Swamp Darner dragonfly (female, oviposition)

The cavalcade of spring species of odonates continues: a first-of-season Swamp Darner dragonfly (Epiaeschna heros) was spotted on 25 April 2016 near a vernal pool at a remote location in Huntley Meadows Park.

This individual is a female, laying eggs (oviposition) in soft wood. All female damselflies and many female dragonflies, especially Aeschnidae, have an ovipositor that is used to puncture aquatic plants, logs, wet mud, etc.; eggs are placed singly in the puncture. The ovipositor is clearly visible in the following annotated image.

(See a full-size version of the original photo, without annotation.)

Related Resource: Swamp Darner Ovipositing in Rotting Log (NJ, USA), an excellent YouTube video (2:03) published on June 5, 2014, shot from the edge of a vernal pool located in New Jersey.

Copyright © 2016 Walter Sanford. All rights reserved.

New discoveries in 2015

As the story is told, a reporter asked Willie Sutton “Why do you rob banks?” “Because that’s where the money is,” Willie answered. So when people ask me why I go to the remote locations in Huntley Meadows Park, I answer “Because that’s where the undiscovered species of odonates are.”

There are undiscovered species of odonates at the remote places in the park, in part, because fewer people go to the more difficult to reach locations. Also, the remote locations are often where the “habitat specialists” are found, in contrast with the “habitat generalists” that inhabit the central wetland area.

Springtime Darner dragonfly

Teamwork, and some take-aways

18 April 2015 | Photograph used with permission from Michael Powell.

Southern Spreadwing damselfly

A Southern Fortnight, Part 1 – Year-long mystery solved!

03 MAY 2015 | HMP | Southern Spreadwing (mating pair, in tandem)

Roseate Skimmer dragonfly

Roseate Skimmer dragonfly (male)

23 SEP 2015 | Huntley Meadows Park | Roseate Skimmer (male)

Sweetflag Spreadwing damselfly

Another new species of spreadwing damselfly?

15 OCT 2015 | HMP | Sweetflag Spreadwing (male)

Copyright © 2015 Walter Sanford. All rights reserved.

Recognition received in 2015

It’s the time of year for reflection upon the past year. This is part one in a three-part series: part two will highlight New discoveries in 2015; part three will showcase my Top 10 Photos of 2015.

Several of my photographs received special recognition during 2015.

• Chesapeake Explorer – National Park Service Web portal for exploring the Chesapeake Bay region
• Vernal Pools are Wet and Dry – signage facilitating informal science education at a new park in the Town of DeWitt, New York
• Argia, Vol. 27, Issue 4, “Parting Shots,” p. 31

The December 2015 issue of Argia, The News Journal of the Dragonfly Society of the Americas, features one of my photographs of a Roseate Skimmer dragonfly (Orthemis ferruginea) that I discovered on 23 September 2015 at Huntley Meadows Park. Roseate Skimmer is extremely uncommon in Virginia: there are only three other confirmed records of this species in the state. See Roseate Skimmer dragonfly (male) for more information and photos of this handsome dragonfly.

December 2015 | Argia | Roseate Skimmer (male)

Tech Tip: Apple “Preview” was used to extract one page from the December 2015 issue of “Argia.”

Sidebar: “Argia” is a genus of damselfly, commonly known as “dancers.” For example, Variable/Violet Dancer (Argia fumipennis) is commonly found along streams in Northern Virginia.

Copyright © 2015 Walter Sanford. All rights reserved.

The first and last dragonflies of 2015

Common Whitetail dragonflies (Plathemis lydia) are like the type of party guests who are always among the first to arrive and last to leave. They are one of the first dragonfly species to appear in spring, and one of the last to disappear in fall.

24 APR 2015 | Huntley Meadows Park | Common Whitetail (female)

This post features photos of the first and last Common Whitetail dragonflies spotted during photowalks in two remote locations at Huntley Meadows Park. Both individuals are female, as indicated by their coloration, pattern of wing spots, and terminal appendages.

15 OCT 2015 | Huntley Meadows Park | Common Whitetail (female)

As its common name suggests Common Whitetail dragonflies are seen commonly, seemingly everywhere, including places far from water. Some dragonflies are habitat specialists; Common Whitetails are habitat generalists. It’s easy to look at something so common and overlook their subtle beauty, that is, until they disappear at the end of dragonfly season.

