A recent rise in the number of recorded shark sightings in Lake Macquarie does not represent an increased population of them in the lake, the NSW Department of Primary Industries says.
According to one of the region's well-known angling experts, the apparent jump in the number of sharks spotted in the lake is likely a result of more people reporting what they have seen to tracking organisations - increasingly prominent due to their social media presence.
There were five recorded shark sightings in Lake Macquarie in December, data from community-based shark reporting and alert organisation Dorsal shows - up from a total of five across the previous three months combined, and two in December 2022.
A bull shark estimated to be two metres long was seen near Pulbah Island on New Year's Eve, after a 2.5 metre hammerhead was observed near Murrays Beach on December 28.
Another hammerhead - this one believed to be 1.5 metres long - was found north of Belmont on December 19 following the sighting of a 3.5 metre bull shark on the western side of the lake on December 5.
The first recorded sighting for the month was on December 2. It was an unknown species believed to be about 2.5 metres long.
A Department of Primary Industries (DPI) spokesperson said there were "no indications of greater numbers of sharks in the Lake Macquarie region".
"Sharks are present in Lake Macquarie at all times of the year," the spokesperson said.
"Typically, these consist of a variety of sharks such as hammerheads, wobbegongs and small whalers, but also white sharks between May and December and bull sharks between December and May."
Jason Nunn, a long-time angling expert who owns Fishermans Warehouse at Marks Point, told the Newcastle Herald he believed the spike in recorded sightings was "a bit of a novelty".
"To me it's just because of the acceleration of tourists in town," he said.
"The hammers are always there and for me it's a good sign of a healthy fishery.
"A lot of us, as fishermen, see them [sharks] all the time."
Mr Nunn said several species of shark known to enter the lake including bull sharks, whalers and juvenile whites tended to swim deeper than surface-feeding hammerheads - making the distinctively shaped creatures easier to spot.
He said there were "quite a few" resident hammerheads that tended not to leave the lake.
"Why would you? You're not going to get chomped in half by a bigger shark and there's plenty of mullet and tailor around to eat," he said.
"It's the [sharks] you don't see that are really the ones you've got to worry about."
The NSW DPI says water users should take extra care in murky or dirty water, after high rainfall or floods, in areas where there are lots of bait fish and diving sea birds, and within 1km of a river mouth.