Environmental predictors of foraging and transit behaviour in flatback turtles Natator depressus

Sea turtles migrate between nesting beaches and foraging grounds, but little is known about the cues they use to direct these migrations, and the habitats that define their foraging grounds. Here, we used satellite telemetry to follow the movements of 11 flatback turtles Natator depressus after nesting on islands in the waters off the coast of the Kimberley region of northern Australia. State-space models were used to objectively define inter-nesting, migration and foraging behaviour during the 327 +/- 315 d (mean +/- SD) that the turtles were tracked. These animals migrated along the coast in water depths of 63 +/- 5 m to foraging grounds on the mid-Sahul Shelf in the Timor Sea in average water depths of 74 +/- 12 m, 135 +/- 35 km from shore. Distribution modelling showed that flatback turtles preferred foraging and transiting in clear waters (suspended material