It could have been a scene from Jaws. A group of middleaged swimmers were taking a regular early-morning dip on an eerily overcast Monday at Perth's North Cottesloe Beach. Around 100 people were milling about, watching the gentle surf roll in and sipping coffee in the fashionable beachside bars.

"Is there something out there?" Ken Crew asked his friends as he ploughed along in the quiet of the shallows. A second later, in waistdeep water, his leg was torn off by a 16-foot great white shark. People screamed as the surf boiled red. Ken Crew was dragged to the shore, but lifesavers could only look on helplessly: the 49-year-old father of three had lost too much blood and died on the sand.

The fatal attack was the third off Australia recently. Six weeks ago, two south-coast surfers - a honeymooner and a 15-year-old - were hauled off their boards on successive days by great whites. Neither made it home.

After the attacks, many Australians were left wondering if their beachside lifestyle, of weekends spent picnicking, swimming, surfing and diving off their country's golden sands, was worth the risk. But there is life in the Australian dream yet. Stephen Leahy, the national lifesaving services manager of Surf Lifesaving Australia, reports "business as usual" around the country's coastline.

Down at the cherished symbol of Australia's good life, Sydney's Bondi Beach, the usual bobbing crowd, resembling a school of dolphins in their dark, sleek wetsuits, lines up in the sunshine to ride its famous waves. "It's something everyone worries about, but at the end of the day, if you want to surf, sharks might always be there," says Luca Ciano (22).

The sun has smelted deep creases on to the face of Bondi regular Gary Taylor. He has been swimming at the beach for "62 years, maybe longer" and he has only crossed the path of a shark once. But he says he wouldn't swim "down south" or over at Perth.

Most of Australia's popular beaches have shark nets, but these are not completely shark-proof. "A shark can swim in it or around it or over it," says Taylor, who saw two sharks being pulled from Bondi's nets last year. Australia's lifeguards also offer protection, sounding sirens if a suspicious fin is sighted.

Taylor and his mates remember the last fatal attack on a Sydney beach, in 1963. Statistically, the swimmers braving the seas around Australia are safe enough. "There are more than 60 million beach visitations in Australia every year and yet there are only three or four shark attacks. Not bad odds," reckons Leahy.

Taronga Zoo's shark statistician, John West, agrees. Before the latest three attacks, there had been just nine Australian fatalities in 10 years. But despite the drastic decline in the numbers of great whites over the past 20 years, people are still getting killed.

One theory gaining currency is that surfers suffer the consequences of mistaken identity. "Sharks, particularly whites and tigers, are opportunistic and inquisitive," explains West. "When a shark is swimming along and there is someone dressed up representing a seal - in a black wetsuit and fins - they test it to see if it's edible."

Others say sharks are being driven closer to the country's increasingly populated beaches by warmer waters brought about by climate change.

Mike Wescombe-Down, an experienced surfer and diver, is developing a pocket-sized version of the electronic shark deterrent used to protect triathletes from shark attacks in Sydney Harbour during the Olympics. He hopes to have the Walkman-sized pack, which emits sonar pulses to ward off sharks, on the market in eight months' time. He adds: "The pressure is on us to get this thing out quickly - 90 per cent of our phone calls come from worried parents."