Each year, as summer heats up, many of us experience a peculiar natural event: the sudden appearance of swarms of winged ants. One moment, your garden or local park seems normal, and the next, the ground is alive with crawling insects, and the air buzzes with their frantic flight. This phenomenon often leads to the question: Are There Flying Ants, and if so, why do they suddenly appear?
Let’s delve into the world of these winged insects, commonly known as flying ants, to understand what they are, when they emerge, and why they play a vital role in our ecosystem.
What Exactly Are Flying Ants?
The term “flying ants” refers to ant alates. Alates are sexually mature ants, both queens and males, that possess wings. In the UK, particularly in urban environments, the flying ants you encounter are almost invariably the queens and males of the black garden ant, scientifically known as Lasius niger. The larger of these winged insects are the queen ants, noticeably bigger than worker ants and capable of reaching up to 15mm in length.
Black garden ant queen and workersLasius niger) alongside smaller worker ants. The queen is significantly larger and possesses wings for her nuptial flight.
When Does Flying Ant Season Occur?
The annual emergence of flying ants typically happens during July and August, perfectly timed with periods of warm and humid weather. It’s important to note that flying ant appearances can vary across the country, heavily influenced by local weather conditions which play a critical role in synchronizing their swarming activity.
Interestingly, flying ants often appear earlier in urban areas compared to rural settings. This is largely attributed to the urban heat island effect, where urban environments tend to retain more warmth than surrounding rural areas, thus prompting earlier flights.
Winged ants preparing for flight on pavement
The disruption caused by flying ants is sometimes so significant it even makes headlines, occasionally affecting major events like Wimbledon. While swarms can emerge anytime from June to early September, it’s crucial to understand that the idea of a single “flying ant day” is actually a misconception.
Extensive research, including a multi-year citizen science project by the Royal Society of Biology, has shown that there isn’t one specific day when all ants fly simultaneously. Instead, we experience a ‘flying ant season’. Winged ants emerge over several weeks, with multiple peaks in activity, each lasting just a few days. The exact pattern of these swarming peaks varies from year to year depending on weather patterns.
Weather is indeed the key trigger for swarming. Studies have found that ants are most likely to fly on days that are warm, calm (not windy), and when conditions are an improvement from the preceding day. Anecdotal evidence also suggests that flying ant swarms often occur following summer rain.
Where Do Flying Ants Originate?
Before they take to the skies, flying ants live in established colonies, typically nesting underground. Black garden ants prefer dry soil for their nests, commonly found in locations such as flower beds, lawns, and beneath paving slabs or stones. Patios are particularly favored nesting sites. They thrive in almost any dry, open area warmed by the sun, including gardens, pavements, brownfield land, heathland, grassland, and even coastal regions.
In the weeks leading up to the swarming event, you might notice small heaps of soil appearing near ant nests, a sign of the colony preparing for the emergence of alates.
Exposed ant nest with pupae and worker antsLasius niger ant nest revealing worker ants and pupae, showcasing the hidden world beneath our feet.
Ant colonies operate under a caste system, with each ant having a specific role. The queen’s primary function is to lay eggs, while female worker ants care for the queen, eggs, and larvae. Workers also undertake foraging for food, expanding the nest, and maintaining the smooth operation of the colony. The majority of eggs develop into workers, but when a colony reaches maturity, the queen begins to produce virgin queens and males – the alates.
When these winged males (drones) and virgin queens (princesses) emerge from the nest, they disperse widely. This scattering is a strategy to maximize mating opportunities with ants from different colonies, thereby reducing the risks of inbreeding.
The Purpose of the Nuptial Flight
Ant colonies have limitations to their size and expansion. For a colony to propagate and spread, new queens must establish their own colonies. To achieve this, a virgin queen needs to mate with a male from a different colony and then find a suitable location to begin her own nest. Developing wings and taking flight is the mechanism nature provides for this essential dispersal and mating process.
Each year, alates emerge from their nests for this purpose. They are not interested in human activities or picnics; their sole focus is finding a mate for reproduction. Often, you can observe the larger winged females and smaller winged males flying in tandem – this event is known as the nuptial flight.
Mass of winged ants on the ground
Why Do Ants Swarm in Such Large Numbers?
