Author: Kate Redmond

Greetings, BugFans,

The BugLady thought it was time to give this episode from 2008 a make-over – many new words and pictures.

Mayflies, order Ephemeroptera (which means “short-lived wings”) are a large and complicated group, and because the BugLady has not learned the secret mayfly handshake yet, what follows is general information about the Order Ephemeroptera.  Mayflies are not related to house flies (order Diptera).  They’re considered to have some primitive insect characteristics, and fossil evidence tells us that they’ve been around since the Carboniferous Age (354 to 290 million years ago).  Sources list 611 species in 21 families in North America (you can see physical differences in some of the mayflies pictured) and 3,350 worldwide.

Mayflies, aka lakeflies, willowflies, fishflies (though there’s a fishfly in the unrelated order Neuroptera), or shadflies (like shadbush flowers, they’re conspicuous in spring when the shad fish are spawning) have an interesting life cycle.  Immature mayflies (naiads) are aquatic, growing up in (mostly) well-oxygenated, unpolluted streams and rivers, though there are species that favor shallow, still water.  Adults are usually found at the edges of their natal wetlands.  Depending on their family, naiads live under rocks, on the stream bottom, in tunnels, or on decaying submerged vegetation, at specific depths, and within specific ranges of dissolved oxygen.  They are classified by their modes of locomotion as clingers, burrowers, sprawlers, crawlers, climbers, and swimmers, and one source calls them “microhabitat specialists.”

Most insects spend a disproportionate part of their lives as immatures, but mayflies take that to an extreme.  Depending on water temperature and water quality, the egg stage can last as long as a year and the immature (naiad) stage for three years.  Most adults live for three days, tops.

Although mayflies are most conspicuous in spring, some species are present in fall.  Like cicadas, they practice what the BugLady calls the “Normandy Beach strategy of reproduction” – if you throw enough soldiers onto the beach, some will reach the beachhead (or, in the case of the mayfly, live long enough to mate).  At their appointed time, mayflies emerge from the water, often at dawn or dusk, by the googol (more about that in a sec).  Males form dense, dancing clouds in the calm air (they are fragile) above the water.  Females fly in and pair up, and copulation is brief.  Males may dance again the next day.

Female mayflies lay 500 to 3000 eggs, singly or in batches or all at once, placing them onto/under the water’s surface while in flight or from a perch on a rock, and some species crawl underwater to oviposit.  The eggs sink to the bottom and go with the flow.  Naiads are aquatic, living under water, feeding on algae and on tiny bits of organic debris delivered by the current (adults do not have functional mouthparts and do not feed – “ephemeral”).  As they grow, naiads go through as many as two dozen molts (four times the number of molts that most insects with incomplete metamorphosis undertake).

Although they have external gills along the sides of their abdomen (the gills of species that live in still water are larger), naiads can usually absorb sufficient oxygen through their exoskeleton in well-oxygenated waters.  They use their gills to keep the water moving over their body, and this mini-current also delivers food.  Gills are used in low-oxygen situations.

When it’s time to emerge as adults, they have an unusual penultimate step.  The naiad swims to the surface or floats up on an air bubble (one source said that the naiad empties its abdomen of digested food, replaces it with air, and “becomes” the air bubble!).  It swims to shore and molts into a smoky-winged, not-quite-reproductively-mature subadult phase called a “sub-imago” or “dun.”  A few minutes to a few hours later, it molts again into the final, clear-winged adult stage called the “imago.”  The imago has longer “tails” for increased stability in flight and longer legs to grasp its mate.  For photos of molting sequence, see http://www.troutnut.com/article/10/pictures-of-mayfly-dun-molting-to-spinner.  Mayflies are the only insect that molts after reaching the winged, adult stage.

What can you mistake them for?  Because they both fold their wings above their abdomen, adults might be confused with caddisflies, which also have aquatic immatures, but the wing shape is different https://bugguide.net/node/view/1922281/bgimage.  Mayfly naiads are similar to stonefly naiads https://bugguide.net/node/view/517329, but mayflies almost always have three “tails.”  Stoneflies have two tails, and a stonefly’s gills are on its thorax.

And the Human-Mayfly Intersection?

First, as eggs, naiads and adults, mayflies are important strands of food webs in and around the water.  Eggs and naiads are a favorite food for other aquatic insects, snails, crayfish, leeches, and fish, and adults are eaten by birds, bats, dragonflies, spiders, frogs, and shrews.  Since mayflies are relished by trout, fly fisherpeople (and bait manufacturers) go to a good deal of effort to keep track of what’s emerging and to tie flies that “match the hatch.”

Second, mayflies are sensitive to changes in water quality and are indicators of clean water.  Like many other insects, their numbers are declining, most notably due to water pollution.

Finally, those dramatic, synchronized emergences of zillions of adults are cause for some lakeside and river communities to call in the snowplows in summer as the mayflies’ slippery bodies impair visibility and cover roads and bridge surfaces.  Mayflies are totally harmless but some people are allergic to large quantities of mayfly bits.  See pictures at https://www.accuweather.com/en/weather-news/mayflies-swarm-lake-erie-as-summer-kicks-off/762324 and radar at https://www.michiganradio.org/post/massive-mayfly-swarm-seen-leaving-lake-erie-weather-radar (and what an amazing shot of a mass of newly-emerged mayflies on the water’s surface!).

Nice biography and pictures here https://www.earthlife.net/insects/ephemer.html, and another bio and postage stamp at https://projects.ncsu.edu/cals/course/ent425/library/compendium/ephemeroptera.html.

For a survey of mayfly families, see https://dep.wv.gov/WWE/getinvolved/sos/Pages/Ephemeroptera.aspx.

The BugLady has no experience with this site and is not endorsing it, but she was tickled to find some mayfly wear: https://www.cafepress.com/mayflynews.

Kate Redmond, The Bug Lady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Howdy, BugFans,

The BugLady will always associate this wasp with the pandemic.  In early summer, she got an email from a BugFan who, because she was working from home (and maybe looking out the window a little bit??), noticed that the track of one her sliding windows had been stuffed with grass.  What was going on?  The BugLady sent her some info on Grass-carrying wasps and wished that she would see one someday).

Fast-forward to the Water Hemlock Wildflower Watch (of recent BOTW fame).  As she worked her way through the pictures she took on those outings, the BugLady suspected that the fuzzy, little Hymenopteran that she saw was, indeed, a Grass-carrying wasp.  Here are some nicer pictures: https://bugguide.net/node/view/1412306/bgimage, and https://bugguide.net/node/view/1592431/bgimage.

