Posts Tagged ‘Huntley Meadows Park’

Autumn Meadowhawk is a fall species

November 11, 2019

Autumn Meadowhawk (Sympetrum vicinum) is classified as a fall species of odonate. This blog post features two of many Autumn Meadowhawks that were spotted during a photowalk along the boardwalk in the central wetland area at Huntley Meadows Park, Fairfax County, Virginia USA.

The first individual is a male, as indicated by his terminal appendages. He is perched on a Swamp Rose (Rosa palustris) leaf. Nothing says “fall” like this little red devil against a background of fiery foliage!

The last individual is a male, perched on a cattail (Typha sp.) leaf near Swamp Rose and buttonbush (Cephalanthus sp.). The brown globes are the fruit of buttonbush.

The Backstory

My collection of field notes includes two text files that list lots of photos of both Blue-faced Meadowhawk (S. ambiguum) and Autumn Meadowhawk dragonflies that were never published in my photoblog.

Copyright © 2019 Walter Sanford. All rights reserved.

Blue-faced Meadowhawk (young male)

November 8, 2019

A Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum) was spotted near a vernal pool in the forest at Huntley Meadows Park, Fairfax County, Virginia USA.

This individual is a young male, as indicated by the red pruinescence that partially covers his yellow-orange and black abdomen, plus his terminal appendages.

20 SEP 2013 | HMP | Blue-faced Meadowhawk (young male)

Regular readers of my photoblog know I’m fond of head-tilts in which the dragonfly seems to display some of its personality, especially when the individual is looking at me (below).

20 SEP 2013 | HMP | Blue-faced Meadowhawk (young male)

Left, right, left. I followed this guy from perch to perch for several minutes.

20 SEP 2013 | HMP | Blue-faced Meadowhawk (young male)

The Backstory

My collection of field notes includes two text files that list lots of photos of both Blue-faced Meadowhawk and Autumn Meadowhawk dragonflies (S. vicinum) that were never published in my photoblog. Most of the photos were taken during Fall 2013 when one of many vernal pools at Huntley Meadows Park was near peak diversity for odonate species that inhabited the pool. Sadly, those days are long gone!

Copyright © 2019 Walter Sanford. All rights reserved.

Detente

October 30, 2019

Two Autumn Meadowhawk dragonflies (Sympetrum vicinum) were spotted perched side-by-side on the boardwalk in the central wetland area at Huntley Meadows Park (HMP), Fairfax County, Virginia USA. Both individuals are males, as indicated by their coloration and terminal appendages.

15 NOV 2013 | HMP | Autumn Meadowhawk (males)

Male dragonflies of the same species are natural rivals, competing for the attention of females that are willing to mate. Like many, if not most other species of dragonflies, male Autumn Meadowhawk dragonflies stake out a “territory” near prime spots for females to lay eggs (oviposition); unlike many, if not most other species, male Autumn Meadowhawks don’t seem to defend their territory aggressively.

15 NOV 2013 | HMP | Autumn Meadowhawk (males)

Notice the male shown on the upper-left is using his front legs like windshield wipers to clean his eyes and face. Hey, he wants to look well-groomed for the ladies!

Related Resources

The Backstory

My collection of field notes includes two text files that list lots of photos of both Blue-faced Meadowhawk and Autumn Meadowhawk dragonflies (S. vicinum) that were never published in my photoblog. Most of the photos were taken during Fall 2013 when one of many vernal pools at Huntley Meadows Park was near peak diversity for odonate species that inhabited the pool. Sadly, those days are long gone!

Copyright © 2019 Walter Sanford. All rights reserved.

Data mining for Autumn Meadowhawk

October 28, 2019

This is a follow-on to my last blog post, Are adult Autumn Meadowhawks arboreal?

Data mining can be used to recognize patterns in official records of field observations by many amateur and professional odonate hunters, confirmed by experienced vetters.

