Ecosystem unbalanced: what a rise in shark numbers means for Australia's coast

The consensus among the Hunter, NSW, fishing community is that there are more and bigger sharks stalking the coast than there were just five years ago.

They are backed by dozens of social media posts featuring encounters with sharks, big and small, in the region's waterways.

Opinions vary on why, but one theory is that the ban on taking sharks greater than 1.5 metres in Queensland has had a knock-on effect.

The ban was introduced in 2009 as a conservation measure aimed at protecting vulnerable shark populations and promoting a sustainable marine ecosystem.

But it appears it is having unintended consequences, including boosting the overall shark numbers on coastal reefs along the East Coast.

"They wrecked the commercial fishery, and no one is taking them for food, and they are just coming further down the coast," Port Stephens Game Fishing Club president Troy Radford said

Mr Radford is among dozens of anglers who have had an increased number of large sharks stalking their boats ready to steal their catch.

"You actually see the sharks on the sounder, there's usually three or four of them and they just take the fish on you," he said.

"I just spent three weeks fishing up at Fitzroy Reef. You pull up, and within five minutes, the sharks are waiting at the back of the boat."

Hawks Nest spear fisherman Jake Nazer-Hennings agreed that shark numbers had exploded in recent years.

"The biggest one I have seen would have been five metres, but you regularly see 2.5 metre sharks," he said.

There has not been any major change to shark population policies since 1996, when great whites were listed as endangered and became protected in NSW.

But Nazer-Hennings, like Mr Radford, said he had concerns about the dominance of apex predators on the sustainability of the marine ecosystem.

"There's no balance in the ecosystem out there anymore," he said.

"You can't just protect one apex predator, it's ridiculous," he said."

A 2018 CSIRO found there could be as many as 12,800 great whites off the nation's east coast.

More than 700 sharks have been tagged by the state government. Scientists argue great white numbers have "stabilised".

The Australian Shark Attack File shows the number of recorded encounters between sharks and humans in Australia increased slightly between 1997 and 2017.

At the same time, the Australian population increased by 33 per cent.

The Australian Shark Incident Database shows the Bar Beach to Merewether stretch has recorded more attacks than any other part of the region's coastline with 10 attacks, including three fatal, occurring between 1907 and 2015.

The common area for shark attacks is Port Stephens coast and estuary system, with 18 occurring between 1898 and 2020.