SPOTTED flying ants in your garden yet? Or maybe you've had to walk home through a swarm of them.

If you haven't already spotted them, the chances are you will do very soon as we edge closer to Flying Ant Day.

The what day?

Flying Ant Day is the day of the year when queen ants sprout wings and take off - and hundreds of male ants ALSO sprout wings to follow her and attempt to mate in mid-air.

When does it happen?

It usually happens at the end of July or the beginning of August and coincides with a period of hot and humid weather.

Winged ants appear at different times around the country and local weather conditions are critical for the coordination of swarming activity.

Ants tend to fly earlier in urban areas than rural areas, probably because temperatures are generally warmer in urban environments.

Is it really just one day?

According to the Natural History Museum, a multi-year citizen science project by the Royal Society of Biology found that the widely held idea of a 'Flying Ant Day' is actually a misconception: there is no single day when ants fly all at once.

Instead it should probably be named 'Flying Ant Season' as winged ants emerge over a few weeks with several peaks in appearances, each lasting only a few days.

The precise pattern of swarming varies from year to year and it's triggered by the weather.

There is also anecdotal evidence that Flying Ant Days often occur after some summer rain.

Where do flying ants come from?

Prior to swarming, ants are going about their everyday business and living in a colony in a nest.

Black garden ants nest in dry soil.

You'll often find them in flower beds and lawns, and under paving slabs or stones.

In the few weeks before the swarming event happens, you may see heaps of soil appearing above the nests.

Why do ants fly?

An ant colony can only expand so much. At some point a new queen will need to strike out on her own to begin a new colony.

She needs to meet and mate with a male from a different colony and find a new area in which to start building her nest. Growing wings and flying enables her to do this.

The large winged females and the smaller winged males are often seen flying joined together. This is known as the nuptial flight.

Why do ants swarm?

This protects them from predators and increases the chance of reproduction - with larger numbers of their species around the ants won't have far to look for a mate.

What happens after the nuptial flight?

Once ants have mated, the role of the males is over.

The mated queens quickly chew off their own wings and begin looking for a suitable site in which to nest and set up a new colony.

This is why you often see large ants walking around after a 'Flying Ant Day' and may even see discarded wings scattered over pavements.

After the nuptial flight, the male ants usually only live for another day or two. Their sole reason for existence is to mate with new queens.

I hate flying ants, can't I just kill them all?

They might be annoying but their tunnelling activities play a vital role in improving soil quality.

Their swarming events also provide a vital food resource for many species of birds including swifts and gulls.