Of all the exciting phenomena of the insect world, one that holds a special fascination for me is seeing swarms of dragonflies on a muggy, late summer evening. Dragonflies, of course, are those long, slender-bodied, familiar insects commonly seen skimming over the water of a lake, stream or pond, their brightly-colored body and transparent, cellophane wings shimmering in the sunlight.
There is another time dragonflies are noticed: that's in the evening when they are on a "feeding frenzy" just before dusk. Dragonflies are aggressive predators. As they fly back and forth over the water or dart in a zig-zag fashion above your lawn they are literally sweeping mosquitoes, gnats, winged ants and other small insects from the air using their spiny front legs that are held like a basket just under the mouth. In the fall and at dusk, the insects they are probably eating the most of are winged ants.
Winged ants, also called swarmers, are emissaries produced by a successful, well-established colony that has reached a stage where there are resources to spare. These special adults are different from the usual wingless worker ants. Swarmers are the sexually developed, winged males and females that depart from the colony in an attempt to perpetuate the species by establishing a new colony somewhere else. They have very, very slim chances of success. Most will die of starvation, dehydration or will be eaten by birds, dragonflies or other predators. Though almost all will fail, just enough succeed to spread the species and ensure its survival. Winged ants are harmless. They do not create mounds in your lawn, dirt piles on your driveway or sawdust at the base of your hollow tree. Swarming is a temporary, natural event and is not a permanent or major problem. Besides, as mentioned, swarmers are beneficial as an important link in the ecosystem food chain. Outdoors, ignore them if possible.
As for the dragonflies, they do not harm people, pets, crops, landscape plants or houses. They are entirely beneficial, first as a vital part of the aquatic food chain, and second as predators of mosquitoes and other pests. Live and let live. Sit back and enjoy the show.
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