Mosquito Info

Over 40 different species of mosquito are found in Illinois. While each species has its own developmental habitat, all mosquitoes need water in which to pass their early life stages. Some mosquitoes lay their eggs directly on the surface of water while others will lay their eggs in areas that will eventually fill with water.

Once conditions are right, they hatch into larvae. Mosquito larvae undergo four stages of growth and development called instars. Larvae feed on organic material and microorganisms in the water and return to the surface of the water to breathe. Larval development may be as rapid as 5-7 days at high temperatures. After the larval stages are complete the larvae shed their skins and emerge as pupae. Pupae are very active and dive if disturbed. Pupae do not feed while they undergo metamorphosis to the adult stage. The adult mosquito emerges from the pupal skin and rests on the water’s surface until it has dried off and is ready to fly.

Both male and female adult mosquitoes feed on plant nectar, but only the female bites to get the blood needed for egg development. While some kinds of mosquitoes can live several months, the main nuisance mosquitoes we have in this area usually survive four weeks or less. Not all mosquito species can carry disease, nor are all mosquitoes vicious biters. Some kinds of mosquito never bite humans. Mosquitoes also vary in the distances they travel from the water they developed in. While some species will not stray more than a block or two from their source, other's flight range can be 20 miles or more. The great diversity between different species of mosquitoes makes their control more complex, requiring a variety of approaches and methods. A short description of the most common mosquitoes is below.

Floodwater Mosquitoes These are the mosquito you will most notice during the summer. The most common species is the Aedes vexans. They lay their eggs on low land prone to flooding. After rainfall, many will hatch, causing a tremoundous explosion in the mosquito population. These eggs will survive a long period of time(and over winter) if rain doesn't come. Although they aren't known to transmit West Nile Virus, they can transmit dog heartworm, making it important to keep your dog medicated.

They can have a great flight range of over 10 and even up to 20 miles. This means that even with a comprehensive mosquito control program in our area, following heavy rains other areas that lack sufficient control or preserve areas that treatment cannot be done will make a large population within our area of coverage possible. They are aggressive and active during the day.

West Nile Virus Vectors The common species in our district that can transmit West Nile Virus (WNV) is the Culex pipiens. These Mosquitoes lay their eggs on top of standing water in rafts of hundreds. They are most abundant during periods of low rainfall, meaning that containers of water have longer to stagnate and do not get washed out by rain.

They do not fly far from their breeding site, meaning that in order to minimize the risk of WNV in your area, reduce the sources of stagnant water on your property. Cover rain barrels, store containers upside-down, change bird baths, maintain swimming pools, dispose of tires, etc. Unfortunately, this is not done by all residents, meaning that even with a comprehensive mosquito control program, the population of these mosquitoes is always around. More details about these mosquitoes can be found on our West Nile Virus page.