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.
"Once you start watching dragonflies, you can't help but notice how amazing they are," he says. They fly at speeds of up to 30 miles per hour, zip forward and backward, pivot in a flash, and hover with ease. They prey on live insects in midair, snapping up small bugs with their mouths or grabbing larger ones with their legs, then perching to devour them. Says Federman, " 'Dragonflies are your friends,' I tell the kids. 'They don't sting or bite--they're flying around trying to eat the bugs that will bite you.' And catching them is half sport and half science. They are a most ideal critter for Audubon's mission of connecting people with nature."
And while the variety is great, the number of species isn't overwhelming. "There are more than 450 bird species in New York, versus 50 to 60 species of dragonflies in any one area" depending on the county, Federman says. He learned all the common species in one season, although he admits some IDs still elude him.
Even experienced enthusiasts and trained entomologists say there's still plenty to learn because so many questions remain. For instance, no one knows where migrating green darners winter. And it's not clear why different species select specific habitats when they aren't choosy about what they eat. "I reckon today the state of knowledge is about where birds were in the Civil War," says Nick Donnelly, a renowned expert and cofounder of the Dragonfly Society of the Americas, who lives in Binghamton, New York. "We're still finding new species in the Lower 48. And not limited to remote canyons but in the Delaware River, Wisconsin, and Arkansas."
Donnelly became interested in both birds and dragonflies as a teenager in Washington, D.C. "But there was no easily understood literature, no guides, no nothing," he says of odes. Donnelly was often stumped by the dragonflies he collected, finding them neither in insect books nor in the Smithsonian Museum's collection, which he studied extensively. ("They were very kind to me, gave me the run of the place," he recalls.)
That was his lightbulb moment. "I realized no one knew much about dragonflies," he says, especially compared to birds. "That's what really hooked me."
His contribution to the field has been indispensable. In 2003-2004 he published a three-part volume on the distribution of odes across North America, with dot maps, after compiling data from museum records and individuals. He's added several new species to the global list of known odonates, including a dozen or so from Panama and, in 2012, several from Vietnam.
Another pioneer, lifelong Cape Codder Blair Nikula, became fascinated with dragonflies through photography. "I started taking pictures of these things without having any idea what they were," he says. "There was nothing in the way of a resource for someone like me. Just thick, dense, technical tomes with descriptions based on dead specimens."
Nikula set out to photograph every species in New England and started publishing a newsletter. In the late 1990s Donald and Lillian Stokes approached him to coauthor an introductory field guide, part of the Stokes Beginner's Guide series. The guide, published in 2002, "was limited to around 100 species, which made it manageable," says Nikula. It emphasizes general field marks and behaviors for novice chasers. "One thing we tried to emphasize was to look at behavior," he says. "Perchers versus flyers, for instance. Perchers spend most of their time perched and just fly to get to the next spot, catch food, or defend territory. Also the way they perch--horizontally or vertically."
Today there are field guides for many regions, some specializing in damselflies, some focusing on identifying odes through binoculars. Enthusiasts also visit websites to see photographs and join listservs to chat about sightings and opine about ode behavior.
Scientists are taking advantage of the growing interest in odes and putting all that enthusiasm to work. Many states, including New York, New Hampshire, Maine, Rhode Island, New Jersey, West Virginia, and Ohio, have launched surveys for the "pure and simple documentation of distribution--which species are currently here," says Erin White, a zoologist for the New York Natural Heritage Program who oversaw much of New York's five-year effort. Though it wrapped up in 2009, White continues to analyze the data for answers to some very basic questions. Little is known about why common species are common and rare species are rare, and she hopes to generate some hypotheses by relating distributions to specific habitat information. For instance, the subarctic darner, a three-inch-long dragonfly with a yellow face and blue or green stripes on its hefty, dark-brown midsection, was observed at only two sites, one during the survey, one just after. "We know they like sphagnum bogs, but we have a lot of bogs in the Adirondacks where it didn't occur," White says.
Three of the state's 59 damselfly species--the pine barrens bluet, the scarlet bluet, and the little bluet--were listed as threatened at the start of the survey, so extra effort was put into monitoring them. Indeed, while surveyors spotted some of the damsels at new sites, the three threatened species were limited to Suffolk County. They may be further threatened by land use changes in this heavily populated part of Long Island, including vehicle use near pond habitats and invasive plants such as phragmites that displace native shoreline species.
New Hampshire, meanwhile, has just finished its own five-year survey, says coordinator Pam Hunt, an Audubon Society of New Hampshire biologist. Hunt has records dating back to the 1800s, since prominent entomologists of the day, such as Samuel Scudder and Philip Calvert, did field work in the White Mountains. In studying the data on hand, she noticed something curious: Forty-six species--about one-third of those in the state--were listed as being of potential conservation concern. "That was the first justification to launch the survey," she says, invoking the common refrain of conservationists: "We can't conserve what we don't know."
Like White in New York, Hunt spent a lot of time training volunteers how to identify dragonflies and damselflies. A small cadre of them became quite dedicated. "They're what I call my nut jobs and crazy people, who drive all over the state, who spend their vacations doing this," she says, and I can almost hear her smile through the phone. "We love each other dearly."
As with birders, some dragonfly chasers keep life lists and treasure new finds. And those avian admirers who take to this hobby find new ways of observing their favorite places and new reasons to check out unfamiliar ground--especially wet habitats. Common predators of dragonflies included cedar waxwings and eastern kingbirds, so birders may also gain a new appreciation of the food chain.
Most of the newcomers are birders who are quite comfortable using their binoculars, though not necessarily nets. "Netting is a bit of a sport, worthy of stories around a campfire," says Donnelly. "Clubtails are the prize," he adds, because they're so hard to catch and have a short season. Walter Chadwick, from Yonkers, New York, uses close-focus binoculars to observe and identify dragonflies in the field. He also has a small DSLR camera to capture his quarry digitally. And although he sometimes carries one, he says, "I stink with a net."
Chadwick heard about the New York dragonfly survey and attended one of White's training sessions. "I just got hooked," he says. On a hot August day I joined him at a meadow in Harriman State Park, about an hour north of New York City. He swept his net back and forth, casting a shadow to spook out of hiding any perching odes in the waist-high grasses and goldenrod, but all we saw were large dragons flying overhead. Common green darners were recognizable by their metallic shimmer as much as their green and blue coloring. Many odes, such as darners and baskettails, fly quite high, which is when binoculars come in handy.
A clump of cattails revealed a small pond, no bigger than a puddle really, where Chadwick thought he spotted a spreadwing--a damselfly that doesn't fold its wings together above its body. He took a few snapshots and looked closely at his camera screen for the field marks he knows by heart. Blue eyes, yellow-blue stripes on the thorax, and no coloration on the tip of the abdomen: It was a slender spreadwing.
Part of the game is simply spotting a flying ode. After more than an hour and not much to show for it, Chadwick continued to patiently tromp through the grasses, sometimes entering the dappled shade under the trees, other times approaching a nearby stream. He pointed out another damselfly--just a tiny floating wisp, hard to distinguish from a broken fragment of pale grass. I'd see it, then lose sight of it again. Chadwick followed it gamely and noted its features aloud--yellow overall, some darker markings, about an inch long, very thin--before trying to catch it in his net. He missed, but it turned out he had seen enough. Back at the car, he checked his guide: "Tiny size and bright-yellow coloration of males are distinctive." A citrine forktail--species No. 90 or so on his life list.