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Mosquitoes • Back to main WNv page Types and Habitat Life Cycle   Types and Habitat Mosquitoes that Breed Around the Home Mosquitoes of some species can fly far from their breeding sites. Their presence in your neighbourhood does not always mean they have bred or will breed there. However, certain mosquitoes are considered domestic species because they breed around the home in small artificial containers such as birdbaths and eavestroughs.  Do all mosquitoes transmit the West Nile Virus? While there are many species of mosquitoes, the adult Culex pipiens mosquito (the common house mosquito) is the one most commonly associated with West Nile Virus.  Culex pipiens The northern house mosquito, Culex pipiens is the most common mosquito in urban and suburban areas of eastern Canada and British Columbia. The larvae can be found in artificial containers and ditches, and also in natural rain puddles and ponds. They thrive in water polluted with organic wastes. The females feed mainly at night mostly on birds, but will also bite people both outdoors and indoors. The tendency of Cx. Pipiens females (that are the wild hosts of West Nile Virus) to feed on people or birds makes them the most likely vector of West Nile Virus in North America, both from birds to birds and from birds to people. A closely related species, Cx. restuans, is found in eastern Canada and the prairie provinces. The larvae are found in similar sites, but the females less commonly bite people.  Ochlerotatus triseriatus The eastern tree-hole mosquito, Aedes triseriatus, another fairly common pest around homes, lays its eggs in tree-holes in many hardwoods. The eggs are laid just above the water line in the tree-hole. When rain raises the water level, the eggs hatch. Tires containing decomposing organic material, such as leaves, can stimulate this habitat and may be used by the eastern tree-hole mosquito as a breeding site. A single discarded tire in your yard can be the source of thousands of tree-hole mosquitoes over a summer. Other Species Larvae of Ochlerotatus atropalpus, which normally live in rock pools, and those of Anopheles punctipennis, which normally live in ponds and marshes, are sometimes found in artificial containers near dwellings. Females of these species will bite people, and may be pests around your home. Larger bodies of water on residential properties, such as ponds, snowmelt pools and grassy ditches, may form breeding sites for many other species too many to name here. Some of these species are significant pests; others never bite people.  Information taken from Health Canada: www.hc-sc.gc.ca/prma-arla The Life Cycle of Mosquitoes Because they are aquatic in their immature stages, all mosquitoes must have water in which to develop. The larvae cannot develop in tall grass or shrubbery, although the adults may be found resting in these spots during the day. Eggs The females of some mosquito species lay their eggs directly on the surface of water, in a raft of between 100 and 400 eggs. The eggs hatch in a day or so into larvae. Other species leave their eggs in a spot that will flood later, such as mud at the edge of a drying pond. Larvae Mosquito larvae look like worms, with no legs or wings; they are often known as "wigglers". They need to breathe air, so they hang from the water surface and feed there by filtering small particles from the water, but will dive to the bottom for short periods to feed or escape capture. They grow rapidly during this stage, molting four times during the next few days. On the fourth molt, they become pupae, where they form legs and wings. Pupae The comma-shaped pupae are also known as "tumblers" because they somersault in the water when disturbed. They cannot eat and must breathe air through two tubes on their backs. The mosquitoes grow inside the pupae. When they are ready, in about two days or so, they split the pupal skin and emerge as adults Adults The adult mosquitoes rest on the surface of the water until they are strong enough to fly, at which time they will search for something to eat. This entire life cycle from egg to adult can be completed in less than 10 days when the temperature is favourable. Click on this picture to view the Mosquito Breeding cycle