As the six-month trial of the five nets introduced along the beach near Ballina draws towards a close, Mr Allen is back in the surf but doubtful the mesh – 150 metres wide by six metres deep – has reduced board-riding risks.

"I don't really know if they are doing anything or not," he says. "Definitely, some people have gained some confidence with the nets."

Locals say that confidence has had tangible benefits, with retail and hotel trade recovering strongly to possibly record levels during the long, hot season when almost all of the NSW coast notched its hottest summer on record. 

Some want more nets added and for the trial to be made permanent to ensure Nippers remain in big numbers and backpacking surfers keep getting bussed in from Byron.

It's a far cry from when the 30km stretch was dubbed the "shark attack capital" after accounting for 9 per cent of global shark encounters, including two deaths, Ballina mayor David Wright said.

The government is wary, though, not to declare the trial a success, and for other measures introduced as part of its $16 million Shark Management Strategy to help cut the risk of shark bites.

One reason is white sharks typically move south during the warmer months – and will be returning in greater numbers as whales migrate up the coast. Another is that attacks remain a risk – if a tiny one – as shown by the death earlier this month of 17-year-old surfer Laeticia Brouwer near Esperance in Western Australia.

"Fortunately there were no incidents of shark attacks along the NSW coastline during this period," a spokeswoman for the Department of Primary Industries said. "We have around six million people who visit our beaches in NSW each year, so protecting our swimmers and surfers along our vast coastline is a massive task."

Efforts to reassure the public are multi-pronged. During the NSW summer school holidays alone, helicopters clocked up about 93,000 km between Eden in the state's south and Tweed Heads.

The crews spotted 525 potentially dangerous sharks, with about a third of them swimming near bathing areas, prompting 78 water evacuations, DPI said.

Drone surveillance was also stepped up in the north and other regions such as Redhead, near Lake Macquarie, and Kiama. These devices picked up 46 shark sightings – more than half at Redhead alone – prompting eight evacuations but also a successful rescue of two swimmers swept out to sea at Kiama.

However, the value of the shark nets remains a sore spot with scientists stating privately that it is impossible to know whether their presence made any significant reduction in shark-bite risk – other than to kill some of the animals they caught.

So far the nets near Ballina have caught six so-called target sharks – whites, bulls or tigers – three of which were released alive after tagging. Another nine "potentially dangerous" sharks were caught, with only one surviving.

Other by-catch remains an issue, with 172 non-target animals including dolphins snarled in the nets, with 71 dying before crews arrived to release them during their once-daily visits.

Smart drumlines, which hone in only on target sharks, are viewed as relatively successful, catching 17 sharks with all but one released alive. Two grey nurse sharks were also caught and survived, DPI said.

For Cooper Allen, though, it's a case of "what happens, happens", and he just surfs when the waves are good, net or not.

Now fully recovered physically – save for a numb region around his thigh – the damage is mostly mental.

"I'm just always going to be on edge," he says, adding he tries to keep his legs "in the air" when out on the board. "You're never going to get it out of your head."