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Speaking of Nature: A flying friend on the water

  • A male common green darner lands in the foreground. Behind him, a female (in tandem with the male) dips her abdomen into the water to release her eggs. For the Recorder/Bill Danielson

  • A dragonfly nymph shell, now empty, sits on the leaves of aquatic plants floating on the surface of a pond. For The Recorder/Bill Danielson

  • DANIELSON



For the Recorder
Monday, July 09, 2018

Now that summer is in full swing, I thought I might spend some time focusing my attention on topics that are iconic for the season. Specifically, I’m talking about heading to a lake or a river in an attempt to beat the heat. What could be more relaxing than taking a refreshing dip? Interestingly enough, there is plenty of opportunity for nature observation even when you’re taking a break.

Lakes and ponds, rivers and streams are all natural areas filled with all sorts of living things. When I was a boy, my parents would pack up the family and head over to Laurel Lake at the Erving State Forest. I still go there from time to time, but these more recent visits simply cannot compete with my childhood memories. Those were the golden days of my youth.

I particularly enjoyed swimming in Laurel Lake because there were wild things just outside the ropes of the swimming area. In the evenings, when the crowds were starting to thin out, I could float along like a beaver with only my nose and eyes out of the water, and I could get wonderful low-angle views. My favorite creatures to observe this way were dragonflies and damselflies.

Both of these insects are members of the order Odonata, and are characterized by elongated, slender abdomens in the adult forms and very long wings. Ancestral forms of this group have existed since the Carboniferous period (about 325 million years ago) when the surface of Earth was dominated by great swamps. Back in that time, one ancient ancestral species grew to be the largest insect ever to live. It had a wingspan of about 30 inches and must have been a terror to other flying insects. This giant was not able to survive the mass extinction that came at the end of the Permian, and it disappeared.

The basic difference between dragonflies and damselflies has to do with the way they hold their wings. Dragonflies tend to keep their wings in a lateral plane stretched outward from their bodies and perpendicular to their abdomens. Damselflies, on the other hand, tend to hold their wings together above and parallel with their abdomens. This is the most superficial and simplistic way to separate the two groups, but it works.

Both groups are closely tied with water. Most species must lay their eggs in fresh water where they can hatch and grow in their larval stage. Mating is a tricky affair (more on this topic in future columns) that requires the male to grasp the female by the head. The female will then exend her abdomen under the male’s body and receive a packet of sperm with which she can fertilize her eggs. Then the pair (known as a “tandem”) will find a good place to deposit the eggs in water.

The eggs quickly hatch and the young, known as “nymphs,” become rather ferocious predators that patrol their aquatic habitats and strike out at their prey with extendable jaws. Larger species of dragonflies can spend five years living in this underwater stage, but eventually the need to reproduce will drive the nymph to the surface. The nymph’s shell will split along the back and allow the familiar adult form to emerge, pump fluids into its wings to expand them to full size and then “cure” in the dry air. This process often happens at night to afford the vulnerable creature some protection from predators.

Once the wings have dried and hardened, the carnivorous diet of the dragonfly is aimed at other flying insects. Mosquitoes are frequent targets of both dragonfly nymphs and dragonfly adults, so be friendly to them whenever possible. They are on our side!

As for the name “dragonfly,” I was particularly impressed when I read the story of the origin of this name. According to tales of old, a soldier (who would later become known as Saint George) fought and conquered a dragon. He performed this service as a mounted knight and in revenge, the devil transformed his beloved horse into a giant flying insect. In Romanian, the word for “devil” is “drac” and the word “dragonfly” (or is that draconfly?) means, “devil’s horse.”

In pursuit of this general topic, I have scoured my archives for dragonfly photos and have identified several pairs of male and female photos of different species. So, I shall expand upon different aspects of dragonfly life while also presenting more detail on particular types of dragonflies and damselflies in my next few columns.

In the meantime, get outside and see if you can find a dragonfly of your own. They are surprisingly widespread and there is something beautiful about each species.

Bill Danielson has been a professional writer and nature photographer for 20 years. He has worked for the National Park Service, the U.S. Forest Service and Massachusetts State Parks, and currently teaches high school biology and physics. Visit www.speakingofnature.com for more information, or go to Speaking of Nature on Facebook.