The newly formed Prairie Oaks chapter of the Master Naturalists carries on the traditions of service and stewardship of land and nature begun 20 years ago when the organization was founded. For those interested, bird counts, bio-blitzes (really!), upkeep of civic amenities such as pollination and butterfly gardens, or even the study and conservation of small things such as the topic of today’s column—the dragonfly. One dragonfly, ‘Francis’, which became the logo of the Texas Master Naturalists, has a local back story.
Over 20 years ago a colleague and I were in the middle of a local pond with a seine attempting to determine what sorts of creatures were living in the water. A small piece of flotsam floated past, an odd looking bit of bark, that turned out to have a dragonfly nymph attached to it.
Everyone knows that dragonflies like water, but not everyone knows that the biggest reason is that their immature stage or nymph is aquatic. We were curious about this aquatic stage, so we took the bark and its hitchhiker back to the lab and installed it in an aquarium for observation. While the nymph was a voracious feeder, it was growing slowly enough that we thought we should name it. So, Francis (a gender-neutral name), grew for about two and a half years and greeted us one morning by flying around the laboratory. He (for he turned out to be a male) was determined to be a Cyrano darner because the front of the face is inflated like a large nose (like Cyrano de Bergerac). You can see an exemplar of the species at https://bit.ly/2K1hh8h .
Two and one half years as a nymph! In contrast, once released as an adult, Francis probably flew for only about 40 days if he avoided predators. We are used to thinking in terms of the immature stages of vertebrates that are relatively short compared to the adult stages. It can be the opposite in invertebrates where the larval and nymphal stages are of long duration compared to the lifespan of adults. Cyrano darners are unusual in Texas in the amount of time they require to develop into adults, but are hardly alone. The dreaded pecan weevil spends two years in the soil before emerging. Many mayflies are often a year old before becoming adults, where they spend only a day flying about and breeding before succumbing to their biology and dying. Once released, Francis flew for about 40 days if he avoided predators.
The choice of the dragonfly for Texas Master Naturalists was intentional: the qualities of detailed beauty, wide ecosystem importance, and its representation of renewal as we can see from the fascinating story of nymphal development detailed in Francis’ story here. For more about the dragonfly as Texas Master Naturalist symbol go here: http://txmn.org/wp-content/blogs.dir/55/files/2010/03/TexasStar2011-10TXEcoSystems.pdf
When next you see a dragonfly remember: It all starts with the small.
Dr. Forrest Mitchell is the Prairie Oaks advisor, professor and research project leader, Texas A&M University AgriLife Research.