Grass-carrying wasps are, small, benign members of the wasp family Sphecidae, the Thread-waisted wasps (“thread-waisted” because their abdomen is connected to the thorax by a thin stalk called a “petiole”).  Some Sphecids are spectacular in size, shape, and color  https://bugguide.net/node/view/819298/bgpage, https://bugguide.net/node/view/1856936/bgpage, https://bugguide.net/node/view/68796/bgpage, https://bugguide.net/node/view/1572229/bgimage (all of these wasps have been featured in their own BOTWs).

Sphecids are solitary wasps; most make a nest in the ground that they provision with paralyzed invertebrates for their offspring.  The adults are pollinators that sip nectar from flowers (one article said that Sphecids prefer white flowers), drink some of the juices of the prey they collect, visit deposits of aphid honeydew, or even take advantage of hummingbird feeders https://bugguide.net/node/view/1401700/bgimage.

Counterintuitively, the Mexican grass-carrying wasp (Isodontia mexicana) is the most widespread (https://bugguide.net/node/view/34920/data) of the six genus members that occur in North America.  Bugguide.net lists a pretty reliable (but unofficial) field mark for the MGCW – a brown spot near the base of the petiole, and through the Joys of Photoshop, the BugLady was able to see it on her wasp https://bugguide.net/node/view/817656/bgimage.  Besides North America, they’ve also made their way to the UK, to Europe as far east as Crimea, and to Midway Atoll.  Not surprising considering their secretive nesting habits.

They’re found in gardens, grasslands and woodland edges, and when they’re not taking advantage of man-made “bee hotels” https://bugguide.net/node/view/1706561/bgimage and window ledges, they nest in crevices and cavities in wood, in hollow plant stems https://bugguide.net/node/view/231614, and in tunnels made by other animals (which they clean out before they add their own nest materials).  Unlike many Sphecids, MGCWs mostly nest above the ground.

Females gather blades of grass and stuff them into a nest site to form a lining (picture a ¾” wasp trailing a long piece of grass through the air https://bugguide.net/node/view/1560148/bgimage).  At the start of the process, she backs down the tube pulling the grass in behind her.  When she’s satisfied with the accommodations, she hunts for adult tree crickets https://bugguide.net/node/view/1163068, https://bugguide.net/node/view/453661/bgimage, and sometimes katydids, which she paralyzes and stows in the nest.  She lays an egg near her immobilized prey, and a stalk often contains a series of grass/tree cricket/egg units.  She finishes by stuffing the entry of her construction with a tuft of grass that some authors describe as “broom-like.”  Curiously, as the sequence of chambers lengthens, the offspring in the later cells (closer to the door) tend to be males.

There are two generations; the larvae https://bugguide.net/node/view/231618 of the first generation develop quickly – three to four weeks from egg to adult – emerging in mid-summer.  The second generation overwinters as a pupa, in diapause (suspended animation).

Despite their hiding places, the egg chambers are found by a few species of parasitic fly, and if the fly larva doesn’t kill the wasp larva outright (or starve it by appropriating its food supply), researchers O’Neill, et al found that “sharing” its food cache with fly maggots can have a “sublethal effect” on the wasp – less food results in a smaller adult wasp that may be less fit.

Several sources noted that most of the prey in a MGCW nest are adult, female tree crickets, and while this kind of gender bias is uncommon in insects as a whole, it’s common within the Sphecidae.  Researchers Ercit, Martinez-Novoa, and Gwynne took a look at this prey bias, and here are some of their observations.

• It would make more sense if males were most frequently captured, because their courtship behaviors put them at risk, out in the open.
•  “Females carrying more eggs https://bugguide.net/node/view/998532/bgimage were significantly more likely to be caught by wasps, regardless of their body size and jumping leg mass.”
• “In laboratory experiments, the number of mature ovarian eggs had a negative effect on jump distance.”

They noted that females also take risks in courtship and while ovipositing that make them more conspicuous; that females may simply be easier to catch (they’re often larger than males, especially when carrying eggs); and that some predators may have a preference for female prey because gravid females offer an added nutritional boost.

A few years ago, the BugLady purchased some iron bird silhouettes (“lawn fawns,” in her family’s vernacular) from a company called Houzz, which sells indoor and outdoor decor.  Houzz has lawn fawns galore, but they also have an on-line magazine, and in it, the BugLady found a detailed account of the MGCW https://www.houzz.com/magazine/meet-the-grass-carrying-wasp-a-gentle-pollinator-of-summer-flowers-stsetivw-vs~58817932.

Hats off, too, to the Master Gardeners of Northern Virginia for a good, well-illustrated write-up https://mgnv.org/2020/04/29/whats-that-dried-grass-doing-in-my-window-track/.

After the recent BOTW about coyotes, BugFan Tim sent this link to a video that is part of the pandemic-inspired virtual programming created by Milwaukee’s Urban Ecology Center https://www.youtube.com/watch?v=9KoNyFk6oIg&feature=youtu.be.  Enjoy.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Howdy, BugFans,

In mid-summer, water hemlock bloomed lushly in the swamps at the north end of the Bog.

A note about water hemlock (Cicuta maculata), a wetland plant that looks like Queen Anne’s lace on steroids. It’s related to the plant that killed Socrates but is in a different genus, and it’s probably the most poisonous plant in the Western hemisphere – to taste, not to touch. It can kill you within 20 minutes of eating it. Cicutoxin is a central nervous system stimulant that causes severe seizures and respiratory paralysis. Some books say that the root “smells edible” (insert BugLady eye roll here), and some people have mistaken it for the root of the edible Wild parsnip (which looks completely different to the BugLady, has yellow flowers, and grows in uplands instead of wetlands). All parts are poison (the insects are unaffected), especially the stem and root. The seeds, the least-poisonous part of the plant, look like fennel, anise, and dill seeds, and other members of the carrot family – wild food browsers beware. Despite its toxicity, small amounts of the plant were used medicinally by Native Americans, and they employed violent purges to treat accidental ingestion.

Anyway, the plants were hopping for about two weeks. Here are some of the insects that the BugLady saw – the stars of most of them are not hitched to water hemlock, it’s just that there was a ton of it in bloom and not much of anything else.

BI-COLORED PYRAUSTA – An eye-catching, day-flying moth in the Crambid/snout moth family with a wingspan of just under ¾”. It inhabits the eastern US from Texas, and its host plants are probably mints (lots of gaps in its biography). Pyrausta is Greek for “a winged insect that lives in fire.”

CARROT WASP – or Gasteruption. What a cool little wasp, with its high-arced abdomen! Bugguide.net says that “Gasteruption have a characteristic hovering flight with the swollen metatibiae hanging down so that the insect resembles a helicopter carrying a large load on a cable.” Since the BugLady has seen a helicopter carrying a large load on a cable, she will look at it with different eyes next summer. Adults are found on flowers, but their larvae are carnivores, living within the nests of cavity-dwelling, solitary bees and feeding on their larvae.

