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Conservation Genetics

, Volume 7, Issue 3, pp 353–369 | Cite as

Mitochondrial DNA diversity and phylogeography of endangered green turtle (Chelonia mydas) populations in Africa

  • A. FormiaEmail author
  • B.J. Godley
  • J.-F. Dontaine
  • M.W. Bruford
Article

Abstract

We analysed the genetic structure of seven nesting sites of the endangered green turtle (Chelonia mydas) in Africa using mitochondrial DNA control region sequences. Tissue samples were collected from 188 nesting females at six sites in West Africa and one in the Indian Ocean. A 488 bp fragment of the control region revealed 14 different haplotypes, 10 of which are previously undescribed. The most common haplotype (CM8) was observed in 157 individuals. All other haplotypes were closely related, except two divergent lineages: CM38, removed by four substitutions, and the three Indian Ocean haplotypes, distinguished by 31 substitutions. Significant differences in haplotype and nucleotide diversity were observed between Atlantic rookeries and among ocean basins. Analysis of molecular variance revealed high levels of differentiation between the Atlantic and the Indian Ocean populations but a much shallower Atlantic substructuring. Green turtle population genetic structure is thought to have been shaped by a dynamic succession of extinction and recolonisation of rookeries, by natal homing and occasional breakdown in nest-site fidelity. Mismatch distributions of pairwise differences between haplotypes at each rookery were found to be consistent with recent population expansion. We argue that demographic histories can be explained by scenarios at several temporal scales, including geological events, sea level fluctuations and more recent patterns of exploitation. We discuss management and conservation implications of our results for these threatened populations, identifying two ESUs (one in the Atlantic and one in the Indian ocean) and three MUs within the Atlantic.

Key words:

Africa control region haplotypes population structure sea turtles phylogeography 

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Notes

Acknowledgements

Numerous people and organisations provided invaluable field assistance. Sampling in São Tome and Principe was possible thanks to J. Fretey (Museum National d’Histoire Naturelle-Paris, PROTOMAC- Protection Tortues Marines d’Afrique Centrale), A. Billes (PROTOMAC), C.␣Aveling, J. Rosseel, O. Neves and B. Giannuzzi-Savelli (ECOFAC- Conservation et Utilisation Rationnelle des Ecosystemes Forestiers d’Afrique Centrale, funded by the European Union). Sampling in Equatorial Guinea was supported by L.␣Arranz and J. Mba (ECOFAC), R. Castelo Alvarez (Asociación Amigos de Doñana, Bioko), J.E. Garcia, J.C. Serrano and Julian Nzi Mba (CUREF – Conservación y Utilización Racional de los Ecosistemas Forestales, funded by the European Union), D. Eparalele (Ureca), C. Epota Nassau (Corisco). Sampling on Ascension Island was assisted by A.C. Broderick, F. Glenn and G.C. Hays (University of Wales, Swansea, UK) in association with the Ascension Island Turtle Group (as part of projects funded by the Ascension Island Administrator, Darwin Initiative, Foreign and Commonwealth Office Environment Fund and NERC – Natural Environment Research Council, UK). Sampling in Guinea Bissau was supported by P. Catry, C. Barbosa, A.␣Almeida, B. Indjai, P.J. Perrida, J. da Silva (IUCN, Ministry of Agriculture and Rural Development, Centre for Applied Research on Fisheries, National Institute for Research, the People of Canhabaque). Sampling in Comoros was carried out by S. Ahamada (Marine Conservation Programme – AIDE). We gratefully acknowledge the following for granting permits: Direcçao Geral das Florestas e Caça (Guinea Bissau), Ministere de la Production et de l’Environnement (Comoros), Ministério da Agricultura e Desenvolvimento Rural (São Tome and Principe), Ministerio de Bosques y Medio Ambiente (Equatorial Guinea), Department of the Environment Transport and the Regions (UK). We are also grateful to G. Hewitt, G.C. Hays and J.␣Tomás for helpful suggestions, Paola Ciccarelli for her help with some analysis, and two anonymous reviewers for valuable comments on the manuscript. This work was supported by a grant from the Marie Curie Training and Mobility of Researchers Programme of the European Union to A.F., by European Union support to ECOFAC in São Tome and Principe (J.-F.D.), and by grants from the Convention on Migratory Species, the Fondation Internationale du Banc D’Arguin, NERC and People’s Trust for Endangered Species to B.J.G.

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Copyright information

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • A. Formia
    • 1
    • 4
    Email author
  • B.J. Godley
    • 2
  • J.-F. Dontaine
    • 3
  • M.W. Bruford
    • 1
  1. 1.Biodiversity and Ecological Processes Research GroupSchool of Biosciences, Cardiff UniversityCardiffUK
  2. 2.Marine Turtle Research Group, School of Biological SciencesUniversity of Wales SwanseaSingleton ParkUK
  3. 3.Projecto Tàtô, ECOFACSão TomeSão Tome and Principe
  4. 4.Dipartimento di Biologia Animale e GeneticaFirenzeItaly

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