I am betting that most of you who have been in the Nebraska outdoors this summer have seen at least one dragonfly. Usually they are found near water, but not necessarily so, sometimes adult dragonflies can venture a long way from water. However, dragonflies are definitely aquatic insects. In fact dragonflies spend most of their lives in the water! Adult dragonflies mate and then the females deposits eggs on the surface of the water. Those eggs hatch into larval dragonflies that may spend months, even years living in the water. Once the larvae mature they crawl out of the water, and change into the adult form. Unlike some other aquatic insects like mayflies, adult dragonflies do feed and survive for some time, but no more than a few weeks. During their short summer as an adult, they again find a mate and the females deposit eggs starting the life cycle over again. I found this short video that demonstrates that whole dragonfly life cycle.
I believe most folks realize that adult dragonflies are predators that prey on other insects including mosquitoes. They are masters of aerial combat and capture most of their prey on the wing. However, underneath the water, I am betting that most folks do not realize that larval dragonflies are also predators. Larval dragonflies eat a variety of prey including at times, small fish! However, fish more often turn the table on larval dragonflies, sometimes even adult dragonflies. In some of our Nebraska waters there can be an incredible amount of larval dragonflies and they are an important prey for many species of fish. I have seen panfish caught from Nebraska’s sandhill lakes that were absolutely packed full of larval dragonflies even during the dead of winter!
Waterbodies that have relatively clean water and an abundance of aquatic vegetation tend to have more aquatic insects like larval dragonflies. Fish that feed on aquatic insects may cruise through aquatic vegetation stalks picking off those “bugs”. I love waters that have clean water and an abundance of aquatic vegetation (They Ain’t “Weeds”), those are much more productive fisheries.
OK, all of this is interesting to a pointy-headed fisheries biologist or aquatic ecologist. So what? At heart I am just an old fisherman; an old fisherman who learned a long time ago that the more one knows about fish and the waters in which they live, the more fish that will be caught. And besides that, it is just interesting to think about whenever a dragonfly whizzes by, and it gives us a greater appreciation for the wild environments around us and the critters that live in them. Get outdoors this weekend and appreciate it even more!