Great white shark stalks kayaker until it encounters his secret weapon; video

A kayak fisherman in Australia had just lost a good-sized pink snapper when he heard a big splash behind him.

“When I turned around I was greeted with a 4-meter [13-foot] shark,” Michael Robertson wrote on his YouTube video description, later telling PerthNow, “I’m pretty sure he gobbled the snapper I lost.”

Robertson was kayak fishing with a friend in Cockburn Sound on Wednesday when he encountered a great white shark. Once the presence of the shark became known, Robertson began quickly paddling away, but then noticed he had company.

“It’s just following me,” he said in the video. “A great white’s following me, man. It’s big, whatever it is.”

Robertson dipped his camera into the water and, as luck would have it, captured the moment the great white shark closed in and encountered his secret weapon. The long line below the kayak in the Daily Mail video above is a Shark Shield, an electric device that repels sharks using an electromagnetic field.

The Shark Shield doesn't harm the shark but causes it to experience uncomfortable muscle spasms.

“It followed me for about two or three minutes and disappeared when it came within range of my Shark Shield,” Robertson wrote.

Here is Robertson’s entire video: wrote, “Shark Shield saves Perth angler from shadowing ‘great white.'”

Fortunately the deterrent worked. If it hadn’t, Robertson pictured a more terrifying scenario.

“The kayak is 13-feet long, and the shark was easily as long and a lot wider,” Robertson told PerthNow. “I was thinking, ‘He could take a bite and take the whole front off if he wanted.'”

RELATED: Shark pursues kayaker to beach in suspenseful encounter off Florida; video

After the encounter, Robertson and Campbell Ryan headed back in. Ryan later told Robertson he had seen a "bloody great fin" behind him.

Robertson told PerthNow that he had hoped a couple of fishermen in a small boat would come and scare the great white shark away, but as it turned out, his secret weapon did the trick quite nicely.

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