Ramping up concern that something strange is going on in Australian waters are the locations of the latest attacks – Sydney's famed Bondi beach and its iconic harbour, where shark maulings are rare.
A surfer attacked at the city beach shortly before dusk on Thursday, just 36 hours after a navy diver was badly bitten during a military exercise in the harbour, became the sixth shark attack victim in two months.
He was pulled from the water by fellow surfers, including two French bodyboarders, who used leg ropes from their boards to apply tourniquets to staunch heavy bleeding from his arm, witnesses said.
The 33-year-old surfer's hand was "hanging by a small piece of skin" and he asked helpers to tell his wife he loved her, one said.
"When I first got to him, he was quite white and he looked like he was about to pass out," Sydney surfer James McIntosh told public radio.
"He said to me – this was when I first grabbed him – 'Tell my wife, Lisa, that I love her'. It was quite traumatic."
The victim also received attention from a number of off-duty doctors on the beach before being rushed to St Vincent's Hospital, where he was reported to be in a serious but stable condition after undergoing emergency surgery.
In the same hospital is Able Seaman Paul de Gelder, 31, whose hand has been amputated and who may lose his leg after he was bitten while taking part in a defence exercise near an upmarket residential area of the harbour on Wednesday.
The diver was the first swimmer attacked by a shark in Sydney Harbour for more than a decade, with the last fatal attack in 1963, while there have been no fatalities at Bondi beach for 80 years, experts say.
But John West, curator of the official Australian Shark Attack File held at Sydney's Taronga Zoo, dismisses claims that the number of attacks on humans is increasing.
"The human population is increasing and more and more people are going into the water, but there has not been a corresponding spike in fatalities from shark attacks," he told AFP.
"There is still an average of 1.2 fatalities a year over about the past 50 years – if anything the fatality rate for shark attacks is dropping in comparison to the increase in the human population.
"Humans are not part of the shark's diet, otherwise there would be nobody safe in the water."
West was speaking after three attacks on swimmers within 24 hours in early January – just two weeks after a snorkeller was killed by a shark.
Swimming was briefly banned at Bondi on Friday but the beach was later opened and a sole surfer was working the waves when an AFP photographer visited.
An ocean swimming race will also go ahead this weekend, organisers said, with competitors well protected by a fleet of accompanying water craft.
Calling for calm, Surf Life Saving Australia said in a statement on Friday attacks were still unlikely if swimmers used common sense and followed simple rules, such as avoiding the water around dawn and dusk.