Titre :

Population structure of the European anchovy, Engraulis encrasicolus, in the SW Mediterranean Sea, and the Atlantic Ocean : evidence from otolith shape analysis

Auteur(s) :

Bacha, Mahmoud [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Jemaa, Sherif [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Hamitouche, Azzedine [Auteur]
Rabhi, Khalef [Auteur]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
Amara, Rachid [Auteur]
Université du Littoral Côte d'Opale [ULCO]
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]

Titre de la revue :

ICES JOURNAL OF MARINE SCIENCE

Pagination :

2429-2435

Éditeur :

Oxford University Press

Date de publication :

2014-11

ISSN :

1054-3139

Mot(s)-clé(s) en anglais :

Almeria-Oran front
anchovy
Atlantic
Mediterranean
otolith
shape analysis
stock identification.

Discipline(s) HAL :

Planète et Univers [physics]/Sciences de la Terre/Océanographie

Résumé en anglais : [en]

Understanding the influence of oceanographic features on the structure of fish population is of basic importance to population dynamics studies and fisheries management. The European anchovy (Engraulis encrasicolus) exhibits ...
Lire la suite >Understanding the influence of oceanographic features on the structure of fish population is of basic importance to population dynamics studies and fisheries management. The European anchovy (Engraulis encrasicolus) exhibits a complex population structure which has produced conflicting results in previous genetic studies. This study examines the variability in the shape of the anchovy's otolith as a tool for identifying different stocks, and investigates the effects of oceanographic features on population structure. Anchovies were analysed from seven locations in the SW Mediterranean Sea and Atlantic Ocean along the northwestern African (Morocco) and Portuguese (Bay of Cadiz) coasts. A combination of otolith shape indices and elliptic Fourier descriptors were investigated by multivariate statistical procedures. Within the studied area, three distinct anchovy stocks were identified: the Algero-Provençal Basin, the southern Alboran Sea, and the Atlantic Ocean (Morocco and Gulf of Cadiz). The separation of the stocks was based on non-parametric discriminant analysis returning a classification percentage. Over 81% of the separation of the stocks could be explained by oceanographic features. Shape variability of anchovy otoliths was associated with the presence of the Almeria-Oran front, and the strait of Gibraltar. The Alboran stock was distinct from the Algero-Provençal Basin and from the closest Atlantic stocks (Gulf of Cadiz or Atlantic coast of Morocco). Results are discussed and compared with those previously obtained by genetic studies. This study supports the efficiency of otolith shape analysis for the stock identification of anchovy, and highlights the role of oceanographic features in stock separation.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Collections :

• Laboratoire d'Océanologie et de Géosciences (LOG) - UMR 8187

Source :

Harvested from HAL