Dragonflies of Banshee Reeks Nature Preserve and Vicinity
Marc Sagan
DRAGONFLIES ARE INTERESTING !
Walk up to any pond on a clear warm day and you'll probably see dragonflies darting along the shoreline and perched on plants at the water's edge. You won't see them on rainy, windy or cold days because they're less active then.
Each one seems to patrol its beat or territory, back and forth along the same route, usually perching at the same spots, often returning to the same twig. You'll seldom see them catch anything but they devour insects, small and large, and they chase other dragonflies from their territories.
You might see one flying a foot or so above another as she repeatedly dips her abdomen into the water, laying eggs. Some males grasp females behind the head, flying in tandem.
Some dragonflies have colors as brilliant as butterflies but their flight is much speedier and they can hover and fly backwards as well as hummingbirds. Keeping a flying dragonfly in the field of your binoculars is a challenge because they change directions so quickly.
In the water dragonfly eggs hatch into amazing little killers which eat other insects such as mosquito larvae and almost anything else they can catch. They live in the water for periods ranging from a few months to several years, growing and replacing their skins or shells from 8 to 17 times. When they are mature they crawl out of the water on plants, stones or wood and shed one last time, emerging as winged dragonflies. They hide in vegetation while their wings are pumped up to full size and where soft parts of their bodies harden. Within a few days or a week they're ready to fly, hunt , breed,and lay eggs for the next generation. Most adults live for only two to four weeks but some species live for a few months, even migrating in the fall.
Damselflies, closely related to dragonflies are generally smaller and less speedy, catching slow-moving insects such as aphids. Dragonfly wings at rest stay extended like airplane wings, but damselflies fold their wings over their backs.
There are about 5000 species of dragonflies worldwide but only about 400 in North America. You can learn to recognize most of the common ones at Banshee Reeks, about twelve species, within one or two summers. To start learning get a copy of Stokes Beginner's Guide To Dragonflies from a local bookstore or Amazon.com. Binoculars are a great help. Spot a dragonfly noticing its size, color and patterns and find its picture in the book. Read a bit about recognizing males, females and immatures, and in the process, you'll start noticing their behavior. They're fascinating. You might even sign up for a brief introductory session on dragonflies at Banshee Reeks.
As a poet has said of learning botany, "It helps to train and spur the brain, unless you haven't gotany."
The Common Whitetail is usually the most common dragonfly in this area. The male's tail (abdomen) is pale blue at first with angled white marks along the outer edges of each abdominal segment. As he ages the abdomen turns whiter so the marks don't show up.
The Whitetail female is brown and has the same angled marks on her abdomen but they are pale yellow and easier to see than those of the male.
The Twelve-spotted Skimmer is a large black, white and gray dragonfly, quite handsome. I find it quicker to notice three black marks on each wing than to count to twelve. The female is similar to the female Whitetail, but look at the pictures in your book to see the difference in their abdomens.
The Widow Skimmer is the other very common dragonfly with large black marks on its wings. I remember its name by associating the words, "black marks, black widow, widow skimmer". The Whitetail's black stripes are at midwing while the Widow Skimmer's are at the wing bases near the abdomen. The female Widow Skimmer's abdominal marks are rectangular, like dominos, not angled.
At Banshee Reeks there are two medium -sized dragonflies with black-tipped blue abdomens. The Blue Dasher usually has pale amber areas on its wings.
The Eastern Pondhawk doesn't and it has white abdominal appendages which are easy to see.
There's no mistaking the Eastern Amberwing because it is small, only 0.9" long, with amber wings having red stigmas. Females have amber spotted wings.
In midsummer you may see the Calico Pennant, small and with brown-spotted clear wings and a red triangle on the top of each abdominal segment. Quite striking !
The Halloween Pennant, also small, has amber (orangey..think pumpkin) wings with brown spots, and no red triangles on its abdomen.
The Slaty Skimmer, quite common all summer has clear wings and dark blue, almost black, body. Females and immature males are brown with whitish stripes on thorax and abdomen.
And here are two Slaty Skimmers in the 'Wheel Position'.
One of the most widespread and largest dragonflies in North America is the Green Darner, 3" long. The male's blue abdomen is prominent as is the female's green thorax. Both have a bull's-eye pattern on the forehead but that is hard to see because you'll seldom see one perching. They're great fliers. The picture is one I made from a specimen which had just collided with a car.