America's Mosquito Problem
 A female Culex species of mosquito is shown here laying her eggs. The Culex lay their eggs in a "raft" formation. Photo courtesy of CDC.
Mosquito Facts
Mosquitoes are insects belonging to the order Diptera, the True Flies. They are unlike other flies in that the mosquito wings have scales. These pesky little insects bite warm blooded animals and humans interfering with work and taking much of the enjoyment out of planned outdoor activities. Only the female sucks blood from animals and humans. The males have feathery antennae and mouth parts not suitable for piercing the skin. The principal food of mosquitoes is nectar or a similar sugar source, not blood. Blood becomes important to the female only because of the protein necessary to produce and lay her eggs.
The use of the word "mosquito" is apparently of North American origin and dates back to about 1580. The Spanish called the mosquitoes musketas and the native Hispanic Americans called them zancudos. Musketas means "little fly" while zancudos means "long-legged."
There are over 2500 different species of mosquitoes world wide. In the United States there are about 200 species. Each mosquito species has a two part Latin scientific name like Culex pepins (carrier of the West Nile Virus). The first part of the name is the genus name of a group of closely related mosquitoes and the last part of name represents a group that is similar in structure and physiology and capable of interbreeding.
Mosquito Life Cycle
The mosquito goes through four distinct stages of its life cycle: Egg, Larva (wiggler), Pupa (tumbler), and Adult.
Egg: The eggs are usually attached together to form a "raft" (around 200 eggs) although some species lay their eggs one at a time. When laid on water (normal place for most species) they float on the surface. The eggs hatch into larvae within 48 hours.
Larva: The larva (plural larvae) live in the water coming to the surface to breath. They shed (molt) their skins four times, growing larger each time. Most larva species have a siphon tube for breathing as they hang upside down from the water surface. During the forth molt the larva changes into a pupa. "Wigglers" live in water from 4 to 14 days depending on species and water temperature.
Pupa: This stage is a resting, non-feeding stage of development. The pupa is lighter than water and therefore floats on the surface. It responds to changes and tumbles with a flip of its tail toward protective areas. This is the time the mosquito changes into an adult. When the development is completed, the new adult splits open the pupal skin and the mature adult mosquito emerges. "Tumblers" live in water from 1 to 4 days according to species and water temperature. In the Culex species in the southern United States, this process takes about two days.
Adult: The newly emerged adult rests on the surface of the water for a while allowing its wings and body parts to dry and harden before it can fly. Mating and blood feeding does not occur for a couple of days after the adult emerges. Normal life cycle for species varies from as little as four days to as long as one month (some species even longer).
The female loves you! Here's why.
Only the female mosquito requires a blood meal. They bite animals (both warm and cold blooded), birds and humans. Male mosquitoes do not bite. Both male and female mosquitoes are primarily nectar feeders. Protein is essential for egg production and the female mosquito acquires that protein through blood sucking. For these female mosquitoes, human blood is seldom their first choice. Horses, cattle, smaller animals, and birds are preferred.
Mosquitoes everywhere! Why? Do the math.
The female Culex mosquito (carrier of the West Nile Virus) can produce up to 3000 eggs in her life cycle which is about one month. (300 eggs every third day for 30 days = 3000 eggs.) Approximately one half of those eggs will become female mosquitoes. Therefore, in the second month there could be 1500 female Culex mosquitoes producing 1500 more female mosquitoes each. In the third month that could be 2.25 million female mosquitoes. Do the math for six or seven months of mosquito season and you will see why we have billions and billions of blood sucking mosquitoes! Of course, all of those mosquitoes do not survive to bite us, but we all know that far too many do survive. Therefore, what you need is a Mosquito Free Zone around your home/or and place of outside activities.
Why do I get bit?
Stimuli that influence biting include a combination of carbon dioxide, temperature, moisture, scent, color and movement. Female mosquitoes do not travel far. Most female mosquitoes can only detect a blood donor from about 50 yards away. Many chemicals and compounds are emitted from the human skin and breath that mosquitoes can detect. The combination of these chemicals and compounds are probably why some people get bitten more than others.
Why you need a Mosquito Free Zone.
Since mosquitoes do not travel great distances to obtain food, they live close to it. They first find an attractive place to live - food, shade, moisture. All of these things can be found around most nice homes. They then make this their home and feed off the nectar available and use the near by humans and animals (your family and your pets) for their free blood meals so they can propagate their species.
Look at this! Ouch!
These two pictures are from a scanning electron microscope view of the tip of a mosquito's proboscis.
A "needle" emerges from the proboscis and enters your skin. The mosquito first injects anti-coagulant into your blood to thin it and keep it from coagulating (turning into a solid) in its stomach. It is this anti-coagulant that causes the allergic reaction in your skin, resulting in redness and itching.
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