Holy magnets Batman, does shark repellent actually work?
The NSW Government's $100,000 investment into trialling a sonar shark warning system and research into shark-deterring technologies is moving ahead.
The sonar system will be tested in aquariums to discover whether it can tell the difference between sharks, whales and other large sea creatures.
It will be rolled out to popular beaches across the state to alert lifesavers when a shark is swimming nearby, if testing proves successful.
Details of the shark repelling technologies being investigated remain murky, but there is no shortage of new products on the market already claiming to fill that role.
One of the most popular is the Australian-made Sharkbanz.
The wrist-worn band uses no batteries and emits a magnetic field which its creators claim repels sharks by reacting with the gel-filled electrical sensors around sharks' noses that are called ampullae of Lorenzini.
The science behind the product remains debatable, but testimonials from shark victims lend it some credibility.
Byron Bay chef Jabez Reitman survived an attack while surfing at Seven Mile Beach in February, suffering bite marks on his hip and a large chunk of flesh taken from his back.
He said he had been surfing at Shelly Beach in Ballina a fortnight earlier when he had a close encounter with a tiger shark.
Japanese surfer Tadashi Nakahara lost his life in an attack at almost the same place a couple of weeks after Mr Reitman's lucky escape.
"Luckily, I was wearing my Sharkbanz at the time. When the shark was about one and a half metre from me, it suddenly spun around so fast that I felt the slap of the tail and it rocked my board.
"In a flash it was gone. I'm convinced that the Sharkbanz deterred the shark, causing it to suddenly turn and vanish.
"Only days later, I forgot to wear my Sharkbanz, and was bitten in the right shoulder blade by a bull shark."
Optus is developing its own shark detecting buoys which use sonar to detect the animals and sends a message to the telecommunications company's satellites to alert lifesavers.
FIRST SHARK REPELLENT
During the Second World War, the US military created a chemical compound supposed to mimic the scent of a dead shark.
Divers and pilots were given the mixture in cake form, and it was used for about 30 years.
It was believed to have been partially effective, but not in all cases.