As the weather starts to warm up, it’s inevitable that we’re going to see more flies. Even though they’re a complete nuisance and we don’t want them near our food, most of us aren’t that bothered about the presence of the odd one or two.

Cluster flies on the other hand can be a different story. These insects tend to gather in large numbers which means an infestation is more likely and can be a bit scary, not to mention problematic.

Even though they like to make their way into our homes during late autumn, you’re unlikely to see them because they hibernate throughout winter. As the sunny spring days roll around however, they come out of hibernation. Cluster flies do sometimes mistakenly come out of hibernation early because of the central heating in our homes.

Because cluster flies gather in such large numbers, if you do have an infestation, you’re likely to be swarmed with them.

What do cluster flies look like?

Cluster flies are large and black and are very similar to house flies. It can be difficult to spot the difference between them because they tend to fly away as soon as you get near.

If you can get close or you spot any dead flies, have a close look before disposing of them. Cluster flies have yellowish golden hairs on their thorax and a prominent dark and light coloured chequered pattern on their abdomen. At rest, both wings overlap across the abdomen and physically, they tend to be slow and sluggish.

What are the signs of an infestation?

Because cluster flies are usually found in quiet, undisturbed parts of the home, it can be very difficult to know you have an infestation. Below are some of the more common signs they’re present however:

They can give off a sickly, sweetish odour if disturbed. If you notice a strange smell in your house, it could be a sign that they’re hiding somewhere

They sometimes leave tiny dark-coloured spots of excrement on walls or windows. Although they aren’t known to carry diseases which are harmful to humans, they can look unsightly and are difficult to clean

If cluster flies die in wall voids, they can attract larger bugs such as beetles

How to get rid of an infestation

Cluster flies can enter your home or property through even the smallest of cracks and openings. These tend to be around door and window frames or through other tiny unsealed gaps.

Spend some time doing a thorough search around your property so you can identify and fill any cracks and crevices in walls, window or door frames. Caulking works very well for this purpose.

If you know you’re prone to getting cluster flies, try to remember to keep windows and doors closed in the autumn because this is when they start looking for somewhere warm to hibernate.

You can also install insect screening or mosquito nets over air vents in soffits. It may also be useful to have netting on windows and doors if you like to let in the fresh air.

If you’re worried that you might have a cluster fly infestation, please feel free to get in touch and one of our experts will be happy to help.