LED lights may keep great white sharks away from surfers, new study reveals

By RNZ

A new study is offering a ray of hope for shark-fearing beachgoers after discovering LED lights which could be attached to surfboards deterred great whites.

Australian researchers towed seal-shaped boards fitted with lights across great white-teeming South African coastal waters to discover which configuration attracted the most attention, according to the BBC.

The lights distorted the silhouette of their “decoys” on the ocean’s surface and limited the ability of the great whites to see against the sunlight.

Auckland University marine scientist Dr Riley Elliott, known as New Zealand’s “Shark Man”, has had his fair share of close encounters.

Shark expert Dr Riley Elliott.

He directed a tiger shark documentary off Norfolk Island and, in 2019, while conducting research for his PhD, a hungry mako shark tried to bite his boat.

Rather than fleeing from the marine predator, Elliot jumped into the water and filmed the creature up close.

He spoke to Jim Mora of RNZ’s Sunday Morning and said people’s fear of the sharks far outweighs their danger, with the average number of yearly shark attacks worldwide hovering around 70, of which only five or six result in fatalities.

“It’s only a handful of times a year, but every one is tragic.”

A shark was sighted swimming near the shores of the beach in Mount Maunganui earlier this year.

But while you are more likely to die from a lightning strike, anything that reduces the chance of shark attacks is a win-win for both sharks and swimmers, he said.

“The science is worthy. The results ... are promising.

“And if wearing a shark band or shark guardian or LED light under your surfboard makes you feel more comfortable, then cool.”

Particularly because the research focused on great whites, which are common to New Zealand waters and the cause of our most recent shark-related fatality.

“This [study] is particularly designed for great white sharks because they are the ones hunting seals, and surfers get mistaken for seals sometimes.

“[Great white sharks] hunt by silhouette looking up from 10m down on the bottom and [in] murky water, generally [around] dusk and dawn, trying to get that ambush approach, and they see that silhouette of a seal and they make a decision.

“[They’re] incredibly intelligent, and anything that shows them that this might not be what they think it is usually stops them – and that could save someone’s life.”

A new study is offering hope for shark-fearing beachgoers after it was discovered that LED lights which could be attached to surfboards deterred great whites. Photo / Clinton Duffy

The science, he said, was complex and simple. Light shining downwards would potentially obscure the surfboard’s profile, potentially making it invisible to the shark below.

The challenge, he said, would be convincing surfers to stick a large “spotlight” on their boards.

“Convincing surfers to take that on. Well, you know, I’m a surfer, and if it ain’t broke, don’t fix it. It’s kind of the mentality, unfortunately.

“At the end of the day, a lot of surfers – and this goes for mountaineers and snowboarders and whatever, people who play in nature – generally tend to accept the risks that come with it.”

He also cautions against the notion a device like this would be 100% effective.

“I don’t think it’s going to solve all the world’s shark problems.”

“It’s a very difficult thing to control nature, though, and I equate this to a bull with an electric fence.

“Now, you might stop one walking up and sniffing it, but one that’s charging is quite hard to [deter].”

He said beachgoers can “dress up like lollipops and put elastic bands on their hands and electric currents around their legs, LEDs, whatever”, but understanding shark behaviour was people’s best bet to stay safe.

“The science is cool. I’m into it ... Human mentality is the harder thing to change.”

- RNZ