Archive for November, 2016

When things go wrong

November 30, 2016

One week after I witnessed the miraculous metamorphosis of an emergent male Common Sanddragon dragonfly (Progomphis obscuris), I was reminded that a lot can go wrong during emergence. Like the old blues standard says…

When things go wrong, go wrong with you
It hurts me too.

An emergent nymph was spotted during a photowalk along Dogue Creek at Wickford Park. The nymph was in the same position hours later, so I’m sad to say the dragonfly was stuck in its exuvia.

Related Resource: Common Sanddragon dragonfly (emergent male), a blog post by Walter Sanford featuring a time-series of photographs documenting the metamorphosis of an emergent male Common Sanddragon dragonfly on 01 June 2016 at Wickford Park.

Copyright © 2016 Walter Sanford. All rights reserved.

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Common Sanddragon dragonfly (male)

November 28, 2016

A Common Sanddragon dragonfly (Progomphus obscurus) was spotted during a photowalk along Dogue Creek at Wickford Park, Fairfax County, Virginia USA. This individual is a male, as indicated by his coloration and terminal appendages.

Like all male clubtail dragonflies, the hindwings of male Common Sanddragons are “indented” near the body. This distinctive field marker is shown well by the first, fourth, and last photos in this gallery.

Half of the photographs in this set are full-frame, that is, uncropped. Like the next photo. Knee-high rubber boots enabled me to photowalk the stream channel, allowing me to get much closer to the subject. This guy is the second of at least five adult males I was able to photograph at close range during the outing.

Some people imagine the yellow markings along the abdomen look like small burning candles.

Copyright © 2016 Walter Sanford. All rights reserved.

New late-date for Familiar Bluet

November 26, 2016
A Familiar Bluet damselfly (Enallagma civile) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a male.

18 NOV 2016 | Huntley Meadows Park | Familiar Bluet (male)

A Familiar Bluet damselfly (Enallagma civile) was spotted near a vernal pool located in Huntley Meadows Park. This individual is a male, as indicated by his black and blue coloration and by his terminal appendages.

A Familiar Bluet damselfly (Enallagma civile) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This individual is a male.

18 NOV 2016 | Huntley Meadows Park | Familiar Bluet (male)

18 November is a new personal late-date for Familiar Bluet at Huntley Meadows Park. As it turns out, another male Familiar Bluet was spotted by Michael Powell on the same date at another location in the park. The record late-date for Familiar Bluet in the Commonwealth of Virginia is 27 December, set in 2015.

Copyright © 2016 Walter Sanford. All rights reserved.

Wildlife watching “Wildlife Watching” sign

November 24, 2016

There is a “Wildlife Watching” sign located along the boardwalk at Huntley Meadows Park, near the observation tower overlooking the central wetland area.

Notice the Autumn Meadowhawk dragonfly (Sympetrum vicinum) perching on the signage. This individual is a male, as indicated by the bright red coloration of his abdomen and by his terminal appendages.

Regular readers of my photoblog know I love a good head-tilt! Doesn’t this guy look jaunty?

Autumn Meadowhawks like to rest on sunlit surfaces like the sign (and boardwalk) in order to absorb thermal energy.

Hey folks, you’re looking the wrong way — there’s a big dragonfly behind you!

The hemi-marsh at Huntley Meadows Park is a good habitat for many species of odonates, including Autumn Meadowhawk.

I spent about 30 minutes watching the sign, waiting for the dragonfly to land at different places on the sign. During that time, several people passed the sign but no one noticed the dragonfly. As the sign says, “Take time to look carefully” when you visit a wildlife watching park.

Editor’s Note: On the traditional day when we give thanks for our many blessings, I am especially thankful for the opportunity to be a frequent and careful observer of the natural beauty of the hemi-marsh at Huntley Meadows Park, and for many good friends with whom I share the experience. Happy Thanksgiving!

Copyright © 2016 Walter Sanford. All rights reserved.

Variable Dancer (mating pair, “in heart”)

November 23, 2016

A mating pair of Variable Dancer damselflies (Argia fumipennis violacea) was spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR). This pair is “in heart“: the male is on the upper-left; the female on the lower-right.

A mating pair of Variable Dancer damselflies (Argia fumipennis violacea) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This pair is "in heart."

14 JUN 2016 | JMAWR | Variable Dancer (mating pair, “in heart“)

In the following photo, the male is on top; the female on the bottom.

A mating pair of Variable Dancer damselflies (Argia fumipennis violacea) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This pair is "in heart."

14 JUN 2016 | JMAWR | Variable Dancer (mating pair, “in heart“)

The taxonomic classification of Variable Dancer is as follows: Order Odonata (Dragonflies and Damselflies); Suborder Zygoptera (Damselflies); Family Coenagrionidae (Narrow-winged Damselflies); Genus Argia (Dancers); Subspecies Argia fumipennis violacea (Violet Dancer).

