In the blue waters off Cape Town, South Africa, a revolutionary experiment with an electronic barrier seeks to exploit the supersensitivity of sharks’ snouts to keep swimmers safe.
The technology has been developed by South African experts who invented the electronic “shark pod” for use by surfers and divers — now marketed by an Australian company — and could be applied globally if successful.
Years of research have shown that sharks will turn away when they encounter an electrical current. That fact has prompted this experiment on a much larger scale.
A 100-meter cable with vertical “risers” designed to emit a low-frequency electronic field was attached to the seabed off Glencairn beach for a five-month trial, starting in late 2014.
“If successful, it will provide the basis to develop a barrier system that can protect bathers without killing or harming sharks or any other marine animals,” says the KwaZulu-Natal Sharks Board, which developed the shark pod.
As for humans, “if someone touched the small part of an electrode that is exposed, they might experience a tingling sensation” but would suffer no harmful effects.
The barrier would mark a major shift away from the shark nets used in KwaZulu-Natal on South Africa’s east coast for the past 50 years, which also kill other animals and have been criticized as environmentally destructive.
Research has shown that a gel in the sharks’ noses makes them more sensitive to electrical currents than are other species. Ordinary fish and sea mammals such as seals and dolphins should not be affected by the barrier.