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Fly Control for Commercial Premises
What are lesser house flies?
Lesser house flies (Fannia canicularis) are small insects that thrive in warm, damp places. While they do not bite, they are a nuisance, especially in homes and farms with decaying organic matter.
They reproduce quickly, laying eggs in manure and waste, making them hard to control without proper cleaning and lesser house fly treatment.
Key characteristics
Lesser house flies have a grey thorax with faint black stripes. Females have a grey, rounded abdomen, while males have a narrower abdomen with pale yellow patches. A key distinguishing feature is that their fourth wing vein is not bent. They hover in mid-air and often circle around lights.
Appearance
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Adult — one-eighth to one-fourth an inch" in length. Thorax grey with three faint black stripes; female abdomen grey and ovoid; male abdomen narrow with pale yellow patches; 4th wing vein not bent.
- Larva — Pale brown, ovoid with whip-like protuberances around the edges.
The life cycle of lesser house flies
Lesser house flies have a rapid life cycle, allowing their populations to grow quickly in the right conditions. Eggs hatch within 24 hours, and larvae mature in three to 60 days, depending on temperature and food availability. Pupation lasts three to 28 days, with adult flies emerging after one to four weeks.
Seasonal behaviors of lesser house flies
Female flies lay eggs in moist, decaying organic matter like manure and compost. These flies are most active in warm months but can persist year-round in heated spaces such as barns.
Habitat and diet of lesser house flies
Lesser house flies thrive in environments rich in moisture and decomposing organic material. Their habitat and diet play a crucial role in their survival and reproduction.
Where do lesser house flies live?
Lesser house flies prefer areas with decomposing organic matter, such as manure piles, compost bins, and waste disposal areas. They can also be found in damp vegetation, decaying leaves, and poorly maintained trash bins.
What do lesser house flies eat?
Larvae feed on decomposing organic matter, breaking down nutrients to grow. Adult flies consume sugary liquids, fermenting fruits and vegetables, and damp surfaces with microbial growth.
Habits and behavior of lesser house flies
Lesser house flies breed in semi-liquid decaying organic matter. Unlike common house flies, they are not strongly attracted to UV light and doorways. Males have an irregular flight pattern, often hovering in mid-air or flying in circles near windows and ceilings.
Managing and preventing lesser house fly infestations
Keeping lesser house flies under control requires a combination of sanitation, monitoring, and targeted treatment methods.
Signs of an infestation
A lesser house fly infestation is often recognized by small, hovering flies indoors, particularly near windows or doors.
Other signs include larvae in decomposing organic matter, flies gathering around manure, and an increasing number of flies in warm conditions.
How to get rid of lesser house flies?
To effectively treat lesser house flies, remove their breeding sites. Keep areas clean and use fly traps. Cleaning up manure, compost, and waste helps break their life cycle. Sealing garbage bins and eliminating food waste prevents them from thriving. Sticky traps and UV light traps can help reduce adult fly populations. If an infestation persists, our fly control experts can provide long-term solutions to eliminate lesser house flies and help keep them away for good.
Frequently asked questions
The lesser house fly is smaller than the common house fly and has a distinctive hovering flight pattern. Unlike house flies, they are less likely to land on food but still pose a risk of spreading pathogens.
Lesser house flies are drawn to moist, decaying organic matter, manure, and humid environments. They prefer breeding in waste materials rather than directly seeking out food indoors.
The entire life cycle, from egg to adult, can take anywhere from two weeks to over one month, depending on temperature and environmental conditions.
They lay their eggs in manure, compost piles, and other decomposing organic matter. Proper sanitation and waste management are key to preventing infestations.
Other types of flies
Learn more about other common flies found in the US, including filter flies, house flies, and autumn flies.
Drain flies are small, dark-colored insects often found near sinks, drains, and sewage systems.
Autumn flies, known for clustering around windows in cooler months, invade homes seeking warmth.
Fruit flies are small, reddish-brown insects with distinctive red eyes, commonly found around overripe or decaying fruit.