ICHNEUMON WASP, AROTES – Another classy wasp! Bugguide.net describes Arotes as “A group of boldly-patterned, medium-sized ichneumons.” The larvae of Ichneumons are mostly parasites of immature invertebrates; Arotes favors beetles – members of the metallic wood-boring, the long-horned, the false darkling, and the tumbling flower beetle families, all of which are found under bark.

PEACHTREE BORER MOTH – Each summer, hummingbird clearwing moths dance around the BugLady, mocking her camera. The Peachtree borer is from the other clearwing moth family Sesiidae, many of which are wasp-mimics (note the scale-free and therefore clear portions of the wings). Lots of internet Wanted Posters on the Peachtree borer because of the damage done by its larvae as they tunnel around within the roots and lower trunk of commercial peach, plum, and cherry trees. They are sexually dimorphic (two forms), with the more colorful female https://bugguide.net/node/view/981311/bgimage, and the equally-spectacular male https://bugguide.net/node/view/815698/bgimage.

PHANTOM CRANE FLY – The BugLady usually sees these exquisite little flies drifting in and out of the shadows at the edges of wetlands (their larvae live in the mud https://bugguide.net/node/view/1927371/bgimage). She was surprised to see this one sprawled on flower clusters (umbels). Some sources say that the adults don’t eat much, but others say that they feed on nectar.

WHITE-STRIPED BLACK MOTH – Sometimes when she’s leading a field trip, the BugLady asks people what they would name the plants and animals we see. This little moth is a no-brainer. According to Sogaard, in Moths and Caterpillars of the North Woods, Black-striped white moths have very sensitive “bat-detectors,” structures that are superfluous in a day-flying species. This suggests that the day-flying habit is relatively recently acquired.

SWEAT BEE – There are three species of sweat bee in the genus Augochloropsis – this is probably the Metallic epaulleted [sic]-sweat bee (A. metallica). Sweat bees are important native pollinators that visit a wide variety of flowers, and sometimes also eat honeydew from aphids. Female Augochloropsis dig a tunnel straight down into the earth and then make a lateral tunnel off of it. There they make cells for their eggs and provision them with pollen and nectar.

RED-SHOULDERED PINE BEETLES are members of the Long-horned beetle family Cerambycidae, whose larvae are often wood borers. Red-shouldered pine beetle larvae live in dead and decaying pine, hemlock, and fir, where their excavations help get the decomposition ball rolling.

BANDED HAIRSTREAK – Small, drab (unless newly-minted https://bugguide.net/node/view/803024/bgimage) butterflies – the BugLady searched for picture of one with its wings open, but she couldn’t find one. This is a butterfly of fields, edges, and open woodlands; males perch on vegetation to check their territory for females and for rivals (who they chase vigorously). It is suspected that ants may care for the caterpillars https://bugguide.net/node/view/803004/bgimage, as they do for some species of Azure caterpillars.

GRAY COMMA – Adults don’t visit flowers much; they get their nutrients from sap flows on damaged trees. In the Bog, gooseberries are the host plants for its spiny caterpillar https://bugguide.net/node/view/937966/bgimage. Like other “anglewings,” the Gray Comma overwinters as an adult, in a sheltered nook called a hibernaculum. The “comma” on the underside of its wings is more “V-shaped” https://bugguide.net/node/view/964668/bgimage.

ROBBER FLY LAPHRIA – Not all the insects on the water hemlock were plant feeders. This is Laphria sacrator (probably), a fairly common fly of woodlands in the eastern half of the country. Robber flies in the genus Laphria are called the Bee-like/Bee-mimic robber flies. Several kinds of robber flies surveyed the water hemlocks, looking for flying insects, including smaller robber flies, to tackle in mid-air. Size is no object.

GNAMPTOPELTA OBSIDIANATOR – The BugLady saw a few species of insects that were new to her, and this is one of them. For years, she’s been taunted by Thyreodon atricolor (https://bugguide.net/node/view/1688339/bgimage), a spectacular Ichneumon wasp that cruises through the underbrush slowly and without stopping to have its picture made. Gnamptopelta obsidianator https://bugguide.net/node/view/1803663/bgimage is its double. An expert on bugguide.net says that “I also have a feeling most of the Gnamptopelta images in the guide are misidentified Thyreodon.” Both species have been called Spider wasp mimics, too, though the BugLady is not sure what the advantage is, other than the fact that ichneumons are (relatively) docile and spider wasps have no qualms about stinging.

As if its scientific name weren’t enough of a mouthful, the BugLady found an equally tongue-twisting common name for Gnamptopelta obsidianator – the “Bent-shielded Besieger Wasp,” a translation of its scientific name. It is thought that adults may feed on nectar, but it lays its eggs on the caterpillars, especially those found on wild grapes (scroll down https://www.marylandbiodiversity.com/viewSpecies.php?species=12769).

Also seen were a click beetle, a tumbling flower beetle, several wasps and yellowjackets, a bald-faced hornet, a grass-carrying wasp (of future BOTW fame), other species of sweat bees, a daddy longlegs, a small spider, ants, a Summer Spring Azure butterfly, several species of syrphid flies, tephritid, tachinid, flesh, soldier, and green bottle flies, a dangling spider egg case, several species of Ichneumon wasps, and a White-faced Meadowhawk taking a rest.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Greetings, BugFans,

The story of this fly (whose name is considerably longer than the fly itself) demonstrates why the BugLady loves BOTW.  Could she dig up a lot of details about how this little beauty lives its life?  She could not.  But she found two interesting side stories about it.

As always, our first episode of the New Year is vocabulary-rich.

Procecidochares atra is a true fruit fly in the family Tephritidae – not one of those red-eyed, flying lab rats that circle your bowl of grapes in summer, or that escape from confinement and live in labs in perpetuity.  Those are more properly called Pomace or Vinegar flies, family Drosophilidae.  Because of the simplicity of their DNA and the ease in raising them, some Drosophila are extraordinarily well-studied and experimented on.

Fun Drosophila Fact: according to Wikipedia, if a female Drosophila melanogaster sees a female larva of an endoparasitic wasp, she will start laying her eggs on rotting fruit or some other alcoholic substrate.  Why?  Because her offspring will imbibe it, and wasps have a low tolerance for alcohol.

But we digress.

Tephritid flies are also called Picture-winged flies and Peacock flies, but those names are more properly applied to other tiny flies.  Those fancy wing patterns are used both in courtship and in defense (more about that in a sec).  Wikipedia says that the females use their telescopic ovipositors to insert their eggs in living plant material.  The larvae of most species are vegetarians, they feed on plant tissue that the eggs are deposited in, or like the genus Procecidochares, they make a gall https://bugguide.net/node/view/443421/bgimage and feed, and finally pupate inside it https://bugguide.net/node/view/857057/bgimage.  Some family members are food specialists while others enjoy a more varied menu; some are agricultural pests, and others help to control agricultural pests.  Adults feed blamelessly on nectar, pollen, honeydew, and decaying vegetation.

