Multiple haplotypes of Chelonia mydas juveniles in a threatened hotspot area in Southern Brazil

Abstract Mixed stocks are described for Chelonia mydas and the frequency of haplotypes in feeding areas can aid understanding of the genetic and ecological diversity, since with this information it is possible to identify the origin of the individuals. The current study aims to characterize and compare genetic diversity along the coast of Paraná with 17 other feeding areas in the Atlantic Ocean. A total of 285 samples from juveniles were DNA sequenced in the control region, resulting in the identification of 12 haplotypes, with a predominance of the CMA8 haplotype (69%) and the first registration of CMA23. For the study subjects, haplotypic and nucleotide diversity were 0.469 ± 0.032 and 0.00189 ± 0.00020, respectively, and comparisons with other feeding areas presented significant values for the majority of FST and ΦST. The results point to the importance of this region and provide evidence that over the years a mixed stock has used the region as a feeding area. This variation could be related to sea currents, climatic changes, and oceanographic characteristics that may alter the availability of food, water temperature, and the presence of turtles. The current results can be considered in conservation plans for Chelonia mydas.