Wet conditions during the year and a recent spike in temperature means mosquitoes and midgies are out in force across the south-east as the region's councils band together on an ambitious spraying program.
QIMR Berghofer Mosquito Control Laboratory senior research officer Brian Johnson said the explosion in the irritating, and sometimes painful, insects came down to "basically, water and heat".
"We've had plenty of moisture lately and the past two weeks we've finally had some warm days and it only takes a week or two for the insects to respond to that," Dr Johnson said.
"The control measures we implement at the moment target mosquitoes in their larval habitat and it's the most effective means of controlling mosquitoes.
"Right now there are more efforts in freshwater mosquito control.
"A lot of micro-habitats are created in these wet conditions, so it's very difficult to target all areas and there will be some areas that can escape."
Queensland Museum entomologist Chris Burwell agreed that insects and other animals had lived through "three fantastic years".
"Not in terms of floods, but … lots of rain means lots of plants and insects," Dr Burwell said.
"The rain is just a signal that good conditions are coming.
"Typically, where we are the winter months are colder and not great for insects because they can't generate their own heat.
"The winter months are generally drier as well.
"The spring rains herald plant growth and warmer temperatures."
Task force targets mosquito problem
Brisbane City Council workers began targeting thousands of mozzie breeding sites last week in a bid to prevent a large outbreak after the most recent wet weather.
Lord Mayor Adrian Schrinner said there were 2,400 locations across the city that were being targeted by spraying.
"It was raining earlier this morning and obviously rain means puddles, which mean mosquitoes and, particularly right now, freshwater mosquitoes are breeding so we've got the teams out and about across the city," he said.
"At the moment we're doing it by ground and when there's a trigger for the saltwater mosquitoes we'll do it by air as well.
"The wetlands are areas we target, but there are locations right across the city [where mosquitoes breed], you'd be surprised."
With its two entomologists on staff, the council is leading the south-east Queensland mosquito task force, established to assist in the management of the Japanese encephalitis virus at a regional level.
"Some councils don't actually have dedicated mosquito-spraying programs so we're working with them because mosquitoes don't recognise local government boundaries," Cr Schrinner said.
He said the group's first meeting was held on Monday night.
A Logan City Council spokeswoman said "760 water holding sites" were being treated, while Redland City Council delivered "a year-round mosquito management program".
Midges descending on suburbia
Anecdotally, there have been plenty of complaints recently about the appearance of midges — tiny, biting, blood-sucking insects — in south-east Brisbane in areas which don't usually experience the critters.
Dr Johnson said he had heard cafe patrons complaining about the influx and said the ones hanging around backyards and bush blocks far from the mangroves were a species that thrived in moist, leafy areas.
"These are not the midges associated with intertidal zones," he said.
"These types breed away from the coast, in waterways in suburbia, or just some muddy areas and patches around properties.
"We've had plenty of moisture for them but now the heat has contributed to the population explosion."
Midges vs mosquitoes
As many living in sub-tropical and tropical parts of the country would attest, midge bites are more painful and trigger a bigger reaction than a mosquito bite, despite the insects being far tinier.
Dr Johnson likens the way a midge extracts human blood to a "dog licking out of a bowl".
"Midges have a mandible which are like little razor blades, and they cut the skin and have to lap up the blood," he said.
"It's kind of like a dog licking out of a bowl, and so they put a lot of saliva into the wound that's created."
Babies or small children, who weren't used to midge bites, would show a more severe reaction to the insect than adults, Dr Johnson said.
Unlike mosquitoes, midges were difficult to control with environmentally safe insecticides.
Dr Johnson said midges spent most of their life in the mud. He said that heavy chemicals would be needed to target them, a strategy which would have devastating impacts on the surrounding wildlife.
How to prevent biting insects
Cr Schrinner said while councils would continue to treat mosquito-breeding sites, residents could protect their homes, families and pets from mosquitoes in a few different ways.
"Council treat larvae before they become adult mosquitoes and leave breeding grounds – and we treat at every possible opportunity," he said.
"When adult mosquitoes are active, residents should use insect repellent, wear loose fitting, full-length and light coloured clothing, and limit the amount of time spent in mosquito-prone areas particularly at dusk and dawn to help reduce the risk of being bitten.
"Residents can prepare their homes during mosquito season by keeping their yards empty of any water-holding containers such as buckets, pot plants, saucers and bird baths.
"Make sure windows, and all openings on rainwater tanks, are screened; and ensure roof gutters are not blocked with leaves."
Dr Johnson agreed that breeding "source reduction" around homes was "all you can do" to limit mozzie and midge infestations.
"Aside from that it's really difficult," he said.
He said traditional repellents such as Bushman or Aerogard were effective, as were natural repellents such as citronella and eucalyptus oil, however these needed to be applied more often.
Dr Johnson also said while Aussies were used to being bitten by insects, the population should also adhere to a Slip, Slop, Slap-style campaign to ward against diseases carried by mosquitoes, and the general discomfort.