There are about 15 species in the genus Procecidochares in North America, all of which are gall-makers on goldenrods, and Procecidochares atra (no common name), found from the Atlantic to the Great Plains, is one of the larger and more common species (here’s a better picture https://bugguide.net/node/view/838430/bgimage).  Procecidochares atra has been recorded on three species of goldenrod.

Interesting Side Story Number 1 (and vocabulary challenge):

Most, but not all, genus members are univoltine (one generation per year), but Procecidochares atra is bivoltine (two generations).  The spring generation forms a stem gall near the base of an emerging goldenrod, and that gall is polythalamous (containing multiple larvae, as many as 21).  Galls of the late-summer generation are formed above mid-stem, often on the buds https://bugguide.net/node/view/1426536/bgimage, and are monothalamous (each houses a single larva).  The galls are leafy rosettes.  The photographer of this gall https://bugguide.net/node/view/1436982/bgimage bagged it to see what kind of fly would emerge and got wasps instead – the wasps had probably parasitized the larva of the gall-making fly (unless they were inquilines).  It’s probable that the adults overwinter and lay eggs as goldenrod starts to grow in spring.

But, as author Isaac Asimov once wrote, “The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ but, ‘That’s funny….'”  Researchers Phillips and Smith studied Procecidochares atra, noting the seasonal and structural differences in its gall making habits and identifying two new host species, Canada goldenrod and horseweed (Erigeron canadensis).  To complicate things even more, the late summer gall they found on horseweed was a stem gall located inches from the ground, not a bud gall.

What’s going on?  The researchers suspected that they might be dealing with what is called a “cryptic species,” a described species that’s actually made up of several distinct species that don’t interbreed but that look (to us) identical.  This would explain the differences in hosts and seasons and gall formation.  Although (using the tools available in the 1990’s) they were “unable to differentiate this specimen [on Erigeron] morphologically from other specimens of Procecidochares atra,” they didn’t rule out the potential for two or more cryptic species, separating the spring, fall, and Erigeron gall makers.  And, of course, they noted that there needed to be a “systematic revision of the genus.”

Interesting side story Number 2:

Yes, males use their patterned wings like semaphore flags in courtship, to signal to females, but tephritids also use them in defense.  In its write-up about the family Tephritidae, bugguide.net says

• “Some spp. mimic jumping spiders. The wing-waving apparently deters the approach of jumping spiders, important predators of the flies. 
• ‘Spider predation has been intense enough to mold the evolution of prey characteristics: predation by salticids (jumping spiders) has shaped the morphology and behavior of some tephritid flies. Their wing markings resemble the pattern of the legs of jumping spiders; the flies also wave their wings in a fashion that appears to mimic the agonistic behavior of salticids – making them ‘proverbial sheep in wolf’s clothing.’”

Researchers Greene, Orsak, and Whitman studied a tephritid in a different genus, Zonosemata (https://bugguide.net/node/view/836289/bgimage) and wrote.  “When disturbed, these flies hold their wings perpendicular to the body and wave them up and down; this resembles the agonistic leg-waving behavior typical of the jumping spider.  Zonosemata flies initiate this display when stalked by jumping spiders, causing the spiders to display back and retreat.”

A New York Times article about the study elaborates “These spiders use this aggressive behavior to warn other members of their species to stay out of their territory.

 

When the fly flaps its wings, it fools the spider into thinking it has entered the territory of another spider. As Mr. Greene put it, the fly is sending the counterfeit message ‘’I am a mean jumping spider, so come no closer.’”

For the long version (if you haven’t used up your free NYT reads for the month) see https://www.nytimes.com/1987/04/28/science/fly-mimics-attakcing-spider-to-save-its-skin.html.

A jumping spider may back away from the encounter, but the subterfuge doesn’t work on other predators, even on non-jumping spiders.  The team speculated that even though this behavior hasn’t been observed a lot, it may be more common that we think.

Confession – the BugLady has a bit of trouble seeing a spider in the fly, but if she were ¼” long, it would probably be easier.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Greetings, BugFans,

Between Christmas and New Year’s Day, it’s all reruns.  Please enjoy this slightly updated episode about a pretty little garden scourge, along with a year-end sermonette. .

This is the story of The Little Beetle That Could, of a half-inch beetle that’s much too good at what it does.  So good, in fact, that it’s on Cooperative Extension Most Wanted Posters across the US, and its emigration to foreign countries was no cause for celebration (but it did inspire some great postage stamps and educational/propaganda posters – scroll through http://www.potatobeetle.org/memorabilia.html).

One source says that the Colorado potato beetle (aka the Potato bug) (Leptinotarsa decemlineata) (“ten lines”) is among the 10 insects that everyone should know.  Gardeners from California through Central America to Florida to Nova Scotia to British Columbia certainly know it – it’s said to make itself at home in more than 3 million square miles of North America (that’s about one-third of the land mass) and close to 2.5 million square miles  of Europe and Asia. 

At the end of a BOTW about the dogbane leaf beetle (August, 2010) the BugLady threw in this “by the way” paragraph about the dogbane beetle’s infamous Chrysomelid leaf beetle relative, the CPB:

“The Colorado Potato beetle’s is an amazing story of a home-grown pest.  A native leaf beetle, its “pre-settlement” range was restricted to the Upper Missouri River Basin (alternate sources place its origins in the Rocky Mountains and/or south of the Rio Grande), where it fed unobtrusively on a few members of the Potato family like buffalo bur, ground cherry, and nightshade, in harmony with its environment.  Wherever it started, it was enough of a presence in Colorado by the mid-1860’s that the state’s name was attached to it.  When the settlers pushed West, bringing their kitchen gardens, they planted “Irish potatoes” (potatoes are native to the Andes and had been brought to the Old World a few centuries earlier, had conquered Europe, had come back across the Atlantic to New England in the 1700’s, and then headed West by wagon train).  The CPB adopted potatoes, and with its food source increasing logarithmically, it left the Plains and headed East in 1854, hop-scotching from garden plot to garden plot and arriving on the Atlantic shore twenty years later, a “reverse pioneer.”  That CPB’s had quietly switched their main host plant to potatoes was noticed when the first CPB outbreak occurred in 1859, about 100 miles west of Omaha.

Both the adults and the larvae feed on the leaves of plants in the potato family, and the people who measure these things tell us that during its entire larval life, a CPB may eat about 6 square inches of leaves, but that an adult can put away 1.5 square inches of leaves daily.  The larvae feed in groups, compounding the destruction.

