Marine scientists have warned against an expansion of shark nets along the New South Wales coast following another incident of a surfer coming into contact with a shark.
A surfer was knocked off his board by a shark on Tuesday morning at Shelly beach on the NSW central coast. The 40-year-old man suffered minor injuries to his left hand and took himself to hospital for treatment.
The incident follows a more serious injury suffered by surfer David Quinlivan on Friday. The 65-year-old was knocked off his surf-ski by a shark near Hallidays Point and suffered a severe bite to the bone on his left ankle.
NSW premier Mike Baird has said that the spate of attacks – there have been 13 shark incidents along the NSW coast this year – is “unprecedented,” “extraordinary” and will “require action”.
Asked about the expanded use of shark nets, Baird said: “Notwithstanding how difficult I find that personally, it’s something that we have to be open to because we have to keep this community safe.”
The NSW government has commissioned a review into the best way to deter sharks and has already launched a $250,000 shark-tagging program near Ballina following a rash of attacks there. The review will report on 18 September.
NSW currently deploys anti-shark nets at 51 beaches between Wollongong and Newcastle between 1 September and 30 April each year. The nets are sunk below the surface of the water in about 10 to 12 metres of water, within 500 m of the shore.
Marine scientists have warned that any expansion of this program would result in many dead animals without an improvement in public safety.
“The important thing to realise is that these nets aren’t a barrier, they are a culling device to reduce the population so much that they won’t interact with humans,” said Dr Dan Bucher, a marine ecologist at Southern Cross University.
“There are gaps that sharks can swim through, you can’t cover the whole beach area. The nets also tangle other animals, such as stingrays, dugongs, seals, dolphins, turtles and endangered species of shark such as grey nurse sharks.
“The problem is that no one wants to pull the nets out of the Sydney region and run the risk of fingers being pointed at them if there’s an attack. Once we got them it’s been difficult to get rid of them, which is why we don’t want more in there now.”
Bucher said great-white shark numbers have “plummeted” in the past 30 years, contrary to fears that there are growing numbers of the predators along Australia’s east coast.
He added that the recent attacks were probably a “glitch caused by localised conditions. A leopard seal washed up on Ballina’s beach yesterday. That’s an Antarctic species, it should be nowhere near there, so strange things are happening out there at the moment.”
Alternative technology to nets includes a planned upgrade to the shark shield program, which provides an electronic deterrent to sharks. There are other options, such as the installation of a “bubble shield”, which would fire a curtain of bubbles near a beach that sharks may not want to swim through, and a “smart” buoy that can detect sharks from their swimming patterns.
The NSW government has claimed success in the shark-net strategy, pointing out that only one ocean-goer has died at a netted beach since the program started in 1937.
Conservation group Sea Shepherd claims the nets provide a “false sense of security” because the overall number of unwanted interactions with sharks has stayed the same, or even increased, in netted areas.
Sea Shepherd said NSW government data shows that 16,746 marine animals became entangled in shark nets between 1950 and 2014. Hammerhead sharks are the species that have been caught the most, followed by stingrays and whalers.
