Swirling swarms, virgin queens and carrier ants
A colony grows from the eggs laid by a mated queen. These hatch initially into workers, whose job is to forage and feed more larvae. As the colony matures in size, it prepares to reproduce itself by producing winged ants, both males and virgin queens.
The synchronised swarming of the nuptial flights brings together young virgin queens and males from miles away, thus refreshing the species’ genes. The swarms are also big enough to tilt the odds against any individual queen being eaten by a bird. The males are dead within hours, but the queens, often mating several times with different partners, spin back to earth and cut off their wings. They are ready to start a new colony.
Country and city ants
In Dublin’s city parks and under sun-warmed garden paths of the suburbs, the black ant is generally the common one, while in the countryside it is mostly the yellow meadow ant that rises from the fields. Back in the 1930s, the naturalist Robert Lloyd Praeger encountered their swarms as he walked into Blessington, Co Wicklow.
“They became more abundant on nearing the village,” he wrote (in A Populous Solitude, published in 1941), “ and I roughly estimated that on the last half-mile of road over a million-and-a-half of ants were crawling, while in the air above the road they were so abundant that my clothes were quite brown with them.
“The fields on each side were thick with them, the windows of the hotel were alive with them, and my tea was richly flavoured with them. Unless they were confined to a narrow line down which I had the fortune to walk, there must have been hundreds of millions of them within a mile of Blessington.”
Around the village today, such a density of colonies is found only in the last few vestiges of old and permanent grassland. Here, left undisturbed, yellow ants carry particles of soil to build their small, free-draining mounds, angled to the warmth of the sun.
Most Irish farmland is now a quilt of intensive silage fields, ploughed and reseeded with rye-grass and compacted by machinery – no landscape for the industry of Lasius flavus or its annual flights of sacrificial bliss.