Up to 7 metres of muscle and teeth, packed into an agile and streamlined body that can weigh in at 2250kg – this is the great white shark, one of the most infamous hunters on Earth. But the reality is that these sharks may disappear from our oceans altogether within the next 20 years. Their terrifying reputation is part myth, part reality, rooted in their instinct to hunt and kill whatever looks like a good prey animal … and that can include human beings. But how far is their killer-reputation justified? Are great white sharks really the blood-thirsty loners we imagine them to be?

The usual methods of getting close to great whites to study them closely and form impressions of their population cross-section include caged dives and diving with airtanks. But these techniques are now known to affect the sharks’ behaviour: the predators’ extraordinary electrical sensory systems react to the galvanic properties of metal.