Dragonflies: Unsung heroes of summer
By By Gail Barton / horticulture columnist
Aug. 9, 2002
I hear a lot of talk about butterfly gardening. Everyone seems to want to attract more of these colorful, lovely insects to the garden.
There's nothing wrong with gardening for butterflies. I just think dragonflies and their damselfly cousins deserve equal time.
Dragonflies are usually found in sunny areas. Damselflies, on the other hand, like shaded woodlands. I enjoy watching them flit though the woods from my creekside deck. When resting, a dragonfly spreads its wings. Their diminutive relatives, the damselflies, usually hold their wings vertically and to the back.
Like butterflies, dragonflies and damselflies can be quite colorful. Their bodies can be electric blue, metallic green, purple or red. The wings are transparent and are very efficient.
Dragonflies are swift flying up to 35 mph. They are agile capable of reversing direction in midair, flying backwards or hovering. They catch prey on the wing and even mate in mid-air. The U.S. Navy and Air Force have funded research to look into why dragonflies are such powerful flyers.
Adult dragonflies are successful hunters that live near water. Their success as predators is partly because they are such accomplished flyers. Their alertness and ability to spot prey also factors into the equation. A dragonfly's head rotates freely and is distinguished by bulging compound eyes that excel at detecting movement. The mouth has powerful chewing jaws with teeth-like projections.
I've read that the dragonfly's prehistoric ancestors had wingspans of up to 30 inches. Modern dragonflies have slender bodies that average 1 to 5 inches long. The body has long, strong legs designed to hold prey captured in flight. After a successful hunt, they pause to dine on a "fast food" entre that often consists of a mosquito or biting fly.
Adult male dragonflies claim a territory and fight other males to defend it. After mating, females deposit eggs on or near water. The eggs hatch into a nymphs or naiads.
Naiads are actually teen-aged dragonflies, but they look nothing like their parents. The naiads are aquatic predators. They live entirely in the water feeding on mosquito larva, tadpoles and even small fish. They breathe through gills on the rear of the abdomen. When hunting, the naiads lie in wait buried in silt or screened by vegetation. When prey comes near, they shoot a powerful stream of water from their abdomens and are quickly propelled from hiding.
Naiads can also extend a specialized lower lip with lightning speed. The lip has bristles that can grasp a mosquito wiggle-tail and pull it into the mouth.
During its time in the water, the naiad eats voraciously. As it gains weight, the skin is shed several times. Eventually naiads climb out of the water, shed their skin one last time and emerge as adults.
They say that adult and naiad dragonflies are the most effective mosquito-hunters. They eat many more mosquitoes than their mortal enemy, the purple martin. I've heard that purple martins eat more dragonflies than mosquitoes. I'm glad dragonflies and damselflies are fighting on our side. They are colorful and definitely entertaining. I enjoy watching them in my garden and in natural areas.
Maybe "Gardening for Dragonflies" is not a popular gardening topic because it's just too simple. A normal Mississippi summer will provide plenty of the hot muggy weather dragonflies crave. And as any gardener who has a small pond will tell you, "Supply some water and they will come!"
