The unintended impacts of shark mesh was on show on Saturday, with a juvenile humpback whale becoming entangled in a net near Coolangatta on the Gold Coast. The calf's mother helped keep the animal near the surface long enough for a patrol to arrive and cut the whale free.

Another shark bite last week – the sixth since the start of 2015 for the Ballina-Byron area alone – was the last straw for Premier Mike Baird. On Wednesday, he explained his backflip, saying it was time to "prioritise human life over everything".

Only one fatality has been recorded in the state's 51 netted beaches since their introduction in Sydney in 1937, back in 1951. There have, though, been 33 so-called unprovoked attacks some serious ones.

"We need some sort of protection," said Richard Beckers, owner of Ballina Surf shop and a supporter of the nets.

Mr Beckers said he had cancelled $100,000 in orders after two incidents in as many weeks. Sales of body and surf boards have dived about 90 per cent as surfers head to beaches considered safer elsewhere.

Another local, who declined to be named, said the government was "playing Russian Roulette with our lives" by not acting to halt the attacks.

Until last week, Mr Baird – himself a keen surfer – had resisted calls for the nets. Instead, he heeded advice from scientists who argue there is little evidence nets alone make beaches safer while killing thousands of marine creatures over the years.

At Coolongatta Beach, the Saturday morning rescue of the four-metre humpback whale went smoothly, ABC reported.

The four-metre humpback was trapped by its tail at Coolangatta Beach.

Both the calf and mother "were very calm", Mark Saul, a spokesman for Queensland Boating and Fisheries Patrol, told the national broadcaster.

"Mum had just pushed into the nets slightly to help keep the calf up on the surface which she was doing quite well," Mr Saul said.

"After a few cuts...it swam away with its mother to the south, in good health and condition."

'Not based on data'

The NSW policy reversal "is a political decision – it's not based on data," said Culum Brown, an associate professor at Macquarie University. "The costs are well known and there's little to nothing in terms of benefits."

Existing nets are typically 150 metres long and about six metres deep, allowing plenty of space for sharks to get around, over or under them.

A parliamentary inquiry earlier this year recommended the Department of Primary Industries "move toward replacement of current shark meshing with more ecologically sustainable technologies".

Colin Simpfendorfer, director of the Centre for Sustainable Tropical Fisheries and Aquaculture at James Cook University, said great white sharks have been protected for two decades in a bid to reverse their population's steep decline.

"The whole point [of nets] is that they catch sharks," Professor Simpfendorfer said. "You are looking to reduce the abundance of sharks where people want to swim."

The 189 sea creatures caught in the existing nets in 2014-15 included 44 target sharks – whites, tigers and bulls – as well as harmless shark species, dolphins and turtles. Of these, 116 died before they could be released, government data shows.

Over the past century, the national annual deaths from sharks is 1.3 people on average, rising to two people during the past five years, according to Taronga Zoo's shark file. Australians make an estimated 100 million visits to the beach a year.

By contrast, five people died from dogs in 2013, with 44 killed by falling out of bed, the Australian Bureau of Statistics said.

"You're more likely to get killed by bees or by horses than by sharks," Professor Brown said.

'Killing nets'

David Wright, Ballina's mayor, remains opposed to nets that will damage the richest marine life in eastern Australia. "We call them killing nets."

Even Seneca Rus, the 25 year-old surfer bitten by a suspected great white shark on Wednesday, has mixed views on nets. "I'm not too sure which way to go with that one," he told Channel Nine, according to AAP.

Mr Wright said Premier Baird had assured him this week that he would look at  "smart nets", which send alerts when an animal is trapped. A boat can then be dispatched to free the creature if it's still alive.

Jim Abernethy, an American conservationist visiting Australia with National Geographic and Canon, said shark nets were "a way for politicians to make the public believe they are solving a problem".

Mr Abernethy, who has made a career out of diving close to sharks without a cage, warned that depleting numbers of "apex predators" threatened entire marine eco-systems.

"If we continue to remove them at an unprecedented rate, it won't be long before oceans fail," he said.

Perhaps the only benefit from nets may be psychological by making swimmers "more comfortable", Professor Brown said.

Efforts instead should be targeted at understanding better how sharks behave and devising ways to alert surfers and others in the water when there is a risk of a shark bite, he said.

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