Category Archives: Insects

Tigers and Tents

Eastern tiger swallowtail in PA (photo from Wikimedia Commons)

9 May 2024

We’re more than a week into May now, so it’s likely you’ve seen the tigers and tents that first appeared in late April. If you haven’t, here’s who they are.

Tigers

I first noted tiger swallowtails at Enlow Fork on 25 April but I remember seeing one earlier in Schenley Park. When was your earliest tiger swallowtail?

Find out more about them in this vintage blog: Flying Tigers

Tents

Tentworms in Schenley Park, 25 April 2016 (photo by Kate St. John)

I saw the first tentworms on 30 April in Frick Park, but it seems this is not a big year for them. I haven’t seen many other tents. Did you know that tentworms are a favorite food of yellow-billed and black-billed cuckoos? Have you seen a cuckoo yet?

Learn more about these social insects in this vintage article: Tents

(photo by Kate St. John)

It’s time for Spray Your Clothes Day

It’s Spray Your Clothes Day (photo by Kate St. John)

11 April 2024

There’s a danger outdoors in Pennsylvania’s suburbs, parks and woods. The first step to protect yourself is to spray your clothes in early spring.

The Danger:

When a black-legged tick (Ixodes scapularis) sucks your blood it can transmit a parasite that causes Lyme disease, an illness that can ruin your life for a very long time. Black-legged ticks are especially dangerous in May and June when the tiny nymphs, only as big as a poppy seed, are questing for a blood meal.

Nymph highlighted on Chart of black-legged tick life stages (image from cdc.gov via Wikimedia Commons)

If you don’t think you’ll see a tick in Pittsburgh’s suburbs, city parks and your own garden, think again. Deer don’t carry Lyme disease but they do carry ticks — a lot of ticks — and deer are everywhere.

Deer on Forbes Ave, Squirrel Hill, 7 Nov 2023 (photo courtesy Mardi Isler)

Are there deer in your backyard? There are also ticks.

The Prevention:

By spraying your clothes with permethrin you repel ticks and lower your likelihood of a tick bite. Spray your clothes outdoors in early April on a dry windless day so the spray doesn’t touch your skin. (Read the directions on the bottle.)

Here’s all you need to know about Spray Your Clothes Day activities and how to prevent Lyme disease.

Honeybees Go Home for the Eclipse

Total solar eclipse, Berea, Ohio, 8 April 2024 (photo by Jeff Cieslak)

9 April 2024

For three minutes yesterday afternoon, people in a wide swath of the U.S. from Texas to Maine were wowed by the total solar eclipse. Jeff Cieslak was in the totality zone in Berea, Ohio and captured the photo at top. Look closely at the dark edge and you’ll see solar prominences (flares).

Map of the path of 8 April 2024 solar eclipse totality (image from NASA via Wikimedia Commons)

Pittsburgh and Dubois, PA, just east of the totality zone, were both close enough to experience a 97% eclipse. Our light level was like dusk and the temperature got cooler. Charity Kheshgi captured the partial eclipse in Pittsburgh at 3:17 to 3:20pm.

View of the 97% eclipse in Pittsburgh, 8 April 2024 at 3:19pm ET (photo by Charity Kheshgi)

Meanwhile Marianne Atkinson noticed a change in honeybee behavior at her home in Dubois, PA. She’s providing a honeybee feeder this spring, filled with sugar water, to feed hungry bees in the early days before the flowers bloom. Yesterday morning her feeder was mobbed with honeybees and was running dry.

Honeybees at the feeder, Dubois, PA, 7 April 2024 (video by Marianne Atkinson)

There were too many bees for her to safely refill the feeder so she put out a second one (white rim). It was mobbed, too.

Honeybees at two feeders in Dubois, PA, 8 April 2024 before the partial eclipse (photo by Marianne Atkinson)

And then the eclipse began. Marianne describes what happened.

I had just added a second honey bee feeder this afternoon, not long before the eclipse started. But, during the eclipse at 97%, there were very few bees on either feeder! The yellow feeder only had two bees and the gravel feeder had 3 bees. I took this opportunity to add more nectar to the yellow feeder, since it was empty.

[Meanwhile] The many American Goldfinches and Pine Siskins were chattering away in the trees nearby during the whole eclipse. The sky had gotten a little darker, but not dark like a solar eclipse in totality. There were clouds during most of the eclipse, with occasional peaks of sun or seeing it through thin clouds. I was able to view it off and on.

— email from Marianne Atkinson, Dubois, PA, 8 April 2024

Honeybees are diurnal and they return to their hive at dusk to spend the night indoors. Apparently the light level during a 97% eclipse is low enough to prompt bees to go home. After the eclipse the honeybees came back quickly to both feeders. Marianne said, “They had just recently discovered the pea gravel feeder, but did not waste any time in utilizing it!”

