Sydney surfers are steering clear of the ocean, haunted by a spate of shark bites that has left even experienced watermen deeply unsettled. Rob Harcourt, an emeritus professor who leads Macquarie University’s marine predator research group, knows the feeling firsthand. Returning from a winter surf at Bondi, he described how the city’s famed breaks have lost their appeal.
“A lot of my surfer friends are not going in,” said Harcourt, 65. “A lot of people are very nervous – they’re traumatised.”
The latest attack happened last Saturday, when 34-year-old Leah Stewart suffered catastrophic injuries from a suspected great white shark bite at a patrolled Sydney beach. She was between the flags in clear water in the middle of the day – conditions that experts say should minimise risk. Her family says she remains critical in intensive care after her arm was amputated.
Rising trend beneath the surface
While the recent cluster of bites has rattled Sydney’s beach community, it is part of a longer, sharper rise in shark incidents across Australia. Globally the US records the most shark bites; Australia ranks second. But whereas global figures are largely flat, Australia’s tally is climbing.
According to the Australian Shark Incident file, the country averaged 3.1 unprovoked incidents – bites and attempted bites, excluding provoked events or those involving spear fishers – each year in the 1950s. That number crept up slowly until the 2000s, when it reached 12 a year. In the current decade the rate has jumped to 21 annually.
Deaths have also increased. The average rose from 1.7 per year in the 1950s to 3.8 per year so far this decade. Improved emergency response times and the wider availability of tourniquet kits at surf life-saving clubs are believed to have saved lives. Over the past five years Australia has averaged four deaths a year; this year there have already been four, according to Dr Daryl McPhee, who studies shark bite trends at Bond University on Queensland’s Gold Coast.
Since 2000 there have been 59 confirmed fatal shark attacks in Australia, with 24 occurring after 2020, the Australian Shark Incident file shows. The profile of victims has also shifted. In New South Wales, swimmers were most often bitten at the start of the 20th century. By the 1980s surfers became the primary targets: between 2000 and 2019 there were approximately 60 incidents involving surfers, compared with just four between 1980 and 1994.
“The rising trend is consistent with what people are feeling,” said McPhee.
Why the increase? A complex web of factors
There is no single explanation for the rise, but researchers point to several interacting causes. “People just want to know why,” said Harcourt. “We don’t have a definitive answer. But we do know some things.”
One of the most significant is a warming ocean. Bull sharks are spending more time in the Sydney area as water temperatures rise, and tiger sharks also prefer warmer conditions. Research from Macquarie University has found that bull sharks are delaying their departure from summering grounds off Sydney by about one day each year, lengthening their residency. Warmer water can also alter shark behaviour, potentially affecting navigation, learning and interactions.
Meanwhile, populations of seals and whales – key prey for large sharks – have been recovering since hunting was stopped. “Swimming next to a seal colony probably puts you in greater risk,” said Harcourt, because a shark may bite a human to test whether it is food, mistaking the person for a seal.
Changes in fish distribution also play a role. As warming waters push fish populations poleward, sharks follow their food. Heavy rainfall can flush debris and baitfish into coastal waters, creating feeding opportunities, and murky water reduces visibility for both humans and sharks.
Human activity has grown too. More people are entering the water, and Australia’s population centres overlap with the habitats of the three sharks most often responsible for serious bites: great whites, tigers and bulls.
A review of shark bites identified 40 different factors that had been suggested as contributors – from the rise of board sports to the proximity of popular beaches to river mouths – but noted that most have little research behind them.
Despite claims from former prime minister Tony Abbott that there are simply more sharks in the water, the data does not support that view. New South Wales government figures on marine animals caught in shark nets show no significant changes over time. “If there was an explosion in shark numbers, we would expect to see a lot more caught in those nets,” said Harcourt.
Safety measures under scrutiny
Australia’s first shark nets were installed more than 80 years ago, but their effectiveness and environmental cost are now fiercely debated. In recent years governments have added other measures, including baited hooks that alert authorities when a shark is caught, improved safety information, drone surveillance and “listening stations” that warn beachgoers when a tagged shark is nearby.
Professor Corey Bradshaw, an ecologist at Flinders University who has studied these measures, says that when done well, public education, drones and personal electronic deterrents can reduce risk. But on shark nets he is unequivocal. “I think they are bullshit,” he said. “They’re an environmental catastrophe and there is no evidence that they reduce the incidence of shark bites. They should have been pulled out of the water 50 years ago.”
Drones have proved effective at detecting large sharks near beaches. SMART drumlines – baited hooks that alert authorities for tagging and relocation – have a lower mortality rate than nets but still pose entanglement risks. Personal electronic deterrents can reduce the likelihood of a bite, though their effective radius is limited. Shark barriers, which physically separate swimmers from marine life, have a zero bycatch record but depend on local conditions.
“As humans we have this innate evolutionary response to predators, and so we inflate the risk in our brains, even though the risk is extremely small,” said Bradshaw. “Then we do other risky behaviours because they’re familiar and we do them all the time. Like driving to the beach.”
McPhee said calls for shark culls, amplified on social media and by some high-profile figures, are misguided. “It’s an old colonial view that we can bend nature to our will,” he said. Because sharks are migratory, culling is unlikely to reduce bites in Australia.
Fear that defies statistics
Experts often point out how rare shark bites are, comparing them to deaths from lightning strikes, falling coconuts or – more pertinently – drowning. Last year 82 people drowned at Australian beaches. Yet these comparisons do little to calm public anxiety.
“We know it’s not helping,” said Dr Brianna Le Busque, who researches public perceptions of sharks at the University of Adelaide. “We talk about how rare bites are and that almost makes it feel even more random and that we have even less control.”
Le Busque said humans fear things they cannot control, and the seemingly inexplicable nature of many shark bites magnifies that dread. Her survey of surfers from around the world – mostly in the US – found they feared sharks less than the general public, even though they had more encounters. “A lot of them said these encounters were non-events,” she said. “Maybe because these encounters are not negative, that gives them an anchor point.”
According to a survey, 85% of Australians believe beaches cannot be made “100 percent safe” from sharks, acknowledging the ocean’s inherent risks. Still, the fear persists – and for now, many Sydney surfers are staying on the sand.
