Mixed-stock analysis in green turtles Chelonia mydas: mtDNA decipher current connections among west Atlantic populations
Résumé
The green turtle Chelonia mydas undertakes wide-ranging migrations between feeding and nesting
sites, resulting in mixing and isolation of genetic stocks. We used mtDNA control region to
characterize the genetic composition, population structure, and natal origins of C. mydas in the
West Atlantic Ocean, at one feeding ground (State of Rio de Janeiro, Brazil), and three Caribbean
nesting grounds (French Guiana, Guadeloupe, and Suriname). The feeding ground presented
considerable frequency of common haplotypes from the South Atlantic, whereas the nesting sites
presented a major contribution of the most common haplotype from the Caribbean. MSA revealed
multiple origins of individuals at the feeding ground, notably from Ascension Island, Guinea Bissau,
and French Guiana. This study enables a better understanding of the dispersion patterns and
highlights the importance of connecting both nesting and feeding areas. Effective conservation
initiatives need to encompass these ecologically and geographically distinct sites as well as those
corridors connecting them.