Did you notice any special animal or insect behavior during the eclipse? Leave a comment with your observations.

(credits are in the captions)

Hungry Bees at the Bird Feeder

Bee turns over a sunflower seed at the bird feeder, 23 Feb 2024 (photo by Marianne Atkinson)

24 February 2024

Yesterday afternoon was warm and sunny at Marianne Atkinson’s house when she noticed bees at her bird feeder and sent me this message:

I am concerned about several honey bees. It is 48° and sunny on Feb. 23, 2024 at 3:15 P.M. The bees are crawling on the sunflower chips that are in this little window feeder and on my steps and platform feeder.  The sunflower chips are dry. There is no water in them for the bees to drink or nectar.

Why are they doing this? Are they okay?

Bees at the bird feeder, 23 Feb 2024 (video by Marianne Atkinson)

Years ago I learned from beekeeper friends that early spring is a hungry time for honeybees. The warmth wakes them up in the hive, they go looking for food, but there are no flowers yet. Beekeepers provide extra food in the hive at this time of year but honeybees in the wild must go exploring.

Howard Russell at Michigan State University Extension provided this explanation:

Honey bees take advantage of any food source after a long, cold winter, including bird feeders. …

The bees collect the pollen-sized seed dust particles and yeast that are found in the cracked corn and other seeds we set out for our little feathered friends for which, I’m sure, the bees are extremely grateful. The bees will move on to their preferred food sources as spring flowers begin to appear. 

Michigan State University Extension: Hungry honey bees visiting bird feeders

This winter continues to fluctuate from cold (today) to warm (in the 60s Monday through Wednesday). Keep your feeders filled for birds … and hungry honeybees.

(photo and video from Marianne Atkinson)

Pollution Prevents Night Pollination

White-lined sphinx moth (photo from Wikimedia Commons)

15 February 2024

Plant pollination has been declining for many reasons including the absence of insects due to pesticides and habitat loss. Now a new reason has surfaced that has nothing to do with the number of flowers and bugs. Research has found that air pollution prevents nighttime pollination by turning off the scent of flowers.

The white-lined sphinx moth (Hyles lineata) is an important nighttime pollinator of purslane, primrose and rose. The research team led by J.K.Chan in eastern Washington, teased out the chemical emitted from pale evening primrose (Oenothera pallida) that attracts the hawkmoths.

Pale evening primrose, Oenothera pallida (photo from Wikimedia Commons)

The moths were particularly tuned to two different flavors of monoterpenes, a class of chemicals found in plant oils [that] evaporate quickly in the air. Moths, whose antennae are roughly as sensitive as a dog’s nose, can pick up the scent several kilometers away from a flower.

But there is an Achilles heel. When the researchers exposed the monoterpenes to NO3, it reacted with the oils, causing them to degrade by between 67% and 84%.

Anthropocene Magazine: Nighttime pollination is plummeting. Some clever sleuthing pinpointed a surprising culprit.

Air pollution doesn’t just change the scent of flowers. It erases the scent. The moths can’t find them.

Anthropocene Magazine continues, “While NO3 [a component of NOx] is less of a problem during the day because it breaks down in sunlight, it accumulates at night, when many pollinators, including the hawkmoths, are active.”

NOx causes trouble for humans, too, because it combines easily with VOCs (Volatile Organic Compounds) to create ground-level ozone (the bad ozone) and fine particulate which is inhaled so deeply into our lungs (PM2.5).

How pollution forms ground-level ozone (diagram from Wikimedia Commons)

If we reduce NOx pollution we help ourselves and plants at the same time.

(photos and diagram from Wikimedia Commons; click on the captions to see the originals)

Mopane Worms

Mopane worm caterpillars on mopane leaves (photo from Wikimedia Commons)

8 February 2024

In southern Africa, caterpillars of the emperor moth Gonimbrasia belina (or Imbrasia belina) are commonly called mopane worms because they feast on the leaves of mopane trees (Colophospermum mopane). Their final instar is shown above, adult below.

Adult form of mopane worm: the emperor moth (photo from Wikimedia Commons)

During my trip in southern Africa I did not notice the trees but their oddly shaped leaves caught my attention.

Clump of mopane trees (photo from Wikimedia Commons)

I had no idea of their significance as a place to find food.

Mopane leaves (photo from Wikimedia Commons)

Mopane worms are prized as human food. When they reach full size women and children avidly pick them from the mopane leaves, squish out their guts and take them home to boil and sun dry. When fully prepared the mopane worms look like this:

Mopane worms to eat (photo from Wikimedia Commons)

I had the opportunity to sample mopane worms at Dusty Road Township Experience, an award-winning restaurant in Victoria Falls, Zimbabwe where we ate traditional food.

