Morize Eric. (2014). Age, growth, sexual maturity and reproduction of the thornback ray, Raja clavata (L.), of the Gulf of Gabes (south-central Mediterranean Sea). Marine Biology Research, 10 (4), p. 416-425. ISSN 1745-1000.

Titre du document
Age, growth, sexual maturity and reproduction of the thornback ray, Raja clavata (L.), of the Gulf of Gabes (south-central Mediterranean Sea)
Année de publication
2014
Type de document
Article référencé dans le Web of Science WOS:000326917800008
Auteurs
Kadri H., Marouani S., Saidi B., Bradai M. N., Bouain A., Morize Eric
Source
Marine Biology Research, 2014, 10 (4), p. 416-425 ISSN 1745-1000
The thornback ray Raja clavata is one of the most abundant bycatch species of trawl fishing in the waters of the Gulf of Gabes, but little is known about its life history in this area. The present study provides the first data on age and growth of this species in Tunisian waters, as well as additional data on its reproduction. The age of individuals was estimated by counting growth bands on central vertebral sections. Marginal increment and edge analysis supported the hypothesis of annual deposition of growth bands, with the opaque band formed during autumn. The parameters estimated from von Bertalanffy and Gompertz growth functions showed differences between sexes. The oldest thornback ray female was aged 15 years (104 cm TL), whereas the oldest male was 12 years (89 cm TL). Variations in the gonadosomatic and hepatosomatic indices of both sexes and the presence of vitellogenic activity in mature females during the year indicated that the species cannot be considered to be a continuous spawner. Males were found to mature between 55 and 75 cm TL, whereas females matured between 72.4 and 85 cm TL. The TL at which 50% of the population reached maturity was 67.44 and 81.42 cm for males and females, respectively. Males and female thornback rays mature, respectively, at approximately 5.3 and 7 years old.
Plan de classement
Limnologie biologique / Océanographie biologique [034] ; Ressources halieutiques [040]
Description Géographique
MEDITERRANEE ; TUNISIE
Localisation
Fonds IRD [F B010061298]
Identifiant IRD
fdi:010061298
Contact