Bug o’the Week – The Monarch Butterfly Problem

Bug o’the Week
by Kate Redmond

The Monarch Butterfly Problem

Howdy, BugFans,

The BugLady wrote this for an upcoming newsletter of the Lake Michigan Bird Observatory (an organization that would love your support).  It started out as a simple report about this year’s survey of overwintering Monarch Butterflies, but then it took the bit in its teeth and became oh-so-much more.  Put your feet up.

Every fall, most of the Monarch Butterflies east of the Rockies set their compass for a small patch of mountains just northwest of Mexico City.  This winter’s count of eastern Monarch Butterflies (Danaus plexippus plexippus) overwintering in the oyamel fir forests of central Mexico was the second lowest since annual censusing began in 1993.  In the 1990’s, the eastern Monarch Butterfly population was estimated at 70 million, and today’s numbers represent an 80% decline in population.

The census is not an actual nose-count of the butterflies themselves but is a measurement of the area they occupy.  They’re densely concentrated on their wintering grounds — scientists estimate between 20 and 30 million Monarchs per hectare (about 2.5 acres).  The lowest area, 0.67 hectares (1 66 acres), occurred 10 years ago, and the largest ever, in 1996-97, found 45 acres occupied.  This year, Monarchs were seen on 0.9 hectares (2.2 acres), down 59% from the 2022-2023 season (Dr. Karen Oberhauser, founder and director of the Monarch Larva Monitoring Project (https://mlmp.org/), points out that 2.2 acres is smaller than two football fields).  It’s felt that almost 15 acres of overwintering butterflies are needed to maintain a healthy eastern population.  “Monarch populations [are] at a level that most scientists suggest is not sustainable,” says Dr. Oberhauser.  Western Monarchs, residents and migrants along the Pacific Coast, are treated as a separate population.   

Migration is expensive, energy-wise, and is dangerous, and the list of hazards is long.  Land use changes and habitat loss, herbicides and pesticides, loss of milkweed, car-butterfly collisions, climate change that brings harsh winter conditions to central Mexico or storms as the butterflies prepare to depart, or that puts migrating butterflies out of sync with nectar plants on their spring migration, high temperatures that reduce the nutritional value of milkweed plants, and severe drought along the fall migration route through “the Texas Funnel” have all been suggested as factors.

The integrity of the fir forests themselves is critical, but the illegal logging that has reduced the forest size and cover in the past was held to a minimum last year.  The butterflies depend on a dense forest to act as insulation so they don’t have to expend as much energy staying warm, dry, and hydrated. 

Quick review of Monarch biology and migration — there are four or five generations annually, and the last brood of the year is extraordinarily long-lived for a butterfly.  It emerges in August or September, and while the earlier generations are reproductively active, this final generation is not.  Signaled by decreasing day length, lowering angle of the sun, cool nights, and increasingly leathery milkweed leaves, their reproductive organs don’t mature.  Instead, they apply their energy to a journey – a leisurely trip that can cover more than two thousand miles and take two months.  The butterflies feed on nectar from a wide variety of flowers as they wend their way south, and while a newly-emerged Monarch in Wisconsin has about 20 mg of fat in its body, a Monarch newly-arrived in the oyamel fir forests of Mexico may carry 125 mg of fat.  They eat little on their wintering grounds. 

With the warming temperatures of late March, they become reproductively ready and head north through northern Mexico and our Southern states, laying eggs as they go, careful not to get ahead of the emerging milkweed plants.  Their young — the first-generation offspring of the Mexican butterflies — keep moving and recolonize the north, often arriving in Wisconsin in mid-May and in Canada shortly after that (Southern summers are too hot for the caterpillars to thrive).

Their offspring – the second generation out of Mexico, continue to lay eggs and may fly a little farther north, but most have reached their destinations by the end of June.  The “job” of this short-lived generation (and of the next generation, if there’s time for one) is to stay put and use their energy to build up the population.  The migratory final generation, sometimes called Gen 5 or the Super Generation, is the only one that is tagged. 

This complicated dance depends on good weather, milkweeds for caterpillars, and abundant nectar plants for adults.  Monarchs will lay their eggs on a variety of milkweed species, but Common milkweed is the favorite. 

Follow the northward wave of Monarchs here https://maps.journeynorth.org/map/?map=monarch-adult-first&year=2024.