No BOTW is complete without a vocabulary challenge – the humpbacked CPB larvae/grubs are cyphosomatic – their dorsal and ventral surfaces are decidedly not parallel.

CPBs are in “survival mode” 24/7.  They lay a lot of eggs on the undersides of potato leaves (as many as 800 in a lifetime), and multiple encounters with multiple partners result in lots of genetic diversity.  They grow fast, have several generations per year, and overwinter in the soil as adults so they can come out swinging when the sun warms the earth in spring.  Adults, including gravid females, may move from field to field, so all of their eggs are not in the same basket.  Add to these external/behavioral attributes the CPBs’ enviable ability to develop an inheritable resistance to almost any of the chemicals we’ve thrown at them (possibly because they’ve “practiced” by rendering harmless the naturally occurring toxic glycoalkaloids of their host plants), and you’ve truly got a force to be reckoned with.

CPBs and their eggs and larvae have a number of natural predators including some species of ladybugs, stinkbugs, and ground beetles, and CPB larvae that hatch first may cannibalize the nearby unhatched eggs of their siblings.  Home and organic gardeners can control them by hand-picking the adults, larvae, and eggs, by mulching or row covering, and by removing related weeds that feed spring adults, but our reactions to their presence have typically been chemical.

The BugLady doesn’t work for Cooperative Extension (any more) and she tries not to get embroiled in debates about pest control measures, but she’s weighing in on this one.  In a nutshell, the BugLady doesn’t like “collateral damage.”  The neonicotinoid insecticides (nicotine-like neurotoxins) that have been successful against CPBs and other agricultural pests since the mid-‘90’s (some CPBs, though, are beginning to show resistance to “neo-nics”).  Neonicotinoids have been implicated in Colony Collapse Disorder in bees – the chemicals spread throughout the treated plants, appearing in pollen and other plant parts, and they are transported back to the hive.  They disturb the central nervous system, disorienting homeward bound bees.

They also make bees (wild and domestic, solitary and colonial) more susceptible to lethal fungal and viral infections, and less dramatically, it was recently discovered that exposure to “neo-nics” causes an “insomnia” in honeybees that simply causes them to run out of steam due to sleep loss.  Thirty-five per cent of agricultural crops rely on pollinators, honey bees and native bees alike.  This group of pesticides is also bad for butterfly caterpillars, including Monarchs, and for a variety of native pollinators.

No one can blame farmers for wanting a single product that is effective across the board, and heaven knows we all want to be able to afford to eat, but the complete answer to “How much does it cost?” may take years to calculate.  This is not Either-Or; not Potatoes vs. Butterflies.  Bees are one of the canaries in our mineshaft.  Generalized pesticides kill indiscriminately, randomly lopping off strands of food webs, and that is fundamentally unsustainable.  The result will be an oversimplified world where imbalances favor outbreaks of the pests whose predators perished in the chemical or bacterial barrage, and who then require more chemicals.  And then there’s the domino effect, in which fewer insects means fewer insect-eaters, including birds, bats, spiders, and the BugLady’s beloved dragonflies and more.  A very different world.

The real questions are “Why would we think that we can eliminate organisms, disrupt eons-old connections, and lower biodiversity, and still expect the subtle systems that keep us alive and healthy to keep functioning?”  What can we do about it?

If you shake the tree of BugFans, an awful lot of scientists and educators would fall out.  So, folks, how about it?  In an era where people have drifted pretty far from the natural world, how do we bridge this “disconnect” between our actions and their ecological effects?  How do we educate people about keeping our life-support healthy?

For some great pictures, check the always-excellent University of Florida Entomology and Nematology Department’s Featured Creatures: http://entnemdept.ufl.edu/creatures/veg/leaf/potato_beetles.htm.

Meanwhile, do you want fries with that?

 

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Howdy, BugFans,

The BugLady found this beautiful, rosy Red-cross shield bug while she was wandering around at the north end of the Bog on a fine day in May.  Once upon a time, she would have been correct if she had called this a stink bug.  Stink bugs are in the family Pentatomidae, a large bunch (5,000 species worldwide) of true bugs that defend themselves, as both nymphs and adults, by producing and deploying a smelly liquid from glands in their thorax (the “penta” refers to the five segments in their antennae).  They have a conspicuous “scutellum,” that triangular-to-oblong bit of the thorax that extends back over the abdomen; their lower legs (tarsi) usually have three segments; and they have piercing/drinking straw mouthparts for sucking plant juices.

Here are some common species of Wisconsin stink bugs:

the green stink bug https://bugguide.net/node/view/1330776/bgimage;

the brown stink bug https://bugguide.net/node/view/228181/bgimage;

and a Rough stink bug https://bugguide.net/node/view/1430154/bgimage;

(and some spectacular Southern stinkbugs – https://bugguide.net/node/view/158742/bgpage, https://bugguide.net/node/view/837817/bgpage, and https://bugguide.net/node/view/1329274/bgimage).

Because of the shape of the adults, Pentatomids have also been called shield bugs, but these days, that name is more properly attached to the family Acanthosomatidae, a group that, you guessed it, was moved out of Pentatomidae and elevated to family level.

Acanthosomatidae is a small family (only six of the 180 species live in North America) that favors northern/temperate climes (and in the south, higher elevations).  Their shape is oval, their scutellum moderate, and while their antennae have five segments, their tarsi have only two.  They also have piercing mouthparts https://bugguide.net/node/view/296169/bgimage, and they can also make a stink, though the operative glands are on the abdomen.  Shield bugs have carved out a feeding niche for themselves – unlike their stink bug brethren, most of which (except the predaceous species) feed on juices of herbaceous plants, they’re found on woody plants.

Their family name comes from Greek words acanthos for “spine/thorn” and soma for “body,” which refers to a forward-pointing spine on the underside of the abdomen.  The BugLady couldn’t find a super picture of it, but she thinks you can see it right smack in the middle of this bug https://bugguide.net/node/view/643681/bgimage, near the dark tip of the mouthparts.

Another common name for the Acanthosomatidae is “Parent bugs.”

Parental care is uncommon in insects, whose usual approach to ovipositing is “lay ‘em and leave ‘em.”  Although there are instances of paternal care, most is maternal (isn’t it cool that paternal and parental have the same letters in them?).  Some species of Parent bugs protect both their eggs and the early nymphal instars from predators and parasites, which really boosts survival rates https://bugguide.net/node/view/118724.

