Habitat fidelity in hawksbill sea turtles

Climate change is altering habitat suitability and driving shifts in species distributions. To understand potential responses by mobile animals, it is essential to assess levels of plasticity in habitat use, ranging from transience to long-term fidelity. Here, we evaluate the fidelity of hawksbill sea turtles (Eretmochelys imbricata) to habitats used while foraging (our primary focus), migrating, and nesting. After satellite tracking 17 adult females from three Western Atlantic nesting areas, we then re-tracked them in a subsequent year. Of 15 turtles with sufficient data to assess interannual foraging area fidelity, 14 returned to the same home range, exhibiting overlap between successive 50% utilization distributions (UDs); the 15th individual shifted <10 km. Mean precision of fidelity, here expressed as the distance between centroids of successive foraging UDs, was 1.45 ± SD 2.3 km-less than the error associated with many satellite fixes. We also observed fidelity to inter-nesting home ranges and migratory pathways, though distinct deviations in migratory routes occurred. A paradigm of precise habitat fidelity is likely appropriate for adult hawksbills, yet merits further investigation across life history stages and global populations. Our results suggest that adult transience may have limited potential to contribute to projected distributional shifts.