Image copyright Achmat Hassiem

South African lifeguard Achmat Hassiem lost a leg in a shark attack off the coast of Cape Town. He went on to become a medal-winning Paralympian and a marine conservationist advocating the protection of endangered sharks.

"I don't know if you've ever seen a shark with its jaws dislocated. It's the scariest thing you've ever seen. And it's charging at you."

Hassiem grew up beside the ocean, learning, as he puts it, "to love and respect it with every tumbling wave". From the roof of the family house he would watch sharks breaching the surface as they hunted seals in False Bay.

Seeing "something of that size and weight launch itself out of the water is absolutely incredible", he says. "It's wildlife in its purest form."

But Hassiem never imagined he would survive an attack by one of these powerful ocean hunters - and save his brother from death or injury in the process.

Image copyright Greg Adams/AFP/Getty

In August 2006 the two siblings were taking part in an exercise with the local lifeguard. Playing the role of distressed swimmers, Hassiem was nearest to shore, with his brother another 15m (50ft) towards the horizon.

As the lifeguards launched their dinghy into the water, Hassiem looked out to sea.

"I'm staring into the ocean and something catches the corner of my eye, moving towards my brother. I saw this triangle becoming bigger and bigger and bigger," he says.

Anxious to identify this "massive triangle", Hassiem peered below the surface. "That's when I saw a 4.7m (16ft) great white shark attached to this dorsal fin. I couldn't believe how big this thing was."

Hassiem knew the shark would dive before launching an attack from below. Fearing he could be about to witness the shark breach with his brother in its jaws, his first thought was to distract the animal's attention.

"Immediately I started drumming on top of the water, trying to make a massive splash.

"My brother was playing the role of an unconscious patient, so he was just lying in the water with his face down.

"Luckily sharks tend to move towards sounds, and I saw this massive fin turn away from my brother."

But as it changed course, the shark also dived. And as the lifeguards plucked Hassiem's brother out of the ocean, the great white targeted a fresh prey.

"It swam right in front of me," says Hassiem. "It was so close I could move the shark past me with my hands actually touching its body.

"That's when absolute chaos came into play. I'm screaming, the guys on the [dinghy] catch a glimpse of what is happening, and absolute terror hits the skies.

"The next thing I know the shark opens its mouth and you see those massive jaws."

For a moment Hassiem hoped he might somehow be able to throw his leg over the animal and get on to its back, and that "the shark would just give me a lift to the shoreline, drop me off, and that would be our parting".

Unsurprisingly, it didn't work out that way.

Image copyright Achmat Hassiem

"My leg didn't want to come forward and I couldn't understand why," he explains. "That's when I saw that half of my leg was in the shark's mouth already. I didn't feel it bite down at all."

Shaking Hassiem like "a doll in its mouth", the great white turned away from shore, pulled him under and headed downwards.

With the shark's teeth clamped around his right shin, Hassiem used his free leg to kick at the animal's head. His attacker shook him again, and he heard a "cracking sound".

"Boom - my leg just split, broke in two," says Hassiem. "I didn't feel it at all."

Who better to speak up for sharks than a shark attack survivor? Achmat Hassiem, Paralympic medallist

Desperate for air after being pulled a long way down, and finally free of the shark's crushing bite, Hassiem immediately made for the surface. He flung an arm out of the water, hoping his lifeguard colleagues would see the splash.

"I felt so tired. I just felt like I couldn't keep my body afloat any more. As I started sinking I could hear the sound of the engine coming towards me."

Hassiem saw the black belly of the dinghy skimming across the surface of the water, and somebody leaning over the side.

"I saw the reached-out arm of my brother. As I reached up he grabbed me."

Hassiem had survived. But the shark had claimed his right leg below the knee.

In hospital, pondering his future, Hassiem was persuaded to try competitive swimming, and before long found himself breaking records in the pool.

Two years after losing his leg he was on a plane to Beijing to represent his country at the 2008 Paralympic Games.

"It was absolutely amazing," he says. After that he represented South Africa on numerous occasions, winning a medal in the 100m butterfly at the London Paralympics.

He believes he has the shark to thank for setting him on a new path.

Image copyright Achmat Ahssiem

"Resulting from the shark attack I've managed to go around the world, see different countries, and meet different people.

"And I thought, 'Hey, all of this stemming from this shark attack, somehow I have to give back to sharks.' And I decided to become a marine conservationist and shark advocate.

"As a child I always wanted to represent South Africa, and the shark gave me the opportunity.

"But at the same time it's given me a sense that sharks are in trouble as well. And who better to speak up for sharks than a shark attack survivor?"

Achmat Hassiem spoke to Outlook on the BBC World Service. Listen again on iPlayer or get the Outlook podcast.

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