• Surfers are sticking two huge eyes to the undersides of their boards to deter great white sharks from attacking them.
• Great whites commonly attack surfers. They are ambush predators who prefer to sneak up on prey from below or behind.
• Shark Eyes, founded by surfer and shark attack survivor Shanan Worrall, produce the eyes, meant to make sharks think they have lost the element of surprise.
• Other methods include wearing devices which emit electro-magnetic pulses which cause sharks to convulse when they get too close. 
• Great white sharks have been seen with increasing frequency around the coasts of the US in recent years due to the booming seal population.
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Surfers are sticking large eyes on the bottom of their surfboards to deter sharks from attacking them, as more and more sharks are sighted off the coast of the US.

The technique is one of several, listed by the Wall Street Journal, being used by surfers to stay safe from attacks, which are still extremely rare but can be fatal.

Great whites are ambush predators, and researchers believe that they are less likely to attack if they believe they have been seen — hence the eyes.

The east and west coasts of the US have seen an influx of great white sharks in recent years. At least 300 great whites have been spotted off the East Coast, and 2,400 great white sharks are said to be patrolling waters to the west of the US.

Australian surfer Shanan Worrall founded Shark Eyes in 2017 after he was involved in three great white sharks attacks, and lost a friend to one.

His company's product consists of two large eye stickers which can be attached to surfboards, diving gear, and surfing clothing. It "intends to make the shark think it's been spotted" which deters it from attacking without the element of surprise, according to Worrall. 

Read more: Watch the moment a great white shark jumped out of the water and shocked boaters off of Cape Cod

Worrall cites surfer safety studies and the natural world as his inspiration. Many animals have developed eye-shaped markings to ward off ambush predators. 

Richard Pierce, conservationist and founder of the Shark Conservation Society, told INSIDER the eyes are a plausible deterrent.

"Great Whites are primarily ambush predators, and so it could be that if they were convinced their prey was observing them, they make look for an easier opportunity elsewhere," he said.

A number of other deterrents are used by surfers to ward-off sharks.

Surfers are adding stripes to the legs of their wetsuits, which they hope will make them look less like seals, the main prey for great whites.

Another safety device, Ocean Guardian's SharkShield device, emits a electrical field is meant to trigger spasms in a shark's electrical receptors if it gets within range.

The manufactures of Shark Eyes and SharkShield stress that there is no fail-safe defense against a shark attack.

While great white sharks are reportedly involved in more attacks on humans than any other kind of shark, the chances of getting bitten by one are only one in 3.75 million, according to the International Wildlife Museum.

The boom in great whites off the US coast in recent years is thanks to the rebounding population of grey seals, according to the Atlantic White Shark Conservancy.

East coast surfer A.J. Salerno told the Wall Street Journal: "We've been bullied out of the water by the sharks."

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