How can we prevent shark attacks on the North Coast?
THE great white shark attack on teenage surfer Cooper Allen at Ballina's Lighthouse Beach on Monday has renewed calls about what more can be done to prevent further shark attacks on our coast.
Here, reporter Leah White looks at the main shark mitigation technologies and trials that have been planned, implemented or talked about for our region, weighing up the pros and cons of each.
Shark shield subsidies
AT HIS first Ballina Shire Council meeting, newly-elected councillor Phil Meehan will put forward a motion for the council to approach the State Government with a request to have electronic shark shields for North Coast surfers subsidised by 50%.
The technology Cr Meehan is putting forward is called Freedom + surf bundle, a joint initiative between Shark Shield and Ocean & Earth.
It uses a rechargeable battery in a specially-designed tail pad kicker to power the antenna electrodes which are like stickers on the underside of the board. The electronic field triggers muscle spasms in a shark's sensitive nose receptors, causing discomfort and resulting in the shark swimming away. And the devices can be transferred from one board to another.
The upside to this proposal is it directly targets the population most at risk of a shark attack - surfers - and is highly effective at reducing attacks. There's also no impact on the marine environment.
The downside is the cost of the government subsidising 50% of a $600 product per person. Restricting it to North Coast surfers could make it more financially feasible, however other areas may consider this unfair.
A Department of Primary Industries report also noted the electromagnetic fields could affect people with pacemakers and other heart conditions.
Helicopter aerial patrols
DURING weekends and school holidays, the DPI has commissioned aerial helicopter patrols along the coast from Byron Bay to Evans Head.
If the pilot spots a shark that poses a threat to surfers or swimmers, a call is immediately made to 000 and the local surf lifesaving club. It will also reduce its height to hover and either use a siren or loud speaker to alert beachgoers to the presence of the shark.
The aerial patrols have been very effective at spotting sharks and alerting people to their presence. The downside is it's an expensive method of shark detection and there can be hours in between patrols, leaving surfers and swimmers open to attack. It's also less effective if conditions are murky and the sky is overcast.
Shark listening stations
THE satellite-linked shark listening stations record the presence of tagged sharks swimming within a 500m radius of the listening station, providing near real-time updates of tagged sharks. There's currently 20 listening stations on the New South Wales coast, including at Byron Bay, Lennox Head, Ballina and Evans Head.
The listening stations feed information to the DPI's Shark Smart app which alerts users when a tagged shark is near a VR4G listening station.
Close to real-time information about the presence of tagged sharks at a popular beach is obviously useful in helping surfers make an informed decision about whether or not they want to surf at that location.
However, it cannot detect untagged sharks which still leaves swimmers at risk of attack.
BASED on a successful South African model, Shark Watch uses trained spotters and drones to scan the ocean looking for shark activity.
When a shark is sighted within close proximity to swimmers, a warning system will alert them to the presence of sharks and remain in place until the beach is given the all-clear.
As a volunteer organisation, Shark Watch NSW will be dependent on members' fees, donations and sponsorships to operate successfully.
While the program has been highly successful in South Africa, it does require a large number of volunteers - about four for each station not including relief volunteers. The maximum time an average spotter can work is one hour before spotter fatigue sets in. There are at least four spotter sites in consideration between Ballina and Lennox Head.
THE Mini Ripper drone is fitted with a video camera, loudspeaker and an emergency pod containing lifesaving equipment capable of being dropped into the ocean remotely. There's also the Little Ripper drone, which looks like a miniature helicopter and is sponsored by Westpac, and functions much the same.
Both drones carry a "marine pod" which includes a water-activated inflatable lifebuoy, a Shark Shield electromagnetic shark repellent, plus a whistle and sea anchor. The video cameras attached to each drone can be watched in real time for shark presence.
Each drone costs about $250,000 and would be operated out of surf lifesaving clubs.
They require training to operate as well as manpower to fly and monitor during aerial patrols.
The drones stay in the air for about two-and-a-half hours before they need to recharge and refuel.
The video footage is surprisingly clear.