Let there be light!
That’s what shark researchers are saying after finding that LED lights on surfboards could be the key to preventing great white shark bites.
Australian scientists have published the results of a six-year shark study that could lead to a revolution in surfboard design.
“What we’ve been trying to do is understand how sharks see their prey. And with an understanding of that, see if we can create some shark deterrents, which protect people and also sharks,” said Macquarie University Professor Nathan Hart.
The researchers went to the shark-infested waters of Mossel Bay in South Africa to test out how lights impact great white sharks.
While driving a boat, the researchers put out on the water a seal-shaped foam decoy — and saw how the sharks responded to that decoy.
“What we found out is if you put lights on the bottom of the decoys, the sharks leave them alone,” Hart said. “And so we think this tells us a lot about how sharks see the world, and how they detect and target their prey.
“But it also potentially gives us an insight into how we can develop a non-lethal shark deterrent, especially for surfers,” he added.
This light strategy is based on the counterillumination phenomenon in the ocean.
Some animals emit light from the underside of their body — which breaks up their silhouette to a predator that’s looking at them from below.
“We have shown these lights break up the silhouette of the surfboard into smaller pieces, and that’s clearly something that the shark doesn’t recognize as prey,” Hart said.
“It’s sort of like an invisibility cloak but with the exception that we’re splitting the object, the visual silhouette, up into smaller bits so it doesn’t all disappear,” he added. “And the lights need to be fairly bright to have this effect.”
Macquarie University Dr. Laura Ryan’s previous research found that sharks are possibly colorblind. Her research group also discovered that sharks don’t see as much detail as humans.
“They’re really good at detecting an object from far away, but not so good at seeing the fine detail of that object,” Ryan said.
“What we’re trying to do now is move from seal decoys to a surfboard prototype by embedding LEDs into the bottom of a surfboard,” she added.
Shark bites on humans are very rare, but it’s a risk that people accept when they go into the ocean.
“What we don’t want to see is people getting hurt, and we don’t want to see sharks getting killed as a result of that,” Hart said. “So we’ve very hopeful with this technology, along with others, could be used to reduce the risk of getting a shark bite and make it safer for people to go into the water.”