Dragons and Damsels Around Your Pond and Water Garden

The air show surrounding me was mesmerizing while monitoring vernal pools with a team of Master Watershed Stewards at Gifford Pinchot State Park. Jeweled performers darted and danced while hunting on the wing. This exquisite troupe of expert aerial acrobats was comprised of dazzling dragonflies and damselflies dashing above the pools in the stately forest. At times, our heads and arms became temporary perching posts. It was magnificent! These insect marvels have been around for millions of years, are important components of aquatic ecosystems, and are indicators of good water quality.

Dragonflies and damselflies both belong to the insect order Odonata. There are 6,500 species of odonates worldwide, with more being discovered. North America is home to over 400. They are found on every continent except Antarctica and are found almost anywhere there is freshwater, in lakes, ponds, wetlands, streams, rivers, vernal pools, and bogs. Most species prefer still water, but some are adapted to living among the cobble in faster-moving streams. They look similar in many ways, yet there are differences. Dragonflies have short, stout bodies. At rest, they hold their wings flat and spread out. Damselflies are thin and slender. At rest, damselflies hold their wings upright, together like a sail.

Both begin their life in the water and go through incomplete metamorphosis, bypassing the resting pupal stage. Adults lay eggs in water, plant tissue, rotting logs, or other material. Nymphs hatch in just a few days. This is the lengthiest life stage, lasting a few months to years, depending on the species. Nymphs live concealed below the water's surface in the mud and around vegetation. They are voracious predators. Young nymphs feed primarily on zooplankton. Larger nymphs often lie in wait and ambush anything they can catch, including tadpoles, insects, snails, small fish, and even other odonates. They have a spoon-shaped, hinged lower jaw that shoots out at lightning speed to catch prey. It's impressive! I once saw a dragonfly nymph bite the head right off another of its kind! No critter of the same or smaller size is safe from its hunt.

Nymphs hatch and molt several times before emerging as adults. The emergence is magical and happens in less than an hour. A nymph crawls out of the water and perches vertically on vegetation or nearby structures. Its exoskeleton splits open and a winged adult emerges. Within minutes, the wings and abdomen expand, and the transformation completes. They may take flight thirty minutes after emerging and are tender and delicate for 24-48 hours, making them very vulnerable prey to fish, frogs, spiders, and birds. These juveniles fly to meadows or woodlands, remaining in the safer environment for 1-2 weeks. They will find their way back to freshwater, where they will live out their remaining days. They have unique flight ability and excellent color vision, the best of the insect world, making them the perfect hunting machine. Odonates are a natural pest control, eating whatever flying insects are plentiful – flies, midges, beetles, mosquitoes, and more. They consume hundreds of insects, including pests, daily.

If you find dragonflies and damselflies captivating, you may be interested in attracting them to your backyard. A backyard pond would be appropriate habitat for both nymphs and adults. If there is a water source nearby that supports them, they will find their way to your pond. Because PA has abundant freshwater, there is probably a waterway close by. Strong fliers and those that breed in small ponds, such as green darners, wandering gliders, common whitetails, and blue dashers, will be the most likely to arrive.

Carefully plan your pond project. Construct your pond in a level area, preferably at the bottom of a slope, with the overflow directed away from your house. To attract odonates, place it where there is plenty of sun for basking and consider planting evergreens and shrubs nearby to break prevailing winds. Deciduous trees close to your pond may drop too many leaves into it, overloading it with nutrients. Larger ponds with varying water depths and high plant diversity will attract more species. Small, do-it-yourself ponds with plastic or fiberglass liners are not ideal. They may be too small, too shallow, and the sides may be too steep. Plant a diversity of submerged, emergent, and floating native plants in and around your pond. Plants provide protection, shade, oxygen, a place to lay eggs, a place to emerge, perching posts, and food and shelter for prey. Place flat stones around your pond to provide basking sites. Use sticks in the pond to create perching posts. Do not introduce predators such as frogs or ornamental fish like koi and goldfish into the pond. They will eat the odonates. Be sure to consider placing your pond where you can see and enjoy it. Lastly, check building ordinances in your municipality before beginning a pond project.

The presence, abundance, and diversity of dragonflies and damselflies are indicative of good water quality and healthy ecosystems. Species range from very sensitive to very tolerant of temperature, flow, plant diversity, habitat disturbance, excessive nutrients, and pollution. Damselfly nymphs are moderately tolerant of pollution; dragonfly nymphs are more sensitive, especially species that burrow. A diversity of odonates around any waterway is a good sign! The most important thing we can do to protect these ancient, hunting machines is to protect their habitat. They are both fascinating and ecologically important. Let's continue to protect them!