Every summer, it happens. A hot, still day suddenly gives rise to thousands of winged insects, seemingly from nowhere. This is the annual spectacle often called 'Flying Ant Day.'
While the sight can be startling, it's a fascinating natural event. But what exactly are these creatures, and why do they all appear at once?
What is a flying ant?
A flying ant is not a separate species. They are the sexually mature queens and males from established ant colonies, including the common black garden ant, Lasius niger.
In entomology, these specific reproductive ants are known as alates. They spend most of their lives wingless within their home colony, but when the time is right, they develop wings to fulfill their sole purpose: creating new colonies.
A common black garden ant reproductive. Note its distinct "waist" and elbowed antennae.
Why and when do ants swarm? The 'nuptial flight'
This mass aerial gathering is called the nuptial flight. It is, essentially, a mating ritual hardwired into the ants' biology.
The trigger for this mass exodus is a very specific set of weather conditions. According to university researchers, including those at the University of California Division of Agriculture and Natural Resources, the flight typically occurs on a warm, humid day with low wind, often following a recent rain shower. These conditions not only aid flight but also make it easier for a new queen to excavate a nest in the softened soil.
By swarming in unison, alates from thousands of different colonies can meet and mate, which is crucial for ensuring genetic diversity. As the National Pest Management Association (NPMA) explains, the male's life ends shortly after mating. The newly fertilized queen then lands, sheds her wings, and attempts to find an ideal location to found an entirely new ant kingdom.
How to tell flying ants from termites
For any homeowner, this is the most critical identification skill, as termites can cause catastrophic damage to wooden structures. While they look similar in flight, the differences are clear upon closer inspection.
The core differences are found in the waist, antennae, and wing shape of the insects.
You can quickly identify them using these three points:
Waist:
Flying Ant: Has a very narrow, "pinched" or hourglass-shaped waist.
Termite: Has a broad, straight waist with no narrowing, giving it a tubular body shape.
Antennae:
Flying Ant: Has elbowed or bent antennae.
Termite: Has straight, often bead-like antennae.
Wings:
Flying Ant: Possesses two pairs of wings of unequal size (the front wings are significantly longer than the hind wings).
Termite: Possesses two pairs of wings that are roughly equal in length.
What should you do about flying ants?
The most important thing to remember is that common flying ants are harmless to people and property. They do not eat wood, and the nuptial flight phenomenon is typically over within 24 hours. Therefore, the best course of action is often patience.
If they find their way into your home, you can take these simple steps:
Close doors and windows: This is the most effective way to prevent them from entering during the peak of the swarm.
Use a vacuum cleaner: For any ants that have already made it inside, a vacuum is the quickest and cleanest method of removal.
Appreciate their ecological role: Before you get too frustrated, consider their benefits. As the National Wildlife Federation highlights, ants are vital to the ecosystem. During their flight, they become a massive food source for birds and other predators, and their nest-building aerates the soil.
In essence, 'Flying Ant Day' may be a temporary inconvenience, but it's also a powerful sign of a healthy, vibrant ecosystem in your own backyard.