A pest control expert says winter will soon bring relief for homeowners under siege by plagues of cluster flies.
As the days become cooler and the trees turn colour, autumn can be an attractive season for humans - and insects.
Rural Wairarapa and Canterbury homeowners are under siege by a cluster fly plague, made worse by a wet summer.
Guaranteed Pest Control spokesperson Daniel Highman told Morning Report the flies were running rife across the country.
"We're encountering huge numbers of the fatty cluster fly and they are running rife through a lot of parts of New Zealand by the sounds of it from up north right down south."
'They are relatively hygeinic as flies go' - Pest control expert
Luckily cluster flies are not considered a "filth fly", Highman said.
"They are relatively hygienic as flies go, I don't believe they're actually a hazard to health unless they start dying in large numbers and they actually start rotting."
He said some people dealing with cluster fly infestations in their homes had to deal with layers of dead flies two to three inches deep on their floors.
Highman had heard of a number of people attempting to deal with cluster fly infestations. They had broken their vacuums in a futile attempt to clean up fallen flies.
He said it was best to take a preventative approach to pest control method.
"It's good to try and nip them in the bud before they end up becoming a real problem."
However, respite from the plague of flies is on the way with the weather cooling down as we head into winter.
"We've had a couple of frosts here in Canterbury, I imagine likewise with down south and possibly Marlborough Nelson, so a few more of the those frosts and that will definitely kill off the rest of the population that is in the surrounding pasture," he said.
Highman said the change of seasons appeared to be getting later and later with flies sticking around longer than previous years.