Dragonflies rank high among the world's most successful animals.
They've had a long time to hone their skills. The first dragonflies took wing some 250 million years ago, during the Permian period. These predatory insects snatched lesser bugs over the backs of dinosaurs, and have long outlasted those giant extinct reptiles. The Odonata - damselflies and dragonflies - have diversified into about 6,500 species and occupy nearly the entire globe.
Many species of dragonflies are uncommon and local, tightly tied to very specific habitats, while others are widely ranging generalists.
Article Photos
This photo from the Ohio Division of Wildlife shows a wandering glider emerging from its nymph.
Perhaps the most adaptive of all is the wandering glider, Pantala flavescens. This large dragonfly occurs across more of the planet than any of its kin and is found on every continent but Antarctica.
Perhaps you have noticed large, tawny-yellow dragonflies effortlessly floating between cars stuck in traffic, over yards and fields or around the parking lot. These are most likely wandering gliders, and there are plenty of them on the wing right now.
Occasionally, one will hover over a parked car and dab its abdomen tip at the shiny paint. Female gliders are sometimes fooled by glistening cars, and think the paint is water. It looks as if the wandering glider is "stinging" the auto, but she's actually ovipositing, or laying eggs.
Glider eggs deposited on car paint won't fare well, but fortunately most are dropped in water.
An egg eventually spawns a strange alien-looking nymph. This larva lives a completely aquatic existence, feeding voraciously on lesser animal life. In as little as two months - incredibly brief by dragonfly standards - the glider nymph is ready to commence an amazing transformation.
Under cover of darkness, the nymph clambers from the water and affixes itself to a plant or other structure. Its shell begins to rupture, and the young dragonfly hidden within starts to push forth.
After an hour or so of struggle, the young dragonfly pops free of its larval case and begins pumping fluid through its veins. Its wings rapidly expand, and the body quickly hardens and changes from bland greenish-brown to the tawny tones of the adult.
By morning, the dragonfly is ready to spread its wings and take up an aerial existence. It'll cover a lot of ground over the course of its lifespan of several months.
An adult wandering glider is a master of the sky, its aeronautic prowess rivaling anything with wings. Small wonder this species has successfully colonized most of the globe.
Seemingly casual flicks of its wings send the dragonfly sailing effortlessly along, its lazy glides punctuated by blindingly fast bursts of acceleration and abrupt jigs and jags. Each time the glider darts, it is capturing some hapless flying victim, and that includes horseflies and other biting insects.
Like many birds, wandering gliders are highly migratory, but the dragonfly's movements remain somewhat of a mystery. Their known feats of migration can be spectacular.
Sometimes large swarms, numbering into the dozens or even hundreds, materialize. These "flocks" presumably are headed to warmer climes before the onset of cooler fall temperatures. Migrant wandering gliders have turned up on ships hundreds of miles at sea and at elevations of 20,000 feet in the Himalayas.
Millions pass through the Maldives Islands in the Indian Ocean, on a 1,100-mile roundtrip between India and Africa.
The rapid reproductive cycle of the wandering glider, coupled with its extraordinary powers of flight, has enabled this insect to become one of the most widespread animals on earth. Those cool looking yellow dragonflies swirling around the parking lot may travel further than you do over the next few months.
Jim McCormac is a wildlife specialist with Ohio Division of Wildlife.
