This year, about 10,000 of the estimated 40,000 mammals have remained at their Lake Macquarie camp.

The stragglers could be delaying their departure.

But Blackalls Park resident John Rose said alarm bells were ringing for locals.

“The worry is that they’re not going to go at all,” Mr Rose said.

That’s a major concern for his neighbour, Lorraine Harvey, whose property in Fennell Crescent is next to the council-owned land where the flying foxes live.

The colder weather has brought Ms Harvey little relief from the around-the-clock torment of the noise, smell and physical damage caused by the flying foxes.

Ms Harvey said she moved to Blackalls Park seeking privacy, to indulge her love of birds and nature, and for the tranquillity.

All have been taken from her by the flying foxes.

The problems they cause impact on many aspects of her life.

“The smell from their faeces is just overpowering,” she said.

The smell made meal-times challenging, and eating outside impossible.

“Their faeces cover everything.”

She won’t get the car out when they are flying around. And she puts plastic gloves on to collect the Sunday papers off her lawn.

Ms Harvey said the camp had become an unlikely attraction for people, especially children, who now walk through the council land next to her house to disturb the flying foxes to watch them take flight.

Ms Harvey said authorities did not know enough about the health impacts of flying foxes on humans, nor the local ecosystem.

“It’s definitely a health hazard, but what about the impacts on the runoff from their droppings into Stoney Creek and into the lake?”

The fact the droppings had stained and corroded her letterbox, external walls and garden furniture was an indicator of the danger, she said.

And then there’s the noise.

The sound of the flying foxes in February and March was so intense Ms Harvey took to wearing earplugs in her efforts to sleep.

“My grandchildren don’t want to come here. It’s horrible,” she said.

Ms Harvey said the time had come for local authorities to take action.

She said methods proven elsewhere on the east coast could be employed to relocate the flying foxes “a few kilometres” and possibly to the Watagan Mountains.