Female Cluster Flies lay their eggs in cracks in the soil, which hatch in three days. Unlike blow flies cluster flies are not associated with animal carcass, faeces, or woollens. When September arrives the … Sealing exterior cracks and holes on the outside of the house with caulk, especially south and west facing walls, can help to reduce the number of flies that find their way inside. The cluster fly is a parasite of earthworms and breeds outdoors in lawns and fields during the spring and summer. And the larvae of these flies develop in cocoons before hatching into adult flies. Once located, the earthworm is parasitized by the larva. Cluster flies frequently use buildings for winter shelter and can be the most common fly found indoors during the cool season. There is no easy remedy for cluster fly problems. This is because the larvae of a Cluster fly are an earthworm parasite that requires earthworms to grow into full adult Cluster flies. Cluster flies are very similar in looks to house flies, but they have a longer body and a yellow sheen on the thorax. Reference to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned. The exposed flies that are killed by such treatments are quickly replaced by others emerging from the ‘woodwork’. There may be four or more generations of cluster flies per season. The larvae, or maggots, of cluster flies develop as parasites in the bodies of earthworms. The spray should be applied by August 15 when the flies are beginning to congregate on outside walls. Once they’re in, they’re in and there is not much we can do about it. Earthworms are a major source of food for Pollenia rudis. To the layperson, cluster flies have no obvious characteristics that distinguish them from ordinary house flies. The life cycle of cluster flies starts in the spring when the fertilized female lays eggs on the soil near an earthworm hole. Cluster flies develop by feeding on earthworms. Because the larvae feed on earthworms, rather than on garbage, cluster flies are not as much of a health hazard as are house flies, which sometime carry diseases from place to place. Cluster flies are typically slow-moving. Pollenia species are also numerous in Australia and New Zealand (over 30 species); they are common in North America. Sounds strange, doesn't it? Cluster flies are large, slow moving, hairy, flies around 10-15mm with a dark gray to black non-metallic abdomen. Cluster flies are generally just considered a nuisance when they decide to move into your house in the fall. Control for cluster flies is exactly the same control used for all other fall home invaders. Cluster flies are actually a parasite of earthworms and thrive in areas where there is fertile soil. For questions about accessibility and/or if you need additional accommodations for a specific document, please send an email to ANR Communications & Marketing at anrcommunications@anr.msu.edu. Newly hatched maggots grab onto earthworms as they slither by and burrow into the worm to feed. The larvae are parasites of earthworms and the adults feed on plant sap, fruit and flowers. A vacuum cleaner is a pretty effective method of removing the sluggish, slow moving flies from the house as well. You can find cluster flies almost everywhere in the United States and Canada. They develop inside the gut of EARTHWORMS! Cluster flies prefer earthworms instead. They often emerge on warm days, and cluster at windows attempting to exit(hence the name). Michigan State University Extension programs and materials are open to all without regard to race, color, national origin, gender, gender identity, religion, age, height, weight, disability, political beliefs, sexual orientation, marital status, family status or veteran status. They lay their eggs in cracks in the soil and the eggs hatch in about three days. The cluster fly life cycle begins when a female lays her eggs in the soil in late summer or early fall. Aggressive and costly insecticide applications will only temporarily reduce the number of flies inside the home because it is nearly impossible to treat every hidden area that may be harboring insects. The poor worm does not usually survive the experience. The worm does not usually survive the experience. Cluster flies are related to blowflies, but feed on different foods. Adult cluster flies (Fig. Cluster flies like to lay their eggs on lawns, areas that have earthworms within the soil. You can find cluster flies almost everywhere in the United States and Canada, except for the Southern states bordering the Gulf of Mexico. Cluster flies are strictly parasitic on earthworms. During summer, cluster flies are active outdoors, where they are parasitic on earthworms. Adult cluster flies feed on pollen from plants, and females lay their eggs in the bodies of earthworms. They enter homes and other structures by squeezing through cracks around windows and doors, loosely hung siding, soffit vents, louvers and other similar entry points. The cluster fly is a parasite of earthworms and breeds outdoors in lawns and fields during the spring and summer. Masking tape applied over the opening will keep flies from entering through this route. They can be observed buzzing around yards just above the ground. And don’t expect miracles. Adult Cluster flies outdoors live close to the ground level, and feed on flower nectar, plant sap, fruits, and other organic materials. Besides being a tremendous annoyance, cluster flies are harmless; they do not feed or lay eggs during the winter months. 1) are slightly larger than the common house fly, Musca domestica . After that, they g… The adult flies emerge primarily in the autumn or even late summer. ZooKeys 971: 105-155. Cream coloured and shaped like an elongated wedge, cluster fly larvae feed on live earthworms for about 13 to 22 days before advancing to the pupal stage, which also takes place in the soil. They do not cause a health concern, because they do not lay their eggs in human food. Cluster flies complete 2 or more generations each summer. They do not transmit disease. The maggots of cluster flies have never been reared on any other food but living earthworms. Indoor aerosol insecticides are effective in killing exposed flies during the winter and spring months. Cluster flies are not ‘filth’ flies, do not eat anything in our homes and do not carry any diseases. Cluster Fly Life Cycle When a female emerges from hibernation (or is otherwise ready), she will lay eggs in soil where earthworms are active. They often emerge on warm days, and cluster at windows attempting to exit(hence the name). The female cluster fly will lay her eggs near where earthworms burrow, either in the soil or on dead and rotting leaves, and then when the eggs hatch, the larvae or maggots will seek out earthworms and feed on them until they are fully grown. Treating yards with insecticides to kill earthworms has not been shown to be effective in reducing the number of flies entering homes. You can rid your potted plant soil of earthworms by using organically made insect killers. Eight species are found in Britain and 31 in Europe. Adult cluster flies then mate and continue this cycle throughout the warm season, making the home garden quite literally a hot bed for reproduction. The cluster fly maggot is an internal parasite of earthworms and the flies are among the first to be active in the spring. The cluster fly maggots live on “planet earthworm” until there’s not much left for them to feed on, then pupate into their adult shape. Adult females lay their eggs near the openings of earthworm burrows. After hatching from eggs the cluster fly larvae find and burrow into the body of an earthworm to feed. Cluster flies have a widespread distribution. The cluster fly maggot is an internal parasite of earthworms and the flies are among the first to be active in the spring. That is the time they can be quite a nuisance as they enter homes for purpose of hibernating. Another option is hiring a professional pest control operator to treat the inside and outside of the house. This information is for educational purposes only. If you have potted plants, then cluster fly larvae will dig into the soil in search of earthworms.