Genetic diversity of the Green Turtle (Testudines: Cheloniidae: Chelonia mydas (Linnaeus, 1758)) population nesting at Kosgoda Rookery, Sri Lanka

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E. M.L. Ekanayake
T. Kapurusinghe
M. M. Saman
D. S. Rathnakumara
P. Samaraweera
R. S. Rajakaruna


We determined the genetic diversity of the Green Turtle Chelonia mydas (Linneaus, 1758) nesting at Kosgoda rookery, the second largest sea turtle aggregation on the southwestern coast of Sri Lanka.  Skin tissue samples were collected from 68 nesting females and genetic diversity was estimated using six microsatellite loci.  High genetic diversity was observed within the population as all loci analyzed were highly polymorphic with a total of 149 alleles observed.  The mean number of alleles per locus was 24.7 and the mean observed and expected heterozygosity across all loci were 0.75 and 0.93, respectively.  It appears that five out of six loci were not in Hardy-Weinberg equilibrium, while micro-checker analysis suggested that the Kosgoda Green Turtle population was possibly in equilibrium.  The viability of a population is unlikely to be reduced if high genetic diversity is maintained within it.  Although the Green Turtle population nesting at Kosgoda is small compared to other nesting rookeries in the world, the high genetic diversity observed suggests that the population may not be undergoing a bottleneck.

Article Details

Author Biographies

P. Samaraweera, Department of Molecular Biology and Biotechnology, Faculty of Science, University of Peradeniya, Peradeniya, Sri Lanka

Department of Molecular Biology and Biotechnology

R. S. Rajakaruna, Department of Zoology, Faculty of Science, University of Peradeniya, Galaha Road, Peradeniya 20400, Sri Lanka Postgraduate Institute of Science, University of Peradeniya, Galaha Road, Peradeniya 20400, Sri Lanka

Department of Zoology


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