Manchester & Trafford Pest Control

Posts Tagged ‘Cluster Flies’

Cluster Flies in Manchester, Lancashire, Cheshire and Merseyside

Cluster Flies are a major pest in Manchester, Lancashire, Cheshire and Merseyside

The large, black, pesky flies that show up in bed rooms and on window sills from late autumn through early spring are a common household pest. These flies are known as cluster flies, a name that describes their habit of clustering in large numbers inside attics. Their abundance varies from year to year, possibly in relation to the amount of rainfall through the summer.

Cluster flies do not reproduce indoors, and home owners bothered by these pests do not need to fear the flies are “hatching” from a dead animal or other unpleasant material within the attic or walls. Cluster flies develop as parasites inside the bodies of earthworms. There are three generations of flies produced each summer, and the final generation of the season migrates to houses and other buildings during mid to late September. Casual observation of client reports suggests houses located on an exposed hill top or high ground are most attractive to these migrating flies.

The flies cluster on the warm sides of buildings in late summer during the day. When the sun goes down and the temperatures cool, these flies crawl into the building through cracks under the eaves and around windows or through gaps in the siding. Once inside and secured in a protected location, they remain in hibernation until warmed by heat from the heating system or the sun.

As the flies warm throughout the winter, and especially in the early spring, they come out of their cold temperature dormancy and begin sluggishly moving around. Their random crawling brings them into the house by way of electrical outlets, window pulley holes, and small openings around windows, mouldings and skirting boards.