Signs of a Mosquito Infestation in Your Sydney Home

Four signs tell you mosquitoes have settled in rather than merely visiting. The first is a jump in biting, especially at dawn and dusk but often in daylight on the patio. The second is the thin, high whine near your ears at night. The third is adults resting during the day on shaded walls, fences and under the eaves. The fourth, and the one that proves they are breeding on site, is finding wriggling larvae in standing water.

The difference between visiting and breeding is the whole point. A few mosquitoes on a still evening can drift in from anywhere. Larvae in your pot plant saucer or blocked gutter mean the next generation is being made in your own yard, and the numbers will keep climbing until you break that cycle. The sections below take each sign in turn, then show you where to look and how to judge how far it has gone.

Bites that follow a pattern

One or two bites is nothing. A pattern is the sign. Aedes mosquitoes bite low and in daylight, so itchy welts around the ankles and shins while you sit outside point to container-breeders close to the house. Culex mosquitoes bite at dusk and after dark, so bites appearing in the evening and overnight point to larger, stagnant water nearby. Reading when and where you get bitten narrows down which mosquito and which water source you are dealing with.

The whine at night

The faint, high-pitched hum near your ears in bed is the wingbeat of a female searching for a blood meal. Hearing it more than the odd night, particularly if you wake up with fresh bites, means adults are getting indoors in numbers rather than one stray finding its way in.

Adults resting by day

Mosquitoes do not fly all day. They shelter in cool, shaded, humid spots and come out to feed at the edges of the day. If you disturb small mosquitoes off shaded walls, fence palings, under the eaves, in the garage or among dense low planting when you brush past, you have a resident population sheltering on the property, not passers-by.

Larvae in standing water

This is the strongest sign of all. Look into any still water and watch for a minute. Wrigglers are thin, comma-shaped larvae that hang just under the surface and dart down with a jerky flick when your shadow crosses them. Finding them confirms mosquitoes are breeding on your property right now, and it points straight at the water you need to deal with first.

Because mosquitoes breed in water, a good inspection is really a hunt for every pool of it, however small. Start close to the house where Aedes container-breeders live, then work outward. The four hotspots below catch the vast majority of Sydney backyard breeding, so check these before anything else. If you would rather have someone go through it with you, our mosquito control service includes a breeding survey as standard.

A light problem looks like this: you notice a few more bites on warm evenings, hear the odd whine, and when you check the yard you find one or two water sources with maybe a handful of larvae. At this stage clearing the water and knocking down the adults usually settles it, and DIY has a real chance of working. Acting now is the difference between a quick fix and a season-long fight.

An established infestation reads very differently. Biting is constant and starts to make the yard unusable at dusk, you find larvae in several separate water sources, and adults scatter whenever you brush past shaded planting or open the shed. When multiple breeding sites are active at once, the population renews faster than you can knock it down, and this is the point where a professional treatment that hits both larvae and adults across the whole property is the realistic way back. A yard backing onto a reserve, canal or wetland tips into this bracket faster because pressure keeps arriving from outside your fence.

Once you have confirmed the signs, work in order. First, tip out and clear every water source you found, because that stops the next generation and is the single most useful thing you can do. Second, deal with the adults already flying with screens, a fan on the deck and a skin repellent so you are not being bitten while the numbers fall. Our step-by-step guide on how to get rid of mosquitoes covers the full method.

A few things not to do. Do not reach for supermarket foggers as your main plan, because they knock down a few visible adults and leave the breeding water making more within days. Do not tip larvicide or household chemicals into a fish pond or rainwater tank hoping to fix it, since you can harm fish, block a drinking supply or use a product in a way it was never meant for. And do not empty a working ornamental pond, because moving water with fish is not the problem; still, neglected water is. If the biting is heavy or you have found several active breeding sites, the safe next step is a licensed inspection rather than guesswork.