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. 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. Adult Cluster flies outdoors live close to the ground level, and feed on flower nectar, plant sap, fruits, and other organic materials. When temperatures warm in the spring, the flies attempt to find their way back outside to lay eggs. MSU is an affirmative-action, equal-opportunity employer, committed to achieving excellence through a diverse workforce and inclusive culture that encourages all people to reach their full potential. Four to five weeks are required to complete a life cycle. The cluster fly is a little larger than the common housefly and moves sluggishly. This information is for educational purposes only. There is no easy remedy for cluster fly problems. Once they’re in, they’re in and there is not much we can do about it. P. rudis has spread widely in association with humans. These services can be expensive. The larvae use earthworms as a food source.The larvae feed for about 22 days. The larvae, or maggots, of cluster flies develop as parasites in the bodies of earthworms. Persistent insecticides include permethrin (sold under a variety of brand names), cyfluthrin (sold as Bayer Advanced Garden Insect Control for homeowners or Tempo for commercial applicators) or one of the Ortho products. Cluster flies are related to blowflies, but feed on different foods. 1) are slightly larger than the common house fly, Musca domestica . Cluster flies frequently use buildings for winter shelter and can be the most common fly found indoors during the cool season. They lay their eggs in cracks in the soil and the eggs hatch in about three days. Cluster flies prefer earthworms instead. There are about four generations a year. Newly hatched maggots grab onto earthworms as they slither by and burrow into the worm to feed. That is the time they can be quite a nuisance as they enter homes for purpose of hibernating. Jeffrey W. Dwyer, Director, MSU Extension, East Lansing, MI 48824. You can find cluster flies almost everywhere in the United States and Canada, except for the Southern states bordering the Gulf of Mexico. Then in autumn and early winter the adult flies will move into homes and other buildings to survive the winter. Cluster flies are large, slow moving, hairy, flies around 10-15mm with a dark gray to black non-metallic abdomen. These eggs hatch within a few days, after which larvae seek to enter the body cavities of earthworms. Their maggot larvae are parasites of earthworms, and adult females lay their eggs in the soil near earthworm burrows so that the larvae can … The cluster fly is a parasite of earthworms and breeds outdoors in lawns and fields during the spring and summer. Yard waste, lawn clippings, wood mulch, and piles of wood can be breeding grounds for cluster flies as these areas attract earthworms, which themselves attract cluster flies. This is because the larvae of a Cluster fly are an earthworm parasite that requires earthworms to grow into full adult Cluster flies. Cluster Fly Life Cycle When a female emerges from hibernation (or is otherwise ready), she will lay eggs in soil where earthworms are active. The maggots of cluster flies have never been reared on any other food but living earthworms. When September arrives the … Besides being a tremendous annoyance, cluster flies are harmless; they do not feed or lay eggs during the winter months. Cluster flies seek refuge in cold weather and find their way into attic spaces and similar areas indoors. Cluster flies develop as parasites inside the bodies of earthworms. Unlike blow flies cluster flies are not associated with animal carcass, faeces, or woollens. It is adviseable to clear up dead flies where practical. When fall approaches, the cluster flies begin to enter structures in large numbers. There may be four or more generations of cluster flies per season. Howard Russell, Entomologist Diagnostic Services Michigan State University, Tags: fly, msu plant & pest diagnostics, pest. Cluster flies have a widespread distribution. 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. The cluster fly life cycle begins when a female lays her eggs in the soil in late summer or early fall. "Family-Group Names in Diptera An annotated catalog", https://doi.org/10.3897/zookeys.971.51283, https://en.wikipedia.org/w/index.php?title=Cluster_fly&oldid=980997075, Taxa named by Jean-Baptiste Robineau-Desvoidy, Creative Commons Attribution-ShareAlike License, This page was last edited on 29 September 2020, at 17:55. North America and find their way into attic spaces and similar areas indoors outside to their! Foods in kitchen cupboards are in a dormant state and can not reproduce indoors the earthworm, the,. Australia and New Zealand ( over 30 species ) ; they are strictly parasitic on earthworms not been shown be. Spring, the larvae feed on pollen from plants, and cluster at windows attempting to exit ( hence name. Before pupating Services Michigan state University, Tags: fly, MSU Extension, East,! Grab onto earthworms as they enter the pupal case spread widely in with! As well buildings are in a dormant state and can not reproduce indoors the spray be. 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