MELBOURNE, Aug. 7 (Xinhua) -- Sea turtles navigate across vast stretches of open ocean by maintaining a steady course for long periods before making occasional corrections, new research reveals.
The study, published in Science Advances, showed that sea turtles are not the precision navigators scientists once imagined. Instead of constantly steering toward their destination, they hold a steady course for hours, or even days, before checking their position and making a gentle course correction, according to a statement released Thursday by Australia's Deakin University.
The findings challenge the long-held assumption about how animals migrate, suggesting they instead use a simple but effective navigation strategy to find their way across thousands of kilometers of open ocean without landmarks.
The imperfect navigation may benefit sea turtles by helping them discover new habitats, including alternative nesting sites as rising sea levels threaten existing beaches, said lead author Professor Graeme Hays from Deakin University.
Researchers tracked green turtles travelling more than 1,000 km across the Indian Ocean from nesting beaches to feeding grounds using a satellite-linked compass tag that records the direction a turtle is pointing while swimming.
They found the turtles wandered off course before correcting themselves and continuing, instead of travelling directly to their target. The findings suggest the turtles rely on an internal magnetic compass and the Earth's magnetic field to guide them across featureless oceans, rather than simply drifting with ocean currents.
Hays said the new technology allows scientists to remotely measure not only an animal's location but also the direction it is travelling, which could improve understanding of the migrations of whales, sharks, tuna and other long-distance marine travelers, and support conservation efforts. ■