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Let There Be Dragons!

Summer 2004 Newsletter

It’s a quiet, sultry summer afternoon and the flies and sweat bees show no mercy to human or animal alike, but help is on the way.

On wings of glistening gold or silver lace speeds a dragon of dread, the exceptional predator of mosquitoes, flies, gnats, and many other insects, the Dragonfly.

Dragonflies and their smaller relatives the Damselflies make up the order Odonata. This fascinating and colorful insect family consists of almost 5,000 species world-wide with over 400 found in North America. Males of many species are the most colorful.

These predators seize smaller insects with their strong, spiny, forwardly directed legs and consume them with their well developed biting mouthparts. They are appropriately named, for Odonata means “toothy ones."

Illinois River Cruiser, Halloween Pennant, Blue Dasher, Unicorn Clubtail, Prince Baskettail, Dot-tailed Whiteface, Wandering Glider, Skimmers, Darners, Bluets, Saddlebags, and on and on — don’t you love the names?

The Saddlebags have a large black patch at the base of their hind wings, suggesting saddlebags. Illinois River Cruiser (Macromia illinoiensis) is 2-2/3 inches long, a handsome large black and yellow dragonfly with bright green eyes. The Darner group includes our largest native species, reaching 3-1/2 inches in length. An Australian dragonfly is the world's largest, with a wingspan of 6-1/2 inches.

Dragonflies have large compound eyes that cover most of the head. They have short, bristle like antennae and a long, thin abdomen. The species has two sets of veined wings, the forward pair of somewhat different shape than the hind wings. Their flying ability rivals hummingbirds, and the are able to hover, fly forward, backward, stop quickly, change direction, and fly upside down. No wonder dragonfly maneuvers have been studied by aircraft designers.

Damselflies resemble dragonflies but are smaller and more slender. When at rest, their wings are held together above the body. Brightly colored damselfies include the Bluets, of which there are 35 species. Many are strikingly blue, but they are also red, orange, yellow, or lavender. The Violet Dancer lives up to its name. Another common eastern damselfly is the American Ruby-spot, reddish with a bright red spot at the base of its wings.

The male dragon patrols long stretches over water, and both sexes forage low and fast along dirt roads and trails and up and down long rows of corn. In cooler weather, they can reach speeds of 50 to 60 miles per hour.

They rest by hanging vertically, usually high in trees. After mating, eggs are laid in aquatic vegetation or on the surface of a pond or slow moving stream, and hatch from about 10 days to up to several months for species that must survive a cold winter or long dry season.

The larvae have internal gills, and when water is forced out under pressure, they jet-propel themselves through the water. The nymphs are totally aquatic and feed on other insects. They have a jointed structure that covers the mouth like a mask when not in use, but thrusts forward very quickly to catch prey in a pair of terminal hooks at its apex. This lower lip can shoot out in 1/100th of a second to as much as 1/3 the body length.

Nymphs molt many times, and get more active as the days get longer and the water warmer. They soon climb out of the water to begin their short adult life. While clinging to vegetation, they dry in the sun, and the magic begins. Their backs crack open, and an adult dragonfly is “born," the delicate exoskeleton still grasping it’s perch. Blood pumps through wing veins, the body hardens, and soon this amazing insect takes to the air, breeding soon after emerging, mating on the wing. Their purpose in life over, they die in approximately one month, or up to nine months for a few species.

Dragonfly watching can be a delightful pastime. If you’re observant, you’ll notice some dragonflies are habitual and return to the same spy-hunting perch again and again. Close-focus binoculars are best for viewing and a butterfly net or dragonfly net will permit you to study your catch — if you’re fast, and lucky!

Gently grab the insect by the wings and fold all four together over the insect's back with your thumb and forefinger. Unlike delicate butterfly wings, which lose scales when touched, dragonfly wings are quite sturdy. The larger dragonflies attempt to bite when handled and can inflict a painful pinch, but they do not sting. Release them soon so they can return to their beneficial work.

The March 2004 issue of Audubon magazine reported that a 120-acre property in New York, now part of the Hunt-Parker Sanctuary, has attracted 29 Odonata species. How many might we have in Jo Daviess County? Habitat is disappearing for insects too, and many species of dragonflies are at risk of extinction.

A good way to learn more about these fascinating insects is the first nationwide dragonfly “bible,” Dragonflies Through Binoculars: A Field Guide to Dragonflies of North America by Sidney W. Dunkle (Oxford Press, $29.95). This book is packed with information. But I think the Stokes’ Beginners Guide to Dragonflies ($8.95, Little, Brown) has better photographs and is easier to use. It’s also a more convenient size to take into the field and it has a nice breakdown of families, habits at a glance, and a color-code inside the front cover describing more than 100 species. There are a few other dragonfly books available. Ask the friendly folks at Wild Birds Unlimited, Galena, to order one for you, or check Amazon.com. The newsletter Argia is a quarterly by the Dragonfly Society of America and a video called ‘Common Dragonflies of the Northeast’ is available as well.

Go to http://www.dragonflies.org/ for photos, catalog, how to handle, supplies, dragonfly museum, and more, and examine a larger than life view of their amazing eyes, bodies, and wing patterns.

— Grace Storch

Editor’s Note: If you want the bibliography, Grace used Peterson Field Guide to Insects, Larousse Encyclopedia of Animal Life and Bird Watchers Digest (July/August 2003) along with the two above mentioned dragonfly books.