Let’s begin by looking at the adult flight period for Autumn Meadowhawk (Sympetrum vicinum), the target species for a proposed field study during 2020 at the Vermont Institute of Natural Science.

Adult Flight Period

According to records for the Commonwealth of Virginia maintained by Dr. Steve Roble, Staff Zoologist at the Virginia Department of Conservation and Recreation, Division of Natural Heritage, the adult flight period for Autumn Meadowhawk (S. vicinum) is from May 28 to January 03. The species is classified as “common.” Its habitat is “ponds.”

Bear in mind, Dr. Roble’s records are for the entire state, therefore the adult flight period for S. vicinum seems to be longer than it is in reality. The adult flight period for a single site is probably shorter. For example, according to records for Northern Virginia maintained by Kevin Munroe, former manager of Huntley Meadows Park, the adult flight period for Autumn Meadowhawk is June 13 to December 10 (seen most September to October).

DSA Odonata Central Records

What is shown by a deep-dive into the Dragonfly Society of the Americas Odonata Central records database for Autumn Meadowhawk in the Commonwealth of Virginia?

There are currently 38 confirmed records for S. vicinum in Virginia, as shown by the following distribution map.

Source Credit: Abbott, J.C. 2006-2019. OdonataCentral: An online resource for the distribution and identification of Odonata. Available at http://www.odonatacentral.org. (Accessed: October 27, 2019).

Key: blue dots = Dot Map Project; green dots = Accepted records; yellow dots = Pending records.

Analysis

There are 14 records for teneral/immature adult Autumn Meadowhawk, ranging from 30 May to 19 August: May (1); June (5); July (5); August (3). Notice that the greatest cluster of records for teneral/immature adults occurs in June and July. There are a few records for mature adults toward the end of this time period and no records for mating pairs.

There are 24 records for mature adult Autumn Meadowhawk, ranging from 07 August to 03 January: August (2); September (5); October (13); November (1); December (2); January (1). Only a few records for teneral/immature adults occur at the beginning of this time period. The greatest cluster of records for mature adults occurs in October. Seven (7) of the records throughout the time period are for mating pairs, beginning in September; the greatest cluster of records for mating pairs also occurs in October.

What are the take-aways?

38 records is an admittedly small sample size. In the opinion of the author, patterns in the data are muddied by analyzing data for the entire state rather than a single location. There is almost certainly a south-to-north pattern in dates of emergence, mating, and disappearance for any given species, as well as atypical patterns resulting from micro-climates that exist throughout the state.

All of that being said, the data in the DSA Odonata Central records database for Virginia is consistent with my first-hand observations in Northern Virginia showing that Autumn Meadowhawk emerges in mid- to late-June, disappears for two- to three months, and returns to the ground/water when it’s time to mate during fall.

One big question remains to be answered: Where do adult Autumn Meadowhawks go when they disappear soon after emergence — do they live in the forest canopy? One thing we know is certain: There are few if any official records for mature adult Autumn Meadowhawk on the ground during mid- to late-summer. Food for thought.

Related Resource: Are adult Autumn Meadowhawks arboreal?

Copyright © 2019 Walter Sanford. All rights reserved.

Are adult Autumn Meadowhawks arboreal?

October 25, 2019

Autumn Meadowhawk (Sympetrum vicinum) is classified as a fall species of odonate. In the mid-Atlantic United States, meadowhawks seem to disappear for several months after they emerge during early to mid-summer and reappear during fall. Where do they go? No one knows for sure. I speculate Autumn Meadowhawk is an arboreal species of dragonfly that returns to the ground/water when it’s time to mate.

Emergence

The first individual — photographed soon after emergence — is a/an teneral/immature male, as indicated by the tenuous appearance of his wings, coloration, and terminal appendages.

24 JUN 2016 | HMP | Autumn Meadowhawk (teneral/immature male)

The next individual is a/an teneral/immature female, as indicated by the tenuous appearance of her wings, coloration, and terminal appendages.

