Archive for January, 2014

Black and Yellow Argiope spiders

January 31, 2014

The following photographs show two Black and Yellow Argiope spiders (Argiope aurantia) spotted during during photowalks through Huntley Meadows Park on 22 October 2013 and 04 September 2013.

Look closely at Photo 2 (of 2) in the following set of images. Notice the spider is “mummifying” its prey. Experts say spiders wrap their prey in silk in order to store food for later consumption.

22 October 2013. Photo 1.

22 October 2013. Photo 1.

22 October 2013. Photo 2.

22 October 2013. Photo 2.

The zig-zag pattern in the center of the spiderweb is a distinctive field marker for orb weaver spiders, as shown in the following photo.

Some species of orb weaver spiders decorate their webs. These web decorations are called stabilimenta. There have been many suggestions as to why spiders decorate their webs including added stability, visibility, or the opposite camouflage, to attract prey, excess silk or to attract mates. Recent research has indicated that stability & visibility, so that the web does not become damaged, may be the primary reason. Source Credit: Kim Phillips, Small Wonders.

Black and Yellow Argiope spider

04 September 2013.

Thanks to the following members of the BugGuide group on Facebook for their interesting comments about the feeding habits of spiders: Wildman Wayne Fidler; Cassie Novak; Jace Porter; and Harald Nowak.

Copyright © 2014 Walter Sanford. All rights reserved.

Mocha Emerald dragonflies (in flight)

January 29, 2014

The preceding gallery shows Mocha Emerald dragonflies (Somatochlora linearis) spotted on 25 July 2012 flying along an intermittent stream running through the “Wildlife Sanctuary,” one of seven small parks owned and maintained by the Community Association of Hollin Hills, Fairfax County, Virginia USA.

The adult flight period for Mocha Emerald dragonflies seems to be approximately one month for this location, centered on mid-July.

Mature Mocha Emerald dragonflies have emerald green eyes, as their name suggests — don’t be fooled by the play of light from the camera flash off the 30,000 facets in each of the dragonfly’s compound eyes! Speaking of the play of light, the “sparkling bokeh” background was caused by out-of-focus points of light reflected from the water surface about one- to two feet below the dragonflies.

Copyright © 2014 Walter Sanford. All rights reserved.

Mocha Emerald dragonflies (males)

January 27, 2014

The following gallery shows Mocha Emerald dragonflies (Somatochlora linearis) spotted on 25 July 2012 perching along an intermittent stream running through the “Wildlife Sanctuary,” one of seven small parks owned and maintained by the Community Association of Hollin Hills, Fairfax County, Virginia USA. These individuals are males, as indicated by their terminal appendages.

Mocha Emerald dragonflies seem to prefer shady spots, unlike most odonates, so be sure to bring a flash-equipped camera when you go hunting Mochas. And be sure to wear your Bug Shirt and Pants — mosquitos like shady spots too!

Copyright © 2014 Walter Sanford. All rights reserved.

Five steps to the next level of dragonfly spotting

January 25, 2014

Step 1. Be aware the same species of dragonfly may appear differently depending upon gender, age, and natural variation. Some species display sexual dimorphism; in contrast, both genders look virtually identical for some species. Finally, females of some species display polymorphism (also known as polychromatism).

The following slideshows/photo galleries show several species of dragonflies that may be spotted at Huntley Meadows Park easily, near the beginning of “dragonfly season.” Remember that every photo in each set shows a single species; notice the appearance of individual specimens varies considerably. All photos were taken at Huntley Meadows Park unless labeled otherwise (see information in brackets to the right of some hyperlinks to photo sources).

A. Common Whitetail dragonflies (Plathemis lydia)

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B. Great Blue Skimmer dragonflies (Libellula vibrans)

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C. Spangled Skimmer dragonflies (Libellula cyanea)

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Beware of look-alikes!

Some dragonflies look very similar to other dragonflies of a different species/gender. Here are a couple of look-alikes you’re likely to see at Huntley Meadows Park.

A. Common Whitetail versus Twelve-spotted Skimmer

B. Great Blue Skimmer versus Slaty Skimmer

Photo Sources:

Step 2. Learn to identify male-versus-female terminal appendages.

All male dragonflies have three terminal appendages, collectively called “claspers,” that are used to grab and hold female dragonflies during mating: an upper pair of cerci (“superior appendages”) and a lower unpaired epiproct (“inferior appendage”). Female dragonflies have a pair of cerci (superior appendages) that have little or no function.

Photo sources:

Related Resource: Odonate Terminal Appendages

Step 3. Spend time in the field, literally. Take time to look carefully. Search fields near water (sometimes far from water) where you may find immature- and female dragonflies. BEWARE of chiggers and ticks!

Step 4. Useful references

Use the following resources to know the species of odonates you’re likely to see at a specific location and when to look for a specific species.

A. Species lists

B. Identification Guides

Step 5. Dragonhunter’s Credo: Shoot first (photos, that is); ask questions later. (Repeat it like a mantra.)

  • Get a shot, any shot; refine the shot gradually. Good shots for easier identification: top view (including pterostigmata near wing tips); side view; face; terminal appendages.
  • Post known- and unknown specimens on Project Noah: Dragonflies and Damselflies of Huntley Meadows Park.
  • Follow a few well-known dragonhunters (virtually, that is) in order to see what they’re seeing.

Related Resources:

Editor’s Note: On Saturday, 25 January 2014, I had the honor of co-presenting a program called “Flying Dragons” with Kevin Munroe, Park Manager, Huntley Meadows Park. Kevin invited me to talk about how to make the transition from a beginner- to intermediate/advanced-intermediate dragon hunter. I prepared this photoblog post related to my part of the program, called “Five steps to the next level of dragonfly spotting.”

