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When is flying ant day 2026 with peak due in days, as entomologist explains phenomena
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When is flying ant day 2026 with peak due in days, as entomologist explains phenomena Ant specialists say this year's even will be likely be 'more intense' than before Every year the skies fill with thousands of black ants in what has been named "flying ant day". However far from a single day, the winged creatures are likely to be around for a few days or longer as they try to find mates and set up new colonies.
When is flying ant day 2026 with peak due in days, as entomologist explains phenomena
Ant specialists say this year's even will be likely be 'more intense' than before
Every year the skies fill with thousands of black ants in what has been named "flying ant day". However far from a single day, the winged creatures are likely to be around for a few days or longer as they try to find mates and set up new colonies.
The Royal Society of Biology (RSB) explained: "Flying ants often seem to appear on the same day in different locations in the UK – flying ant day. Most ant colonies start with a flying ant — when young queens leave the nest to found their own colony. However, our citizen science project, the Flying Ant Survey, found that there is not actually one day where these ants all appear all at once, but that, depending on weather conditions, the ants can start emerging and flying at almost any point during the summer months, and won't all necessarily appear only on one day either."
What causes 'flying and day'
The RSB said flying ant day is when when males and new queens leave the nest to mate, with many ant colonies doing so on the same day when the conditions are just right. This includes the black garden ant Lasius niger and is the way many leave their previous nest to begin new colonies.
Its survey found that there is often not just one flying ant day but on as many as 96% of days between the start of June and the start of September flying ants are spotted. For the actual date - this depends on a number of factors.
The RSB said: "Weather turns out to be an absolutely critical factor in triggering ants to fly. By comparing records of flying ants with the nearest weather station data, we were able to untangle some of the factors that trigger ants to take to the sky.
"Ants only flew when the temperature was above 13C and when the wind speed was less than 6.3m per second but overall ants like it calm and warm. During the course of the study, every day in the UK summer that had a mean temperature above 25C had ants flying somewhere."
Speaking on a video on the RSB site, entomologist Professor Adam Hart, of the University of Gloucester, confirmed there was not one "flying ant day". He added: "Sometimes you could have ants flying in your garden weeks after each other."
He explained as the phenomenon was linked to "weather, hot days above 25 degrees, low wind, and rain perhaps in the next few days" it also meant you "don't get this massive coordination across the country". He added: "So, in a good summer, you can actually have lots of flying ant days throughout that period."
What are flying ants?
Prof Hart explained that flying ants are the reproductive ants. He said: "Most of the ants you see walking around the pavement are workers, and they're never going to start a new colony. But the flying ants are the males and the potential new queens that emerge to mate.
"So flying ants are basically a big mating day for those ants coming out of the ground, mating up in the air, the females will land back down, the males too. But we tend to forget about them.
"The females are what it's all about, and they'll dig a little hole and they'll start to try and create a new colony if they manage to avoid all the gulls and other things trying to make them lunch."
He said flying ants did not swarm as honeybees do, so they did not form a collective mass, but they were "everywhere in large numbers". He added: "That can be quite annoying. But at the end of the day, they're completely harmless.
"They're actually very good bird food. They're excellent, excellent for that. But also, ants are incredibly important for aerating the soil and nutrient recycling and all sorts of other ecological functions.
"So although they can be quite annoying, they're more than harmless. Actually, they are completely beneficial for the environment. So the best thing to do is just to enjoy one of nature's spectacles. It won't last forever. It's typically late afternoon for a couple of hours, and then and then they'll be gone, perhaps for a few weeks, or perhaps even if the weather's not so good for the whole year."
How ants mate at this time
The RSB said: "Ant colonies start with a female flying ant that will have left their previous colony to begin a new one. Unlike the female worker ants we see throughout the year, the queen starts her adult life with wings, and is noticeably larger.
"Both males and females take to the skies, travelling away from their nest in a bid to find mates from other colonies, and settle down in suitable conditions to begin their own colony. When far enough away, the females and males commence breeding, with mating taking place during flight and the male dying shortly after.
"The fertilised female then lands, chews off her wings, goes about creating a new colony or finding an existing one, and starts to produce offspring.
When is flying ant day 2026
So while there is no single "flying ant day" there is a window when people are more likely to see them. While the RSP does not predict when the phenomenon will appear a number of other experts have shared their views online about when it will happen in 2026 - and it is likely to be within days.
According to Country Living it will be between July 20 and 25. Best Ants UK, however predicted it would be between July 24 and 29 and explained why.
It said the first flight was earlier this year following a heatwave in the last week of May which primed colonies. However it said this would only involve 11-17% of the ants.
It added: "It is an early advance flight triggered by back-to-back heat waves — the late-May spike followed by this second, more intense surge. The remaining 83–89% of queens will hold back for the main peak between 24 and 29 July, with a smaller second swarm expected around 2 August."