He said he saw the shark about 10.30am on Sunday, January 19, while dozens of swimmers enjoyed the ocean oblivious to the fact the four-metre animal was making its way towards them.

Mr Alley said he contacted the surf club as soon as he landed to let them know there was a suspected great white in the vicinity.

"If you swim more than 50 metres off Hawks Nest Beach it's literally like playing Russian roulette," he said.

"After what I've seen in the last five years from the air, I just swim in the pool."

Bennetts Beach has been identified as a shark nursery by a recent report from the CSRIO.

The report explained that sharks spent 20 per cent of their time in the nursery near the surf zone of Bennetts Beach.

The report also identified Mungo Brush and Stockton as hot spots for concentrations of sharks. Satellite tracking showed juvenile white pointers occupied habitat in Port Stephens from close to shore to 120-metre-deep water.

A CSIRO statement said that while the frequency of encounters between people and sharks could be high in the area, the frequency of attacks was "very low".

Mr Alley believes consistent aerial patrols in areas of known shark hot-spots was the only way to effectively monitor sharks.

"The ultimate machine for spotting sharks is a helicopter," he said.

He said he was 100 per cent against shark culling and respected that the creatures were just moving around in their natural habitat.

"The odds of getting attacked are low," he said.

"I just want to furnish people with the information that they're out there."