If it’s such a good idea, why doesn’t everybody do it?  Not all family members provide hands-on care, but their eggs are not without resources – before they depart, females smear the egg surface with a substance that repels potential marauders.  The goo is created in paired, abdominal organs called Pendergrast’s organs (your esoterica for the day), and the female spreads it on the eggs with her hind legs.  Hanging around and protecting offspring can be costly physically, but producing the protective egg coating is costly, physiologically.  Research by Tsai, Kudo and Yoshizawa demonstrates that the bugs don’t do both, and that Pendergrast’s organs are reduced or absent in species that practice maternal care (which is interesting because some scientists have suggested that the organs also produce pheromones that are part of the courtship).

The BugLady couldn’t find a lot of life history information about the Red-cross shield bug (Elasmostethus cruciatus) (cruciatus means “crossed” and refers to dorsal markings).  They’re found across the continent as far south as northern Georgia and far north into Canada, but uncommonly on the Great Plains.  Their host plants are alder, with maybe some birch thrown in.

Elasmostethus genus members do not provide maternal care for their young.  Based on biographies of other genus members, the RCSB does not put all of her eggs in one basket; she lays lots of small batches of eggs (predators may find some, but not all), and she places them near the developing fruits of alders (a European member of the genus sometimes cannibalizes the eggs of her sisters).  A group of newly-hatched nymphs will hang around their empty eggs until their first molt, and then they start puncturing the fruits.  Here’s a nice collection of pictures http://somethingscrawlinginmyhair.com/2015/03/28/red-cross-shield-bug/.

The Red-cross shield bug that the BugLady spied in May was nearing the end of its life cycle.  They overwinter as adults in sheltered spots, and procreate and die when the warm spring air wakes the plants.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Greetings, BugFans,

The BugLady is living proof that there’s a big difference between looking and seeing.  For years, she’s been photographing these little black and yellow wasps and filing them under “Potter wasps,” but she had an “Oh Duh” moment this summer, and yeah, yeah – she sees it now.  As Henry David Thoreau once said, “We must look a long time before we can see.”

So – not potter wasps https://bugguide.net/node/view/1906174/bgimage – these are Square-headed wasps in the family Crabronidae.  Members of the family were formerly placed in the Thread-waisted wasp family Sphecidae, a family that includes some conspicuous beauties like the Blue mud dauber, the Black and yellow mud dauber, the Great golden digger wasp, and the Great black wasp, but now they’re viewed as a separate family.  Stand by for further taxonomic tweaking.

We have visited the Crabronidae before, in the form of the organ-pipe mud daubers (https://uwm.edu/field-station/organ-pipe-mud-dauber/) and the sand wasps (https://uwm.edu/field-station/sand-wasps/).  It’s a large and diverse bunch, with about 9,000 species worldwide (1,225 in North America).

The name “Square-headed wasps” only applies to species in the subfamily Crabroninae, which has 4,700 species (520 here) – a number of sources call them digger wasps.

Square-headed wasps are solitary wasps that use their impressive jaws (https://bugguide.net/node/view/1684606/bgimage) to make nests in the ground, in hollow stems, in the pith of broken stems, and in old galleries (tunnels) chewed in wood by beetle larvae.

Solitary wasps typically create an egg chamber and stuff killed/stunned/bitten/stung spiders and/or small insects into it (scroll down to the fly-stuffed stem https://prairieecologist.com/tag/ectemnius/).  Here’s a Square-headed wasp with a crane fly https://bugguide.net/node/view/110413/bgimage.  Mom lays an egg on one of the bodies, closes the chamber up, and moves on.  The carnivorous larva hatches out into its own personal pantry stocked with enough food to get it to the pupal stage.  Some species of Crabronids, like the sand wasp above, do what’s called “progressive provisioning” – instead of providing a cache, the female sticks around her egg tunnels and brings food to her developing young – but Square-headed wasps seem to use the standard method.  Many Square-headed wasps are very specific about the kinds of insects they pursue.  Adults feed on nectar.

The first question (but never the last, of course) is “which Square-headed wasp is this?” Alas, the BugLady can’t provide a definitive answer.  She thinks she’s photographed several species, and she’s been squinting at pictures until she’s cross-eyed, and she’s guessing that her wasps are either in the genus Lestica https://bugguide.net/node/view/624516/bgimage (three species in North America) or Ectimnius https://bugguide.net/node/view/1406440 (27 species), or Crossocerus https://bugguide.net/node/view/214928/bgimage the Equilateral Square-headed Wasps (!) (40 species in North America but only a few have yellow markings on the abdomen).  They are differentiated by field marks like the sharpness of the longitudinal grooves along the inner eye margin.  BugFans are always welcome to weigh in.

Their MO’s are similar, differing slightly in the medium they pick for their egg chambers and the type of insect they hunt in behalf of their young.

The BugLady gives Thanks for the six-legged and the eight-legged and the no-legged.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Salutations, BugFans,

Here’s a rerun from August of 2014.

What a magical little fly!

Most BugFans are familiar with crane flies, those giant, non-biting “mosquitoes” in the family Tipulidae https://bugguide.net/node/view/1895587/bgimage (some of the fall-flying crane flies in the family Pediciidae (the Hairy-eyed Crane Flies) are pretty spectacular too https://bugguide.net/node/view/147834/bgimage).   Phantom crane flies belong in the small family Ptychopteridae (only three genera).  Crane flies were named for their long legs, and most authors attribute the “phantom” part of the name to the way Phantom crane flies drift through the air, appearing and disappearing in patches of light and shadow.  Our Phantom crane fly (Bittacomorpha clavipes) can be seen east of the Rockies, from late spring to early autumn, in the fairly dense vegetation along the shady edges of wetlands.

They aren’t huge.  If you join the tips of your thumb and forefinger, you’d be approximating the leg-span.  They’re like a flying daddy long-legs, but without the bulk – a Phantom crane fly’s body is a slender half-inch.  Sources describe them as floating through the air, legs spread, flapping their wings minimally, assisted aerodynamically by the flared areas on their legs.  Can they fly up-wind?  Yes, if the breeze isn’t too strong, but most of the time, they appear to move randomly through the vegetation, two or three feet off the ground, ricocheting off of leaves.

The odd flanges on the legs are a characteristic of this species.  Twentieth century entomologist C. P. Alexander (who described more than 11,000 species and genera of flies during his long career) said of the Phantom crane fly that “This species is one of the most conspicuous and interesting of all Nearctic Diptera. The first tarsomere of the legs is dilated and filled with tracheae, a characteristic which enables the flies to drift in the wind with their long legs extended to catch the breeze.“

Let’s “unpack” the trachea-tarsomere thing.  The tarsus is the lower part of an insect’s leg – its “foot” – located below the tibia.  It’s made up of a series of small segments (usually five) called tarsomeres; the top segment is called the metatarsus, and the bottom segment usually bears a claw or two.  The insect walks or hops on its tarsus.

