“Tween” Male Blue Dasher Dragonfly

Subject: Dragonfly Behavior
Location: Faribault County, Minnesota
July 13, 2016 12:57 pm
On June 21 I was walking my Rain Garden to see if any insects were taking advantage of the blooming plants when I noticed a “blue” Dragonfly on top a stick I was using to mark a plant I had moved. Seems most of the dragonflies I see perch atop sticks or posts or at the end of branches. I’ve likened that behavior to “sunning” as I’ve seen butterflies do. The dragonfly might fly around a bit, but usually returns to the same perch, perhaps in a slightly different position.
This particular Dragonfly on that particular day landed horizontally atop the stick, then slowly raised its entire abdomen to a near vertical position (see photo). After a moment or two it flew around and then came back to the same stick and repeated the behavior. Fascinating!
If I were to guess, I’d say it was a mating call, probably with pheromones to cast on the breeze and disperse with fluttering. Male or female, I’d guess male. But that last photo reveals a groove along the abdomen which I hear in butterflies indicates females. So I’m uncertain as to what I photographed; still fascinated, but also uncertain. I’m hoping you can set me straight.
Nature is absolutely amazing when one takes the time to observe! Not just glance, but actually look and observe.
Thanks so much!
Signature: Wanda J. Kothlow

Blue Dasher
Blue Dasher

Hi Again Wanda,
Based on this BugGuide image, we are quite confident this lovely blue Dragonfly with red eyes is a “tween” male Blue Dasher,
Pachydiplax longipennis.  According to BugGuide, as they begin to mature, “tween” males are described:  ” they mature the abdomen becomes blue except for yellow that remains on the sides of the first few abdominal segments and the black tip on the end of the abdomen. The eyes at this stage are still juvenile red/grey.”  Now regarding the posture you observed, we found this comment by Ron Hemberger on a BugGuide posting:  “When it’s hot, dragons can be seen in an obelisking posture, with rear end elevated and, that way, less area exposed to the sun. The ones I’ve seen do this – different species than yours – typically have a bit of curl to the body, so the thorax is almost level with the ground while the abdomen heads upwards.”

Blue Dasher
Blue Dasher

Well now, this goes to show ya what little I know. I never would have thought the “obelisking” of the dragonfly was for thermoregulation! And here I was being all “scientific” and romantic and thinking of baby dragonflies in the making. I can certainly and honestly say I learned something new today!
Thanks, y’all!

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