Dragonfly 101

These dragons don’t breathe fire, and they pose no harm to people.

In their short time alive on the fly, they radiate a beauty and charm that complement butterflies. Dragonflies provide a dandy sight in many places, not only across the Grand Strand, but across the continent, even into Quebec’s Laurentian Mountains. At this time of year, they might be seen in a garden, crossing a highway, or passing by a patio for a rest on the shirt covering someone’s shoulder.

“They really are an important part of the ecosystem with a interesting life cycle that most people don’t know much about,” said Brian Williams, a Clemson University field technician who grew up “interested in insect genetics.”

Walking last month by Kimbel Pond at his swamp-filled workplace for the past decade, Hobcaw Barony, just north of Georgetown, he explained how dragonflies are aquatic insects, which based on the species, spend about one to five years as nymphs with gills, then once they molt, with wings, live outside water, but just for a few weeks or months.

“For most of their lives, they’re under water,” Williams said, pointing out their purpose when finally airborne, “like most insects ... to mate and lay eggs.”

As adults, dragonflies’ main role, Williams said, entails eating harmful insects. Like houseflies and horseflies, they have acute, “nearly 360-degree vision” from compound, “big bulbous” eyes, with thousands of lenses each, carried from the nymph stage.

Flying, dragonflies really stand out, using different configurations of their four wings, like a helicopter or Harrier jet, Williams said, and “better than anything humans can build.” They can flap their wings together, individually, and in an alternating pattern, to move up, down, change pitch in a pinch and dart around.

He called them “amazing fliers,” and on the hunt for other flying insects, including mosquitoes, “they have have to be fast and agile in the air to be able to capture them.”

“Twelve miles an hour is approaching the top end of speed for some species,” he said in response to my reported thrill of seeing dragonflies fly astride and parallel with a bicycle for a few seconds with second-nature ease, “however several larger species of dragonflies can reach up to over 30 mph.”

The wings cannot get wet, though, for dragonflies cannot take off easily if they fall in water, Williams said, so during rain, they seek shelter under a leaf or branches, otherwise the wings need to dry out.

Territorial, for food, mating

Standing on a dock, Williams watched two green dragonflies in what appeared to be a chase, “probably two males” vying for space along the pond’s edge to forage for food and a good place to mate with females who will lay eggs in the water, or on shoreline vegetation, to drop in.

Dragonflies need proximity to water, and some types like it stagnant, others flowing. Either way, Williams said, the nymphs grow as “good hunters” of “anything they can grab,” including aquatic worms and bugs, as well as minnows and tadpoles.

As nymphs, dragonflies fall prey to waterfowl, and in the air, become feasts for praying mantises and wasps, Williams said, amazed how the juveniles don’t resemble adults past the head. Although not active pollinators, dragonflies could be “passive” ones, only if the material graces their three pairs of legs and lands elsewhere.

Impressed by dragonflies’ speed and skill in the air, Williams said they continue diurnal living from their underwater world, and boast extra senses from seeing “infrared ranges and colors we can’t see” and an enhanced attraction by scent.

The “power of numbers” rule with egg deposits, with a few hundred each, Williams said, “because of so much predation,” and the hatchlings that survive to develop prove resourceful by hiding under roots and objects in the water, because their parents “are not around, or not even alive to guide them along.”

Christopher Hill, a scientist in Coastal Carolina University’s biology department, agreed about the sensitive, precarious journey a dragonfly nymph makes to graduate to adulthood.

He said in that transition, after maybe several years in the water, a dragonfly nymph faces immense odds to make it “through that 1-2 hours” to the shoreline and cattail stems after molting with wings, to get out of the “larval shell just right” in “that one chance,” because a rainstorm can ruin those fresh, soft wings,” and the end to the vulnerable insect’s existence can arise so suddenly when “picked off by a bluegill,” heron or a red-winged blackbird.

“Birds pick them up to feed them to baby birds,” Hill said.

On a stroll on campus last week, Hill ran into a reminder that dragonflies deserve a better reputation. One such bug inadvertently prompted a student “to jump backward,” he said.

“People don’t know that they’re harmless,” Hill said. “High-quality photography helps people appreciate how beautiful that are.”

Thrill of identifying local species

Hill, a longtime birdwatcher involved with national bird counts, has found his delight with dragonflies as “a pretty serious hobby,” especially in identifying less common varieties.

“There’s something in the thrill from finding something never seen in Horry County before,” Hill said.

He remembered the tally of 52 dragonfly types on record in this county when he digressed in this pastime a few years ago, “and this summer, I found the 100th species” – Coppery Emerald (Somatochlora georgiana), “a very elusive species, only the second time documented in South Carolina that I know of.”

“It’s nice to know how much diversity is out there,” Hill said, noting the various habitats across the area.

Hill said in coastal spots, dragonflies might be seen “every month of the year,” whereas in Conway, the latest observation might reach into early November. Common green darners might be seen “right through Christmas and New Year’s in Georgetown,” though. Typically, “the very earliest species” emerge in late February or early March.

Each species has its own special needs, whether by the Waccamaw River, or in “any retention pond, in any neighborhood,” but all are dependent on “particular aquatic habitats.” He has found that “the wildest, most beautiful rivers and swamps” provide viewing for “the most distinctive dragonflies.”

Hill underscored how dragonflies’ lives embody “a lot more under water than what you see flying.”

That huge family of several thousand species globally in the Odonata order also includes damselflies, whose nymphs are considerably smaller and thinner than those of dragonflies’, Williams and Hill each noted.

To distinghuish between dragonflies and damselflies, think of an analogy to moths and butterflies, Hill said.

Dragonflies rest with their wings open, like moths, and damselflies hold their wings closed together, as butterflies do.

When a dragonfly hovers or zips by, also know that you are seeing a marvel of nature in the pinnacle of its life so short once out of water – a wonder for the flier and us the admirer.

This story was originally published September 5, 2015 at 9:00 AM with the headline "Dragonfly 101."