Odonates (dragonflies and damselflies) are aquatic insects that spend most of their life as larvae (nymphs) that live in water; this stage of their life cycle can last from a few months to a few years. Finally, they emerge from the water and metamorphose into adults in order to reproduce; their offspring return to the water and the cycle begins again.
I think it’s safe to say less is known about odonates during the aquatic phase of their lives than during the terrestrial phase. In my opinion, there is a real opportunity to make a significant contribution to the body of scientific knowledge about odonates by collecting and identifying exuviae.
What can be learned from collecting odonate exuviae?
Here are two examples that illustrate why I think it’s important to collect and identify odonate exuviae.
I’ve never seen an adult Arrow Clubtail dragonfly (Stylurus spiniceps). That’s not surprising, since many experienced odonate hunters classify them as uncommon to rare.
But I know a place along the Potomac River in Fairfax County, Virginia USA where I am certain Arrow Clubtail dragonflies live. How do I know? Because I collected a Stylurus spiniceps exuvia from that location on 04 August 2016.
More recently, my good friend and odonate hunting buddy Mike Boatwright discovered a small breeding population of Zebra Clubtail dragonflies (Stylurus scudderi) at an undisclosed location in Amherst County, Virginia USA. For several years, Mike found exuviae but no adults. On 22 July 2021, years of searching the site finally came to fruition when Mike discovered a teneral female Zebra Clubtail.
Do you need a permit in order to collect odonate exuviae?
A strict interpretation of the Code of Virginia might lead one to think a permit is required.
It is unlawful to collect animal parts, such as feathers, claws, and bones without a permit (4 VAC 15-30-10 and §§ 29.1-521 and 29.1-553). Source Credit: Overview: Collecting, Exhibiting, and Releasing Wildlife, Virginia Department of Wildlife Resources.
That being said, it appears there is an exception for Phylum Arthropoda.
At this time no DWR permit is required for the following: Phylum Arthropoda EXCEPT for the Superfamilies Astacoidea & Parastacoidea (Crayfish) – Arthropoda includes: Insects, arachnids, millipedes, centipedes and other crustaceans (EXCEPT Crayfish) such as: isopods, amphipods etc. … Source Credit: Overview: Collecting, Exhibiting, and Releasing Wildlife, Virginia Department of Wildlife Resources.
I interpret the Code of Virginia to mean a permit IS NOT required to collect odonate exuviae.
How to collect odonate exuviae
Before you collect an exuvia, please photograph the specimen in situ. Record the date, location, and species (if known). A photograph is especially valuable when both the adult and exuvia are shown in the same photograph.
17 JUN 2021 | PNC. Wm. County | Anax junius exuvia (lateral)
Here are my tips for collecting exuviae. Bear in mind, I’m a perfectionist. It’s a fault, but hey, I am what I am and that’s all that I am.
I carry several items in my camera bag: a small plastic spoon; narrow strips of heavy card stock (maybe 3/8″ wide and two inches long); a small pair of scissors (one of three tools in a simple Swiss Army knife); and small plastic containers.
“Go kit” for collecting odonate exuviae.
I’m guessing most people just grab an exuvia with their fingers, but whenever I do that I hear a crunching sound that makes me cringe and parts tend to break off, e.g., legs.
If the exuvia is on a sandy stream bank, then I scoop the specimen with a spoon. If the specimen is clinging to something like a rock or wooden dock, then I slide the handle of the spoon under the body and gently pry it off the surface. Those little grabbers on the end of their legs are very “grippy,” so “gently” is the operative word. If the handle of the spoon won’t fit under the body, that’s when I use the card stock.
If the exuvia is clinging to vegetation, e.g., a cattail, then make the “peace sign” with one hand and insert the stem up to the notch between your pointer- and middle fingers and then close those fingers. Put your hand BELOW the exuvia, palm up, like a cup (in case the specimen falls off the stem). Use scissors to cut the stem below your fingers/hand and a little above the exuvia. Put the specimen in a collecting container, including the stem.
I use large plastic pill bottles. (I take eye vitamins that come in a wide-mouth bottle, perfect for big specimens with long legs such as cruisers and Dragonhunter.) I also use the smallish plastic containers for Philadelphia cream cheese — they can be “nested,” allowing you to carry several containers without taking up much space.
There, now you know more about how to collect odonate exuviae than you ever wanted to know!
What are the take-aways?
Hey, I get it — building a collection of odonate exuviae and learning to identify them might not interest you. But I can assure you there are many people like me who are interested in odonate exuviae who would love to have specimens that you find and collect.
I’m not necessarily saying you should go out hunting specifically for exuviae, but I am saying when you go hunting adult dragonflies and damselflies please be on the lookout for exuviae and collect them when you find them (and I predict you will).
In this way, there is a multiplier effect that will result in the collection of more specimens than a single individual is likely to find. In turn, this should help to advance our understanding of the odonates of Virginia.
Copyright © 2022 Walter Sanford. All rights reserved.