24 JUN 2016 | HMP | Autumn Meadowhawk (teneral/immature female)

Time to mate

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

15 NOV 2013 | HMP | Autumn Meadowhawk (mating pair, “in wheel”)

This mating pair is “in wheel”: the male is on the upper-left; the female is on the lower-right. 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.

Forest Canopy Walk at Vermont Institute of Natural Science

Observing dragonflies at the Earth’s surface is fairly easy; observing dragonflies at the treetops, not so much. The new Forest Canopy Walk at the Vermont Institute of Natural Science (VINS) should facilitate the latter.

During 2020, I hope to collaborate with Kelly Stettner, Black River Action Team (BRAT), and Anna Morris, Lead Environmental Educator, VINS, to gather evidence that supports my speculation that adult meadowhawk dragonflies are arboreal. Field observations will be collected on the ground and along the Forest Canopy Walk.

Hosted by Anna Morris, Kelly Stettner and her family scouted the VINS site on 05 October 2019, including the new Forest Canopy Walk and nearby water bodies that provide suitable habitat for Autumn Meadowhawk. Special thanks to Anna for providing a behind the scenes tour a week before the official opening of the Forest Canopy Walk.

Gallery photos used with permission from Kelly Stettner, BRAT.

A week later, Autumn Meadowhawk was observed along the Forest Canopy Walk for the first time. The following photos provide circumstantial evidence that we might be on the right track. I love it when a plan comes together!

Gallery photos used with permission from Anna Morris, VINS.

I’m happy to share that during our public Forest Canopy Walk opening today [12 October 2019], I was stationed at the Eagle platform and got to see two (2) meadowhawks zooming around, then perched on the railing (pictures attached)! This is about 60 feet up, near a Sugar Maple and a Red Oak. [More meadowhawks were seen] the next day at nearly 90 feet up! At this height and as it was so sunny there were at least four individuals zooming around, landing on visitors, etc. Source Credit: Anna Morris, Lead Environmental Educator, VINS.

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

Left on the cutting room floor

April 15, 2019

Close readers of my blog may have noticed I’ve posted a lot of photos recently that were taken years ago. Why were the photos passed over for publication closer to the time the shots were taken?

Sometimes there are better shots from the same photowalk that I’m eager to share, and sometimes they just don’t make the grade. The former requires no explanation; the following photos help to illustrate the latter.

The following female Slender Spreadwing damselfly (Lestes rectangularis) was spotted during a photowalk around a vernal pool in the forest at Huntley Meadows Park. The damselfly was perched in a hidey-hole in the vegetation at angle that made it impossible to get the entire subject in focus from head-to-tail.

The first photo shows the head and thorax in focus, but the tip of the abdomen and terminal appendages are out of focus.

15 SEP 2016 | HMP | Slender Spreadwing (female)

The last photo shows the tip of the abdomen and terminal appendages in focus, but the head and thorax are in soft focus. Look closely at a full-size version of the photo and you can see both styli (sing. stylus), structures that serve as sensors (like “curb feelers“) in egg positioning during oviposition.

15 SEP 2016 | HMP | Slender Spreadwing (female)

The odd thing is the focus point is nearly the same in both photos, and the aperture is identical. Go figure! Anyway, less than ideal focus is something that will cause me to reject photos every time. And then there’s that “too hot” blade of grass in the lower-right corner — talk about distracting!

Copyright © 2019 Walter Sanford. All rights reserved.

So close, yet so far!

April 10, 2019

Two Common Whitetail dragonflies (Plathemis lydia) were spotted perched on a wooden fence rail located near the terminus of the Hike-Bike Trail at Huntley Meadows Park (HMP), Fairfax County, Virginia USA.

The individual shown on the left is a mature female; the one on the right is a mature male.

