September 20, 2025. Four and three nights ago we finally got some measurable rain. Two days ago, our Leaf-cutter Ants swarmed and danced in the early morning hours. As every time I spot this event, so probably once a year, the column of dancers rises and falls over a Thuja tree (Conifer like a cedar) in our drive way. One big old colony lives not far from it under an Ironwood. The dancers probably come together from several nests in the area. I know that I would find other dancing swarms simultaneously further down the road (this is a community with dirt roads, losely spaced houses, and mainly desert or not-at-all-landscaped yards.
These non-sting ants (Desert Leaf-cutting Ant (Acromyrmex versicolor)) live quietly in populous communities deep under ground with extensive fungus-growing chambers. Ever now and then they will venture out, cut leaves, carry them home and compost them under ground for their fungus gardens. (denuded bushes usually are not killed but rejuvenated. The larger Atta species in Central America can cause financial set backs for owners of teak plantations because the wood production is slowed down by the loss of leaves. But in a normal desert garden, the occasional raids of our small Acromyrmex are usually not more than a nuisance) When the weather is 'bad' too dry, too hot .... the ants close their entrances and stay hidden for months.
BTW, the characteristic cone shaped structures often seen are not nest entrances but heaps of sand that is expelled when new fungus chambers are built.
Of course, the entire dance party serves bringing nubile females and males together. The mature colony produces those about once every year and releases them all at once after a certain trigger, a good monsoon rain in this case. The sexes find each other up in the air, but then the 'bonded couples' or rather groups of one female with several males usually sink to the ground together .... This time I got the inpression that there were fewer females than normal .. annecdotal but possible in the current stress situation