Variable Dancer is a habitat generalist that can be found almost anywhere there is water. Mature males are easy to recognize due to their unique coloration — there are no other species of violet damselflies found in the eastern one-third of the United States. Female Variable Dancers, like many female odonates, are more challenging to identify than males.

It’s helpful to get shots of mating pairs of damselflies, especially “in tandem,” since males and females of the same species can look quite different. The excellent high-resolution digital scans by Gayle and Jeanelle Strickland, listed under “Related Resources” (below), provide clear views of male and female Variable Dancer damselflies.

Related Resources: High-resolution digital scans created by Gayle and Jeanelle Strickland.

Copyright © 2016 Walter Sanford. All rights reserved.

Blue-fronted Dancer

November 21, 2016
A Blue-fronted Dancer damselfly (Argia apicalis) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

14 JUN 2016 | JMAWR | Blue-fronted Dancer (male)

These two photos show one of many Blue-fronted Dancer damselflies (Argia apicalis) spotted during a photowalk around Mulligan Pond, Jackson Miles Abbott Wetland Refuge (JMAWR). This individual is a male, as indicated by his coloration and terminal appendages.

A Blue-fronted Dancer damselfly (Argia apicalis) spotted at Mulligan Pond, Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is a male.

14 JUN 2016 | JMAWR | Blue-fronted Dancer (male)

The taxonomic classification of Blue-fronted Dancer is as follows: Order Odonata (Dragonflies and Damselflies); Suborder Zygoptera (Damselflies); Family Coenagrionidae (Narrow-winged Damselflies); Genus Argia (Dancers); Species apicalis.

Related Resources: High-resolution digital scans created by Gayle and Jeanelle Strickland.

Copyright © 2016 Walter Sanford. All rights reserved.

Southern Spreadwing at MNWP

November 19, 2016

Many Southern Spreadwing damselflies (Lestes australis) were observed around the stormwater management pond located at Mason Neck West Park (MNWP) during Fall 2016. The following gallery, presented in chronological order, showcases select specimens spotted during several photowalks at the park.

The first individual is a female, as indicated by her coloration and terminal appendages.

A Southern Spreadwing damselfly (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This individual is a female.

27 SEP 2016 | MNWP | Southern Spreadwing (female)

The next two photos show a couple of males, as indicated by their coloration and terminal appendages.

A Southern Spreadwing damselfly (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This individual is a male.

27 SEP 2016 | MNWP | Southern Spreadwing (male)

A Southern Spreadwing damselfly (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This individual is a male.

27 SEP 2016 | MNWP | Southern Spreadwing (male)

The following photo shows a mating pair “in tandem,” the post-copulatory phase when the male guides the female to egg-laying sites. The male is on top; the female on the bottom.

A mating pair of Southern Spreadwing damselflies (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This pair is in tandem.

27 SEP 2016 | MNWP | Southern Spreadwing (mating pair, in tandem)

The female uses her ovipositor to insert eggs into vegetation (endophytic oviposition).

A mating pair of Southern Spreadwing damselflies (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This pair is in tandem; the female is laying eggs (oviposition).

27 SEP 2016 | MNWP | Southern Spreadwing (mating pair, in tandem)

More males were spotted on consecutive days in early-October.

A Southern Spreadwing damselfly (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This individual is a male.

03 OCT 2016 | MNWP | Southern Spreadwing (male)

A Southern Spreadwing damselfly (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This individual is a male.

04 OCT 2016 | MNWP | Southern Spreadwing (male)

The last individual is a female that I found resting/roosting in a field of grasses, quite a distance from the water. As it turns out, this female — spotted on 14 October 2016 — is also the last Southern Spreadwing observed at Mason Neck West Park during 2016. It’s worth noting the late-date for Southern Spreadwing at MNWP is consistent with the late-date of 15 October 2015 for the same species at Huntley Meadows Park.

A Southern Spreadwing damselfly (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This individual is a female.

14 OCT 2016 | MNWP | Southern Spreadwing (female)

A Southern Spreadwing damselfly (Lestes australis) spotted at Mason Neck West Park, Fairfax County, Virginia USA. This individual is a female.

14 OCT 2016 | MNWP | Southern Spreadwing (female)

Copyright © 2016 Walter Sanford. All rights reserved.

Voltinism

November 17, 2016

Voltinism is a term used in biology to indicate the number of broods or generations of an organism in a year. Source Credit: Wikipedia.

Some species of odonates, such as Southern Spreadwing damselfly (Lestes australis), can be multivoltine.

Since the first official record of Southern Spreadwing damselfly at Huntley Meadows Park — a male spotted on 23 May 2014 in a drainage ditch near a vernal pool in the forest — the author has carefully monitored this location for the past two years. Henceforth, this location shall be referred to as the “study site.”

