Bright colors whiz past you. Out of the corner of your eye you notice something hovering. Then it darts forward, backward, up, and down. Is someone playing with a remote-control helicopter? No, it’s one of nature’s aerial acrobats: a dragonfly.
Brilliant hues and interesting names characterize these large summer insects. A Ruby Meadowhawk’s body glows bright red in the sunshine. Green Darners sport a bright green thorax and a turquoise abdomen with a black dorsal stripe. A male Calico Pennant has a black-and-red striped thorax, a black abdomen with red triangles, and black spots at each wing tip. Its female counterpart is yellow and black. The color variety goes on and on for the 25 dragonfly species that are found in the Great Lakes Bay Region.
Midday is the best time to watch dragonflies flying near ponds, marshes, or lakes. Each of their four wings moves independently, enabling them to maneuver horizontally, vertically, forward, and backward, depending on their wing angle. The large muscles within a dragonfly’s thorax provide flight power. Some dragonflies have been clocked at speeds of 30 mph, although a usual flight around their habitat is at a speed of about 10 mph.
Patrolling is a behavior you may see while watching male dragonflies. A male will fly in a meandering path, searching for food or females, and then will return to one of his desired perches. Males are seen more frequently than females. Females are seldom seen except for when they mate or lay eggs.
Males will choose a section of water shoreline to call “home.” They defend this area from other males by chasing the intruder away. Males signal their dominance by raising their abdomen from a horizontal position to a 70 degree-angle, similar to a gymnast doing a handstand.
The best opportunity for photographs happens when dragonflies perch. Many perch vertically or at an angle on a branch. Other species hang straight down, and a few perch horizontally. Skimmer dragonflies exhibit all four perching styles. They also rest horizontally on the tip of a stem, like an acrobat balancing on a tight rope.
People pleasers. Dragonflies benefit humans because they consume insect pests such as mosquitoes, gnats, deer flies, horseflies, blackflies, and midges. They don’t bite humans or transmit any diseases.
Eyesight experts. A dragonfly has large compound eyes with thousands of lenses, enabling it to view 360 degrees as well as up and down when it turns its head.
Hungry hunters. When prey is spotted, hungry dragonflies dart off in hot pursuit and capture it while flying. The bristly hairs on a dragonfly’s six legs form a catching basket, while the tarsi (similar to our feet) grasp the insect prey, moving it skillfully to the dragonfly’s mouth at the front of its head. A dragonfly’s serrated mandibles chew sideways (not up and down like our teeth) between its flap-shaped upper and lower lips, which are called a labrum. Dragonflies, besides eating pesky insects, may also consume butterflies, moths, ants, and even other dragonflies if they are within flight range.
Aquatic animals. Clean water is a necessary habitat requirement. Dragonfly eggs are laid in water and hatch into aquatic nymphs (also known as naiads). A nymph undergoes 10 or more molts before crawling out of the water onto a plant stem, emerging as an adult. Nymphs breathe with gills and are also voracious predators of aquatic insect larvae, crustaceans, and small tadpoles.
Interesting insects. Scientists place dragonflies in the suborder Anisoptera, meaning “uneven wings,” because their hind wings are broader than their forewings.