In the second experiment, the researchers have studied the effect of the earths magnetic field on the turtles navigation system. They have shown, for the first time in natura, that marine turtles use the magnetic field of the earth to orientate themselves. When this field is disturbed by placing a powerful magnet on their heads, turtle navigation is not as good. But the fact that they can still return to their original egg-laying site shows that the geomagnetic field is not the only information source that they use. Researchers think the turtles may also use their sense of smell like certain sea birds or homing pigeons. This hypothesis remains to be proven
This work should improve conservation strategies for marine turtles, an endangered, officially protected species, by providing a better understanding of how they manage these long migrations between egg-laying and feeding areas.