15 SEP 2016 | HMP | Common Whitetail (mature female and male)

Sexing Common Whitetail dragonflies

For many of the common species of odonates found in Northern Virginia, I created a collection of annotated guides that illustrates how to differentiate gender by looking at terminal appendages. The difference in the pattern of wings spots for male and female Common Whitetails is sufficient to identify gender.

Life Cycle of Odonates

Odonates (dragonflies and damselflies) are aquatic insects that spend most of their life as larvae that live in water; this stage of their life cycle can last from a few months to a few years, depending upon the species. 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 wonder how these two mature adults were able to be so close yet resist the compelling biological urge to hook up!

Copyright © 2019 Walter Sanford. All rights reserved.

Smeared Dagger Moth caterpillar

April 8, 2019

A Smeared Dagger Moth caterpillar (Acronicta oblinita), a type of stinging caterpillar, was spotted on 15 September 2016 during a photowalk along the boardwalk that goes through the central wetland area at Huntley Meadows Park (HMP).

Stinging caterpillars use poison-filled bristles to defend themselves from predators. If you touch a stinging caterpillar, you’ll know it by the burning, itching… Source Credit: 13 Stinging Caterpillars. [Smeared Dagger is No. 10.]

Thanks to Mike Powell, fellow wildlife photographer and blogger, for identifying this unusual caterpillar way back when both of us were less experienced amateur naturalists.

Copyright © 2019 Walter Sanford. All rights reserved.

Time series: Purple Milkweed (Parts 3, 4)

March 18, 2019

Purple Milkweed (Asclepias purpurascens) flowers were photographed on 06 and 10 June 2016 near a large vernal pool at Huntley Meadows Park in Fairfax County, Virginia USA.

Kevin Munroe, former park manager at Huntley Meadows, designated Purple Milkweed as a “plant of interest” due to the fact that it is officially a rare plant species in the state of Virginia (S2).

Part 3

These plants are covered with ants, lots of ants!

Later, a single Great Spangled Fritillary butterfly (Speyeria cybele) was feeding on the same milkweed plant, along with lots of ants.

Part 4

Lots of Great Spangled Fritillary butterflies (Speyeria cybele) were observed feeding on the milkweed. The next two photos show the same individual in two poses.

The proboscis, a specialized structure that enables butterflies to siphon liquids from flowers, is shown clearly in the next two photos.

An Eastern Tiger Swallowtail butterfly (Papilio glaucus) was feeding on another cluster of milkweed flowers. Eastern Tiger Swallowtail is the State Insect of Virginia. Really, who knew there are official state insects?

The last photo is my favorite in both galleries.

Related Resources

Copyright © 2019 Walter Sanford. All rights reserved.

Time series: Purple Milkweed (Part 2)

March 15, 2019

The following Purple Milkweed (Asclepias purpurascens) flower was photographed on 01 June 2016 near a large vernal pool at Huntley Meadows Park in Fairfax County, Virginia USA.

The milkweed is covered by a cornucopia of insects including ants (one ant can be seen in the full-size version of the first photo), what I think is some type of weevil (the darker insects featuring a curved proboscis that reminds me of an elephant trunk), a cool looking metallic gold-green bee, and what I think is a species of Crane Fly.

As it turns out, my tentative identification of the Crane Fly is incorrect.

The crane fly is actually a [species of] Stilt Bug [from the Family Berytidae]. I can tell by the clubbed antennae and distally enlarged femora. Source Credit: Natalie Hernandez, member of the BugGuide Facebook group.

The gold-green bee is shown more clearly in the full-size version of the following photo. Masumi Palhof, another member of the BugGuide Facebook group, thinks the bee might be a Silky Striped-Sweat bee (Agapostemon sericeus).

Related Resources

Post Update

The weevil is in the subfamily Baridinae (commonly known as “flower weevils”), maybe Odontocorynus umbellae or O. salebrosus. Source Credit: Ted C. MacRae, Senior Entomologist & Science Fellow. Beetles In The Bush [blog].

Copyright © 2019 Walter Sanford. All rights reserved.


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