MITIGATION: A white shark on the move.
MITIGATION: A white shark on the move. RamonCarretero

The science behind preventing shark attacks

GATHER round, people, and hear the tale of Shark No.28.

No.28 is a 3m white shark, on the move right now out there in ocean and, like most sharks, is a solitary long-distance traveller.

It was first caught, tagged and released on a smart drum line off Ballina at 3.30pm on May 5, 2016 as part of the Department of Primary Industries shark mitigation trials.

Since being released, No.28 has been to waters off Southeast Queensland, back past Ballina to South Australia, then past Ballina to Queensland again and now is in the deep ocean trenches off southern Western Australia, a journey of some 30,000km.

No.28 doesn't phone home much as he has to break the surface for his electronic tagging device to give off a location ping.

You can find out more about Shark No.28 and others of his species, as well as progress on the NSW Shark Management Strategy, when Simon Walsh delivers a Science Week presentation tomorrow at Byron Bay Library.

Mr Walsh, the DPI's shark strategy supervisor based at Wollongbar, will be giving an update on progress of the shark trial that began in 2016

About 500 sharks have been tagged and released off the smart drum lines with two shark fatalities.

There are currently 25 smart drum lines deployed off Lennox Head, Ballina and Evans Head. Contractors respond within 30 minutes when a shark is caught and the alarm is triggered.

"I will give an update on what we have learned regarding these mitigation strategies and also what feedback we have received from communities," he said.

"The next step will be to analyse what we have found and report to the community."

Mr Walsh wouldn't be drawn on picking a winner in terms of minimising shark encounters but highlighted the effectiveness of aerial surveillance and smart drum lines.

"Several surf lifesaving clubs have been doing drone trials, which appear to be very effective," he said.

"The smart drum lines are very effective at catching the target species and avoiding fatalities with non-target species."

This is a free Science Week presentation. It runs for 60 minutes, including a 20-minute Q&A.

Bookings are essential. Phone the library on 6685 8540.

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