Cluster Flies or Black Flies in House? List of Steps to Take

If you go on Google and search common pests, you would likely find cluster flies in the list. If you have black flies in house, you probably want to rid of cluster flies or kill them quickly.

What are Cluster Flies?

Cluster flies, also known as attic flies, are a type of fly that is often found near homes. They can be mistaken for the common house fly. They are completely drawn to the warmth of buildings and enter through cracks and crevices in the cold winter months.

As the days grow shorter and temperatures start to drop, these cluster flies begin to enter buildings in high numbers in search of overwintering sites.

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However, once the weather starts to warm up, the warmth of the sun will wake them up, and the flies start to become more active after coming out of their cold temperature dormancy.

As the warmer months approach, you’d have these flies crawling through electrical outlets, window pulley holes and other small openings around windows, door frames, moldings and baseboards.

Their random crawling movements can be a nuisance to homeowners. The large, black flies that show up in bedrooms and on window sills from late fall through early spring are common household bugs.

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Should You Worry About This Insect?

These insects do not reproduce indoors, therefore homeowners don’t have to be concerned that the insects are hatching from dead animals or other disgusting things within the home’s attic or wall.

Of course, you’d always benefit from a thorough inspection of your home to know if you have to rid of cluster flies.

Cluster flies develop as parasites inside the earthworms. There are three generations of flies produced each summer, with the final generation migrating to houses and other buildings during late August and early September.

This last generation is responsible for the majority of fly activity seen indoors during the fall and winter months. They will send winter in a protected location, and then start the cycle all over again.

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Do They Look Like the Common House Flies?

Cluster flies are not harmful to humans, but their presence can be a nuisance. These bugs are often seen in large groups, or “clusters,” which is where they get their name. Of course, your fly swatter can be very useful against them as well.

The common cluster fly is large and black, and can easily be mistaken for the common house fly. However, they are a bit larger than the housefly.

The main difference is the yellowish-golden hairs on the thorax, and a prominent dark-and-light coloured chequered pattern on the abdomen of a cluster fly.

Cluster flies are not known to transmit any diseases. However, their larvae can pose a danger to pets, as they have been known to infest bird nests. A cluster fly typically becomes active in summer and early fall, and they can be a nuisance until they die off in the winter.

It does not breed indoors, so once they are removed from a building, they will not return.

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Life Cycle of Black Cluster Flies or Attic Flies

Cluster flies are often mistaken for house flies, but they are actually a different species altogether.

“Why Are These Large, Black, Slow-moving Flies in My Home?”

Cluster flies are medium-sized insects that are most active in the late summer and early autumn. They get their name from their tendency to congregate in large numbers, often inside homes and other buildings.

While cluster flies are not known to transmit or carry disease, they can be a nuisance to people trying to enjoy the outdoors. They have a completely different life cycle than other types of bugs. They are common inside houses in fall and winter.

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The life cycle of these bugs begin when the adults lay their eggs in manure or other decaying organic matter. The cluster fly eggs hatch into larvae, which then climb up onto grasses or other plants.

In the fall, the larvae drop to the ground and burrow into the soil to overwinter. In the spring, the larvae pupate and emerge as adults. These slow moving flies then begin the cycle anew by laying more eggs.

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Pest Control: Cluster Flies Lay Eggs

During the winter, big black flies are drawn to indoor locations.

They are especially attracted to hibernating in attic spaces and the cracks between your walls and doors during the cold months. This is why your walls might need treatment as well.

They can also lay clusters of eggs in these places, which will hatch when the weather warms up. If these fly species lay eggs eggs in your house during the winter, your heater can generate enough heat to simulate summer conditions, causing the eggs to hatch.

Unlike the typical housefly, these adult flies do not feed or lay eggs on a dead animal.

Cluster flies are mostly concerned with laying eggs and breeding maggots outdoors during warm months. Their maggots primarily target and feed on earthworms in underground areas.

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When Do You Find Black Flies?

Cluster flies enter homes in the fall and winter. They are larger than common house flies. These bugs are not a health hazard, but they can be a nuisance just like your house flies.

Cluster flies are attracted to light and often fly around windows and doors in homes. Although they congregate in large numbers, they do not bite or sting, and they do not transmit diseases.

Be sure to have a treatment plan for when your home is plagued with a cluster fly, so you would know how to get rid of cluster flies or any other insects quickly.

How to Kill or Get Rid of Cluster Flies

Black Flies in House Pest Control

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Before you get rid of cluster flies, make sure that they’re indeed black or cluster flies. These slow moving flies target people and livestock. They’re biting critters, known to pay unwanted visits to homes with water bodies located nearby.

The average size of an adult black fly ranges between 5 to 15 mm. Their bodies are quite bulky compared to other types of house flies, featuring large wings, compound eyes, and a humped-looking thoracic area.

While it’s true that these cluster flies can get inside houses, they’ll mainly just annoy you. Black flies’ bites rarely transmit diseases, but you still probably want to prevent cluster flies infestation in your home.

Keep Away from a Cluster Fly Home

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One of the ways cluster flies may find their way into your house is actually through you! No, a cluster fly won’t hide inside your body and come out later.

Cluster flies like to stay around waterways (ponds, streams, lakes) as well as places with lots of vegetation and high moisture. If you’re planning to visit such areas, try to postpone your trips outside the summer months because that’s when you’ll find that this pest is most active.

By avoiding encountering cluster flies outdoors, you’re less likely to see them indoors – migrating into your home’s walls.

Prevent Flies or Get Rid of These Pests

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 Dish Soap, Sugar, and Vinegar

  • In a bowl or a dish, pour some vinegar (apple cider is our recommendation but you can try other types as well) and add one tablespoon of sugar.
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  • Dissolve the sugar into the vinegar, then add a few drops of dish soap – preferably with a fruity scent.

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  • Leave the concoction out in the open uncovered. You can also use plastic wrap to cover the dish, but make sure to poke some holes in it so that flies are attracted by the smell.
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Wrap Up: Control the Infestation

Getting rid of cluster flies is all about methods to repel these cluster flies. You can also ask for the help of professional pest control company, and you would likely find a local branch of a good company near you.

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