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Unlike the house or blow fly, cluster flies are not disease carriers but are considered a pest due to the large numbers they are known to congregate in, hence the name – cluster.  When hibernating in window and loft spaces they will cause building damage from the large amount of fluid and faecal deposits.


Treatment can involve proofing, fumigation, spraying and the use of EFK’s (electronic fly killers) but regardless of treatment type, it is best to try and treat the problem during the months of late October and November when the flies cluster in the greater numbers before hibernating.


Left untreated, infestation will re-occur year after year but unlike other pests this may allow you to plan your control in advance.





The Common Cluster Fly (Pollenia rudis) is one of a number of species found across the UK.  They tend to be noticed in the spring as they come out of hibernation and again in the autumn when they begin to gather for the winter  Once a fly finds a suitable space then it will release a pheromone to attract any other flies in the area.  This can lead to 1000’s of flies hibernating in your loft, crawl and window spaces.


Interestingly, building selection is very specific and it is not uncommon for one house within a terrace to be infested whereas there is no such infestation on either side.  There is no link between the cluster fly and poor hygiene, just the suitable temperature, light and humidity conditions that create ideal hibernation spaces.



We’re here to help with your cluster fly problem.





Call Hemingford Pest Control on 07736 327808 or 01296 620490

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