Nature Notebook – Midge Swarm

Before the colder temperatures arrived, we were treated to another of nature’s autumn shows. A midge swarm formed at an edge of our front pond where the tiny gnat relatives fluttered up and down in a vertical column. A different generation performed for us in the spring. Although the weather was a bit cool, the insects could stay warm because of the heat generated from their rapid wing-beats.

Most of the dancers were males waiting for a female to pass through the cloud. After she was fertilized, the female dropped to the pond to lay eggs in the water.

The tiny larvae that will emerge in a few days will overwinter in the mud of the pond. They will feed on plankton, algae and decaying matter. A spring breeding swarm will then form as new adults finish pupation.

Recent observations suggest that some adult midges may feed on the sugars produced by non-floral nectaries. However, it seems most do not feed at all. So, the midge life cycle, and swarm, is short-lived.