Cluster flies like a ​number of insects have discovered that heated buildings are ideal for surviving the cold of winter. As the weather cools in late summer and early Autumn, the sun warms the southern and western walls of buildings. The warmth attracts these insects to buildings where they crawl inside cracks and stay there for the winter. This would be fine, but during warm winter days, some insects "wake up" and end up on the inside of the building.​

House Fly (Musca domestica)​

The house fly is the most common and ubiquitous fly on the planet, being found everywhere humans are found except possibly the coldest reaches of the Arctic and Antarctic. Because it frequents unsanitary areas, such as round rubbish and animal manure, this fly is considered a possible health risk and its presence indoors should be minimized.

Blowfly Blue botte (Calliphora vomitoria)

​ Green Bottle (Lucilia sericata)

These flies are extremely common and can be found one to a few at a time in homes or businesses during the warm summer months. They are attracted to buildings by food odours and also warm/cool air currents emitting through cracks around doors and windows or through doors propped open for ventilation purposes. The sudden appearance of dozens of blow flies or bottle flies within a building signals a potential dead rodent, bird, or other animal in the wall, ceiling, attic.

Control Methods