Copyright © 2013-2014 Walter Sanford. All rights reserved.

Lessons learned: How to use a superzoom camera to shoot insect photos

January 25, 2014

Part 1: Camera settings, using my Panasonic Lumix DMC-FZ150 superzoom camera (superseded by Panasonic Lumix DMC-FZ200 superzoom camera) and Canon 580EX Speedlite external flash unit

  • In-camera settings: RAW+JPEG; ISO/Limit Set (100/400); White Balance (Auto); AF Mode (1-area-focusing); Metering Mode (Spot); “Forced flash ON”
  • Shutter Priority AE Mode: Use a fast shutter speed, equal to or greater than the reciprocal of lens focal length (actual focal length for full-frame sensor cameras or 35mm equivalent for crop sensor cameras), in my case, usually no less than 1/800 s for a 600mm equivalent telephoto lens.
  • Use either built-in flash or external flash unit for fill flash: “… the real secret of wildlife photography is fill flash. Fill flash is one of the key techniques for easily improving wildlife images. Electronic flash improves the color balance of the image, improves color saturation, fills in dark shadows with detail, adds a catch light to an animal’s eye, and may help increase sharpness.” Source Credit: Wildlife Fill Flash. Note: Burst Mode cannot be used with flash.
  • Exposure compensation: -1 or more stops, as necessary. In Shutter Priority mode with a fixed ISO, EV adjusts aperture; minus-EV decreases aperture by one- or more stops (f-stop number gets larger), resulting in greater depth of field.

Part 2: Image post-processing using Apple Aperture – “recipe” for typical workflow (Make adjustments in order listed; use values shown in the following screen captures as a starting point.)

  • [Basic adjustments] Crop and Straighten, as necessary; White Balance (Auto); Exposure (Auto); Curves (Auto RGB); Highlights & Shadows (adjust as necessary); Exposure/Recovery (see screen captures, shown below)
  • [Add “secret sauce”] Enhance: Contrast; Definition (enhances mid-tones)
  • [Add finishing touches] Noise Reduction; Sharpen (Radius 1.5); Vignette

The following gallery shows screen captures of Apple Aperture: typical “Adjustments” are shown in the left sidebar; after/before images are shown in the “Viewer” (larger window pane).

Copyright © 2014 Walter Sanford. All rights reserved.

Blue-faced Meadowhawk dragonflies (males)

January 23, 2014

The following galleries show seven of nine male Blue-faced Meadowhawk dragonflies (Sympetrum ambiguum) spotted during a photowalk through Huntley Meadows Park on 01 October 2013.

Editor’s Note: This is Part 6 in a six-part series of posts featuring Blue-faced Meadowhawks, one of my favorite dragonflies.

Copyright © 2014 Walter Sanford. All rights reserved.

Blue-faced Meadowhawk dragonfly (male) 2

January 21, 2014

The following gallery shows a Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum). This individual is a male, as indicated by its coloration and terminal appendages.

This specimen was the second of three male Blue-faced Meadowhawk dragonflies spotted during a photowalk through Huntley Meadows Park on 08 October 2013.

Editor’s Note: This is Part 5 in a six-part series of posts featuring Blue-faced Meadowhawks, one of my favorite dragonflies.

Copyright © 2014 Walter Sanford. All rights reserved.

Blue-faced Meadowhawk dragonfly (female, red morph), redux

January 19, 2014

The following gallery shows another andromorphic Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum). This individual was spotted along the boardwalk during a photowalk through Huntley Meadows Park on 08 October 2013.

Some dragonflies, like this one, are very cooperative models. I was able to shoot over a dozen sets of photos of this female in a variety of poses. I am especially fond of shots in which the dragonfly strikes an unusual pose, such as the photo shown below.

Blue-faced Meadowhawk dragonfly (female)

Editor’s Note: This is Part 4 in a six-part series of posts featuring Blue-faced Meadowhawks, one of my favorite dragonflies.

Copyright © 2014 Walter Sanford. All rights reserved.

Blue-faced Meadowhawk dragonfly (female, red morph)

January 17, 2014

Blue-faced Meadowhawk dragonfly (female)

Andromorphic Blue-faced Meadowhawk dragonflies (Sympetrum ambiguum), like the female shown above, are less common than heteromorphs. Andromorphs have a red abdomen with black rings, like male Blue-faced Meadowhawks; unlike males, most female faces are tan and their terminal appendages look different than male appendages.

This individual was spotted along the boardwalk during a photowalk through Huntley Meadows Park on 18 September 2013; it is the same female featured in “Eye injury,” posted on 15 October 2013.

Strong backlighting by the Sun made it challenging to shoot properly exposed photographs. The following gallery features a few “arty” shots that are less technically perfect than the single image, shown above, where the Sun was to the left of my camera and the subject.

Editor’s Note: This is Part 3 in a six-part series of posts featuring Blue-faced Meadowhawks, one of my favorite dragonflies.

Copyright © 2014 Walter Sanford. All rights reserved.

Blue-faced Meadowhawk dragonfly (female, tan morph), redux

January 15, 2014

I spotted another heteromorphic Blue-faced Meadowhawk dragonfly (Sympetrum ambiguum) during a photowalk at Huntley Meadows Park on 01 October 2013. I shot lots of photos of the dragonfly as it perched in several nearby locations along the boardwalk that goes through the central wetland area.

The following gallery features several of my favorite photos of the female.

The next gallery shows my second favorite set of shots of the dragonfly. I like the look of the female’s eyes in the ambient light.

The remaining galleries, shown below, feature the same individual perching in several different poses.

Editor’s Note: This is Part 2 in a six-part series of posts featuring Blue-faced Meadowhawks, one of my favorite dragonflies.

Copyright © 2014 Walter Sanford. All rights reserved.


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