Turtles navigate by magnetic compass
Sea turtles have a special talent for finding their way. From they hatch and fight their way to the ocean until they return 20-30 years later to lay eggs, they travel thousands of km in the ocean. Still, they often manage to find their way back to the very beach on which they were born. Scientists from the US University of North Carolina have found out how.
The scientists carried out DNA studies of 800+ individuals of the Caretta caretta species, which exists in several places of the world and crosses entire oceans – some complete 12,000 km across the Pacific. In this project, scientists focused on turtles that lay eggs on the coast of Florida. They mapped out the geomagnetic conditions of different beaches and compared them to the DNA of sea turtles. The results showed that turtles which were very closely related also chose beaches with the same magnetic conditions, i.e. on which the strength of the magnetic field is the same, and where the angle between the magnetic field and Earth’s surface is the same. The result means that the turtles do not necessarily choose the exact beach on which they were born, but just a beach which is similar, when it comes to magnetic conditions.
The conclusion forms an essential part of the identification of the most important breeding places of sea turtles, so the animals can be protected from they are very young. Almost all sea turtle species in the world are endangered.