Don’t it always seem to go that you don’t know what you’ve got ’til it’s gone. Source Credit: Big Yellow Taxi, by Joni Mitchell.

Editor’s Notes: For the record, the first dragonfly of 2015 was spotted on 18 April, when Mike Powell and I co-discovered the first Springtime Darner (Basiaeschna janata) ever seen/photographed at Huntley Meadows Park! Autumn Meadowhawk dragonfly (Sympetrum vicinum) is the last dragonfly species spotted in 2015: 11 November is my personal late-date for this species in 2015; several other odonate enthusiasts have seen Autumn Meadowhawks at Huntley Meadows long afterward.

Copyright © 2015 Walter Sanford. All rights reserved.

Fatal injuries?

After several years of dragonfly hunting, I’ve seen two dragonflies with three wings rather than four: in one case, I can only speculate how the injury occurred; in the other case, I witnessed the injury firsthand.

Can dragonflies survive with three wings? The answer is yes and no: if they can fly, they can survive; if they can’t fly, they can’t survive.

If they can’t fly, they’ll starve because they only eat prey they catch while flying. Source Credit: 14 Fun Facts About Dragonflies, by Sarah Zielinski, Smithsonian.com.

On the same day I discovered a male Roseate Skimmer dragonfly (Orthemis ferruginea) at Huntley Meadows Park, I heard a loud splash in a pool of water behind me. I turned around quickly and noticed a dragonfly struggling to free itself from the surface of the water. After a few seconds, the dragonfly escaped from the water and flew briefly before landing on the ground near the place where I was standing. I was able to shoot four photos before the dragonlfy flew away.

Turns out that individual was an old, injured female Great Blue Skimmer dragonfly (Libellula vibrans). One of her wings was broken near its base; I don’t know how the injury occurred. She was able to fly, but flight was labored at best.

23 SEP 2015 | HMP | Great Blue Skimmer (old female, injured)

Two years earlier, I was photographing dragonflies along the boardwalk in the central wetland area. One male Great Blue Skimmer dragonfly in particular caught my attention: he repeatedly engaged one or more Common Green Darner dragonflies (Anax junius) in brief aerial dogfights. I vividly remember thinking, “Dude, you must have a death wish — those darners can be vicious predators!” Almost immediately afterward, a darner sheared off one of the male Great Blue Skimmer’s wings just like a buzzsaw and looped around for the kill shot. The skimmer dove for cover in vegetation overhanging the boardwalk (shown below) and his life was spared. I shot one poor-quality photo of the injured male Great Blue Skimmer; he flew away when I tried to move closer.

04 SEP 2013 | HMP | Great Blue Skimmer (male, injured)

Did the female Great Blue Skimmer meet the same fate as the male? Who knows? I know there were lots of Common Green Darners hawking invisible airborne insects over a meadow near the location where I spotted the injured female. And I know Common Green Darners feed voraciously in order to store energy for migration. Perhaps both skimmers were attacked as a potential food source.

Copyright © 2015 Walter Sanford. All rights reserved.

Full Circle

A mating pair of Common Green Darners (Anax junius) was spotted at a bioswale near the head-end of the Hike-Bike Trail at Huntley Meadows Park (HMP).

The bioswale was designed to filter the runoff which comes from the parking lot, removing heavy metals, salt, sand, etc. from the runoff before conveyance to Dogue Creek. It is supposed to slowly filter the rain water in 48-72 hours, to clean and purify the water before entering the creek. Source Credit: David M. Lawlor, Natural Resource Manager, HMP.

The pair is in tandem (a form of guarding behavior): the male (upper-right) guides the female (lower-left) to places where she can lay eggs in vegetation (endophytic oviposition).

05 AUG 2015 | HMP | Common Green Darner (mating pair, in tandem)

Did you notice the odonate exuvia located on the same reed as the Common Green Darners? Although it’s usually impossible to identify an exuvia from a photograph like the one shown above, I consulted the experts of the Northeast Odonata Facebook group.