Field observations have shown one brood of Southern Spreadwing during Spring 2014 and Spring 2015; an individual from another probable brood of Southern Spreadwing was spotted during Fall 2015. Individuals from two broods of Southern Spreadwing were observed during Spring and Fall 2016.

Males

The following photo shows the only Southern Spreadwing observed at the study site during Spring 2016. This individual is a male, as indicated by his coloration and terminal appendages.

There are two vernal pools at the study site: the larger one is more like a small permanent pond that was formerly fishless; the smaller one is a true vernal pool and appears to be fishless. This individual was observed in a drainage ditch near the true vernal pool: the ditch is wet during spring/early-summer; dry in late-summer/fall.

Territorial Expansion

There is another vernal pool at Huntley Meadows Park that the naturalists refer to as the “Accidental Vernal Pool” because it was created by accident during the construction phase of the wetland restoration project. As it turns out, this pool is a good habitat for many species of odonates, including some species that prefer fishless water.

A male Southern Spreadwing was spotted at the “accidental vernal pool” on 26 May 2016; this is the first time this species has been observed in that location. It’s good to see the expansion of Southern Spreadwing territory, especially since it appears the habitat at the “study site” has been degraded by the introduction of fish to the larger pond.

One or more males were spotted the following day at the accidental vernal pool.

Female

A single Southern Spreadwing was observed at the study site during Fall 2016.

This individual is a female, as indicated by her coloration and terminal appendages.

I thought I had discovered a male Sweetflag Spreadwing damselfly (Lestes forcipatus) on 15 October 2015 at the study site. I made my speculative identification before I knew that Southern Spreadwings can be multivoltine. The observation and positive identification of a female Southern Spreadwing during the same month (in consecutive years) at the same location almost certainly means the species of the male I saw in 2015 was misidentified.

Editor’s Notes: Southern Spreadwing damselflies have been observed at two other locations in Northern Virginia: males from a single brood were observed during Spring 2016 at Meadowood Recreation Area; males and females from a single brood were observed during Fall 2016 at Mason Neck West Park. Further field observations are necessary to determine whether Southern Spreadwing is multivoltine at these sites.

Related Resource: Southern Spreadwing at MNWP, by Walter Sanford.

Copyright © 2016 Walter Sanford. All rights reserved.

Post update

November 15, 2016

The first official record of Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum) at Jackson Miles Abbott Wetland Refuge was observed at Mulligan Pond on 15 September 2016. 10 days later, another Blue-faced Meadowhawk was spotted near the same location.

A female Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum) spotted at Jackson Miles Abbott Wetland Refuge, Fairfax County, Virginia USA. This individual is an heteromorph.

25 SEP 2016 | JMAWR | Blue-faced Meadowhawk (female heteromorph)

This individual is a female heteromorph, as indicated by her tan coloration and terminal appendages.

As it turns out, the female spotted on the 15th and this one spotted on the 25th were the only Blue-faced Meadowhawks seen during many photowalks around Mulligan Pond during Fall 2016.

Copyright © 2016 Walter Sanford. All rights reserved.

Time to mate

November 13, 2016

In a recent blog post, I wrote…

Both Blue-faced Meadowhawks and Autumn Meadowhawks are classified as fall species of odonates. In the mid-Atlantic United States, meadowhawks seem to disappear for several months after they emerge during early summer and reappear during fall. Where do they go? No one knows for sure. I speculate Blue-faced Meadowhawks and Autumn Meadowhawks are arboreal species of dragonflies that return to the ground/water when it’s time to mateSource Credit: More previews of coming attractions.

Fall is the time to mate for Autumn Meadowhawk dragonflies (Sympetrum vicinum), as you can see in the following photo.

A mating pair of Autumn Meadowhawk dragonflies (Sympetrum vicinum) spotted at Huntley Meadows Park, Fairfax County, Virginia USA. This pair is "in wheel."

06 NOV 2016 | HMP | Autumn Meadowhawk (mating pair, “in wheel“)

This mating pair is “in wheel.” All dragonflies and damselflies have a 10-segmented abdomen, numbered from front to back: male dragonfly secondary genitalia, called hamules, are located in segments two and three (S2 and S3); female genitalia in segment eight (S8). Dragonflies form the mating wheel in order for their genitalia to connect during copulation.

Odonates (dragonflies and damselflies) are aquatic insects. Most of their life is spent underwater as a nymph. The life span of a nymph depends upon the species: it’s a few months for some species; a few years for other species. Individual adult odonates — like the ones we see flying around Huntley Meadows Park (HMP) — usually live one- to two months, although many different individuals from the same species may be seen for longer periods of time. Adult odonates have one goal: mate in order to reproduce. When fertilized eggs are laid in water, the circle of life comes full circle: eggs; prolarvae; larvae; emergence/adult males and females; mating pairs; males guide females to egg-laying sites (some species, such as Autumn Meadowhawk) or solo females lay eggs (all other species).

Copyright © 2016 Walter Sanford. All rights reserved.


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