Insects breathe largely by diffusion, and their respiration is mostly passive (although muscle contractions can push air through the respiratory system more quickly).  Air floats through openings called spiracles into tubes called trachea.  It moves through a network of increasingly minute respiratory tubing that divides and subdivides and ends in moist pockets called tracheoles where the cells can exchange waste gases for fresh.  Trachea may be strengthened by spiral fibers called taenidia that are embedded in their walls; taenidia have been likened to the coils in a dryer vent tube.  In the absence of taenidia, a tracheal wall may bulge out like an aneurism and form an air sac.

Still unpacking.  In his article called “Peculiar Tracheal Dilations in Bittacomorpha clavipes,” published in the Biological Bulletin in 1900, Charles Thomas Brues explains further.  “In both sexes, the metatarsi are very much enlarged and quite conspicuous on account of their great color contrast. The whole tibia is completely filled up by the trachea.  In the enlarged metatarsus, the trachea is enormously distended and almost completely fills the cavity of this joint as well as that of the second and third joints of the tarsus.”  In Tipulidae, the tracheal tube is delicate-to-obsolete in the tarsus.  “it is impossible that they [immense vesicles in the metatarsi] should be used as reservoirs for air for respiration, on account of their distance from the body of the insect.  It is more probable that they may bear some relation to the insect’s method of locomotion.  When flying, Bittacomorpha uses the wings scarcely at all, relying in great measure upon wind currents for transportation.  The legs are exceedingly light, as the exoskeleton is light and delicate, and encloses practically no tissue that can serve to increase their weight.  As they expose a large surface, they offer great resistance to the air without adding appreciably to the insect’s weight.

So, the hollow legs lighten the insect, and the inflated sacs increase buoyancy and provide surface area for the wind to push on.

How do Phantom crane flies get away with their striking, black and white patterns?  Aposematic/warning coloration has been suggested, but the folks who keep track of these things tell us that the rest of the crane flies taste OK, and there’s no reason to suspect that Phantom crane flies taste otherwise (the aquatic larvae scavenge on organic detritus in the water that surrounds them, and the adults eat little or nothing (though the one on the white flowers looks like it might be nectaring), and they’re not blood suckers!.  Nothing suspicious there).  As previously noted, black and white coloration is a good plan for an animal that inhabits the light-speckled thickets, and the BugLady assumes that they’re as tough for predators to see as they are for photographers.  A blogger in Michigan suggests that Crane fly legs are oh-so-easily detachable, and that a Phantom crane fly may sacrifice a conspicuously-striped leg to save its life.

Clearly, Phantom crane flies have caught our fancy, and it’s fun to note the words that are used to describe them and their flight:

• “They resemble a spider web or a thistle seed drifting about.”
• “It looks a bit like a flying snowflake.”
• “It hangs or floats in the air rather than flies, spreading its long legs to catch the breeze, a little like ballooning in spiders.”
• “They appear like parachutes floating above streamside grasses and sedges.”
•  “When the legs are vibrate, this insect indeed lives up to its name, giving the beholders a sensation of “spots before the eyes.”
• The same Michigan blogger notes, interestingly, that “When it flies, it looks like a tight swarm of up to seven small flies, rather than a single large one.”

If the BugLady were to pick an adjective, it would be “flickering,” and she thinks they look like tiny sparklers.

The BugLady was lucky enough to witness a few happy Phantom crane fly couples flying around in tandem.  Both in flight and when hanging from a leaf, the female does the heavy lifting.  Twice, as the BugLady was (voyeuristically) photographing a mating pair, a third Phantom crane fly flew in and hassled the female.

Subsequently, the female dips the tip of her abdomen into the water, depositing eggs (as many as 300 of them) singly or in small bunches.  The larvae live in the top inch or so of muck and feed on decaying material they find there.  It’s not exactly an oxygen-rich environment, and although they can pick up gases through their soft exoskeleton, they get the bulk of their air through a long, retractable breathing tube (caudal respiratory siphon) that they extend up through the surface film from the rear of their body.  According to Voshell in A Guide to Common Freshwater Invertebrates of North America, the larvae “burrow deep into sediment during periods of the winter when the water freezes over.  Pupation occurs in the same habitat where the larvae develop, without any special preparation.  Pupae have long, breathing tube on the thorax.”  There are reportedly two broods in the northern part of its range.

Phantom crane flies have been putting on small but exquisite performances since Eocene times, and they’re now showing at a wetland near you!

On another note – the BugLady has been enjoying the sweet serenades of the tree crickets recently.  Here are links to two audio sites from last year’s BOTW on tree crickets:  Go to http://www.oecanthinae.com/4099.html, turn up the volume on your speakers, and scroll down slowly.  And, try the U of Florida’s recordings of crickets and katydids north of Mexico at http://entomology.ifas.ufl.edu/walker/buzz/cricklist.htm.  Fair warning – you have to listen pretty hard to hear some tree crickets.

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/

Howdy, BugFans,

Last week’s episode was the 600^th original (not rerun or tweaked) episode, and the BugLady is going to take a two-week victory lap (but she will fill the space with tasteful reruns).

The BugLady has been hanging out on the hawk tower this fall, logging migrating raptors for the Western Great Lakes Bird and Bat Observatory.  We’ve counted just under 800 birds since early September, and some of the weather has been – interesting.  On Sunday, the temperature was in the high 30’s (-ish), and we clocked a few wind gusts around 40 – and got 37 birds.  The BugLady was amazed to see, on the walk back to the car, a few wooly bear caterpillars crossing the mowed trail.  Those little fur coats must be a lot warmer than they look.

Without further ado, here’s a slightly up-dated version (some new words, a few new pictures) of a rerun from 2015, which was a slightly up-dated version of the 2009 original.

Greetings, BugFans,

As often happens with the moths, one life stage may be more conspicuous, and the adults and caterpillars may even have different names.  In this case, the ubiquitous, rust-and-black-banded Wooly bear caterpillar turns into a lovely, less-common, caramel-colored, or cream https://bugguide.net/node/view/1636191/bgimage, or yellow https://bugguide.net/node/view/1237224/bgimage) moth called the Isabella Tiger moth (Pyrrharctia Isabella).  Pyrrharctia is a “monotypic genus” – there’s only this single species in it – and they’re only found in North America.

Tiger moths are in the family Erebidae, a diverse group that includes about 250 species of tiger, underwing, Zale, tussock moths, etc. in North America and many more worldwide (except Antarctica).  If you have an older insect guide, they’re in their own family, Arctiidae, but everything that was once in Arctiidae is now in subfamily Arctiinae.

