SHARKS have reached plague proportions in Lake Macquarie.
That's the view of sailor Chris Caldecoat who has renewed calls for lake swimming areas to be netted.
His comments coincide with the emergence of new pictures of a bull shark caught in Eraring Power Station's outlet canal.
Mr Caldecoat, of Sunshine in south-west Lake Macquarie, is a top sailor who owns Performance Sailcraft Australia.
The company is among the biggest dinghy builders in the world and makes Olympic Lasers.
"There are more bull sharks in the lake than I have ever seen," Mr Caldecoat said.
Hammerheads were abundant too, he added.
Mr Caldecoat said a rescue boat was used in a recent sailing race "to clear the sharks, so the boats could get off the start line without hitting a shark".
And adults were going out in boats before children's races to clear sharks.
"Everyone has to be conscious that sharks are out there," he said.
"The kids have training drills with capsizing.
"The adults circle around 100 foot out and that's enough to get rid of the sharks," Mr Caldecoat said.
People did not need to give up swimming and sailing in the lake, but should "get smart", Mr Caldecoat said, adding that he would swim close to shore but not across the lake.
Swimming baths should be netted, he said, as a way of keeping people conscious about the presence of sharks.
Additionally, it made people feel they could take their children swimming in safety.
Lake Macquarie Mayor Jodie Harrison said the council had asked the Department of Primary Industries for figures on sharks in the lake.
"Any decision the council makes on whether to net swimming areas must be based on evidence, rather than anecdote - no matter how well intentioned," Cr Harrison said.
The Newcastle Herald reported three weeks ago that a 2.4-metre bull shark was caught in the lake.
Ray Bain, of Kurri Kurri, took photographs of the shark being caught at the Eraring power station outlet.
Mr Bain said a fisherman used "a slab of mullet" to catch the shark.
"Four blokes pulled it up the bank," he said.
"After that I thought 'I'll never go in the water again'.
"I often walk in the water to get weed for bait."
Mr Bain said the fisherman took the shark home to eat.
Eraring environment manager Neil Williams said the lake was in a very healthy state.
"But with that comes the issue of high predators coming in as well," he said.