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Conservation Genetics

, Volume 11, Issue 4, pp 1587–1591 | Cite as

Evidence of olive ridley mitochondrial genome introgression into loggerhead turtle rookeries of Sergipe, Brazil

  • Estéfane Cardinot Reis
  • L. S. Soares
  • G. Lôbo-Hajdu
Short Communication

Abstract

The coastline of Sergipe state hosts the main Brazilian nesting sites of Lepidochelys olivacea (Eschscholtz, 1829). The second most abundant species of turtles in Sergipe is Caretta caretta (Linnaeus, 1758). Both sea turtle species, respectively known as olive ridley and loggerhead, are currently listed as endangered by the International Union for the Conservation of Nature and Natural Resources. The genetic diversity of the Sergipe loggerhead population (N = 51) was assayed by analyzing 627 bp from the control region of mitochondrial DNA in nesting females. Three haplotypes were identified: CC-A4, CC-A24 and CC × LO. The last one was recorded for specimens considered hybrids because they represent L. olivacea’s mtDNA, but had the external morphology of C. caretta or of a mixture of both species. Based on the two types of hybrids, it was hypothesized that at least two hybridization events had occurred: a more ancient hybridization event, accompanied by introgression (F2 or later backcrosses), and a recent one (F1), both of which involving the same L. olivacea haplotype. The incidence of L. olivacea mitochondrial genome introgression into the C. caretta rookeries was only observed in Sergipe, which could be related to the large numbers of L. olivacea in this region and an overlap of reproduction periods and distribution areas of both species. This may also be associated to global warming since it might alter the sex ratio of sea turtles, thus facilitating interspecific mating. Awareness of gene flow between these species will significantly influence the development and implementation of adequate management strategies.

Keywords

Sea turtles Hybridization mtDNA control region Genetic diversity Conservation strategies 

Notes

Acknowledgments

We are grateful to CENPES/PETROBRAS (Centro de Pesquisas da PETROBRAS) for supporting the “Mamíferos e Quelônios Marinhos” project, which included this study. The Projeto TAMAR-ICMBio staff collected the samples and provided the necessary field assistance. We acknowledge CAPES, PROCIÊNCIA-SR2-UERJ, FAPERJ and CNPq/MCT for fellowships and grants. The present study followed all ethical guidelines and legal requirements of Brazil for sampling an endangered species.

