Studying the migratory habits of sea turtles

Science : Because leatherback sea turtles are endangered, a group of researchers at Stanford University has started looking at their migratory patterns to try to determine ways to protect the aquatic reptiles. The group’s results have been published in Proceedings of the Royal Society B. Adult sea turtles lay their eggs on Costa Rican beaches along the eastern Pacific Ocean. Once hatched, the babies make their way to the sea. Because young turtles are too small to carry tracking devices, marine biologist George Shillinger and colleagues decided to focus on the ocean currents instead. They used computer simulations to study the movement of the water, and they placed virtual floating markers to simulate the swimming turtles. Apparently, the currents off Playa Grande in Costa Rica can take the turtles the farthest, nearly 1500 kilometers into the deep sea; the simulated turtles launched from beaches farther to the north and south barely left the shoreline. More work needs to be done, however, because currents are only one factor. Although the turtle simulations float, real turtles paddle and may go in directions the computer simulations can’t predict.