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Where Do Flies Go at Night?

All living creatures need sleep, and flies are no exception.

While most of us may never have seen a fly ‘sleeping,’ they do, in fact, need sleep just like us.

And their hunt for a safe and comfortable sleeping spot begins soon after sunset.

So where do flies go at night?

Like us, flies are usually asleep during the night. Also, like us, flies will take naps during the day.

What’s more, flies will sleep anywhere they can instead of finding a place that does not have predators.

You might see a fly sleeping anywhere in your home – on the wall, ground, countertop, leaves of plants, or anywhere else.

They don’t care where they sleep.

While flies do generally sleep at night, they may flutter around in the dark and find unique ways of getting through the night during the winter.

Do flies sleep?

The simple answer is yes; flies do sleep at night. They will find themselves a cozy spot once it starts getting cooler and take a rest.

Flies sleep deeply as well as lightly, just like humans.

Flies need sleep when they use up a lot of energy. While many would think this energy is primarily necessary for flying around, this is not true.

Flies also use up a lot of energy in brain activity.

When the learning pathway is activated in the fly’s brains during the day, their need for sleep becomes much more significant.

They will most likely sleep deeper than average.

However, despite deep sleep, they will wake up if they sense predators approaching.

Surprisingly, flies don’t just sleep at night; they also take naps daily! They will do this in shady places to escape the afternoon heat.

If they stay out in the sun for too long, they will get thirsty, overheat, and die.

They will often not search for a predator-free place and will sleep wherever they are. This could be on leaves, walls, or even on the floor.

However, they also have an excellent grip to keep them from falling while sleeping.

In fact, fly sleep is much more like human sleep than we’d think. Their sleep cycle is just as affected by the food they consume as ours.

For example, if they consume caffeine or cocaine, they will stay awake, and antihistamines and alcohol will tire them.

Flies usually tend to sleep more in warmer temperatures than in cooler ones.

If they cannot fulfill their required sleep at night, they will sleep more the next day to make up for it. This is what scientists call sleep rebound.

Sleep deprivation also affects flies just like it affects us and can be detrimental to their memory.

Research also found that baby flies usually need more sleep than adult flies since it is necessary for their brain development.

When do flies go to sleep?

Like humans, when the sun goes down, it’s time for flies to sleep.

They will find a safe place to rest and spend the night there.

The fly brain is very active during the day as they try to learn and remember things.

This learning and remembering requires a lot of energy, so they need to sleep at night to restore that energy.

How long do flies sleep?

Flies generally sleep for about 8 hours each night. However, they may take naps during the day as well.

Their sleep cycle is similar to ours in that they have a night of light sleep and a deep sleep.

The light sleep doesn’t last as long as the deep sleep, but it allows them to be alert in case of predators.

During the winter, flies may not sleep as much since there isn’t as much for them to do.

They may flutter around in the dark or find other ways to get through the night.

What happens if flies don’t sleep?

If flies don’t sleep, they can suffer serious consequences.

For example, sleep deprivation can lead to memory problems and decreased brain activity.

It can also affect their ability to fly and land properly.

In fact, research has shown that sleep deprivation in flies leads to a decrease in lifespan.

So, it’s pretty clear that sleep is essential for flies!

Do flies fly in the dark?

From house flies to flesh flies, most flies are active in the daytime and become inactive during the night.

This is because they need polarized light to be able to see, and the lower temperatures at night will cause them to become slow and sluggish.

As darkness falls, many flies take refuge under leaves or on tree trunks, where they will rest until the sun comes up again.

Flies don’t have a nest or colony and will sleep wherever they find a place.

Most flies follow this pattern, but some exceptions, like sand flies and fruit flies, prefer cooler temperatures and will be more active during dawn and dusk.

What do flies do at night?

So, we know that flies sleep at night just like we do.

But what else do they do?

During the winter months, when it’s too cold to fly, many species of flies will enter into a state of dormancy called diapause.

They will not eat or drink in this state, and their metabolism will slow down significantly.

They will remain in this state until the weather warms up again and they can become active once more.

This leads to my next point.

Where do flies go in the winter?

Flies are unable to handle cold temperatures.

The slow laziness makes them unable to look for their own food, making them vulnerable to predators.


When the weather gets too cold, most flies will migrate to warmer regions, where they are more likely to find food and be able to survive.

In fact, most flying insects choose to migrate during the colder months.

This is because they are cold-blooded, and their metabolism slows down in the colder temperatures, making it hard for them to find food.