References

  1. ACCSTR (2009) Archie Carr center for sea turtle research, marine turtle DNA sequence patterns. University of Florida. http://www.accstr.ufl.edu/ccmtdna.html. Downloaded on 01 Sep 2008
  2. Allendorf FW, Leary RF, Spruell P, Wenburg JK (2001) The problems with hybrids: setting conservation guidelines. Trends Ecol Evol 16:613–622CrossRefGoogle Scholar
  3. Bass AL, Good DA, Bjorndal KA, Richardson JI, Hillis ZM, Horrocks JA, Bowen BW (1996) Testing models of female reproductive migratory behavior and population structure in the Caribbean hawksbill turtle, Eretmochelys imbricata, with mtDNA sequences. Mol Ecol 5:321–328PubMedGoogle Scholar
  4. Bickham JW (1981) Two-hundred-million-year-old chromosomes: deceleration of the rate of karyotypic evolution in turtles. Science 212:1291–1293CrossRefPubMedGoogle Scholar
  5. Bowen BW (2003) What is a loggerhead turtle? The genetic perspective. In: Bolten AB, Witherington BE (eds) Loggerhead sea turtles. Smithsonian Books, Washington, DC, p 319Google Scholar
  6. Bowen BW, Karl SA (1996) Population genetics, phylogeography and molecular evolution. In: Lutz PL, Musick JA (eds) The biology of sea turtles, vol 1. CRC Press, Boca Raton, pp 29–50Google Scholar
  7. Bowen BW, Meylan AB, Ross JP, Limpus CJ, Balazs GH, Avise JC (1992) Global population structure and natural history of the green turtle (Chelonia mydas) in terms of matriarchal phylogeny. Evolution Int J org Evolution 46:865–881Google Scholar
  8. Bowen BW, Kamezaki N, Limpus CL, Hughes GH, Meylan AB, Avise JC (1994) Global phylogeography of the loggerhead turtle (Caretta caretta) as indicated by mitochondrial DNA haplotypes. Evolution Int J org Evolution 48:1820–1828Google Scholar
  9. Carthy RR, Foley AM, Matsuzawa Y (2003) Incubation environment of loggerhead turtle nests: effects on hatchling success and hatchling characteristics. In: Bolten AB, Witherington BE (eds) Loggerhead sea turtles. Smithsonian Books, Washington, DC, p 319Google Scholar
  10. Conceição MB, Levy JA, Marcovaldi MA (1990) Eletrophoretic characterization of a hybrid between Eretmochelys imbricata and Caretta caretta (Cheloniidae). Comp Biochem Physiol B 97:275–278CrossRefGoogle Scholar
  11. Dodd CK, Morgan GS (1992) Fossil sea turtles from the early Pliocene bone valley formation, central Florida. J Hered 26:1–8Google Scholar
  12. Foley AM, Peck SA, Harman GR, Richardson LW (2000) Loggerhead turtle (Caretta caretta) nesting habitat on low-relief mangrove islands in southwest Florida and consequences to hatchling sex ratios. Herpetologica 56:433–445Google Scholar
  13. Hahn AT, Soares LS, Bonatto SL (2007) Variabilidade genética da tartaruga oliva (Lepidochelys olivacea) no Brasil através de marcadores microssatélites: dados preliminares. In: Estrades A (ed) Libro de Resúmenes de las III Jornadas de Conservación e Investigación de Tortugas Marinas en el Atlántico Sur Occidental. Piriápolis, Uruguay, p 70Google Scholar
  14. Hays GC, Broderick AC, Glen F, Godley BJ (2003) Climate change and sea turtles: a 150 year reconstruction of incubation temperatures at a major marine turtle rookery. Glob Chang Biol 9:642–646CrossRefGoogle Scholar
  15. IUCN (2008) International union for the conservation of nature and natural resources. 2007 IUCN red list of threatened species. http://www.iucnredlist.org/. Downloaded on 01 Sep 2008
  16. Karl SA, Bowen BW, Avise JC (1995) Hybridization among the ancient mariners: characterization of marine turtle hybrids with molecular genetic assays. J Hered 86:262–268PubMedGoogle Scholar
  17. Lara-Ruiz P, Lopez GG, Santos FR, Soares LS (2006) Extensive hybridization in hawksbill turtles (Eretmochelys imbricata) nesting in Brazil revealed by mtDNA analyses. Cons Gen 7:773–781CrossRefGoogle Scholar
  18. Lutcavage ME, Plotkin P, Witherington B, Lutz PL (1997) Human impacts on sea turtle survival. In: Lutz PL, Musick JA (eds) The biology of sea turtles, vol 1. CRC Press, Boca Raton, pp 387–409Google Scholar
  19. TAMAR-IBAMA (2005) Relatório Técnico de Atividades Projeto Tamar-Sergipe temporada 2004/2005. ISSN 1677-4701, p 116Google Scholar
  20. Mallet J (2005) Hybridization as an invasion of the genome. Trends Ecol Evol 20:229–237CrossRefPubMedGoogle Scholar
  21. Marcovaldi MA, Marcovaldi GG (1999) Marine turtles of Brazil: the history and structure of Projeto TAMAR-IBAMA. Biol Conserv 91:35–41CrossRefGoogle Scholar
  22. Marcovaldi MA, Godfrey MH, Mrosovsky N (1997) Estimating sex ratios of loggerhead turtles in Brazil from pivotal incubation durations. Can J Zool 75:755–770CrossRefGoogle Scholar
  23. Mrosovsky N (1994) Sex ratios of sea turtles. J Exp Zool 60:1012–1016Google Scholar
  24. Pike DA, Antworth RL, Stiner JC (2006) Earlier nesting contributes to shorter nesting seasons for the Loggerhead sea turtle, Caretta caretta. J Herpetol 40:91–94CrossRefGoogle Scholar
  25. Reis EC (2008) Caracterização genética e filogeografia de populações de tartarugas marinhas da espécie Caretta caretta (Linnaeus, 1758) no litoral brasileiro. M.Sc. Thesis, Universidade do Estado do Rio de Janeiro, Rio de JaneiroGoogle Scholar
  26. Reis EC, Albano RM, Bondioli ACV, Soares LS, Lôbo-Hajdu G (2009) Detection of polymorphisms of the mtDNA control region of Caretta caretta (Testudines: Cheloniidae) by PCR-SSCP. Genet Mol Res 8:215–222CrossRefPubMedGoogle Scholar
  27. Silva ACCD, Castilhos JC, Lopez GG, Barata PCR (2007) Nesting biology and conservation of the olive ridley sea turtle (Lepidochelys olivacea) in Brazil, 1991/1992 to 2002/2003. J Mar Biol Assoc UK 87:1047–1056CrossRefGoogle Scholar
  28. Soares LS (2004) O uso da análise genética da região controle do mtDNA na identificação das populações de tartarugas cabeçudas (Caretta caretta, Linnaeus 1758) nas áreas de desova e captura incidental no litoral brasileiro. M.Sc. Thesis, Pontifícia Universidade Católica de Minas Gerais, Belo HorizonteGoogle Scholar
  29. TAMAR-IBAMA (2006) Relatório Técnico de Atividades Projeto Tamar-Sergipe temporada 2005/2006. ISSN 1677-986X, p 107Google Scholar
  30. Zangerl R (1980) Patterns of phylogenetic differentiation in the Toxochelyid and Cheloniid sea turtles. Am Zool 20:585–596Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Estéfane Cardinot Reis
    • 1
  • L. S. Soares
    • 2
  • G. Lôbo-Hajdu
    • 1
  1. 1.Instituto de Biologia Roberto Alcântara Gomes, Departamento de Genética, Laboratório de Genética Marinha (LGMar)Universidade do Estado do Rio de Janeiro (UERJ)Maracanã, Rio de JaneiroBrazil
  2. 2.Fundação Centro Brasileiro de Proteção e Pesquisa das Tartarugas MarinhasProjeto TAMAR-ICMBioRio Vermelho, SalvadorBrazil

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