The first heavy rain after a dry spell brings a swarm of small flying insects to lit windows across the country, and every year it produces the same question. Are those flying ants, which are a nuisance for an evening, or are they termite alates, which mean a colony is established somewhere near your house?
You can tell them apart in a few seconds, and it is worth learning because the two outcomes are very different.
Look at the waist first. An ant has a narrow, pinched waist between its thorax and abdomen — an obvious hourglass. A termite has no waist at all; its body is a broad, even tube from front to back. This is the single most reliable difference and you can see it without magnification if the insect is still.
Then look at the wings. A termite has four wings of equal length, all noticeably longer than its body, and they detach very easily — which is why you usually find a scatter of discarded wings on a sill or in a cobweb rather than the insects themselves. An ant has four wings too, but the front pair is clearly longer than the back pair, and they stay attached.
Finally, look at the antennae. Ant antennae are elbowed, with a distinct bend partway along. Termite antennae are straight and slightly beaded, like a tiny string of pearls.
If it is termites, what it means is this: a mature colony somewhere nearby has produced reproductives and sent them out to start new colonies. Swarming is a sign of an established colony, not a new one. That colony may be in your garden, in a neighbouring property, or in your building. Alates themselves do no damage and most of them die within hours, so there is nothing to spray.
What matters is what you do next. Check for mud tubes running up foundations, exterior walls or piers — pencil-width earth tunnels are how subterranean termites travel. Tap door frames, skirting and any structural timber and listen for a hollow sound. Look for paint that appears blistered over a flat area, and for door or window frames that have become stiff.
Collect a few of the discarded wings in a jar as well. If you do call someone out, having them saves guesswork about the species.
If you find any of those signs, request a quote and send photographs of what you have found. Termite work is priced from the construction and the extent of the damage, so the more you can show, the closer the quote will be. If you find nothing, note the date of the swarm anyway — swarming near your property is worth remembering next year.
And if the waist was pinched and the antennae were elbowed, it was ants. Close the window, turn off the outside light for the evening, and enjoy the rain.