White sharks are responsible for more recorded attacks than any other species. Photo / Getty Images
After a number of high-profile incidents in Australia, we examine the data on shark attacks across the globe.
Swimmers in Sydney have been urged to stay out of the water after three people were seriously wounded during a spate of shark attacks in New South Wales.
The four attacks happened within 48 hours of each other, leaving a 13-year-old boy in intensive care, a 27-year-old man with an amputated leg, and another man with lower limb injuries. A fourth person – another young boy – was miraculously unscathed after a shark bit a chunk out of his surfboard.
At least three of the sharks involved in the attacks are believed to be bull sharks, which are known for their aggression and often frequent shallow waters. With tiger sharks and great whites, they are one of the three shark species most frequently involved in attacks on humans.
The last fatal shark attack in Australia happened in November last year, three years after a British man was killed by a shark off a Sydney beach. However, deadly shark attacks remain uncommon in Australia and worldwide, and experts have suggested that murky water caused by usually high levels of rainfall in the area may be the reason behind this cluster of incidents.
Although they are most common in the US and Australia, shark attacks are, overall, very rare.
The Florida Museum of Natural History’s International Shark Attack File (ISAF) has global data on shark attacks that stretch back to the 1900s. Its most recent report lists 71 confirmed bites on humans in 2024, of which 47 were “unprovoked” – a decrease on the 69 unprovoked attacks recorded in 2023. Of those 47 unprovoked shark bites, four were fatal.
Unprovoked bites are defined as incidents “in which a bite on a live human occurs in the shark’s natural habitat with no human provocation of the shark”.
Provoked bites “occur when a human initiates interaction with a shark in some way”, such as “when divers are bitten after harassing or trying to touch sharks, bites on spearfishers, bites on people attempting to feed sharks, and bites occurring while unhooking or removing a shark from a fishing net”.
To put those figures into context, according to a National Geographic report, about 2000 people are killed annually worldwide by lightning, meaning you are 500 times more likely to die in a lightning strike than a shark attack.
Hippos and elephants each kill around 500 humans annually, crocodiles around 1000, scorpions about 3000, while around 400,000 people are killed by other people in a typical year.
In short, no.
The first decade of the 20th century (1900-1909) saw 37 unprovoked attacks, according to the ISAF database. This grew to 82 in the 1920s, 227 in the 1960s, 500 in the 1990s, and 803 for the period 2010-2019. Which might look alarming, on the face of it. But this massive increase can be largely attributed to better reporting, more people (the global population was 1.6 billion in 1900; it is 8 billion today), and more people spending time in the water.
Indeed, the average number of unprovoked attacks has actually been trending down slightly in the last decade, from 82 per year (between 2010-17) to 64 (2018-2023).
“Short-term trends show both fatal and non-fatal bites to be decreasing,” states the ISAF. “The total number of unprovoked shark bites worldwide is extremely low, given the number of people participating in aquatic recreation each year. Fatality rates have been declining for decades, reflecting advances in beach safety, medical treatment and public awareness.”
That said, the actual number of fatal shark attacks worldwide remains uncertain. In many developing coastal countries there is no formal method of reporting suspected shark attacks, so many incidents are unlikely to be confirmed or end up on the ISAF database.
The US has for a long time seen the most ISAF-listed attacks, and last year accounted for 28 of those 47 unprovoked bites. It was followed by Australia (nine). Despite shark-related incidents often being reported in Egypt, the ISAF only lists one unprovoked attack there in 2024, although this was fatal.
Australia’s higher rates of shark attacks can be partly attributed to the fact that all 13 shark species that have been known to bite humans inhabit its waters.
Additionally, reporting of incidents in Australia and in the US is simply better, while residents of both countries spend far more of their leisure time diving, surfing and swimming than most other nationalities.
Within the US, it is no surprise that Florida sees the most shark attacks. The state represents half of the US total.
In previous years, surfers and other “surface recreationists” (this includes water skiing, windsurfing, boogie boarding and rafting) have been most susceptible. Experts largely agree that sharks attack humans because of mistaken identity, and they have long pointed out the similarity in shape between a surfboard and a seal.
“People surf where there are good waves, and where there are good waves, there’s turbidity, and where there’s turbidity, there are often bait fish that attract sharks. The turbidity also reduces visibility in the water, making it harder for sharks to see. Some of them make mistakes,” says Gavin Naylor, director of the Florida Program for Shark Research.
However, in 2024 swimmers and people wading in shallow water fell victim to the most unprovoked bites, accounting for 50% of attacks. Comparatively, people surfing or partaking in other board sports accounted for 34%.
The great white’s fearsome reputation, it would seem, is well founded. The ISAF database suggests that white sharks are responsible for the most unprovoked bites, listing 351 (out of 949), including 59 that were fatal. Next up are the tiger shark, with 142 (39 fatal), the bull shark, with 119 (26 fatal), the requiem shark, with 51 (five fatal), the sand tiger, with 36 (none fatal), and the blacktip, with 35 (none fatal).
But the ISAF offers a note of caution: “Attacks involving easily identified species, such as white, tiger, sand tiger, hammerhead and nurse sharks, nearly always identify the attacking species, while cases involving difficult to identify species, such as requiem sharks of the genus Carcharhinus, seldom correctly identify the attacker.”
Furthermore, the oceanic whitetip is suspected to have killed scores of castaways in cases that are not included in any official statistics. Jacques Cousteau called the oceanic whitetip “the most dangerous of all sharks”.
It’s possible.
In Australia, scientists at James Cook University have warned that rising sea temperatures are creating conditions favoured by bull sharks, leading them to spend longer around Sydney’s coast during the summer than they did in the past. That, combined with people’s attraction to watersports in warmer weather, has been speculated to increase the chance of human-shark encounters.
A study published in 2018 and carried out by Dr Ken Collins, senior research fellow at the University of Southampton and a former member of the UK Shark Tagging Programme, warned that dangerous sharks including great whites and oceanic whitetips could be swimming off the beaches of Cornwall within the next 30 years thanks to rising sea temperatures. At least 10 new species are predicted to become regular visitors to Britain’s waters by 2050.
The study initially looked at sharks in the Pacific, which biologists noticed were staying for longer than usual off the coast of Australia. After switching his focus to the Mediterranean, Collins said that given many sharks now already migrate thousands of miles to reach Spanish and Portuguese shores, it would only take a slight change in water temperatures to encourage them further north, and into Britain’s seas.
Other factors are in play, however. “The sombre truth is that the world’s shark populations are actually in decline, or exist at greatly reduced levels, as a result of overfishing and habitat loss,” states the ISAF. “On average there are only six fatalities that are attributable to unprovoked shark attacks worldwide, each year. By contrast about 100 million sharks and rays are killed each year by fisheries.”
This article was first published in May 2023 and has been revised and updated.
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