Most of us lately have been seeing many dragonflies. They rival the butterflies and moths in beauty, form and color.

They are a welcome sight because, for one, they are mosquito-eaters. Common white-tailed skimmers, 12-spotted skimmers, and green darners are but a few of the species on the wing. To get into the activity of dragonfly watching, or "dragonflying," it helps to have binoculars that focus under 10 feet, plus a good identification book such as "Dragonflies of the North Woods" by Kurt Mead, of Finland, Minn.

Dragonflies are relatively large and often beautifully colored insects that spend much time on the wing in darting and rapid flight. An expert hunter, the dragonfly has a streamlined body and glistening wings that carry it through the air at speeds of 30 miles per hour or more; each pair of wings strokes alternately, the front pair going up while the hind pair is going down, at a rate of 30 or 40 strokes per second. Like hummingbirds, dragonflies can hover in the air or suddenly dart in multiple directions. While sunning and resting, they extend both wings as if in flight.

Nymphs of dragonflies are aquatic and live in ponds or streams where they feed on insects. The spiny legs of the adults form a sort of basket under the thorax for catching prey. The head swivels easily on the slender neck, and the huge compound eyes can see in nearly every direction, enabling the dragonfly to catch insects of all sorts such as mosquitoes and gnats in the air.

Jim Gilbert taught and worked as a naturalist for 50 years.