Pest Wars: Return of the Cluster Fly

Also known as grass flies, the cluster fly (Pollenia rudis) is roughly 7 mm in length, has stripes behind the head, short yellow hairs on the thorax, and intermittent light and dark grey colouring on the abdomen.  They move a lot slower than most other species of fly found in the UK, “cluster” around lights and windowsills, and whilst they are not harmful to humans, or damaging to property, they are incredibly annoying.

As we begin November, we see the first signs of autumn, a reduction in temperature, and scout cluster flies looking for a warm, appropriate place to hibernate.  One fly alone wouldn’t be so bad, but once finding a suitable spot, the scout cluster fly’s invisible pheromone trail invites all his friends to come and join the slumber party.  In heavily infested buildings there may be as many as several thousand Cluster flies!  So now is the time to batten down the hatches and secure your property as much as possible against these annoying pests.

Here are Avon Pest Control’s Top Tips for Cluster Fly Prevention:

• Cluster flies are also known as attic flies, and they have gained this name for a good reason! They often enter your house via gaps in your attic, roof, and eaves and hibernate there. Check for any entrance points in these areas and seal them up with weatherproof sealant.  Also check for gaps around doors, windows, electric outlets, cable, wire and pipe openings and vents to prevent easy access to your home.  An added bonus will be that your house may stay warmer this winter!
• If you like to have your windows and doors open, install fly screens.
• Install a fine mesh over any vents.
• Clean up spillages and do not leave food on kitchen counters as this can attract flies.
• Whilst the Cluster fly will usually exit your property in early spring, they often return to their previous hibernation space, which can lead to annual infestations. Use a citronella scent in your loft which the scout flies may not like.  This could deter them from settling in your attic.

If you have already found cluster flies in your home, aerosol fly sprays can kill the pests it directly lands on, but sadly will not infiltrate cracks where the flies are hibernating.  For effective Cluster fly eradication, Avon Pest Control recommend contacting a professional pest control technician, who will have access to equipment and insecticides unavailable to the general public.

WARNING: Cluster flies are not the only uninvited guests that could be boarding in your loft.  If there is a chance you have Bats in your attic, insecticides must NOT be used by Law.

If you have found Cluster flies in your home, call Avon Pest Control today on 01926 632 929 or 01789 293 463 or click here for more contact information.  Our qualified, responsible technicians will happily discuss your pest problem and provide friendly, expert advice.

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