The influence of the sun's position and elevated cues on the orientation of hatchling sea turtles

Abstract

1. 1. Hatchling sea turtles, Chelonia mydas and Eretmochelys imbricata, reacted to the position of the sun during tests of seafinding ability by deviating from the shortest route to the water. 2. 2. Cutting off cues from close to the horizon disrupted orientation. Introduction of artificial cues elevated above the normal horizon into an otherwise uniform visual situation re-established orientation. 3. 3. The results suggest that any kind of visual stimulus has some effect on the seafinding orientation of hatchling turtles and that this orientation depends on a relatively uncomplicated type of tropotactic reaction.