I can’t identify the exuvia to species, but I’m pretty confident about the family — Libellulidae, a skimmer. Possibly Blue Dasher, but I’m mostly guessing there. Source Credit: Christopher E. Hill, Associate Professor, Department of Biology, Coastal Carolina University.

05 AUG 2015 | HMP | Common Green Darner (mating pair, in tandem)

Eggs may hatch after a few days, or embryonic development may take a month or more. In some species, the eggs overwinter and hatch the following spring. Each egg hatches into a very tiny prolarva that looks like a primitive insect form, quite different from the larva that will succeed it. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Locations 407-409). Princeton University Press. Kindle Edition.

As odonate larvae grow and outgrow their skin, they molt, on average 12 times. The duration of this stage of life can vary from a month to several years, depending upon both species and climate. The last molt, called “emergence,” is the metamorphosis from larva to adult; the “cast skin” that is left behind is an exuvia (pl. exuviae).

The juxtaposition of the exuvia and mating pair in the first photo is a metaphor for the circle of life, come full circle: eggs; prolarvae; larvae; emergence/adult males and females; mating pairs; males guide females to egg-laying sites.

Related Resources:

• Common Green Darner dragonflies (Part 1)
• Common Green Darner dragonflies (Part 2)
• Odonate Exuviae, by Walter Sanford

Copyright © 2015 Walter Sanford. All rights reserved.

Swamp Darner dragonfly (female)

Dragonflies are classified as either “fliers” or “perchers,” based upon their feeding habits. Swamp Darner dragonflies (Epiaeschna heros) are fliers; it is uncommon to see them perching.

15 MAY 2015 | Huntley Meadows Park | Swamp Darner (female)

This individual is a female, as indicated by her terminal appendages. She was perching near a vernal pool, probably resting after egg-laying (oviposition).

15 MAY 2015 | Huntley Meadows Park | Swamp Darner (female)

Please look at the full-size version of both photos in order to see the exquisite coloration of this dragonfly.

Related Resources: Digital Dragonflies, presenting high-resolution digital scans of living dragonflies.

• Genus Epiaeschna | Epiaeschna heros | Swamp Darner | female | top view
• Genus Epiaeschna | Epiaeschna heros | Swamp Darner | female | side view
• Genus Epiaeschna | Epiaeschna heros | Swamp Darner | male | top view
• Genus Epiaeschna | Epiaeschna heros | Swamp Darner | male | side view

Copyright © 2015 Walter Sanford. All rights reserved.

Post update: Malformed odonates

All odonates, that is dragonflies and damselflies, have four wings. The following Common Green Darner dragonfly (Anax junius) has a malformed wing: one of its two hind wings didn’t expand to full-size during emergence.

28 APR 2015 | HMP | Common Green Darner (male, malformed wing)

This individual is a male, as indicated by its coloration and terminal appendages. The terminal appendages are shown more clearly in the next photo than the preceding one.

28 APR 2015 | HMP | Common Green Darner (male, malformed wing)

I’ve seen this guy two times during recent visits to a vernal pool at Huntley Meadows Park (HMP). I call him “3.75,” in reference to the number of wings he has. Like other Common Green Darners, “3.75” is able to fly and hawk smaller flying insects; he stops to rest more frequently than other darners, perhaps because he has to work harder to fly than he would if he had four fully-formed wings.

A lot can go wrong when a dragonfly metamorphoses from a larva to an adult. I’m surprised more odonates aren’t malformed, although the ones with fatal flaws probably tend to be uncommon sightings.

Related Resources:

• Malformed odonates, by Walter Sanford
• The Life Cycle of a Dragonfly, British Dragonfly Society
• Odonate Nymphs, by Steve Krotzer, Haysop Hill Photography [larvae are also known as nymphs]
• Odonate Emergence, by Giff Beaton
• Dragonfly metamorphosis going wrong (#423), a YouTube video by nature1upclose

Copyright © 2015 Walter Sanford. All rights reserved.

