Data/hora: 11/06/2024 01:36:22

Provedor de dados: | 5
País: | France
Título: | Otolith shape variation provides a marker of stock origin for north Atlantic bluefin tuna (Thunnus thynnus)
Autores: | Brophy, Deirdre; Haynes, Paula; Arrizabalaga, Haritz; Fraile, Igaratza; Fromentin, Jean-marc; Garibaldi, Fulvio; Katavic, Ivan; Tinti, Fausto; Karakulak, F. Saadet; Macias, David; Busawon, Dheeraj; Hanke, Alex; Kimoto, Ai; Sakai, Osamu; Deguara, Simeon; Abid, Nouredinne; Santos, Miguel Neves.
Data: | 2016
Ano: | 2016
Palavras-chave: | Elliptical Fourier analysis; Population structure; Stock mixture analysis.
Resumo: | Two stocks of bluefin tuna (Thunnus thynnus) inhabit the north Atlantic; the western and eastern stocks spawn in the Gulf of Mexico and the Mediterranean Sea respectively. Trans-Atlantic movements occur outside spawning time whereas natal homing maintains stock structure. Commercial fisheries may exploit a mixed assemblage of both stocks. The incorporation of mixing rates into stock assessment is precluded by uncertainties surrounding stock discrimination. Otolith shape descriptors were used to characterise western and eastern stocks of Atlantic bluefin tuna in the present study and to estimate stock composition in catches of unknown origin. Otolith shape varied with length and between locations and years. Within a restricted size range (200-297-cm fork length (FL)) the two stocks were distinguished with an accuracy of 83%. Bayesian stock mixture analysis indicated that samples from the east Atlantic and Mediterranean were predominantly of eastern origin. The proportion assigned to the eastern stock showed slight spatial variation; however, overlapping 95% credible intervals indicated no significant difference (200-297 cm FL: central Atlantic, 73-100%; Straits of Gibraltar, 73-100%; Morocco, 50-99%; Portugal 64-100%). Otolith shape could be used in combination with other population markers to improve the accuracy of mixing rate estimates for Atlantic bluefin tuna.
Tipo: | Text
Idioma: | Inglês

Identificador:

http://archimer.ifremer.fr/doc/00346/45745/45381.pdf

DOI:10.1071/MF15086

http://archimer.ifremer.fr/doc/00346/45745/

Editor: | Csiro Publishing
Formato: | application/pdf
Fonte: | Marine And Freshwater Research (1323-1650) (Csiro Publishing), 2016 , Vol. 67 , N. 7 , P. 1023-1036

Fonte:

CSIRO 2016 Open Access

info:eu-repo/semantics/openAccess

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