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House Flies In Winter: Do Flies Hibernate in the Winter?

house flies in winter

What’s that buzzing around your kitchen? What is your dog chasing around the living room? What came in when you left the back door open too long? In many cases, the answer is the same: a fly.

Have you ever noticed that house flies seem to disappear during the winter months? How do they virtually vanish in the cold weather and reappear in full force once the weather starts warming up? Read on to find out.

What Flies Do During The Winter

Adult house flies in winter spend their days in cracks and crevices, away from humans. In the spring, these flies lay eggs on decaying materials. Although this behavior can be compared to hibernation, the truth is that flies do not spend the winter months in a deep sleep like some animals, including some species of turtles, snakes, bats, hummingbirds, ladybugs, skunks, and frogs. The cluster fly and other common fly species spend winter in diapause, a hibernation-like state of reduced metabolic activity.

Once temperatures climb in spring, the fly’s appetite and development return to normal. Unlike house flies, cluster flies prefer to lay eggs in the soil. Maggot hatchlings then seek an earthworm host. Once they find a host, they eat from one end of the worm to another and pupate in the victim’s shell.

Fly Life Cycle

How long do flies live? Flies have a relatively short lifespan, contrary to the popular belief that they live for a mere 24 hours. The truth is that flies can live up to a few months, but most live between two weeks and a month. The main goal of the species is to find a food source and breed. When winter is approaching, female flies seek a place to lay eggs that hatch into larvae. Flies prefer to stick with dirty areas such as fecal matter or garbage bins for egg laying. Flies are inactive at night, resting in beams, trees, shrubs, grass, outdoor wires, and near ceilings.

Each female fly can lay between 100 and 150 eggs at a time, and the reproduction cycle of a fly allows each female to apply a total of about 500 eggs in her short lifetime. These hatched larvae, commonly known as maggots, consume large amounts of food before protecting themselves for the winter in a type of cocoon. Once warmer weather arrives, the flies will emerge from these cocoons to find food and reproduce.

Large flies are known as cluster flies because of their tendency to band together to survive the winter through their parasitic relationship with worms. When comparing cluster flies vs. house flies, it’s good to note that the larvae live in the body of earthworms throughout the cold weather season. It is not uncommon for unseasonably warm weather to cause adult flies to emerge and seek shelter in a building when the cold returns, so some homeowners may have to deal with the unpleasant surprise of harboring flies in the wintertime.

Some other types of pests will seek a warm place to live during cold winter. Unfortunately, heated homes could be a target for insects, rodents, and other problems that are seeking winter shelter.

Do flies hibernate

The Risk Flies Pose To Humans

In addition to being a nuisance, flies can transmit disease. Flies pick up organisms while crawling and feeding on animal waste, garbage, and sewage, depositing it on people or the food they eat. Illnesses flies can spread include dysentery, diarrhea, typhoid, cholera, leprosy, and eye infections.

Several fly species bite humans. Most of us are familiar with horse flies, large and fast fliers that, as their name suggests, also prey on livestock. Deer flies can bite us and transmit disease while biting midges—more commonly known as “no see ‘ums” or gnats—can bite day or night near bodies of water. Black flies are expected in early summer and late spring and can leave painful, swollen bites behind.

Fly Control Measures

Given flies’ health risks, many homeowners want to take steps to avoid having these buzzing creatures inside. You can use fly swatters, automatic misters, sticky tapes or fly paper, baited traps, or electrocuting grids to deter or trap flies. Keeping garbage and pet waste in tightly sealed containers that are regularly emptied can help prevent flies from sticking around. Clean out waste containers of residue that could attract these pests. Some people find success filling glasses with water and a few pennies at the bottom or repelling them with essential oils.

ABC Can Handle Your Pest Problems

There’s a reason that some animals are called pests: they are an annoyance at best, and at worst, they can pose a health risk. Many pests are difficult for the average homeowner to handle without calling in the experts. Homeowners have counted on ABC’s exterminator pest control services for decades. Take advantage of a free inspection to determine how to handle your most persistent pest problems.

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  1. Mark 'Markus' Perro Commented ()

    Now I know what happens to them in winter

  2. Where do Mosquitoes go during Winter? | ABC Orlando's Blog Commented ()

    […] pest that seems to only hang around during the warmer months are the common house fly, find out more on where these pesky household pests disappear to during the […]

  3. Tamira Bennett Volk Commented ()


  4. ZexyZek Commented ()

    I was wondering about this.

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