Filogeografia e estrutura populacional da Tartaruga de Couro, Dermochelys coriacea, em áreas de desova da Guiana Francesa, Martinica e Guadalupe

Abstract

The leatherback turtle Dermochelys coriacea is the most largely distributed sea turtle species and it is classified as critically endangered by the World Conservation Union. Nevertheless the Northwest Atlantic group is considered as under low risk and facing low threats, and includes some of the largest nesting rookeries with over 10,000 nests laid every year in the French Guiana. We analyzed two French Guiana nesting populations and some smaller populations from the French West Indies (Guadeloupe and Martinique), with the aim to investigate the diversity and demographic histories of these populations. We used 12 microsatellite loci, of which four were newly isolated, and mtDNA sequences of the control region and cytochrome b. The three rookeries (Cayenne, Awala and Guadeloupe/Martinique) showed limited although significant structuration with mitochondrial DNA and with nuclear DNA, corroborating the previous considerations as a single Regional Management Unit. Furthermore, bottlenecks were detected in all the populations, dating from the mid Holocene, which can be explained by the climate fluctuations of this period. We suggest that these populations should be managed as an evolutionary unit, but the local conservation efforts are necessary, since each nesting site hosts part of the genetic diversity.