Shark Navigation

Pfft! Anyone can navigate with a smartphone… Try a compass!

This is Sandra Tsing Loh with the Loh Down on Science.

Many marine animals, like sharks and rays, migrate seasonally. How do they find their way?

Bryan Keller and team from Florida State University wondered if sharks use Earth’s magnetic fields.

They captured twenty bonnethead sharks and exposed them to different magnetic fields. One field mimicked an UN-familiar location north of the capture site. The other mimicked a familiar location south of the capture site. In both cases, the sharks’ movements were tracked using GoPro cameras.

In the unfamiliar field, the sharks swam randomly. BUT in the familiar field, they did something different. The sharks swam toward the magnetic waves similar to those of their capture location.

These findings show that sharks can use the Earth’s magnetic field to orient themselves! This ability is useful for long-distance seasonal migrations. Other animals may do this too!

Me? I’m trying to find my way OUT of these shark-infested waters. Eep!

Reference: Keller, B. A., Putman, N. F., Grubbs, R. D., Portnoy, D. S., & Murphy, T. P. (2021). Map-like use of Earth’s magnetic field in sharks. Current Biology, 31(13).