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When to Expect the Swarm: Flying Ant Day 2025 in the UK


flying ants lasius niger black garden ant London 2024

Flying Ant Day, also known as "nuptial flight" often mistaken for a single occasion, marks a season of significant activity among Black Garden ants (Lasius niger) and Yellow Meadow ants (Lasius Flavus), specifically the emergence of winged queens and males for their nuptial flight, an event critical for colony propagation.

This event, usually occurring in the hot, humid months of July or August, provides fascinating glimpses into the captivating life cycle of these ants.

Urban heat islands often trigger these winged unique ants to emerge earlier in cities. The incident is a pivotal ecological point, supplying food for various animals and fostering biodiversity.


Why and When Does Flying Ant Day Occur?

Understanding the occurrence of Flying Ant Day requires a close look at several weather-related factors, all of which play a crucial role in signalling the ants that it's time for their nuptial flight. Here's a breakdown of the key triggers:

Weather Conditions:         

  • Temperature and wind speed are pivotal; ants prefer calm (wind speed less than 6-7 meters per second) and hot conditions (above 24 degrees Celsius).

  • Humidity is essential for keeping their wings and bodies moist during the flight.

Timing Variations Across Regions:

  • The phenomenon generally unfolds in July or August, but the exact timing can vary due to local weather conditions. For the last 24 years, 90 % of the nuptial flights occurred in July (see the table chart at the bottom).

  • Urban areas, like London, often witness these events earlier due to the Urban Heat Island effect, which results in warmer temperatures compared to rural areas.

Flying Ant Day Characteristics:

  • Not a single day but a period of increased activity, primarily observed in July.

  • The occurrence can extend over several weeks with multiple peaks, largely influenced by the weather, including periods of dry, warm, and not too windy conditions, always after summer rain.

These factors combined create the perfect conditions for the ants' nuptial flight, marking the beginning of what is popularly known as Flying Ant Day.


Understanding Flying Ant Day

To fully understand the phenomenon known as Flying Ant Day, it's essential to clarify some of the common misunderstandings associated with this natural event. Often, 'Flying Ant Day' is misleadingly interpreted as a single day of ant swarms, but it refers to several days spread across the summer season. This period is a significant stage in ants' life cycle, especially for the black garden ant, Lasius niger, and to a lesser degree, the red ants, Myrmica rubra. These specific days are marked by the appearance of young queen ants and males as they commence their mating flight—an important part of their reproductive cycle.

  • Species Involved: Primarily, the black garden ant (Lasius niger) and the yellow meadow ant (Lasius Flavus) represent nearly 90% of the participants in this event. However, red ants (Myrmica rubra) also partake, with the species observed depending on geographic location and prevailing weather conditions.

  • Nuptial Flight: The key event of Flying Ant Day is the mating flight, during which queens depart from their colonies to mate and form new ones. This occurrence doesn't limit itself to just one day; it can extend over numerous weeks. Catalysts for this event include warm weather, gentle breezes, and recent rain.

  • Misconceptions Addressed: The appearance of airborne ants, typically viewed as a nuisance, is a natural occurrence of great ecological importance. These ants, referred to as alates, are harmless and contribute significantly to our ecosystem. Their collective swarming behaviour not only aids in reproduction but also assists in the spreading and creation of new colonies across diverse environments.

Grasping these elements illuminates the complex dynamics of Flying Ant Day, underlining its importance beyond just a trivial seasonal nuisance.


Predictions for Flying Ant Day 2025

red ants UK myrmica rubra queen ant care

Looking ahead to Flying Ant Day 2025, it's crucial to recognise the volatile nature of the natural world. As we eagerly await this captivating natural spectacle, determining the precise date for Flying Ant Day 2025 continues to be a task filled with uncertainty. The constant changeability of climatic conditions and ecological elements adds to this ambiguity. Nonetheless, based on what we know about Flying Ant Day from 2000 to 2024 — anticipated to experience a prolonged 'bumper swarm' due to beneficial weather circumstances — we can form certain presumptions for 2025:

  • Weather Dependency: The occurrence and duration of Flying Ant Day heavily rely on specific weather conditions, such as temperature, humidity, and wind speed. Favorable conditions include warm temperatures, high humidity, and low wind speeds, which are conducive to the ants' nuptial flight.

  • Duration and Intensity: Based on the prediction of a prolonged swarm in the previous 24 years, we might anticipate a similar scenario in 2025 if weather conditions align. This could mean a series of swarming events spanning several weeks, rather than a single day of activity.

Understanding these factors helps us appreciate the complexity and beauty of Flying Ant Day, even if the exact date for 2024 remains elusive, however, we guess this year's flying dates will be between the 19th and 27th of July with a peak on the 24th and 25th of July (91% sure). Why we are 91% sure and not 100%? Well, we are talking about nature so nothing is certain but we have not been mistaken in the last 24 years.

