It's "extraordinary", says shark researcher Chris Pepin-Neff: four shark bites within 48 hours, and three of them within a 15-kilometre stretch of Australia's east coast.
On 18 January, a 12-year-old boy was taken to hospital with critical injuries after being attacked while swimming in Sydney Harbour. The next day, an 11-year-old's surfboard was bitten at Dee Why beach, hours before a man was attacked at nearby Manly and taken to hospital in critical condition.
Then, on 20 January, a fourth surfer "sustained a wound to his chest" after a shark bit his board some 300km (186 miles) up the coast.
"This is the closest - in both proximity and in time - series of shark bites that I've ever seen in my 20 years of research," says Pepin-Neff, who is an associate professor of public policy at the University of Sydney.
The rapid spate of incidents triggered local and international alarm, with dozens of beaches closed amid fear of further attacks. Predictably, calls for shark culls have gathered momentum and volume.
