Mosquitoes in Your Gutters: Why They Breed There and How to Stop It

Yes, wherever the gutter holds water. The Queensland Government's list of household breeding sites (opens in a new tab) includes gutters, and its advice is short: “Clean gutters regularly to prevent mosquitoes from breeding.” A clear gutter drains after rain. A blocked one holds water after the rain stops, and still water is what mosquitoes need.

Leaves are usually what does the blocking. Over time they pack down into sludge, and water pools behind it instead of running to the downpipe. Gum trees drop leaves all year, and palms keep shedding too, so gutters under them fill faster than you'd think.

It doesn't take much water, either. Brisbane City Council's mosquito fact sheet (opens in a new tab) says backyard mosquitoes “can lay eggs around your home in small amounts of stagnant water.”

Water spilling over the front of the gutter in rain is often the same blockage at work. Our guide to why gutters overflow covers the other causes.

Keep the water moving. Clean the gutters regularly, as the Queensland Government advises, and make sure rain drains out the downpipe instead of pooling. Then check the rest of the yard every week, because gutters are only one of the places that hold water.

A clean takes the sludge out. We clear the leaves, twigs and sludge from your gutters, then check that water runs along each gutter and out the downpipe the way it should. You don't need gutter guard to book our gutter cleaning service, and quotes are free.

If a clean gutter still holds water, it may have lost its fall (its slope) or started to sag. The flow check after a clean is where that shows up.

We clean gutters across Brisbane, the Sunshine Coast and the Gold Coast. In Brisbane? Our page on what fills gutters across the city looks at the trees in each part of town.

The Queensland Government says Ross River and Barmah Forest viruses are the most common mosquito-borne diseases (opens in a new tab) in Queensland. Others include dengue, Japanese encephalitis virus (JEV) and Murray Valley encephalitis (MVE). You catch them from the bite of an infected mosquito, which is why its advice includes cutting the number of mosquitoes around your home.

Dengue is a different story. “Dengue is not usually found in Australia,” the Queensland Government says, though outbreaks have occurred in parts of north and central Queensland. Brisbane City Council's fact sheet says the dengue mosquito doesn't currently occur in Brisbane.

Pets are at risk too. The council's fact sheet says dogs and cats can catch heartworm from mosquitoes.

We clean gutters. We can't tell you whether a bite has made someone sick. If you or anyone at home has symptoms, the Queensland Government says to protect yourself from more bites and see a GP straight away (opens in a new tab). Only specific blood tests can show whether an illness is caused by a mosquito-borne disease.

It depends on the species. In the warmer months, Brisbane City Council says a saltmarsh mosquito can go from egg to adult in five to six days, and each one can lay hundreds of eggs at a time. That's a wetland mosquito. The council gives no figure for the backyard kind.

The backyard kind is the container-breeding mosquito. The council calls it the hardest one to fight, because control “requires householders to be aware of breeding sites and remove or manage them.”

So that part's up to each of us at home. A gutter is one of those sites, and it's the one you can't see from the back step.

It can. The Queensland Government says that under the Public Health Act (opens in a new tab), you could be fined by your local council if you're breeding mosquitoes around your home. The page doesn't give an amount. A blocked gutter holding still water is one place they can breed, so keep it on your weekly check.

Councils do their own share. Brisbane City Council says most of its mosquito control is focused on wetland areas. The backyard mosquito needs each household to find and clear its own breeding spots.

Yes, through a gap you'd barely notice. Brisbane City Council's fact sheet says a gap the size of a matchstick head is enough to let mosquitoes into your tank to lay eggs. The Queensland Government says to check the screens and seals on your tank.

The government and council advice we've read is all about keeping mosquitoes out, with the tank sealed and the inlet and outlet pipes screened.

The gutters feed the tank, so they're part of the same job. Our guide to rainwater tanks and gutter guard covers tank screens and the checks Queensland Health suggests.

Not on its own. Gutter guard keeps the leaves out, which helps the gutter drain after rain. It can't fix a gutter that's lost its fall, though. Mesh won't make a flat or sagging gutter drain, which is why we check the fall before any mesh goes on. The weekly check still applies.

We fit aluminium mesh over your existing gutters, and every job starts with a free gutter clean. Our page on gutter guard for homes has the details.

For some homes, a yearly clean is the better buy. Our guide on whether guard is worth it covers when.