Integrating Satellite Remote Sensing and Animal-Borne Telemetry to Characterize Loggerhead Turtle, Caretta caretta, Habitat Use and Movement in the Alboran Sea

Satellite remote sensing provides spatially continuous environmental information that can help interpret the movements and habitat use of highly mobile marine species. Here, we combined satellite telemetry, including fast GPS and depth sensors, from seven loggerhead turtles (Caretta caretta) with oceanographic data to investigate movement, diving behaviour, and habitat suitability in the Alboran Sea, western Mediterranean. Turtle locations were associated with cooler and slightly fresher waters and higher current speeds, characteristic of the Atlantic inflow. Daily displacements averaged 34.2 ± 22.1 km day−1. Movement direction became increasingly aligned with surface currents at higher current speeds, although alignment varied among individuals. Vertical behaviour also varied markedly among individuals, with no consistent circadian pattern. A MaxEnt model, with limited discriminatory ability, predicted lower relative suitability in the centre of the western mesoscale gyre and higher values along its periphery, the Atlantic inflow and in the southeastern Alboran Sea, with a seasonal shift between western and eastern areas. Given the small sample size, unequal tracking durations and limited temporal coverage of the data, these patterns should be regarded as preliminary. By coupling biologging observations with Earth-observation products, this study illustrates how remotely sensed oceanographic conditions can provide environmental context for interpreting individual variability in movement and behaviour of highly mobile marine species.