Most queen alates in the UK, including Lasius Niger-Black ants and Flavus-Yellow meadow ants, are flying one month after the first 2-3 hot days. As enthusiasts and observers, our best approach is to stay informed and ready to embrace the spectacle whenever it unfolds, keeping an eye on weather trends as we approach the typical season of July and August.


Are you interested in starting an ant colony?

Setting up your ant colony requires a bit of preparation and understanding. Here are the key steps involved:

Finding a Queen Ant

Initiating an ant-keeping hobby commences with securing a reproductive queen ant. These sovereigns are typically spotted after their mating flights, which occur in the summertime. All you need to keep track of is 2-3 warm days in July followed by a day of light rainfall. Post the rainfall or on the succeeding day, you can anticipate a flurry of airborne ants. A queen who has discarded her wings is probably fertilised and prepared to establish a fresh colony.


Housing the Queen Ant

Queen Ant care in a test tube setup UK

Ensure that the queen ant is accommodated in a safe and shaded environment, with water readily available. A test tube setup is a popular choice for creating this habitat. The more compact the test tube setup, the more ideal it is. Get 4-5 test tubes (12x100mm) ready and be patient. Use clean (purified or mineral) water to fill up the water compartment along with organic cotton balls. Avoid using tap water at all costs as it's likely polluted and could destroy your queen ant's initial home and dash your hopes. To maintain a constant temperature and keep the queen in total darkness, wrap the test tube with aluminium foil. Position it in a quiet location, distant from regular household commotion and ensure the temperature ranges between 20 and 26 degrees Celsius. For the first month, refrain from disturbing the queen. After that, you can monitor her bi-weekly. Completely claustral species- those that do not require food during the preliminary nesting stage- can be left alone for a month while the queen produces her eggs and the inaugural generation of worker ants appear. All Lasius species fall under this category. Conversely, the Fire Queen Ant doesn't; hence, she must be fed weekly with a diet rich in carbohydrates and proteins. The first generation of worker ants are diminutive and are referred to as nanitics.

 Transitioning to a Larger Housing

As soon as the initial batch of labourers come into being and the ant colony starts expanding, a shift to more spacious accommodation, like a formicarium, becomes necessary. It's advisable to delay this move until the workforce population reaches a size of about 10-20 ants.


The Lifecycle of Flying Ants

Diving into the lifecycle of flying ants offers a fascinating glimpse into the natural world, revealing a complex and meticulously organized society. Here's a closer look:

Caste System and Roles:         

  • The queen ant is the heart of the colony, solely responsible for laying eggs.

  • Female workers are the backbone, caring for the queen, offspring, and the nest, besides foraging for ant food.

  • Winged males (drones) and virgin queens (princesses) are born for the sole purpose of reproduction, ensuring genetic diversity and colony expansion.

Reproductive Cycle:         

  • The nuptial flight is a pivotal event where new queens and males fly out, mate, and then the queens establish new colonies.

  • Males, having fulfilled their role, perish shortly after mating, usually immediately after the love act.

  • Mated queens shed their wings and scout for a suitable nesting site to begin their colony.

Ecological Impact:         

  • Beyond reproduction, this lifecycle plays a crucial role in ecosystems by controlling insect populations, serving as prey, and contributing to soil health.

  • Swarming provides protection and increases reproductive success, indicating a nearby well-established colony.

Understanding this lifecycle not only demystifies the phenomenon of flying ants but also highlights their importance in maintaining ecological balance.

  • Scientists say that if the bees disappear the ants will be the ones who can save our planet.


Impact of Weather Conditions

Delving into the complex interplay between meteorological conditions and the appearance of flying ants, it's intriguing to observe how these climatic elements greatly impact their behavioural rhythms. Here are some important observations:

  • Duration of Emergence: The period of activity for winged ants is not limited to a single day. Influenced significantly by the existing weather conditions, it can span more than 72 hours. This prolonged emergence period grants a wider timeframe for their mating flights, which are vital to the continuation and growth of their species.

  • Monitoring with Weather Radar: Impressively, the Met Office once spotted a congregation of flying ants, spanning more than a mile, using weather radar systems. This instance not only demonstrates the immense magnitude of these gatherings but also underscores the utility of weather radar for tracking insect demographics. These technological uses provide a crucial understanding of how human actions, such as light pollution, city expansion, and agricultural practices, affect insect populations.


These findings highlight the significant influence of climatic conditions on the lifespan and actions of flying ants, augmenting the need for ongoing scrutiny and study to comprehend their ecological functions and the possible consequences of shifts in the environment.


Impact on Ecosystems and Human Life

Flying ants, while often seen as a nuisance during their swarming events, play indispensable roles in our ecosystems and have intriguing interactions with human life. Here's a closer look at their impact:

Ecosystem Benefits:        

  • Soil Health: Their tunnelling activities aerate the soil, improving fertility and recycling nutrients.

  • Biodiversity Support: Serving as a crucial food source for birds and aiding in the survival of species like the silver-studded blue butterfly.

  • Pest Control: By preying on other insects, they help maintain a balance in the ecosystem.

