| The
facts
That allowing any type of insect or rodent within your premises
or home will obviously be a nuisance and in some cases serious
illness, loss of business and in extreme circumstances,
legal and civil prosecution. The Cluster Fly is 6mm long
with a wingspan of 10mm, a largish fly with a distinctive
bristly yellowish and black marked abdomen, the thorax is
covered with yellow-gold hairs, large reddish compound eyes..
Cluster flies are found throughout the UK and their common
name refers to their habit of forming clusters when “hibernating”
- in often large numbers - in buildings. Whilst there is
a specific species of common cluster fly (Pollenia rudis),
there are other species of cluster fly and swarming flies
which have a similar hibernating nature and these may also
be involved in forming mixed populations of flies inside
suitable buildings. The life cycle of the Cluster Fly is
very much dependent on the prevailing weather conditions,
and in this country, two generations a year are usual but
in hot summers, up to four generations per year are possible.
Cluster flies are “field” flies and in summer
and early autumn they are of no consequence. However, as
the weather becomes cooler, they seek out shelter in nooks
and crannies in houses and other buildings. As the weather
becomes colder, they search for more protection from the
elements and may be seen in large numbers, particularly
in roof spaces, lofts, etc, sometimes with several thousand
flies clustered together.
Where do Flies live?
South west and mainly South facing buildings are favoured,
the flies will invade cladded buildings and silos, and will
enter roof spaces and voids via small gaps and crevices
in the fabric They will cluster on the exterior of buildings
in huge numbers prior to crawling into the harbourages,
in the spring the warmth revivers them and they start to
leave buildings in numbers. Eggs laid loosely on damp soil
and in leaf litter, larvae hatch after a week and seek out
earthworms, they bore through the wall of the victim's body.
After it has grown to full size it bores its way out of
the worm and pupates in the soil. Depending on the weather
two generations are normal but up to four are possible,
flies hatch from the pupae and live outdoors, they start
to enter buidlings in large numbers in late September onwards
into November when the temperature begins to fall.
Why keep Flies under control?
The cluster flies are the genus Pollenia in the blowfly
family Calliphoridae. Unlike more familiar blowflies such
as the bluebottle genus Phormia, they do not present a health
hazard because they do not lay eggs in human food. They
are strictly parasitic on earthworms; the females lay their
eggs near earthworm burrows, and the larvae then infest
the worms. However, the flies are a nuisance because when
the adults emerge in the late summer or autumn they enter
houses to hibernate, often in large numbers; they are difficult
to eradicate because they favour inaccessible spaces such
as roof and wall cavities. They are often seen on windows
of little-used rooms. They are also sometimes known as attic
flies.
Prevention & Control
Control methods for cluster and swarming flies are often
ineffective or incomplete. It is often impossible to keep
flies from entering premises. Indeed, it is likely that
in many premises used by cluster flies the areas or voids
used are difficult, if not impossible, to locate. The best
method of control is to prevent them entering the building
in the first place, especially by blocking any access into
cavity walls, e.g. replacing missing bricks, filling in
other holes, etc. Although proofing is seldom 100% successful,
sealing around window and door frames and other obvious
entry points can also assist in controlling their presence.
Cluster flies do not breed indoors and once they are inside
a property, control can be relatively easily achieved with
a range of insecticides and fly strips.
Treatment
Contact Paramite Pest Solutions
if you suspect you may have a problem and we can advise
you on the best course of action. A visit by our pest control
officer can be arranged. He will carry out a survey.
Paramite Pest Solutions will take all possible precautions.
Revisits will be made until the problem is cleared. |
