ESR 3:23-30 (2007)  -  doi:10.3354/esr003023

ABSTRACT: Artificial lighting disrupts sea turtle hatchling orientation from the nest to the sea. We studied how a light-induced landward crawl affects the later ability of hatchlings to crawl to the sea, and to swim away from the shore from a dark beach. A brief (2 min) landward crawl had no effect on swimming orientation as long as surface waves were present. In a calm sea, landward-crawling hatchlings failed to swim offshore, while those crawling seaward were well oriented. A long (2 h) crawl toward a landward light source, however, impaired the ability of hatchlings to crawl seaward. These results demonstrate that orientation toward artificial light sources compromises the ability of hatchlings to respond to natural orientation cues, both on land and in the sea. Based on these results, we suggest several changes to current management practices used when releasing misoriented turtles in the wild.

KEY WORDS: Sea-finding · Orientation · Migration · Sea turtle · Loggerhead · Caretta caretta · Photopollution