Human Interaction:         

  • Nuisance vs. Harm: While swarms can be bothersome, flying ants are generally harmless to humans. Certain species may bite or sting if threatened, but the flying ants are queens (alates) and males (drones) only and do not sting or bite!

  • Indicators of Environmental Health: Large swarming events, though seen as an infestation, can indicate a well-established and healthy ecosystem nearby.

Conservation and Study:         

  • Citizen Science: Thousands have contributed to understanding flying ants, highlighting the importance of community engagement in conservation efforts.

  • Indicator Species: Their presence and behaviour can offer insights into the health of our environment, urging us to consider the impact of our actions on these crucial creatures and the broader ecosystem.

These results underscore the impact of weather patterns on the life expectancy and behaviours of flying ants, emphasizing the necessity for persistent observation and research to understand their role in the ecosystem and the potential repercussions of environmental changes.


Best Ants UK Flying Ant Day Archive 2000-2024

Year

Flying days London

2000

9-14 July (peaks on the 11th and 12th of July)

2001

7-13 July (peaks on the 9th, 11th and 12th of July)

2002

14-21 July (peaks on the 15th and 21st of July)

2003

21-29 July (peaks on the 23rd and 25th of July)

2004

6-11 July (peaks on the 7th and 10th of July)

2005

19-24 July (peaks on the 20th and 21st of July)

2006

15-22 July (peaks on the 16th and 19th of July)

2007

19-22 July (peaks on the 20th and 22nd of July)

2008

21-27 July (peaks on the 24th and 25th of July)

2009

4-9 July (peaks on the 4th, 6th and 8th of July)

2010

14-21 July (peaks on the 17th and 18 of July)

2011

27 July - 2 August (peaks on the 28th of July and 1st of August)

2012

24 July - 8 August (peaks on the 29th of July and 4th of August)

2013

27 July - 3 August (peaks on the 28th of July and 2nd of August)

2014

19-24 July (peaks on the 20th and 21st of July)

2015

29 July - 4 August (peaks on the 30th of July and 2nd of August)

2016

19-23 July (peaks on the 20th and 21st of July)

2017

5-13 July (peaks on the 7th and 12th of July)

2018

4-12 July (peaks on the 5th and 11th of July)

2019

21-27 July (peaks on the 23rd and 25th of July)

2020

12-19 July (peaks on the 12th and 117th of July)

2021

4-17 July (peaks on the 5th and 15th of July)

2022

10-16 July (peaks on the 11th and 15th of July)

2023

6 July - 8 August (peaks on 7th, 18th and 27th of July and 7th of August)

2024

12 July - 28 August (peaks on 12th, 17th and 28th of July)



Conclusion

In our examination of the 2025 Flying Ant Day and the life cycle of these flying insects, we've peeled back the layers to reveal more than just their mesmerising swarm behaviours. We've also shed light on their fundamental importance within ecosystems. The interaction between weather patterns, the essential mating flight, and the ecological contributions made by these unique ants underscore a captivating facet of our natural world. It goes beyond their periodic arrival, broadening our understanding of these insects and their crucial role in biodiversity as we look forward to their next appearance.

Recognising the event of Flying Ant Day serves as a nudge, reminding us of nature's fragile equilibrium and the necessity of preservation actions to uphold ecological well-being.


It invites us to watch, absorb and interact with our surroundings in significant ways. For the ones captivated by the complex realm of ants and keen to delve further into their study or scrutiny, purchasing live ants presents a straightforward route to bond with the wonders of nature. As we ponder over the knowledge collected, it's essential to preserve our inquisitiveness and reverence for these crucial insects and the wider ecosystem they support.


FAQs

When Do Flying Ants Typically Appear in the UK?

The phenomenon commonly referred to as "Flying Ant Day" usually takes place in July or August. This event, characterized by the mass emergence of winged ants, is influenced by hot and humid weather conditions. The exact timing varies across different regions of the country, largely depending on local weather.


Is There a Specific Season for Ant Activity in the UK?

Ants remain active throughout the year, but their presence is more noticeable during the warmer months as they venture out in search of food and water. Certain ant species, like carpenter ants, exhibit heightened activity levels during the spring and summer months.


Why Is There a High Concentration of Flying Ants in London?

The mass emergence of flying ants, particularly noticeable in places like London, is part of their mating process. After mating, male ants die, and the queen ants remove their wings to search for a suitable location to establish a new colony. This swarming behaviour serves a dual purpose: it provides a protective mechanism against predators, primarily birds, and increases the likelihood of successful mating. However, over the last 11 years, fewer numbers of winged ants have been swarming in Central London, this has been traced back to the air pollution and global warming effect, despite the Mayor of London Sadiq Khan's efforts and the Ultra Low Emission Zone (ULEZ).


Do Flying Ants Emerge Only Once a Year?

Contrary to the popular belief that flying ants make their appearance on a single day each year, findings from the Royal Society of Biology Flying Ant Survey reveal that the occurrence of flying ants is not limited to just one day. The frequency and timing of their emergence vary annually, heavily influenced by weather conditions.

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