Abstract

The migratory patterns and the features of the used areas displayed by sea turtles after the reproductive seasons are of the highest interest because of the ecological information that can be obtained from an ethological point of view. In this study, we characterized post-nesting movements and core areas of 73 individuals of four species (Eretmochelys imbricata –hawksbill-, Chelonia mydas –green-, Caretta caretta –loggerhead- and Lepidochelys kempii – kemp's ridley-) that were tracked from their nesting beaches. All species showed similar patterns of migration, moving relatively near to the coast (< 50 km), and above the continental shelf (slope < 0.2°) in shallow waters. Kemp's ridley migrated in waters with a median depth of 30 m, in contrast with loggerheads that move a cross deeper waters (IQR 0-1,500 m); although both species travel longer distances (IQR 860-1900 km) in comparison with greens and hawksbills (IQR 160-685 km). All species but kemp's ridley connect the Gulf of México with the Caribbean Sea, especially loggerheads, since they showed migrations from de Caribbean into the Gulf. At least one individual of all species traveled through two or more countries. After their migration, they exhibit one or two core areas that can be assumed as foraging grounds. Greens and hawksbills showed the smallest core areas (72 ± 65 km2) in shallow coastal waters, followed by loggerheads (150 ± 95 km2) which can use areas further away from land. Kemp's ridley exhibited the largest core areas, but also the highest variance (3400 ± 4800 km2). These results helped to discern migratory patterns between and amongst species, and provided basic information about the movements of post-nesting sea turtles in southern Gulf of Mexico to support management and conservation practices

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