More research key to best shark protection
UNIVERSITY of WA scientists say more funded research is needed to determine if West Australian great white sharks behave like their South African counterparts, following preliminary results on shark shield testing announced last week.
“It’s a very good question, and we can’t be absolutely sure because the conditions are different, as the water is much murkier over there, but we do know some South African great whites migrate to WA,” Oceans Institute director Shaun Collin said.
After seven fatal attacks in three years, Premier Colin Barnett gave the Institute $650,000 over more than two years to test the WA-developed Shark Shield’s electric pulses that interfere with sharks’ sensitive snouts, bright lights, loud underwater sounds and bubble curtains to deter attacks.
Initial results found lights were only effective on shark species most active at night, bubbles were effective for short periods but altering their composition was an improvement and needed more research and loud sounds, including killer whale calls, had a limited effect.
The scientists went to South Africa to test the Shark Shield because they found only one great white in 18 months in WA.
At Mossel Bay, 340km east of Cape Town, the shields were placed offshore up to 500m apart, with and without baits to attract sharks, before observations indicated the devices could deter 90 per cent of great whites.
Prof Collin said WA should now integrate its shark tagging programs with more field research over 5-10 years, continue “promising” bubble curtain work and start studying chemical shark deterrents.
Mr Barnett said funding into five other deterrent projects, including $300,000 for Shark Shield technology on surfboards, would continue but he doubted there would be a bubble curtain at Cottesloe Beach.
“I wouldn’t want children swimming around an electric fence,” he said, when asked about Shark Shield as a barrier.
Oceans Institute director Shaun Collin.