So, they will fly to a warmer region where they can be more active and better survive.


Another option for flies is to enter into a state of hibernation.

In this state, they will again slow down their metabolism and enter into a state of dormancy.

However, they will not migrate to a warmer region.

Instead, they will find a safe place to stay until the weather warms up again.

This could be in the form of a dark, warm cave or even under a rock.

As long as they are in a place where they won’t be disturbed, and the temperature is stable, they can hibernate until it’s time to come out again.


Overwinter means to survive the entire winter season in a specific form.

For example, some animals will grow a thick coat of fur to help them survive the winter.

Some plants will die back and regrow in the spring.

As for flies, they enter into a state of diapause where their metabolism slows down significantly. They can remain dormant until the weather warms up again.

As Larvae

Sometimes, flies will spend the entire winter in the larvae stage, and they will hide behind a layer of leaves and survive the cold.

In fact, in some cases, they replace all the water in their body with glycerol, which is a form of antifreeze to protect themselves.

In other cases, larvae dig into the soil and stay warm.

Sometimes, suppose larvae have hatched in fecal matter. In that case, the heat byproduct of the decaying process will keep the larvae warm and alive.

As Nymphs

One option for species of flies with nymphs is to spend the entire winter season under the ice in water bodies.

There, they can grow and feed until the warm weather returns, and they can emerge as fully grown flies.

As Eggs

Some flies will lay their eggs close to the winter, remaining unhatched until the cold weather is gone.

However, in some cases, the eggs will hatch in the winter, and the larvae will stay hidden until they come out and feed.

As Pupae

Some flies will remain in their cocoon during the pupa stage until the winter passes.

These can often be found attached to branches of plants that produce food.

The pupae will stay there until the warmer weather returns, and they can hatch into fully grown flies.


Diapause is a condition where the metabolism of a living being slows down drastically.

Flies use this to survive the cold winter months – their metabolic activity is reduced until it is only enough to keep them alive and nothing else.

Their activity, growth, and development are halted and don’t resume until the cold passes. It is similar to hibernation but does not involve any sleep.

In some cases, where the cold is very severe and the flies have grown to adulthood, they may simply die of the cold.

You may find flies in your home during the wintertime if you live in a place with many people.

Naturally, this is because the flies are looking for a warm place to stay in.

Flies can be a nuisance, but they can also carry diseases. It is best to get rid of them as soon as possible.

How to get rid of flies at night

The best way to do this is to figure out where they are coming from and block the entry points.

You can also use fly traps and other devices to help you get rid of them.

How long do flies live?

While the irritation lasts forever, the flies themselves don’t.

In fact, adult flies can live for only about 15-30 days if predators don’t eat them. While that is long enough to be annoying, it’s a miserably short lifespan.

And yet, they don’t seem to reduce in population! The answer to that is that they have a very high reproduction rate.

There are three main things during a fly’s life: food, breeding, and death.

On average, female flies will lay up to 75-150 eggs at one time, and during her entire lifetime, about 500 eggs.

That means that every female fly you see could have about 500 flies behind her – which is why you never know the number of flies goes down.

Flies will usually look for disgusting areas to lay their eggs, such as garbage bins, fecal matter, and sometimes in the soil or leaves.

The next stage is larvae – this is where they are hungriest. Nymphs look like worms, and their characteristics usually depend on fly species.

After this, they will develop into pupas, and the fly becomes dormant. It forms a cocoon around itself and doesn’t feed or move.

Most of the changes occur during the pupal stage. This is where the fly develops into the adult flies we are so familiar with.

These three stages can take up to 10 days of a fly’s life, and it will search for food, breed, and eventually die.

Related Questions

Where do flies nest?

Flies do not build nests. They do not live in colonies and are solitary creatures who will look only for their own sustenance. When they have to sleep, they will do so on any available surface.

Do flies bite?

The most common fly species is the housefly, and because it has sponging mouthparts, it is physically unable to bite. However, other species of flies may bite, and while the occurrence is not a common one, they may do so to suck your blood, which provides them with nutrients.

Do flies do anything useful?

Flies are incredibly annoying creatures to us humans, but they have their own role in the ecosystem. They are natural decomposers and help break down organic matter, which will release essential nutrients into the soil for plants and bacteria to use. Flies are also crucial in the pollination of flowers. In fact, the only known pollinators for the cacao bean, which is used to make chocolate, are flies.