Common. Migratory population. Believed by some that we have both migratory and non-migratory populations. The latter adults will die off at the end of the season, while the nymphs will overwinter. Migratory dragonflies move south.
This species possesses fat stores for migration, and their direct flight muscles are known to contain the smallest mitochondria of any creature. Migratory individuals begin moving south in the late summer. Their offspring return to the north in the spring. They can fly as far as 87 miles per day. Often eaten by kestrels as the migrations coincide spatially and temporally. To overcome MN cold when they return in the spring (they are often the first dragonflies to emerge), the green darners shiver their wings and large flight muscles in the thorax, raising the insect’s temperature to approximately 110oF.
Average 3 in. long, the arboretum’s largest resident dragonfly, and the second largest in MN (the first being the Dragonhunter).
On the wing longer than most other species due to migration, and can be found mid-April through mid-October
Description: Males are very distinctive in that they have no thoracic stripes whatsoever, and their thoraxes are solid, bright green. Males have a bright blue abdomen with a dark purple stripe running the length of the top. Females share the green thorax, but their abdomens grey with age. Abdomens are thicker than most darners. Both sexes have a distinctive bull’s-eye pattern on top of the face. Eyes are typically grey, and there is a thin yellow stripe along the posterior rim. Wings are clear with a small yellow spot near the tips. Juveniles have green thorax, but the abdomen is quite variable, from a dull violet to brown or red.
Prefer pond or lake edges (still water), shallow streams, preferably fishless. They have been found over the prairie in the Arboretum in large swarms. Likely a migratory group. They tend to perch vertically. Eggs are laid while the pair is still connected, as the male seeks to guard the female should another individual try to scoop out his sperm. This is the only species of darner to oviposit while still coupled. The eggs are deposited in plant stems below the waterline, and the creatures spend several years as nymph before emerging to metamorphosize.
During mating, some males will ram coupled dragonflies in mid-air to try to free the female (in order to mate themselves).