Kankakee Sands Nature Notes
Learn about the many wonderful plant and animal species at Kankakee Sands in our monthly Nature Notes articles written by TNC staff.
Dragons of the Sky
Dragons are all the rage these days. Friends are fascinated by the beasts in Game of Thrones. My son likes the evil, fire breathing monsters that are to be fought, slayed and conquered in the game Dungeons and Dragons.
As for me, I delight in the dragons of the sky that that hover, glide and zoom over our Newton County wetlands, entertaining me on sunny summer’s day.
Evolving approximately 300 million years ago, dragonflies flew the skies when dinosaurs walked the earth. Fossil records show that at that time, dragonflies had a wingspan of up to two feet long. Today’s dragonflies are much smaller, with wingspans maxing out at five inches.
Across the world over, there are more than 5,000 species of dragonflies! Indiana is home to 97 of these species. Forty-four species have been recorded for Newton County with names equally as interesting as those in Game of Thrones and D&D: unicorn clubtail, Halloween pennant, ebony jewelwing, prince baskettail, eastern pondhawk, and black saddlebags.
Here in northwest Indiana, from May to the end of October, we can see dragonflies darting above sunny shallow ponds, ditches, slow moving open streams, and along the edges of shallow lakes. I see them regularly along the ditches, ponds and wetlands at Kankakee Sands.
My absolute favorite dragonfly is the twelve-spotted skimmer (Libellula pulchella). Remarkable are its aerial dynamics—it dashes over the water, stops, hovers, and dashes off again, often reaching speeds of 30 miles per hour!
The twelve-spotted skimmer is 1.5 to 2.1 inches in length, and as the name implies, the dragonfly has 12 dark spots on its wings. There are three spots on each of the four wings: 3 x 4 = 12, the math checks out! Both males and females have the dark spots. The males have an extra beauty mark - alternating white spots between the dark ones on their wings. The males also differ by having a blue abdomen (the abdomen is the long part that sticks out behind the wings), whereas females and juvenile males have chocolatey-brown abdomens.
Dragonflies have two extremely large eyes, which wrap almost completely around their head. Their eyes, each with approximately 30,000 lenses, coupled with their nimble flight skills, allow them to locate and capture prey with precision while flying. As the twelve-spotted skimmers fly by, you might happen to notice uneaten body parts of mosquitos, flies, butterflies, moths, mayflies, and flying ants being discarded as they zoom along.
Twelve-spotted skimmer males are quite territorial, and they aggressively patrol their breeding areas. Because they are so territorial, if spooked from a perch on which they are resting, they will dash off, and often return to the very same spot This is very handy when wanting to view a twelve-spotted skimmer. You can creep up to the dragonfly (as quietly as is humanly possibly when you are sloshing through a wetland) and should you accidentally scare it from its perch, it may well fly off and circle right back to the very same spot affording you a first-rate view.
Dragonflies don’t live long as adults. Once they emerge from the water, they get to the important business of finding a mate. Males have grasping structures at the end of their abdomen for grasping the head of the female. You can often see twelve-spotted skimmer males and females in this male-first, female-second attached position as they soar through the air together.
Mating takes place when the female bends the tip of her abdomen up under the male, creating a circle of dragonfly body parts. Once they separate, the female flies over the body of water within the territory of the male she bred with, touching the tip of her abdomen to the water, and releasing eggs.
Six-legged, large-jawed larvae emerge from the eggs. The larvae are green brown to blend in with their underwater surroundings to avoid being predated, and to better be able to ambush their prey of mosquito larvae, small fish and even tadpoles. As they larvae grow, they molt their exoskeleton, much like a grasshopper does. The larvae breathe underwater via internal gills…in their rectum! (Aren’t dragonflies fascinating?!)
When the young dragonflies have reached their final larval stage, they will climb out of the water, typically at night, onto a piece of vegetation sticking out of the water. Their exoskeleton will split down the back, and the dragonfly will slowly emerge. Birds, frogs and spiders make easy meals out of out of helpless dragonflies during this vulnerable time when it’s body is soft and its wings have not yet dried.
One particular summer day several years ago, my husband brought in several gallons of pond water and poured them into the aquarium in the living room so that he could observe pond life, including dragonfly larvae, moving about within the water. A few days later, I woke up to find no dragonfly larvae in the aquarium, several exoskeletons along the upper rim of the aquarium and winged pandemonium happening in the living room!
This summer, when we take our family trips around the states, my son and I will be keeping our eyes peeled for dragons. Because the twelve-spotted skimmer can be found in all of the lower 48 states, as well as southern Canada, it’s a sure-fire bet that I’ll be seeing more of my favorite dragons than he will. But I’ll keep my eyes open for his dragons too, just in case.