Global connectivity and genetic characterization of the hawksbill turtle (Eretmochelys imbricata) in the Islas del Rosario and San Bernardo Natural National Park, Colombia

Understanding the population dynamics of the hawksbill turtle (Eretmochelys imbricata), a critically endangered migratory species, is essential for effective conservation planning. This study examined the genetic structure, diversity, and connectivity of hawksbill turtles from PNN Rosario Islands, Colombia, using mitochondrial DNA sequences from the control region. Nineteen samples were amplified, yielding ten haplotypes integrated into a dataset of 396 sequences representing 1,872 individuals. A median-joining haplotype network revealed four phylogeographic clades spanning the western Atlantic, eastern Atlantic, and two Indo-Pacific lineages. Colombian samples clustered within the western Atlantic clade, sharing haplotypes with Puerto Rico, Brazil, and the Lesser Antilles while containing novel haplotypes. Diversity indices identified Colombia as one of the most diverse localities in the western Atlantic (h = 0.971 ± 0.027; π = 1% ± 0.005), whereas Cuba (h= 0.091 ± 0.049; π = 0.1% ± 0.001) and Guadeloupe (h= 0.131 ± 0.053; π= 0.1% ± 0.001) exhibited lower diversity. Pairwise F_st and Φ_st values indicated moderate to high differentiation across the region; because all comparisons were significant, values closer to 0 denote higher matrilineal affinity (e.g., Colombia–Puerto Rico, F_st = 0.102) whereas higher values reflect reduced affinity (e.g., Cuba–Mexico, F_st = 0.835). Mixed Stock Analysis showed that Colombia hosts a foraging aggregation primarily linked to Guadeloupe and Costa Rica. Together, these findings provide a phylogeographic context for hawksbill turtles in Colombia and highlight the need for coordinated, multinational conservation strategies.