A solitary dragonfly is an indicator animal. That means that his presence or absence tells us something about the quality of our environment. When dragonflies are plentiful, we know that nearby ponds are healthy. In order to provide a home for breeding dragonflies, the water must be clean, with growing plants, which in turn provides the oxygen needed for all the aquatic creatures from water bugs to frogs and turtles. Ancient people, who were finely tuned to the environment, were well aware of this relationship. One example would be Navajo culture, where dragonflies symbolized pure water.
In their larval stage, as nymphs, they live entirely in water. Usually freshwater ponds, or wetlands, but also in slow moving streams or small lakes. The larval stage can last from a few months to more than a year. During that stage of their lives, nymphs can molt as many as fifteen times.
Eventually they emerge from the submerged life and climb the stem of an aquatic plant where they undergo their final molt. When the last skin has been shed, they have fully formed wings, and after the wings have dried, they are ready to fly. Unlike butterflies, there is no pupae, they go directly from the larva to adult. In their adult form, dragonflies usually only live for a few months.
Dragonfly nymphs feed on small aquatic insects, a favorite food being mosquito larva. So Dragonflies are a great way to control mosquito populations. As adults, dragonflies also eat flying termites, flies, and gnats. If you’re a southern boy like me, anything that eats gnats is a good thing.
One of the really cool things about dragonflies is that they can helicopter. Alone among nature’s flying creatures, they can fly backward, or side to side, as well as straight up or down. They can also hover for as long as a minute. Totally mobile in the air. They’re quite fast as well. There is solid evidence that they can reach speeds of 30mph, there are some reports of certain species going nearly twice that speed. That makes them fascinating to watch, and just about impossible to photograph in flight. You have to catch one at rest, and sneak up on it. That last part is not easy since they have 360 degree vision. A very cautious approach, dark clothes and no sudden moves will get the shot.
Another aspect that’s always fascinating to me is that dragonflies are in that group of creatures that still resemble their ancient origins. Like crocodiles, sharks, and the nautilus, today’s dragonflies are remarkably similar to their ancestors going back more than 100 million years.
Dragonflies reached their peak size during the Carboniferous Period, 350 to 280 million years ago. It’s an interesting period in earth’s history. The middle part of that era was remarkably similar to present day conditions, especially regarding atmospheric CO2 levels and temperatures. It was much cooler than the geologic eras before and after. Oxygen levels were higher, which allowed some insects to become giants. Some of those prehistoric dragonflies were the size of seagulls or hawks.
That just makes them all the more interesting, both from the standpoint of understanding their role in our ecology, and as subjects to photograph. It’s like capturing a glimpse of the world hundreds of millions of years past.