Mosquito Control in Your Home & Garden

Some Mosquitoes bite during dawn and dusk and a few hours into the night - for example the aptly named Culex molestus, a serious indoor domestic pest in Australia (but which doesn’t spread diseases). On the other hand, some Mosquitoes actively bite during daylight hours - for example Aedes aegypti, the vector of Zika virus, yellow fever, and dengue fever. We have the Aedes aegypti mosquito in Australia and we have had outbreaks of dengue fever begin in Queensland but it is not endemic, meaning the virus is not normally present.

Ross River Virus is the most commonly reported mosquito-borne disease spread in Australia and it occurs in all states.

When controlling Mosquitoes prevention is better than cure, and this is achieved by being observant. It is always best to control any pest when they first appear, rather than letting them build up into ‘plague’ proportions and then trying to control them.

Mosquito control is centred around the prevention of breeding and screening the adult Mosquitoes out of the house. See the section How to Prevent Mosquitoes Appearing.

To help ensure they stay out of the home, treat indoor areas and surfaces with Yates Home Pest Long Term Control Barrier Spray. Spray typical resting places including door jams, flyscreens, curtain rods and around ceiling mounted fittings. You can also spray outdoors, applying it to eaves, flyscreens and awnings.

There are about 300 species of Mosquitoes in Australia which make up the family Culicidae. The family is part of the larger insect order Diptera which also includes Flies, Midges and Gnats. The word ‘diptera’ is derived from the Greek words for two (di) and wings (ptera). Mosquitoes and their relatives have one pair of wings (i.e. two wings) while all other flying insects have two pairs of wings (i.e. four wings).

Adult

Adult Mosquitoes vary considerably in size depending on the species. Individuals within a species may also vary in size depending on the conditions their larvae encounter. Well-nourished larvae mean bigger female Mosquitoes capable of laying more eggs. Mosquitoes are delicate long-legged insects with scales along the veins and rear margin of their single pair of wings. Male Mosquitoes have ornate feathery antennae, while females have simpler antennae. Female Mosquitoes live for about 2-3 weeks, while males live for only a week.

Eggs

Eggs (about 0.5mm in length) are usually laid at night. Some common species cement their eggs together into floating rafts on water. Anopheles and Aedes species do not make egg rafts but lay their eggs separately. Saltmarsh Mosquitoes lay their eggs singly in mud or vegetation of saltmarshes which are inundated by flood tides.

Larvae

Larvae are usually pale and slender, and have a distinct head, thorax and abdomen. Larvae have a breathing apparatus known as a siphon through which they breathe air at the surface of the water. Most species hang vertically in the water but Anopheles Mosquitoes have short siphons and lie parallel to the water surface. Mosquito larvae are very active which leads to their common name of ‘wrigglers’.

Pupae

A non-feeding stage where pupae breathe through tubes known as ‘trumpets’ on the surface of the water. They are ‘comma’ shaped with an enlarged head and thorax and a thin tail. Pupae are called ‘tumblers’ because they can tumble down out of danger if disturbed.

Females lay their eggs on water or wet surfaces, as many as 50 – 100 at a time depending on the species. Mosquito larvae hatch from the eggs and usually go through 4 moults feeding on algae, bacteria and organic debris before turning into pupae. Adult Mosquitoes emerge from pupae onto the water surface. During warm weather the entire life cycle of common Mosquitoes takes as little as seven days.

A couple of insects may be confused with Mosquitoes – non-biting Midges and Crane Flies. These are superficially similar to Mosquitoes in that they are delicate long-legged insects. 

Non-Biting Midges (Chironomidae) are completely harmless and don’t have a long proboscis. They are the insects that swarm above trees and other tall objects on warm evenings. Non-biting Midges will enter houses if windows are not screened properly. It's when they land that you can distinguish them from Mosquitoes.  When Non-biting Midges land to rest, they raise their front legs. Mosquitoes raise their hind legs when they rest.

Crane Flies are often mistaken for ‘giant’ Mosquitoes. Adult Crane Flies don't feed on much at all, and some have short lives of only a few days. Crane Flies proportionally have much longer legs than Mosquitoes, don’t have a long proboscis, and rarely occur in numbers sufficient to cause alarm.

Some people are not affected by Mosquito bites, but for other people Mosquito bites mean red itchy lumps causing sleepless nights. When a Mosquito stabs her needle-like mouthparts into your skin she injects saliva containing anticoagulants to stop the blood from clotting while she is sucking it up. It’s through their saliva that some Mosquito species transmit diseases.

Research has found that some people are more attractive to mosquitoes than others. People with higher metabolic rates or those who have been exercising are more likely to be bitten. Some blood types seem preferable to others as well – sorry Type O people. Pregnant women also attract roughly twice as many mosquito bites as others.

No plants are adversely impacted by Mosquitoes. Mosquitoes are known pollinators of some plants where other pollinators are scarce – for example in the Arctic. Mosquitoes are also an important food source for other animals including Bats, Birds, Fish and other Insects.

• Mosquito wrigglers and tumblers in pot trays and other containers outdoors.
• Adult Mosquitoes roosting under eaves and other sheltered areas during the day.
• Bite marks on skin.

• Empty water from potential breeding sites such as pot plant trays, buckets, gutters, etc.
• Change water in bird baths at least once per week.
• Stock garden ponds with native fish that will eat Mosquito larvae. Try Pacific Blue-eye or Empire Gudgeon - not the invasive ‘Mosquito Fish’ Gambusia
• Check that screens on windows and doors are intact.
• Seal all gaps around doors and windows to prevent Mosquitoes coming in.
• Screen outdoor entertainment areas.
• Wear repellent and/or long-sleeved clothing to prevent Mosquito bites when outdoors.
• Contact your local shire or city council for Mosquito information in your area.