Shark nets ineffective says expert

SYDNEY - For decades, swimmers at many city beaches have felt confident in the knowledge that a mesh net separated them from the predators of the sea. But those nets may be little more than a placebo, says fish expert John Paxton.

Dr Paxton, an Australian Museum icthyologist, says the idea that meshing keeps man-eaters away from surfing beaches is an illusion.

A shark net failed to save 21-year-old Sarah Whiley when she was fatally mauled on Queensland's North Stradbroke Island earlier this month.

Up to three bull sharks tore off both Sarah's arms and severely lacerated her torso and legs when they attacked her as she waded in shallow water at the netted beach.

On the NSW south coast at the weekend, four large sharks, including a five-metre great white, were sighted cruising close to swimmers.

McDonald's Aerial Patrol, which conducts patrols in the Illawarra and Shoalhaven regions of NSW and is seeking funding to resume them over Sydney, has warned that a fatal shark attack is imminent on one of the city's beaches.

Dr Paxton agrees, saying the faith the NSW Government has shown in the shark nets is about placating the public - and not saving lives.

"Forty per cent of sharks caught in nets are found on the inside," he said.

"The nets can't be right on the surface because of boats and swimmers so they're about two metres down, meaning sharks can swim over them and around the ends of them."

What Sydney, Wollongong and Newcastle swimmers may not have known is that between the three cities there are only 51 beaches with the moveable shark nets. And they are there for little more than nine days during each of the summer months.

More than 1300km of NSW coast is net free - all year.

Nets were first introduced off Sydney beaches in 1937, when shark populations were abnormally large and attacks numerous.

They were attracted to offal from the Homebush abattoirs, discharged through a sewage outfall at Malabar between 1916 and 1970.

Since the netting programme began, no fatal shark attack has been recorded on Sydney beaches, although a woman was killed by a shark at an unprotected beach within Sydney Harbour in 1963.

A spokeswoman for NSW Minister for Primary Industries Ian Macdonald defended the meshing programme, saying it was designed to alter shark migratory habits.

"Sharks are very territorial and the meshing prevents them from establishing a territory of their own so they won't come back to that spot."

But Dr Paxton said there was no scientific research to support this claim. But the nets were being installed at a huge environmental cost, with 35 marine animals being killed for every death of a potentially dangerous shark.

Nicola Beynon, from the Humane Society International, said the NSW government should fund the reintroduction of aerial shark patrols over Sydney. "Aerial patrols are a better safety measure than the current shark nets on ocean beaches which kill thousands of harmless marine animals every year."

KEEPING THEM OUT

* More than 1300km of NSW coast is net free all year.

* Nets were first introduced off Sydney beaches in 1937, after numerous attacks by sharks attracted to abattoir offal discharged through a sewage outfall at Malabar.

* Since netting began, no fatal shark attack has been recorded on Sydney beaches.

* NSW beach patrollers have warned that a fatal shark attack is imminent.

* Fish expert John Paxton said 40 per cent of sharks caught in nets are found on the inside.

- AAP