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Four shark bites in 48 hours spark alarm
Australia's east coast has seen an extraordinary surge in shark incidents, with four bites reported within two days-three of them in a 15-kilometre stretch near Sydney. The events have reignited calls for shark culls, though experts warn such measures are ineffective and misguided.
Timeline of attacks
On 18 January, a 12-year-old boy suffered critical injuries after a shark bite in Sydney Harbour and later died. The following day, an 11-year-old's surfboard was bitten at Dee Why Beach, hours before a man was attacked at nearby Manly and hospitalized in critical condition. A fourth incident occurred on 20 January, when a surfer sustained chest injuries after a shark bit his board 300 kilometres north of Sydney.
"This is the closest-both in proximity and time-series of shark bites I've seen in 20 years of research," said Chris Pepin-Neff, an associate professor of public policy at the University of Sydney.
Environmental factors behind the surge
Experts attribute the recent spate of incidents to a combination of environmental conditions. Heavy rainfall-127 millimetres in 24 hours, Sydney's wettest January day in 38 years-created ideal conditions for bull sharks, which thrive in warm, brackish water near river mouths and estuaries.
"Bull sharks love river mouths and estuaries, so the freshwater flooding off the land was perfect for them," said Rebecca Olive, a senior research fellow at RMIT University.
The runoff likely flushed sewage and nutrients into coastal waters, attracting bait fish and, in turn, sharks. Pepin-Neff described the situation as a "perfect storm," with low-salinity freshwater triggering a "biodiversity explosion" near shore.
Rising incidents or better reporting?
Official data shows shark bite incidents in Australia have increased from around eight to 10 annually in the 1990s to mid-20s per year in the 2010s. However, experts argue this rise reflects improved data collection and human factors-such as a growing coastal population, increased water sports participation, and thicker wetsuits enabling longer ocean exposure-rather than more aggressive sharks.
"The number of encounters is higher because more people are in the water," Pepin-Neff said. "But the rate doesn't match the increase in ocean activity."
Olive noted that given the millions of daily ocean users, shark bites remain rare, and fatalities even rarer. She suggested heightened visibility-through drones, media coverage, and reporting systems-may distort perceptions of risk.
Calls for culls rejected by experts
The recent incidents have amplified demands for shark culls, typically involving nets or baited drumlines to kill sharks near beaches. Experts, however, dismiss the approach as ineffective and ecologically harmful.
"I'm strongly opposed to culling sharks to maintain an illusion of safety," Olive said. "It doesn't work."
Pepin-Neff added that culls fail to address the root cause: attractants in the water. "Killing sharks in Sydney Harbour won't help if the attractant remains and other sharks move in," they said.
Rethinking human-shark coexistence
Experts advocate for greater awareness of shark behaviour and environmental triggers. Individuals can reduce risk by avoiding swimming after heavy rain, while councils could expand shark enclosures for safer swimming.
"We need to treat the beach like the bush-wild and unpredictable," Pepin-Neff said. "The ocean is never safe, and sharks aren't always dangerous. We're in the way, not on the menu."
Olive and Pepin-Neff emphasize that shifting public perception-from viewing sharks as threats to understanding them as part of a shared ecosystem-is key to safer coexistence.
