Once petrified at the thought of a deep-sea encounter with a shark, free-dive champion Pierre Frolla now travels the world to swim with these predators, describing them as majestic and much-maligned.

"As a child, I was terrified of sharks, like many of my generation who grew up with 'Jaws'. Today I am terrified of them disappearing," said the 38-year-old national of Monaco who has become a fierce campaigner for the toothy fish.

Frolla was speaking ahead of a Convention on International Trade in Endangered Species (CITES) meeting that decided in Bangkok on Monday to grant protected status to five shark species threatened with extinction.

About 100 million sharks are killed every year, mainly to meet a craving for shark-fin soup in Asia, and experts say about 30 species are at risk.

Between 1999 and 2004, Frolla was four-time world champion of free-diving, a sport in which competitors seek to dive deepest on a single lungful of air, without any oxygen bottle or other backup.

Frolla recounts how he battled with a phobia which he now considers to have been baseless.

"When I used to take part in free-diving competitions, I was afraid of sharks even though I had never seen one," he said.

This changed in 1999, when he encountered a bull shark during a dive off Reunion island and found it was "a lot more afraid than I was," Frolla told AFP.

And later, he came across an enormous Jaws-style great white in the shark-rich ocean around South Africa -- an animal he found "majestic" and awe-inspiring, the diver said.

Along with training to hold his breath under water, swimming with sharks has become an important part of Frolla's exercise routine.

He helps produce conservation documentaries and to find sharks for scientific research.

So as not to disturb the world's oldest predators, Frolla has strict rules -- no air cylinders and no protective cages.

"With the bottles, one makes bubbles and noise that disturbs the animals and they are more difficult to approach," he explained -- as well as making it harder to move.

And for his own safety, Frolla stays away from brightly-coloured diving suits, never goes down solo, and never turns his back on a shark.

"Sharks are curious, not necessarily very intelligent, but opportunistic," he explains.

Rather than being fearful man-eaters, sharks sometimes mistake humans for their natural prey, like seals or tortoises, and at other times unintentionally hurt surfers as they "mouth" them out of curiosity, say experts.

Activists like Frolla believe movies such as Steven Spielberg's 1975 blockbuster, in which a great white stalks beachgoers at a New England resort, gave the fish an undeserved, murderous rap.

In 2012, 78 shark attacks were reported around the world, of which eight were fatal, "which is far fewer than people who died from bee stings," Frolla told a recent oceanographic conference in Paris.

Sharks are in fact far more threatened by humans than the other way round -- even "Jaws" author Peter Benchley was a campaigner for the animals' protection.

According to the UN's Food and Agricultural Organisation (FAO), 90 percent of the world's sharks have disappeared over the past 100 years.

"I see a fewer and fewer sharks in the Mediterranean and on my last visit to New Caledonia I saw none," said Frolla of the diver's paradise in the southwest Pacific. "There has been a big decline since my first visit there 10 years ago."