Tiger moths are unusual in that they have an organ on their thorax that vibrates to produce ultrasonic sound.  They “vocalize” to attract mates and to defend against predators.  If you have sound-making ability, you also need “ears,” and those are on the thorax, too.  Like the feline tigers, the adults of many species are hairy and sport bold color patches, stripes or patterns (consider the striking Leconte’s Haploa https://bugguide.net/node/view/954015).

Many tiger moth caterpillars are fuzzy, earning a group name of wooly bears or wooly worms. There is an amazing amount of information out there about wooly bear caterpillars, and much of it is contradictory, which is explained by the fact that there are many different kinds of caterpillars that are called Wooly bears.

The Isabella Tiger Moth caterpillar is called the (generic) Wooly Bear, the Black-ended Bear, and the Banded Wooly Bear (they’re not as distinctive in their early stages https://bugguide.net/node/view/1617463/bgimage).

A mature female Isabella Tiger Moth “calls” to males by emitting pheromones (chemical signals) at night, and males use their sensory antennae to zero in on her https://bugguide.net/node/view/1837707/bgimage.  Isabella Tiger Moths lay their eggs https://bugguide.net/node/view/1186437/bgimage on a wide variety of plants during the warm months.  While some caterpillars are known for their picky eating, Wooly bears are generalists.  They feed during the day, munching on handy, low-growing plants like grasses, “weeds,” and wildflowers (cannibalism has also been reported).  Their catholic eating habits ensure that they’re constantly surrounded by food during their autumnal wanderings in search of wintering sites.

They spend the winter as caterpillars, sheltered from the weather under tree bark or debris, or in your garage.  Do they become “bug-cicles”?  Yes, indeed – they’ve even been found frozen into a chunk of ice.  But, like other organisms that are dormant in the dead of winter, Wooly bear caterpillars produce a chemical cryoprotectant (antifreeze) that safeguards living tissue against damage from freezing and thawing.  They will stir and walk around on mild winter days and go back into hiding when the temperatures drop again.  They wake up with the warm weather, resume eating, and then pupate in late spring in a fuzzy cocoon into which they incorporate their own “hairs.”  According to Wikipedia, Arctic summers are so short that Arctic Wooly bears may need to live through several of them to become mature enough to pupate.

One area of disagreement among sources is whether Wooly bears’ wool/setae/hairs/bristles are irritants (remember: one common name – numerous species).  Having a bristly covering discourages some predators, although in the Fieldbook of Natural History, E. L. Palmer says that “skunks and a few other animals roll hairs off the caterpillars before they eat them.”  Certainly, the stiff hairs make it a harder to pick a Wooly bear up, and when you do pick one up and it curls into a defensive ball https://bugguide.net/node/view/1454009/bgimage, it’s pretty slippery.  Some sources say that the setae contain a stinging/irritating/venomous chemical, and other sources specifically say they do not.  Still other references say the setae may cause dermatitis mechanically – that they might break off in your skin (like one of those wretched, furry cacti); and others say that that unlike many hairy caterpillars, Wooly bears are harmless.  The BugLady has never suffered any ill effects from handling the familiar, rust-and-black Wooly bears.

Wooly bears have been famous since Colonial times for two things: 1) their habit of crossing the roads in fall (the BugLady wonders what they crossed before the Colonists arrived and started making roads); and 2) their (alleged) ability to predict the weather.

The weather lore angle was initiated by those same, road-building Colonists, who needed some forecasting done in the pre-Weather Channel days so they could figure out when to plant and harvest crops.  If its rust-colored middle band is wide, says the Almanac, the winter will be a mild one; if there is lots of black, batten down the hatches (except for a few sources that say the opposite – that lots of rust means lots of cold).

A surprising number of scientists have felt obligated to leap in and deflate the weather story.  To them the BugLady says “Lighten up, Party Poopers, and let a little fantasy into your lives.”  They tell us that the widening middle band is a result of age; that each time a Wooly bear molts, a black band becomes a rust band (except, of course, for a few who say the opposite – that rust turns to black).  So, a rustier caterpillar is an older caterpillar.  The BugLady had been curious about why the early fall Wooly bears seemed more pessimistic than the later fall Wooly bears and is happy to have that one resolved. According to that school of thought, if you see a blacker caterpillar in spring, it’s one that became dormant prematurely, and so may be telling the weather of the previous fall.  Other research suggests that a caterpillar with lots of rust lived in dry conditions, and one source says that a Wooly bear with wide black bands grew up where the habitat was wetter.  Still other scientists say that there is considerable variation in color even within newly-hatched individuals from a single clutch of eggs, and that the variation persists as they age.

We have Dr. Curran, a curator of insects at the American Museum of Natural History, to thank for popularizing the Wooly bear.  For eight years in the late 1940’s and early 1950’s, Dr. Curran drove north from New York City along the Hudson to Bear Mountain State Park to measure the coloration of the Wooly bears he found there.  During those years, the rusty bands predicted mild winters.  He “leaked” the forecasts via a friend at a NYC newspaper, and the publicity his reports generated put Wooly bears on the map.  But Dr. Curran’s only real hypothesis was that Scientists Just Want to Have Fun.  He and his friends enjoyed the scenery, the foliage, and the caterpillars on their annual fall forays and formed “The Original Society of the Friends of the Woolly Bear.”  Thirty years after Dr. Curran’s outings ceased, the folks at Bear Mountain State Park resurrected the Friends organization and the wooly bear count.

Wooly bears are embraced by children and adults alike, and Annual Wooly Bear Festivals are observed in fall (though the pandemic has shuttered many):

• in Beattyville, KY, launched in 1987, caterpillars race up dangling strings http://www.beattyville.org/tourism/feastivals-and-events/;
• in Vermillion, OH, begun in 1973, which features a costume contest for children and pets https://www.vermilionohio.com/woollybear-festival/;
• in Banner Elk, NC, started in 1977, highlighting a race with more than 1,400 racing caterpillars; the winner gets to make the forecast http://www.woollyworm.com/;
• in Oil City, PA, where boosters hope that the fall Woolly Bear Jamboree will someday rival the Groundhog Day celebration in Punxsutawney;
• in Lewisburg, PA, where the celebration includes a pet parade https://www.dailyitem.com/news/local_news/woolly-worm-festival-revived-at-new-union-county-locale/article_78c18a39-c667-5a18-b70b-2f10b7d89505.html http://www.woollywormfestival.com/;
• Lion’s Head, Ontario, Canada
• in Little Valley, New York, browse local arts and crafts and meet WILMA the Wooly bear https://enchantedmountains.com/events/2019/10/7th-annual-wilma-8599;
• Milwaukee has scheduled its Woolly Bear Fests in January because – partying in the snow.

By the way – both “wooly” and “woolly” are accepted spellings, but in countries that are not the US, “wooly” is likely to be spelled “woolly.”

Kate Redmond, The BugLady

Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/