Have you ever noticed sluggish flies gathering around your windows or lights during cooler months? These are likely cluster flies, a common nuisance pest in many Australian homes. Unlike regular houseflies, cluster flies don’t breed in garbage or animal waste; instead, they enter homes in large groups, seeking warmth for the winter. While they aren’t aggressive or known to spread disease, their presence can still be frustrating and unhygienic. Understanding their behaviour and knowing how to manage them effectively is key to keeping your home comfortable and pest-free.
What You Need to Know About Cluster Flies in Australia
When it comes to cluster flies in Australia, they’re typically found in rural and suburban areas where earthworms — their primary food source — thrive. These flies are slightly larger and slower than houseflies, often appearing in attics, window frames, and roof voids during the colder months.
Cluster flies don’t pose a direct health risk, but their habit of congregating in large numbers can make them a nuisance. They leave behind greasy marks and droppings that can stain walls and curtains, and their dead bodies may attract other pests such as beetles or mites. While a few cluster flies aren’t dangerous, a large infestation can quickly become unpleasant and require professional pest control intervention.
Are Cluster Flies Harmful to Humans or Pets?
The good news is that cluster flies are not harmful to humans or pets. They don’t bite, sting, or spread diseases like other types of flies. However, they can indirectly cause discomfort and minor hygiene issues. Their droppings may contaminate surfaces, and their presence can be distressing for homeowners when they appear in large numbers.
The main concern with cluster flies is their persistence. They tend to return to the same overwintering sites each year, which means that once they’ve found a suitable location in your home, they’re likely to come back. This can lead to recurring infestations if preventative measures aren’t taken.
Why Cluster Flies Choose Your Home
Cluster flies enter homes seeking warmth and shelter during autumn and winter. Small cracks, gaps in window frames, vents, and roof tiles are common entry points. Once inside, they cluster in dark, undisturbed areas like attics, roof cavities, and behind walls.
As the weather warms, they re-emerge, often causing a sudden surge of activity indoors. Homeowners may find dozens of flies buzzing near windows as they try to escape the light. Regular maintenance and sealing potential entry points can help reduce the likelihood of infestation, but professional pest treatment ensures long-term results.
How to Get Rid of Cluster Flies
Managing cluster flies requires a combination of prevention and professional treatment. Start by inspecting your home for cracks and openings where flies could enter. Seal gaps around windows, doors, and vents, and ensure that attic and roof areas are well-maintained.
Vacuuming up dead or sluggish flies is an easy way to remove them, but this only addresses the visible problem. Professional pest control technicians use targeted sprays, residual insecticides, and dusting treatments to reach hidden areas where flies may be clustering. For more serious infestations, ongoing monitoring and seasonal treatments may be needed to prevent recurrence.
If you prefer natural methods, certain essential oils like eucalyptus and peppermint can act as mild deterrents. However, these are best used alongside professional services for lasting effectiveness.
Preventing Future Infestations
Once cluster flies have been removed, prevention becomes the next step. Regular pest inspections can help identify early signs of infestation before they become severe. Keeping your home well-ventilated and free of gaps helps reduce entry points.
Outdoor maintenance is also important. Since cluster flies lay their eggs in soil near earthworms, maintaining lawns and garden beds can help minimise breeding areas. Installing fine mesh screens on vents and windows can further prevent them from entering your home.
While they’re not inherently dangerous, ongoing prevention ensures your home remains comfortable, clean, and free from nuisance pests.
If you’re struggling with a persistent cluster fly problem or other household pests, it’s time to call the experts. M&R Termite Solutions provides safe, effective, and professional pest management designed to protect your home year-round. Our team specialises in identifying and treating pest infestations with precision and care.
Call us today on 0413 716 233 to book an inspection or request a free quote. Let us help you eliminate cluster flies for good and keep your property healthy, hygienic, and pest-free.