Dolphins are sensitive to magnets

Dolphins are sensitive to magnets, French researchers have found. Magnetoreception, or the ability to sense magnetic fields, has long been thought to be one of the ways that marine animals navigate, but there was little evidence that this was the case.

So Dorothee Kremers and her colleagues from the Université de Rennes designed an experiment at the delphinarium in Port-Saint-Père to find out more. This is an outdoor facility where six bottlenose dolphins have access to four large pools. The scientists placed a barrel in one of the pools on several different occasions. Sometimes it contained a strongly magnetised block, and at other times a demagnetised one.

Both blocks looked and felt the same, so neither the people who put the barrel in place not the scientists who later watched videos of the dolphins interacting with the barrel knew which was which. In terms of echolocation, the way dolphins navigate by bouncing sound waves off objects, the barrel would have seemed the same whether it contained a magnet or not.

The researchers found that the dolphins consistently showed more interest in the barrel when it contained the magnetised block, swimming up to it more quickly. The fact that they seemed able to distinguish between the two blocks strongly suggests that they’re able to use geo-magnetic forces to navigate. Oh, and did we mention that they’ve also saved several people’s lives? There’s probably not much they can’t do.

Image via  Jay Ebberly’s Flickr.

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