Common Green Darner dragonflies (Part 2)

While resting on my Coleman camp stool at a vernal pool in the forest at Huntley Meadows Park (HMP), I noticed a large UFO moving across the meadow. Unidentified Flying Odonate, that is. I followed the “oh” to the location where it landed; turns out the “object” was a mating pair of Common Green Darner dragonflies (Anax junius) “in wheel.” Either they didn’t like that place or I spooked them, and they flew to another nearby location. When I followed them to that spot, the same thing happened. That’s when I lost visual contact. I don’t have to tell you I was feeling very frustrated! Fortunately, I spotted the mating pair again as I was walking toward my camp stool.

This time I followed my mantra of wildlife photography: Get a shot, any shot; refine the shot gradually. I shot a few photos “from a galaxy far, far away” and gradually crept closer and closer to the subjects. The photographs featured in Part 1 were taken at this location.

Eventually the dragonflies moved to a fourth location where I was able to take two snaps of the mating pair perched deep in the grass before they moved on again.

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

I shot the rest of the photos at the dragonflies’ final stop, where they were perched at eye level on a fallen tree alongside the vernal pool.

The following photograph is one of my all-time favorites. In particular, I like the way the rich colors of the dragonflies are complemented by the muted colors in the background. Notice also that the terminal appendages (cerci) of the female are clearly visible (below the male’s thorax), and the male’s epiproct (one of three claspers) is shown clearly at the top of the female’s head. The first version is a square crop.

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

An unconstrained crop was used to create another version of the same photo. I prefer to crop photos using either the original aspect ratio of the camera (3 x 4) or a square format because it’s easier to print photos in commonly-used formats. Nonetheless, I just couldn’t make the 3 x 4 format work for this photo. I like the composition of the unconstrained version slightly more than the square version. Which version do you think looks better?

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

The next two photos were taken from slightly different viewpoints.

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

Tech Tips: In order to take tack-sharp handheld wildlife photographs, I prefer to shoot in shutter priority mode at relatively fast shutter speeds, and I always use an external flash unit. For more information, see “Lessons learned: How to use a superzoom camera to shoot insect photos.”

When a subject is especially cooperative, I will shoot a few photos in aperture priority mode. Although f/8 is the minimum f/stop (and maximum depth of field) for my Panasonic Lumix DMC-FZ150 superzoom camera, I prefer to shoot at f/7.1 because some photography experts say the focus is slightly soft at f/8.

The last photo was shot in aperture priority using the following settings: ISO 125; 46mm (253mm, 35mm equivalent); -1 ev; f/7.1; 1/60s; flash fired in manual mode. Everything being equal, I think all of the preceding images — shot in shutter priority mode — look slightly sharper than this photo. What do you think?

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

Copyright © 2015 Walter Sanford. All rights reserved.

Common Green Darner dragonflies (Part 1)

The following mating pair of Common Green Darner dragonflies (Anax junius) was spotted at a vernal pool in the forest at Huntley Meadows Park (HMP). The pair is “in wheel“: the male is on top; the female is on the bottom.

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

This is the first mating pair of Common Green Darners I have photographed in wheel. Turns out I’ve been looking for love in all the wrong places.

Copulating pairs fly away from water. Source Credit: Paulson, Dennis (2011-12-19). Dragonflies and Damselflies of the East (Princeton Field Guides) (Kindle Location 4775). Princeton University Press. Kindle Edition.

After copulation, Common Green Darners usually oviposit in tandem on open water.

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

Some species of dragonflies hook-up briefly, with copulation lasting only a few seconds. In contrast, this mating pair was in wheel for about 30 minutes. I followed the couple to five different resting places; Part 2 of this mini-series will feature photos from another location.

28 APR 2015 | HMP | Common Green Darner (mating pair, in wheel)

Common Green Darner is one of at least five major species of dragonflies known to be migratory in North America. See interactive three-dimensional (3-D) virtual imagery of the five migratory dragonflies, including Common Green Darner, provided by the Migratory Dragonfly Partnership.

Related Resources: Digital Dragonflies, presenting high-resolution digital scans of living dragonflies.

• Genus Anax | Anax junius | Common Green Darner | female | top view
• Genus Anax | Anax junius | Common Green Darner | female | side view
• Genus Anax | Anax junius | Common Green Darner | male | top view
• Genus Anax | Anax junius | Common Green Darner | female | side view

Copyright © 2015 Walter Sanford. All rights reserved.