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source: Metro UK
Shark shields are not a new invention and they haven’t always worked in the past, but there’s a new one on the market which apparently does – and it’s sure to excite professional water babies.
The Shark Shield Freedom 7 is a wearable electronic deterrent, worn on the ankle like a surfboard leash, with a 2.2m antennae that trails in the water.
The electronic currents emitted are said to over-stimulate the shark’s electrosensory system so they can’t feel the vibrations of objects – like you – in the water.
And it’s been tested as almost 100% effective on great whites.
The fact that [great] white sharks are implicated in the majority of fatal incidents globally suggests that a deterrent that effectively deters this species should be an important safety consideration for ocean users,’ said Dr Ryan Kempster, lead researcher on the independent study conducted by the University of Western Australia (UWA), Macquarie University, Flinders University and Oceans Research in South Africa.
They tested the device at great white hotspot, Mossel Bay in South Africa, according to Australian Geographic.
322 tests were conducted, using a baited canister attached to an active Shark Shield.
On every single first encounter, the great whites turned away at an average distance of 1.3m.
It’s not all good news though – researchers found that sharks started to get used to the shield.
Some sharks returned to approach again, and each time they got closer to the shield.
After several approaches, one encounter out of 43 saw a great white touch the bait canister. Some individual sharks approached up to 7 times, and the same sharks got 12cm closer on average each time. – though they never got closer than 0.9m.
And a shark can’t eat you from 0.9m away. Not even with chopsticks.
Only one shark was bold enough to touch the shield itself – but the prof says this could be down to the individual nature of that particular shark.
There was the question of whether the sharks in the study were too well fed to care about the bait, as the area has a healthy supply of slippery seals for them to chew on.
Still, news of the device’s efficacy will come as excellent news for surfers, who are sick of having to punch sharks – and luckily there’s a surfboard friendly version too.
In a 2012 study conducted by Flanders University and the South Australian Research and Development Institute (SARDI), researchers tested Shark Shield’s Freedom 7 device, which is typically wrapped around the ankle of the user and trails an antenna that distributes an electronic pulse. The study found mixed results that leaned on the positive side, with researchers concluding that the shark shield did indeed have an effect on shark behavior (it took the sharks longer to take the bait and deterred many of sharks from taking the bait at all) but “it did not deter or repel them in all situations nor did it repel all individual sharks.”
Read more at http://www.surfermag.com/features/anti-shark-devices/#MV3IBFSJtjC3FLEp.99