Witnesses say the shark is about 3 metres long and has been harassing fishers at Pulbah Island, in the lake’s south.

On at least two occasions, the shark breached out of the water next to a tinny.

Hunter district fisheries officer Warren Winter said he had received reports of a great white shark acting aggressively in the lake.

‘‘I am concerned, as other people are,’’ Mr Winter said.

‘‘It’s something we’re monitoring very closely and I take all reports very seriously – and they’re passed on up the chain.’’

Mr Winter said capturing the shark and towing it to sea was an option.

‘‘We have special lines made up that we could deploy, if we were confident it was in a particular area at a particular time,’’ he said.

‘‘We could catch it on a baited line, so it was hooked through the mouth.

‘‘The way we’ve designed this gear, we could tow it without killing it and the idea would be to tag it before releasing it.’’

Mr Winter said fisheries officers and a CSIRO official planned an attempt recently to catch the shark but the weather hampered them.

‘‘There’s no immediate plan to try and catch it but it is an option,’’ he said.

While white pointers are a protected species, they can be killed in exceptional circumstances.

‘‘We’d prefer not to kill it but killing it is an option,’’ Mr Winter said.

‘‘We could get special dispensation but the minister would have to sign off on that.’’

The Newcastle Herald published pictures in November last year, which shark experts said was a great white – less than three metres long – in Croudace Bay.

In July, pictures emerged of a juvenile great white in shallow water 80metres from Belmont 16ft Sailing Club.

Locals have speculated about these two sightings being the same shark and whether it had since grown and taken up residence at Pulbah Island.

With sharks known to swim in and out of the lake regularly through Swansea Channel, it was possible more than one great white was in the lake.

Mr Winter said: ‘‘If there’s one, there could be two – you just don’t know.’’

‘‘Everyone should consider this every time they go near the water,’’ he said.

‘‘We have a brochure called Shark Smart that people can get from our website.’’

Murrays Beach resident Lorenzo Corradi contacted the Herald to warn the public about great white sharks in the lake.

‘‘It’s been reported to authorities. I’m concerned they’ve said nothing in public about it,’’ Mr Corradi said.

‘‘A lot of people will be coming down here in summer who have no idea about it,’’ he said.

People are known to anchor boats around Pulbah Island – the deepest part of the lake – and swim there.

‘‘The shark has been there awhile and I’m concerned that, being a white pointer, it becomes territorial,’’ Mr Corradi said.

Fishers and boaties also reported bull sharks in the lake.

A 2.4-metre bull shark was caught in the Eraring power station outlet last year.

Sailor Chris Caldecoat said in October last year that there were ‘‘more bull sharks in the lake than I have ever seen’’.

Mr Caldecoat said a rescue boat was used in a sailing race in the lake’s south-west ‘‘to clear the sharks so the boats could get off the start line without hitting a shark’’.

Shark sightings in the lake are common but attacks are rare.

The last reported shark attack in Lake Macquarie was on October 14, 1946, in Swan Bay, Marks Point, when a swimmer was bitten on the leg, a Lake Macquarie City Council report said.

Some residents believe that the sharks in the lake have increased in number, type and size since commercial fishing was banned in 2002.

Residents campaigned last year for the council to reinstall shark nets at Belmont Bay but the council rejected the plan.

Installing nets at Belmont baths would have cost more than $45,000, with a $12,000 annual bill to maintain them.

The report said that people were in shark territory when they ‘‘enter open water’’.

‘‘Sharks are a natural part of healthy oceanic and estuarine environments,’’ it said.

No netted swimming areas were in the lake, except in Wyong Shire at the lake’s southern end.

Lake Macquarie Council provides 15 bathing spots marked with buoys that are vessel exclusion zones.

IT was dark, the water was choppy and fish were biting when fishers Tony Pockett and Troy Twyford first encountered a great white shark in Lake Macquarie.

The pair have since had several encounters with a great white, while fishing in a four-metre tinny off Pulbah Island.

Mr Pockett has seen twice and Mr Twyford three times a shark they believe to be about 3 metres long.

‘‘It’s nearly as long as the boat,’’ Mr Pockett, of Blacksmiths, said.

‘‘The last time we saw him was three weeks ago – he came right up to the boat and I could have touched him.

‘‘He was 500millimetres across the head – he’s big.’’

When the pair first saw the shark a couple of months ago, there was no moon and dark had fallen.

‘‘My rod went off and it took me ages to wind it in and when we finally got it up to the boat, we saw it was a jewy [jewfish],’’ Mr Pockett said.

‘‘My mate [Mr Twyford] scooped it and brought it into the boat – it was 90 centimetres.

‘‘We were standing up in the boat high-fiving.

‘‘We looked down and saw a chunk out of the fish, like a bite mark.’’

The jewfish had a few gashes, which they believe were shark nibbles.

‘‘Suddenly we heard what sounded like a car falling out of the sky and hitting the water, with white water everywhere,’’ Mr Pockett said.

The great white had apparently breached out of the water in a fit of anger because they had taken the jewfish.

‘‘It landed right next to the boat and started circling,’’ Mr Twyford said.

‘‘It was angry that night – if we fell in we were gone.’’

Mr Pockett said the shark ‘‘circled us twice, then was heading straight for us’’.

‘‘He came up beside the boat – he had a big white belly – eyeballed Troy and disappeared.’’

Mr Twyford said he witnessed a great white – probably the same creature – breach again off Pulbah Island in another fishing trip weeks later.

AN Aboriginal fisherman was reported taken by a shark in Lake Macquarie about 1880

Historians uncovered an incident, about 1900, of 18-year-old Nellie Boyd, who was taken by a shark while bathing in Swansea Channel

A 3.6-metre shark bit a dog in half at Toronto in January 1913

Douglas Blakemore, 15, suffered a severe cut on his left leg and buttock on October 14, 1946, in Swan Bay, Marks Point, after a shark bit him in muddy water. 

‘‘The whole thing jumped out of the water, like a marlin does,’’ he said.

Leave the water if a shark is spotted

Don’t swim too far from shore

Swim in groups

Avoid swimming and surfing when it’s dark or during twilight hours

Avoid murky water and water with effluent or sewage

Avoid areas used by recreational or commercial fishers

Avoid areas with signs of baitfish or fish-feeding activity and watch for diving seabirds

Do not rely on dolphins to indicate the absence of sharks – they often feed together

Avoid having pets in the water with you

Source: Shark Smart brochure – NSW Department of Primary Industries