NPIPM:Drosophila melanogaster
Authors: Ashley Mueller, Buyung Hadi
Flies are one of the most recognizable pests in the home. While they can be a nuisance, some species are a cause for health concern. These medically important flies are capable of transmitting bacteria and other disease-producing organisms that can affect the human digestive system.
Flies undergo four developmental stages: egg, larval, pupal, and adult. Flies are attracted to decaying organic materials. Places in the home where they are likely to reside are near room-temperature ripened produce and seldom-used drains and sinks. Adult flies are primarily active during the day, so they are often noticed. Preventing and managing flies indoors requires proper food storage and good sanitation practices in the kitchen and regular cleaning of areas that could be optimal breeding sites.
Identification
Adult fruit flies (Drosophila melanogaster), also known as vinegar flies, are small, about 1/8 inch long, and they have red eyes. The head and thorax are typically tan while the abdomen is black or striped. When adults emerge from pupae, they are white but darken in color with air exposure. Larvae are worm-like and are yellowish-white in color.
Habitat
Fruit flies are often found near room-temperature, overripe fruits and vegetables and yeasty baked goods in the home. However, food is not a requirement for the presence of fruit flies. They can originate from other sources. They are usually found near moist, fermenting organic matter, which is the ideal location for laying eggs. In many instances, a rarely used sink, shower, bathtub, or floor drain with gelatinous film build-up are ideal breeding sites. Adults are capable of flying indoors through poorly screened windows and doors.
Life Cycle and Seasonal History
Fruit flies can be found in the home year-round, but they are very common during late summer and early fall. Adult females lay many eggs near the surface of fermenting produce or moist organic matter. In approximately 24 hours at room temperature, the eggs hatch. Tiny larvae emerge, and they feed on the surface. The larvae pupate on a relatively dry surface near the food source, and a few days later the adults emerge. The entire fruit fly life cycle is completed in approximately one week at room temperature. With enough food and ideal conditions, adults may live about 30 days.
Human Interaction and Urban Impact
Fruit flies are not an economically important pest, but they have potential to cause health concern. Although they do not bite, they are capable of transmitting bacteria and other disease-causing organisms to foods. In large numbers, they can also be a nuisance.
Prevention and Management Approaches
Because fruit flies are drawn to ripened or fermenting fruits and vegetables and yeasty baked goods, proper food storage and good sanitation practices in the kitchen are the most effective and efficient methods in preventing them. If a fruit fly problem already exists, begin by eliminating breeding sites. Some inaccessible breeding sites, such as a garbage disposable or unreachable drain, may pose a challenge. Pouring boiling water in these areas can be an effective option.
Trapping adult flies is another option. Creating a simple trap by placing a funnel over a jar containing a couple ounces of apple cider vinegar is effective for managing small populations. Pyrethrin-based insecticides can also be applied to eradicate fruit flies. Always use precaution and follow the label carefully before using any insecticide. Insecticides have a certain amount of toxicity to mammals; children and pets are especially at risk.
Other Online Resources
For information regarding labels of chemical control options, please visit NPIC MAPL