What did mopane worms taste like to my naive palate? Earthy. Crispy. Very earthy.

Perhaps the flavor was so earthy because I ate the head first. In Zimbabwe this makes no difference but in Botswana they take the heads off before they eat them because the heads change the taste. I wish I’d known so I could have tried it both ways.

Learn more about mopane worms and how to cook them in this video by Emmy @emmymade. She tastes them both ways and describes their flavor at 3.5 minutes into the video.

video embedded from emmymade on YouTube

(credits are in the captions)

Tiny Blue Lights In The Woods

14 November 2023

On my way to somewhere else I found … tiny blue lights in the woods. I have never seen them in person but these photos from Anna Ruby Falls Recreation Area in the Chattahoochee National Forest are intriguing. Bioluminescent mushrooms glow green, fireflies glow yellow-green, but these are blue.

Each light is one of two ends of a fungal gnat larvae (Orfelia fultoni). This photo by Alan Cressler, embedded from Flickr, shows what the larva looks like during the day.

Orfelia fultoni, Anna Ruby Falls Recreation Area, Chattahoochee National Forest, White County, Georgia 5
Orfelia fultoni, Anna Ruby Falls Recreation Area, Chattahoochee National Forest, White County, Georgia 5 (photo embedded from Alan Cressler on Flickr)

Alan Cressler describes them:

Orfelia fultoni, Anna Ruby Falls Recreation Area, Chattahoochee National Forest, White County, Georgia:

This is the only bioluminescent fungus gnat larvae in North America. Both whitish ends of the larvae emit a blue light used to lure prey. Although they may be common in proper habits, apparently there are very few places in the southeast where they form extensive colonies. One place is Dismal Canyon in Alabama where they are locally called “dismalites”. I was invited by my friends who work for the Chattahoochee National Forest to view and photograph the extensive colony at Anna Ruby Falls Recreation Area. Locally the event is called “fox fire” and there are scheduled night hikes to witness the amazing colony. Other than the guided night hikes, after hours entry into the area is prohibited.

Fungus gnat larvae live within a slime tube and develop a network of sticky filaments that capture prey that are attracted by the blue glow. The sticky filaments can be seen in the photos.

Orfelia fultoni, Anna Ruby Falls Recreation Area description, Alan Cresler on Flickr

In the photographs above, the lights don’t look connected but you can see how they move in this video in New Zealand. The bluish glow worms in New Zealand are not the same species but they have a similar appearance and behavior.

video embedded from PBS Deep Look

Back in Georgia the foxfire glows mid-May through June when the gnat’s larval form is alive. Night hikes are offered during those months but pre-registration is required and the hikes fill up fast. Don’t wait until May 2024 to check this website for Foxfire Night Hikes at Anna Ruby Falls: https://gofindoutdoors.org/events/foxfire-night-hikes-coming-soon/

(Originals and credits of the slideshow photos can be seen by clicking on each photo)

A Wasp, An Oak, and Indelible Ink

Screenshot from Making Manuscripts: Oak Gall Ink (source video below from the British Library on YouTube)

12 November 2023

Nowadays it’s rare to write anything by hand unless it’s the size of a Post-It note. When we really want to say something we use keyboards and touch screens to generate digital text read on screens or, less often, on paper. Our writing equipment becomes obsolete so rapidly that our computers and cellphones are replaced within a decade. (Who among us is still using the same cellphone since 2013? Do we even remember what model it was?)

So consider this: Humans used the same writing tool, the same indelible ink, from the 5th to the 19th century. When applied to parchment, it is readable 1,700 years later. The ink is easy to make by hand from natural ingredients and is still used in calligraphy today. To make iron gall ink, the process starts with a wasp and an oak.

When a cynipid wasp lays an egg in a developing oak leaf bud, the hatched larva secretes a substance that makes the oak surround it with a gall. The wasp (Andricus kollari) and the oak marble gall below are from Europe but similar wasps and oak galls occur in North America(*).

The outer shell of the gall is rich in tannins whose presence protects the wasp from predation.

Oak marble gall on white oak forced by Andricus kollari (photo from Wikimedia Commons)

When crushed and soaked in water the galls’ tannins give color to the ink.

Oak marble galls on the twig, forced by Andricus kollari (photo from Wikimedia Commons)

Two more ingredients transform the ink for final use: Iron sulfate dissolved in water makes the ink black.

Iron sulfate crystals (photo from Wikimedia Commons)

Gum arabic dissolved in water makes the ink sticky enough to hold onto parchment or paper.

