Abstract
The analysis of mitochondrial DNA in loggerhead sea turtles (Caretta caretta) from eight foraging grounds in the Mediterranean and the adjoining Atlantic revealed deep genetic structuring within the western Mediterranean. As a consequence, the foraging grounds off the North-African coast and the Gimnesies Islands are shown to be inhabited mainly by turtles of the Atlantic stocks, whereas the foraging grounds off the European shore of the western Mediterranean are shown to be inhabited mainly by turtles from the eastern Mediterranean rookeries. This structuring is explained by the pattern of sea surface currents and water masses and suggests that immature loggerhead sea turtles entering the western Mediterranean from the Atlantic and the eastern Mediterranean remain linked to particular water masses, with a limited exchange of turtles between water masses. As the north of the western Mediterranean comprises mostly individuals from the highly endangered eastern Mediterranean rookeries, conservation plans should make it a priority to reduce the mortality caused by incidental by-catch in these areas.
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Acknowledgements
The samples from turtles on the Balearic archipelago were provided by the BMA tissue bank, with the support of the Pew Fellows Program in Marine Conservation and Earthtrust. These samples were analysed under the Life project “Protección de Praderas de Posidonia en LICs de Baleares” LIFE 2000/NAT/E/7303 and the project BOS2003-05904 of the Spanish Government (CICYT). We also thank the lab of Molecular Evolution of the Stazione Zoologica and specially the Professor Bernardi for his assistance in the analysis of the Italian samples. Moreover, the analysis of the samples from NE Spain was supported by the “Departament d’Agricultura Ramaderia i Pesca de la Generalitat de Catalunya”. The study complies with the current laws of Spain and Italy.
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Communicated by S.A. Poulet, Roscoff
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Carreras, C., Pont, S., Maffucci, F. et al. Genetic structuring of immature loggerhead sea turtles (Caretta caretta) in the Mediterranean Sea reflects water circulation patterns. Mar Biol 149, 1269–1279 (2006). https://doi.org/10.1007/s00227-006-0282-8
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DOI: https://doi.org/10.1007/s00227-006-0282-8