Throughout the world, there are over 3,000 species of mosquitoes. In Virginia, there have been 55 species of mosquitoes identified, of those we will typically deal with 15 to 20 in a season. Some of these species are very important in the disease transmission cycle, some are less important and some are not at all.
Of the ones that are important, some of the species of mosquito breed in containers and prefer to remain near these sites, which are often found in our own backyards. These sites include old tires, buckets, boats, house gutters, tarps, toys and etc. As mentioned above, a bottle cap full of water can provide the habitat for several mosquitoes that will then lay their eggs in the same spot and produce more - a continuing cycle (every 7 to 10 days). The ditches and woodlands produce different species, that again can be important vectors or not so important. In normal conditions, mosquito control districts can control these areas if they're aware of the standing water and have access. In addition, the trucks are more effective with these species as they may travel a distance in search of a blood meal.