Gum arabic in lumps and powder (photo from Wikimedia Commons)

This video from the British Library shows how iron gall ink is made.

(video embedded from the British Library on YouTube)

Eventually we used paper instead of parchment, even for important documents, and iron gall ink fell out of favor because the acid in iron sulfate makes the paper disintegrate. To solve that problem we invented paper-friendly inks and then computers.

Iron gall ink has oxidized the cellulose, causing the paper to disintegrate (from Wikimedia Commons)

Medieval manuscript creation used natural products from animals, plants and minerals. See the process from parchment to ink to binding in this 6-minute video from the Getty Museum.

video embedded from the Getty Museum on YouTube

Read more at Making Ink From Oak Galls: Some History & Science.

(*) p.s. The amount of tannin varies by type of gall and the tree species the gall came from. Galls with the most tannin work best.

(credits are in the captions)

Trying To Get Indoors

Asian lady beetle (photo from Wikimedia Commons)

26 October 2023

Pittsburgh’s spotted lanternfly plague (Lycorma delicatula) is mostly over after recent cold weather knocked out lots of adults. It’s not a bad year for brown marmorated stink bugs, so are the insect plagues over? Not quite. Yesterday I happened into a swarm of Asian ladybeetles.

Asian lady beetles congregate to overwinter in a crack, October 2018 (photo from Wikimedia Commons)

Asian ladybeetles (Harmonia axyridis) were imported to the U.S. 35 years ago as predators for aphids, adelgids, psyllids and scales. They do a good job and they caused no trouble until they were able to overwinter starting in 1993.

Ladybeetles overwinter as adults that gather in the fall with the goal of “The More The Merrier.” Attracted to sunlight and warmth reflecting off south or southwest-facing light-colored buildings, a few accumulate and attract others by sight and smell. Pretty soon the area is crazy-busy with ladybeetles as in the photo above.

The bugs are looking for cracks in which to spend the winter. If a crack leads to a warm place indoors, that’s even better.

Asian lady beetles preparing to overwinter (photo from Wikimedia Commons)

Once inside, the warmth can keep them active.

It is not uncommon for tens of thousands of beetles to congregate in attics, ceilings and wall voids, and due to the warmth of the walls, will move around inside these voids and exit into the living areas of the home.

In addition to beetles biting (which they do), they exude a foul-smelling, yellow defensive chemical which will sometimes cause spotting on walls and other surfaces. Most people are only annoyed by the odor of these chemicals. However, some individuals have reported experiencing an allergic reaction to the defensive excretions.

Penn State Extension: Multicolored Asian Lady Beetle (Ladybug)

Penn State Extension has helpful advice on how to vacuum them (avoid getting them up into the machine!) at Multicolored Asian Lady Beetle (Ladybug).

The good news is: Have you seen a spotted lanternfly lately? Probably not! Winter is a great pest control system.

(photos from Wikimedia Commons; click on the captions to see the originals)

A Closer Look at Sleeping Bumblebees

Two bumblebees sleeping on goldenrod, Duck Hollow, 18 Sep 2023 (photo by Kate St. John)

26 September 2023

Last week at Duck Hollow I found two bumblebees asleep on goldenrod. The temperature was a little chilly but the morning was bright and sunny. Were the bees waiting to warm up in the sun?

Bumblebee sleeping on goldenrod, 18 Sep 2023 (photo by Kate St. John)

Eight weeks ago I highlighted the reason why male bees sleep on flowers in July and August. Males don’t live in a hive so they sleep outdoors. They are solitary, searching for a mate, and nearing the end of their lives.

Female bumblebees return to the hive at night if they can. In the hot months of July and August females are indoors at night. However bad weather or chilly temperatures may force them to sleep outdoors until they warm up the next morning.

So I wondered are these sleeping bumblebees male or female? I can tell with a closer look at the bees.

Female bumblebees bring food to the hive so they have pollen sacks on their hind legs. If you see a full pollen sack on a bee’s hind leg you can be sure it’s female, as shown on the right in the photo below.

Male and female bumblebees (photo by Kate St. John)

A bee without pollen, like the one on the left, is either a female who delivered her pollen and has just come back for more, or it’s a male without a pollen sack.

I can see two obvious differences between male and female in these photos.

MaleFemale
HindlegsHairySmooth convex-shaped structure for holding pollen. (This one contains pollen!)
Stinger at back end (pink arrow)No stingerHas a stinger

There are even more clues than this! Read all the details at Sciencing.com: How to tell if a Bumblebee is male or female.

And finally, were these two near the end of their lives?

Yes, both will die this autumn. Only fertilized queens make it through winter. Every hive starts with a lone queen in the spring.

(photos by Kate St. John)