Dancing turtles show how animals use magnetic fields as a map

Loggerhead sea turtles can learn and remember magnetic field signatures of specific locations, according to a study published Wednesday in Nature.

Researchers found that turtles not only navigate using Earth’s magnetic field but also create mental maps of key areas like feeding and nesting spots.

“This is the first direct evidence that an animal can learn and remember the natural magnetic signature of a geographical area,” said Kayla Goforth of the University of North Carolina, who led the study.

For the experiment, young turtles were placed in a tank surrounded by magnetic coils mimicking the Atlantic Ocean’s field. The magnetic field was shifted daily between regions like the North American coast and the Gulf of Mexico.

When fed in specific magnetic conditions, the turtles began to associate the area with food. Their excitement—flapping, spinning, and opening their mouths—was dubbed the "turtle dance."

Even four months later, the turtles remembered the areas tied to feeding.

“This behavior shows strong evidence of turtles learning and retaining magnetic signatures for specific geographical locations,” Goforth said.

Interestingly, the turtles’ map-making ability functioned even when researchers tried to interfere with chemical magnetoreception. However, their compass sense—tested under West African magnetic conditions—was disrupted by radiofrequency emissions, causing disoriented swimming.

Researchers concluded that turtles likely use two distinct systems: a chemical process for their compass and another, yet-unknown mechanism for map-making.

The findings align with observations of birds and amphibians, suggesting that multiple migratory species may rely on dual magnetic receptors.