Study: Sea Turtles Follow Magnetic Fields To Their Home Beaches To Lay

Jan 16, 2015

A new study shows that sea turtles use magnetic fields to find the beaches where they hatched. They often lay their own eggs there.
Credit US Fish and Wildlife Service

Sea turtles follow the earth's magnetic fields to find the beaches where they hatched to lay their own eggs.

UNC-Chapel Hill researcher and report co-author Roger Brothers says they want soft, undisturbed sand at the right temperature, but it's hard to guage that from out in the ocean.

“So the only way the female turtle can actually be sure that she's nesting in a place that's favorable for egg development, is to nest on the same beach where she hatched as a hatchling. The logic being that, “’If it worked for me, it should work for my offspring.’”

Brothers says sometimes conservationists put metal cages over turtle nests to protect them, but that can interfere with the magnetic field.

“We just need to take this sort of thing into account when we are trying to conserve the species, and hopefully find some material that can effectively protect the eggs from predation, but also not disturb their navigational abilities later in their life.”

Even when a turtle finds its natal beach, Brothers says development or the presence can cause a sea turtle to seek out a different spot to build a nest.