Dragonflies might be the least understood insects on the planet. They have been called the Devil’s Darning Needles, Mule Killers, and Snake Doctors. For an insect that has been around since before the dinosaurs roamed the earth, surprisingly little is actually known about them. Community Voices producer Renee Wilde went in search of answers to why a dragonflies form a huge swarm on her farm in Ohio every year.
It’s early evening and I’m out cutting the grass on our small farm. With each pass of the mower, more and more dragonflies appear all around me feeding on the small bugs that are being stirred up, until the air is thick with hundreds of with these silent, flying insects. I turn the mower off and sit quietly, listening to the sounds of the late summer and enjoying the aerial acrobatics of one of the oldest species on earth.
This is an annual event we see every year on our farm towards the end of summer, but I know nothing about this phenomenon. To learn more I turn to the internet, where I find a blog by the Dragonfly Woman, Chris Goforth, head of Citizen Science for the North Carolina Museum of Natural Science.
Chris saw her first dragonfly swarm in 2009. She wrote about the experience on her blog, and soon other people were sharing their encounters with dragonfly swarms and wanting to know more about it, "And I had been looking through the scientific literature and there wasn’t a huge amount of information out there. And so if you start collecting those stories from people, that would be a way to study something And I completely, accidentally created a citizen science project."
The term citizen science came up a lot when I was researching dragonflies.
"I like to think of it as a partnership between the public and professional researchers where they are working together to answer scientific questions," says Chris. She started collecting information on dragonfly swarming on her website in 2010. "And then I also give people the opportunity to tell me just kind of how they felt about that experience, and I think that is just something that I absolutely love about this project, and hearing stories of how people responded to that."
On a swelteringly hot day I head a metro park outside of Columbus, Ohio to meet up with a local dragonfly expert to learn more about my swarm. Bob Glotzhober is curator Emeritus of Natural History, from the Ohio History Connection, and he was the instigator of the Ohio Odonata survey in 1991 that was a statewide survey of dragonflies and damselflies.
Bob and I walk down a gravel path through the woods that leads to the Big Darby Creek, and he describes a feeding swarm to me, "The greatest number of these are the common green darners, which are about, 3 - 3 1/2 inches long. And their just swooping and darting. And most of the time unless you get the light just right you can’t even see what their eating. But their obviously diving after insects and gobbling ‘em up.
They have hairs on their legs, and while their flying they take those six legs and kind of form them into a basket, and will catch these things in that basket of the legs and pull them up to their mouth.
Now when you get migration swarms, that’s another whole different thing. You have dragonflies, large numbers of them, flying in one same direction constantly moving, very little variation and huge swarms."
How huge? Bob describes one that a naturalist in Akron witnessed, "Conservatively, somewhere between five hundred to a million dragonflies."
At the bottom of the trail, we reach the a beautiful, clear-running stream lined with trees and rocky outcroppings. Two kayakers paddle past, and a family with young boys are fishing on the bank.
"It’s one of the more pristine warm water streams in the state," says Bob. "There are a number of endangered freshwater mussels and a couple of rare fish that live here and lots of interesting dragonflies as well. Oh here’s a dragonfly! The more you start getting into them the more hooked you get with them. Their just really exciting animals. We have 165 species in Ohio and we really don’t know that much about them.
And one of the interesting ones is the common green darner, which is all over the place. The ones that we see here in Ohio, some of them when they emerge in the summertime here, when you get to the end of August, early September, they start gathering into these swarms that we were talking about earlier, and they migrate. And we don’t have a real good handle on it yet. But we think they migrate to the Gulf of Mexico.
So we know there’s this migration taking place, there’s maybe as many as a dozen species of dragonflies that do this. But again, working out the details of it, they’ve got it worked out really good with the monarch butterflies, but we’re a long way from that with the knowledge about the green darner and the other migratory dragonflies.
There are several ongoing citizen science projects aimed at learning more about dragonflies and their behaviors. You can find Chris’s Dragonfly Swarm Project online, and Bob is a member of the Dragonfly Society of the America’s which currently has two citizen science projects: Migration Monitoring and a Dragonfly Pond Watch.