Sharks have had some pretty rotten PR in the past 50 years. A report in The Times yesterday that the scalloped hammerhead shark is one of nine shark species to be placed on the World Conservation Union List suggests that the tide could at last be changing for these predators who, since the 1975 film Jaws, have been depleted by more than 90 per cent and are at risk of total extinction. Now one man is highlighting the plight of sharks in a film that he describes as “anti-Jaws”.

Sharkwater, released in the UK on Friday, is a documentary that has taken the film-maker Rob Stewart (pictured), six years to complete. “I set out to make an underwater movie with no people in it. But no sooner had I started shooting, I discovered long-line fishing in the Ecuadorian marine reserve in the Galapagos, the last sanctuary for sharks. Sharks were being killed and nobody knew about it,” says Stewart. “It filled me with rage. I spent the next six years trying to make a movie about it.”

Sharkwater is a high-octane conservation adventure with Stewart aboard the Sea Shepherd Conservation Society’s Farley Mowat, an activist's vessel that rams poachers, getting arrested by the Costa Rican Government for attempted murder, uncovering multimillion-dollar shark fin rings, getting shot at and running from the Mafia. “My dad said the worst day of his life was when I called him from hospital and said I might lose my leg to flesh-eating disease.”

An increasing demand over the past 20 years for shark fin soup from the growing middle classes of China has led to the rise of barbaric methods such as finning (the fins are removed from live sharks and the fish thrown back in the sea immobilised and defenseless). The systematic removal of sharks from their ecosystems will have profound effects on the food chains below them, and have far-reaching conservational consequences for our own ecosystems.

“I wanted to make a movie that could make people see sharks through my eyes, to make them learn to love sharks, and to have a better understanding of how much we rely on the oceans and top predators such as sharks to survive.

“The most important lesson for me was to keep hoping and not give up. People mustn't lose hope because we have been in serious conservation situations in the past and figured it out. I strongly believe that we can do this again.”

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