By SALLY GORDON
A TRIAL of new electronic shark deterrent technology is yielding impressive results for the Clarence River ocean trawling fleet.
The device, produced by the South Australian company SeaChange Technology and known as the shark shield, can be used to protect divers, surfers and commercial fishing nets from predatory sharks.
Iluka commercial fisherman Barry Cason in the past year has been testing the shark shield on his cod-end nets in areas known to be infested with sharks.
He said that without the device fishermen faced losing around one-third of their catch in certain ocean areas because of shark attacks.
"Our big problem with sharks is that they attack the cod-end of the net and that causes all our catch to get out. It can be quite expensive and in some cases it's cost skippers their entire night's catch," Mr Cason said.
Clarence River Fishermen's Co-operative manager of marine services Brad Clark said the shark shield product for trawlermen involved a device the size of a woman's purse that contained a battery and had a three-to-four-metre chord attached that emitted an electronic pulse.
The device works by surrounding the user or net with an electrical field, of about eight metres, which impacts on special receptors in the snout of a shark.
The receptors are filled with an electronically conductive gel, which in turn connects to the shark's central nervous system.
The field generated by the shark shield inflicts an unfamiliar and unpleasant pulsing sensation on the shark should it continue to approach the device. Mr Clark said a range of SeaChange products was available at the co-op's Maclean and Iluka offices.
So far, the response to the new net-saving technology had been interesting, Mr Clark said. He was confident that down the track products would become widely used by Clarence trawlermen.
"It's still learning days, the two top fishermen have got them and a few others from down south. I think we are the only supplier in NSW at this stage."
The device has been praised for doing its job without harming sharks.