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Australia was a global hotspot for fatal shark attacks in 2023, recording 40% of deaths resulting from unprovoked attacks, new data reveals.
The University of Florida’s International Shark Attack File collates statistics on shark attacks, finding 69 unprovoked incidents last year. These are bites that occur without any human provocation.
The release of the global data comes only a week after a woman was attacked while swimming in Sydney Harbour, adding to Australia’s tally for 2024.
The researchers say while the number of incidents was relatively consistent with long term trends, fatalities in 2023 were higher than usual.
“This is within the range of the normal number of bites, though the fatalities are a bit unnerving this year,” says author Gavin Naylor, director of shark research at the Florida Museum of Natural History.
Out of 10 fatal attacks internationally, 4 occurred in Australia. These include 3 deaths in South Australia and a further fatality in Western Australia.
Other deaths resulting from shark attacks were recorded in the United States (2), Bahamas (1), Egypt (1), Mexico (1) and New Caledonia (1).
Australia also recorded 22% of all unprovoked shark attacks.
Surfers (42%) and swimmers (39%) experienced most unprovoked shark bites, followed by snorkellers and divers (13%).
Flinders University shark researcher, Professor Charlie Huveneers is the lead author on a recently published paper investigating shark-human interactions in Australia and the effectiveness of mitigation measures.
Huveneers tells Cosmos the spate of shark bites occurring in South Australia in 2023 is not as unusual as people think. Similar series of incidents in a short time frame have previously occurred in other states (such as 2011-2012 in Margaret River in Western Australia, 2013-14 in northern New South Wales and 2018 in the Whitsundays in Queensland) and in other countries (e.g. Reunion Island, New Caledonia).
The emotional response to such incidents is understandable as these are tragic and traumatic events, he says, but it’s important that any decisions made in the aftermath are based on science and evidence.
While unprovoked attacks have been increasing worldwide over the last four decades, shark bites are decreasing in some regions and remain stable in others, reflecting the high variability in the risk of being bitten.
“There are a range of factors that can contribute to trends in shark sightings and shark bites. Some of these factors include human population growth, that a lot of that population is increasingly living in coastal areas, and that people in these coastal areas are also spending more time in the water,” Huveneers says.
Other contributing factors include habitat modification, declining water quality, climate change, weather patterns and changes in the distribution of sharks and their prey.
The variability and low number of shark-human incidents makes it difficult to assess the efficiency of mitigation measures statistically, he says.
Huveneers says there are generally 3 tiers of responses, which he calls the “3Ps” – perimeter, proximity and preventing bleeding. Together these strategies can reduce the risk of shark bites and injuries, although the only way to completely eliminate risk is to keep out of the water.
“Perimeter is a first line of defence. And the idea is to establish an outer ring of measures that maximise the space between sharks and people.” This might include things like swimming enclosures, aerial surveillance or early warning systems.
When sharks are in proximity, technologies like electric deterrents can reduce the risk of shark bites by about 60%, based on tests done on tiger, bull and white sharks, Huveneers says. These devices create an electric field pulse that can deter sharks, even when approaching at speed, but only work at close range – within a few metres.
Finally, survival can be improved by preventing bleeding. Bite-resistant material or wetsuits potentially playing a role in reducing blood loss or tissue loss when bites occur, he says. First aid and trauma training is also critical.
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