The order Diptera (Flies) contains over 100,000 species worldwide. The public impression of this species is one of dirty insects with distasteful habits. This impression is reasonably accurate for many of the species of flies in close association with man.

Below are just a few species of flies commonly found in the United States that are either a nuisance, or have distasteful habits, and therefore are important to control.

House Fly

House Flies are found wherever suitable breeding condition exist. This is normally rotting vegetable matter or animal faeces. House Flies are highly mobile and are capable of traveling several miles.

Adult flies feed on a wide range of liquid foods that they suck up with their sponge tipped proboscis (mouth-parts). Alternatively they may eject saliva onto solid food, which when dissolved, can be sucked back up. This process results in drops of vomit being left during feeding and also darker specks which are an indication of the fly's almost continuous defecation.

House Flies are known to transmit enteritic diseases, intestinal parasitic worms and are implicated in the spread of typhoid and cholera.

Blowflies (Bluebottle, Green Bottle)

Bluebottles enter buildings readily to find breeding sites which is primarily on dead and decaying animal matter, preferably carcasses or meat offal. Although very common in the wild, Blue Bottles are also frequently associated with some human activities.

They are potential disease transmitters and particular pests of the meat industry and slaughter houses, commercial canteens, food preparation areas and even domestic kitchens.

Unlike Bluebottles, Greenbottles are seldom attracted indoors and rely more on dead bodies of animals and excrement for breeding sites.

Blowing, hence the collective term Blowflies, describes the depositing of eggs in clusters on any fresh or older meat, meat products, offal and excrement. Freshly killed animals and game birds will be singled out for blowing by the acute sense of smell of the adult female fly.

Fruit Flies

This family (Drosophilidae) contains over 50 species of very small and small flies whose primary common feature involves their liking for fermenting material, preferably of fruit origin. Some species prefer to feed on faeces and other excrement.

Fruit Flies usually breed on rotting vegetable matter, fruit, sour milk, beer and vinegar, and are very rapid breeders.

They are potential disease transmitters and are a nuisance in large numbers.

Cluster Fly

Adult cluster flies live harmlessly outside in summer, but may enter buildings ( usually roof spaces and lofts, but also through windows into rooms) in autumn to hibernate, sometimes in vast numbers, and may become a severe nuisance. Some buildings are infested year after year by cluster flies.

Large aggregations of cluster flies produce a sickly smell, and if warmed up accidentally or artificially during their hibernation, may emerge rather lazily and create some concern among people using the building.

Other species that have similar hibernating habits include the Autumn Fly, Green Cluster Fly, Yellow Swarming Fly and The Window Fly.

Houseflies go through 4 stages of development: egg, larva, pupa and adult. The entire life cycle can be completed in 7-10 days under ideal conditions. Adult females can lay as many as 2,700 eggs in 30 days but more commonly lay 350-900 in 5 or 6 different batches. The eggs which are laid singly but often appear in clusters hatch in 6 to 24 hours. The maggot remains in the breeding media for 4-10 days, feeding and growing. In wet breeding areas, full grown larvae climb to the surface or sides of the breeding media before pupating. There have been cases of the larva crawling a distance of 150 ft. from the breeding source in order to pupate. The pupal stage lasts 3-6 days. The adult female is ready to lay eggs 2 2 days after emergence and continues to lay eggs for about one month. Adult flies live from 30-60 days during warmer months. In Northern areas, some adults may survive indoors for several months. It appears that flies continue to breed all year in low numbers in heated buildings such as dirty restaurants or incinerator rooms. In the spring these flies disperse to other buildings and increase in numbers rapidly.