Chasing Dragonflies and Damselflies
Birding and butterflying have long been popular. With the advent of easy-to-use field guides and common, colorful names like neon skimmer and thornbush dasher, the pursuit of dragonflies and damselflies is finally taking off.
Some birders travel to new places, even far-off countries, to add to their life lists. Others might swap their avian field guides for new quests. Butterflies, perhaps. Or, like Thomas Cullen, dragonflies.
Cullen converted several years ago while hawk watching with friends on New York's Long Island. He noticed swarms of dragonflies flying along the same coastal migration path as the birds of prey. Thousands of green darners head south en masse in the fall, covering up to 100 miles in a day. Hawks, particularly American kestrels, follow along and dine on dragons as night falls. Trained as an entomologist, Cullen was accustomed to identifying insects under a microscope--fine for work but not to his liking for a hobby. When he learned that dragonfly field guides were available, he thought, "I could really do this."
And has he ever. Cullen, a retired biologist who substitute-teaches in the Adirondacks, has spent hours slogging through New York's bogs, ponds, and rivers recording sightings and taking photos for a five-year, statewide survey of dragonflies and damselflies--members of the insect order Odonata, or "odes," as enthusiasts call them. The survey turned up five species never before recorded in the state, including the broad-tailed shadowdragon--an elusive creature that flies at dusk over fast-running rivers. "You see them by looking upstream, so they are backlit by the setting sun," Cullen says. "You see their shadows." The species was only first described in the 1990s in Canada. "It's kind of neat to think that right here in the Northeast a new species can be discovered." On average, one new dragonfly species per year is discovered in North America.
[gallery:55086|align:left|caption:GALLERY See more dragonfly photographs.]
Similar surveys are taking place across the country as ecologists recognize that the colorful insects are excellent barometers of environmental health. At the same time, after long lagging behind watching birds and butterflies, dragonfly watching is catching on now that there are easy-to-use field guides and common, colorful names like neon skimmer and thornbush dasher. Just as with birding, hobbyists range from casual observers to hard-core enthusiasts.
Cullen took me on a hike in the Adirondack Mountains to see some early spring species. The sky was a dull heavy gray--poor conditions for spotting the sun-loving insects--and as we traipsed through a powerline cut, Cullen spied a dragonfly perched on a sandy patch of ground. He placed his net over the bug and reached under to gently grasp its wings, which made a dry papery sound. (Enthusiasts quickly come to identify many common species by eye, but some require an up-close look at intricate markings on the body and tiny appendages on the abdomen.) When one wing slipped out of his hand, he let go and started over. "I don't want to damage its wings," he said. "If I do, it's as good as dead."
He passed me the dragonfly and we worked through the identification. When the beast, seemingly resigned to my holding its wings, curled its long abdomen, I noted the spiny hairs on its legs. I measured the body length (42 millimeters) as Cullen opened his field guide to the corporals. "They're known for perching on the ground and for the white stripe on the thorax," he said, explaining his shortcut. He read an entry while I checked the tiniest details with a hand lens. With dark spots at the base of the wings and black-and-white shoulder stripes, we pegged it as a female chalk-fronted corporal--the first species on my list. I touched its legs to my hand and released the wings. She stayed perched long enough for me to exhale and truly admire her--and for Cullen to snap a photo.
Dating back more than 250 million years, odes were around long before the dinosaurs appeared. Since sharing the earth with humans, they have been compared to helicopters, because they can hover in midair, and to horses, as the devil's mount. Western cultures tend to imbue odes with evil powers; in Japan, on the other hand, they're symbols of happiness and courage.
Odes are easy enough to find at a pond or stream around midmorning, after the sun has warmed the air. They fly and perch, hunt and mate, from spring until fall. (You can tell a dragon from a damsel by its wing position when perched: Dragonflies hold their wings straight out to the side, while damselflies partly spread their wings or fold them together behind them.) Only a few species migrate; most overwinter in the larval or nymph stage. The larval stage for North American species is entirely aquatic, so many odes both emerge from and lay their eggs in water.
Stunning jewel-like colors and daredevil flying are reason enough to give dragonflies a look-see, but federal and state agencies use the presence of certain species as indicators of clean, highly oxygenated waters. "They're the trout of the dragonfly world," says Larry Federman, of clubtails, named for the widening abdomen end that resembles a club. "They need pristine, fast-flowing water." Federman, the education coordinator for three Audubon New York sanctuaries, got involved with his state's survey when he was looking to develop a nature program for New York City high schoolers, many of them minorities from immigrant families.