The sheer volume of flying ants appearing at once might seem overwhelming, but there are crucial reasons for this mass emergence. One primary reason is predator protection. There is safety in numbers, and swarming provides a dilution effect against predation.
Another critical reason for swarming is to maximize reproductive success. By having a large number of individuals in the air simultaneously, ants greatly increase their chances of finding a mate.
During this brief, once-in-a-lifetime mating period in the air, a queen typically mates with multiple males, ensuring a sufficient supply of sperm for the rest of her reproductive life.
Life After the Nuptial Flight
Once mating is complete, the males’ role ends. The mated queens quickly shed their wings by chewing them off and begin searching for a suitable nesting site to establish a new colony. This explains why you often see larger, wingless ants walking around after a flying ant swarm, and you might also notice discarded wings scattered on pavements.
Wingless queen ant after matingLasius niger queen ant that has removed her wings after successfully mating, ready to start a new colony.
The ants we typically see throughout the rest of the year are female worker ants, tirelessly foraging and maintaining the colony. After finding a suitable location, the newly mated queen digs an underground chamber and lays her first eggs, which she nurtures to adulthood. Remarkably, she will not eat for weeks, sustaining herself until her first generation of daughter worker ants are ready to forage and provide food for her and the growing colony.
The sperm the queen received during her nuptial flight will last her entire life, enabling her to lay fertilized eggs and reproduce for many years. Queen ants are prolific, and colonies can grow to be incredibly large, sometimes housing over 20,000 worker ants in mature nests.
Lifespan of Flying Ants
Male flying ants have a short existence. Their only purpose is reproduction, and they are produced by the colony solely during the flying ant season. Developing from unfertilized eggs, male ants typically live for only a day or two after the nuptial flight, with a total lifespan of about a week.
In contrast, queen ants of Lasius niger can live for up to 15 years in general conditions, and even longer in captivity, with records showing up to 28 years. However, their winged, flying phase is a very brief part of their long lives, occurring only when they are young queens setting out to establish new colonies.
The Unexpected Benefits of Flying Ants
While often seen as a nuisance, flying ants actually play beneficial roles in our ecosystem. Their tunneling activities are vital for improving soil quality through aeration and nutrient distribution.
Furthermore, flying ant swarms are a significant food source for numerous bird species. Swifts and gulls, among others, can often be observed feeding intensely on these swarming insects.
Seagulls feeding on flying ants
Black garden ants and the related cornfield ant (Lasius alienus) are also crucial for the survival of the silver-studded blue butterfly (Plebejus argus), a butterfly species that has faced population declines. These ants and butterflies have a mutually beneficial relationship. The ants protect the butterfly caterpillars from predators, and in return, they feed on sugary secretions produced by the caterpillars.
Ants tending to a Plebejus argus caterpillar
- Lasius ants protect the caterpillars of the silver-studded blue butterfly (Plebejus argus) in exchange for nutritious secretions, a remarkable example of mutualism in nature.*
Ant Diversity in the UK: Beyond Black Garden Ants
Ants, along with bees and wasps, belong to the Hymenoptera insect group, easily recognized by their three distinct body segments. The UK is home to around 60 ant species, all living in complex social colonies.
While black garden ants are the most commonly observed flying ants, other species also participate in nuptial flights. Red ants (Myrmica rubra) are another common UK species that produce winged alates and swarm. However, surveys indicate that black garden ants account for the vast majority of observed flying ants, nearly 90% in Royal Society of Biology surveys.
Winged red ant Myrmica rubraMyrmica rubra ant, a common red ant species in Britain that also undertakes nuptial flights.
The type of flying ant you might see depends on your location. For example, woodland areas may host wood ants. Crucially, all ant species require favorable weather conditions – no rain or wind – to fly. The specific temperature and humidity thresholds that trigger swarming and flight vary among species, leading to different timings for their nuptial flights throughout the flying ant season.
In conclusion, flying ants are a natural and essential part of our summer ecology. While they might be a temporary nuisance, understanding their role in reproduction, soil health, and the food chain reveals their importance in the bigger picture. The next time you see a swarm of flying ants, remember you are witnessing a remarkable natural phenomenon, crucial for the continuation of ant colonies and the broader ecosystem they support.