There have been passionate efforts in past years to list the Monarch as an Endangered Species under the Endangered Species Act (ESA).  Classification under the ESA is a lengthy process, there are many other deserving candidates, and listing requires both a recovery plan and a dedicated budget https://uwm.edu/field-station/bug-of-the-week/listing-the-monarch/.   

Monarch populations are subject to wide swings, but a low year followed by another low year lessens the possibility of a speedy comeback.  Overall population levels in the summer of 2023 were not alarming, but severe heat and drought in the Texas Funnel migratory corridor probably resulted in fewer Monarchs finishing their journey to Mexico. 

Based on a few recent studies, there are voices, even voices within the Monarch Butterfly community, that suggest (counterintuitively) that there’s no need to change the Monarch’s status, citing past population plunges and recoveries.  The International Union for Conservation of Nature (IUCN), a leading scientific authority on the status of species, recently downgraded Monarchs on their Red List of Threatened Species from Endangered to Vulnerable. 

Some of the arguments are historical.  Monarchs like milkweeds, and milkweeds like sunshine, and the treeless Great Plains is thought by some to be the historical center of both Monarch and milkweed populations.  Too, there was lots of sunshine during the long postglacial period while trees moved back north after the most recent glacier pushed them south, and some speculate that milkweeds and Monarchs took that opportunity to push east and increase their numbers before the forests regrew. 

The early settlers cut down swathes of America’s Great Eastern Forest to establish villages and farms, making the area sunnier and more Monarch/milkweed-friendly, and some say that Monarch populations are larger now than they were 200 years ago.  Today, they say, Monarchs are adapting to modern stressors, and they’re establishing some non-migratory breeding communities in Florida and around the Gulf Coast.  Monarchs, some scientists say, are not at risk, but the eastern Monarch migration may be (a distinction without a difference to Monarch lovers).   

Did the Monarch’s eastward expansion into a glacially-modified landscape and later into a human-modified landscape artificially boost their numbers, so that what’s happening today is just a “course correction?”  Should we base the butterfly’s status on the wintering numbers rather than the summertime population?  On today’s numbers vs long-time averages?  Is it better to err on the side of caution?”  Will there, as Chip Taylor of Monarch Watch says “always be Monarchs?”

Only time –- and more research — will tell who’s got it right.  In the meantime, what can we do to help? 

Kate Redmond, The BugLady

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

Bug o’the Week – The 12 (or 13) Bugs of Christmas

Bug o’the Week
by Kate Redmond

Bug o’the Week The 12 (or 13) Bugs of Christmas

Greetings of the Season, BugFans,

(13 bugs, because once she’s got her selection down to 13, the BugLady just can’t cut one more!)

A Cheery Thought for the Holidays, the average home contains between 32 and 211 species of arthropods (with the lower numbers at higher Latitudes and higher numbers as you head south past the Mason-Dixon Line).  So, while the BugLady is celebrating The 12 (or 13) Bugs of Christmas, most BugFans could rustle up at least that many under their own roofs.  Whether you see them or not, all kinds of invertebrates coexist with us daily, mostly staying under our radar until we surprise each other with a quick glimpse.

Here are a baker’s dozen of the bugs that the BugLady saw in 2023.

BALTIMORE CHECKERSPOT CATERPILLAR – According to one researcher, caterpillars are “essentially bags of macerated leaves.”  What kind of leaves does a Baltimore Checkerspot caterpillar macerate?  The eggs are laid in the second half of summer on, historically, White turtlehead, a native wildflower, and more recently, Lance-leaved plantain has been added as a host plant.  Both plants contain chemicals that make the caterpillars distasteful to birds, though the turtlehead has higher concentrations of them.  The butterflies have adapted to use an introduced plant, but the caterpillars don’t do as well on it (the BugLady has also seen them on goldenrod).  Half-grown caterpillars overwinter, and when they emerge to finish eating/maturing in spring, the turtlehead isn’t up yet, so they eat the leaves of White ash and a few spring wildflowers.   

LEAFCUTTER BEE ON PITCHER PLANT – Bumble bees and Honey bees are listed as the main pollinators of Purple pitcher plants, along with a flesh fly called the Pitcher plant fly (Fletcherimyia fletcheri), a pitcher plant specialist that contacts the pollen when it shelters in the flowers.  But it looks like this Leafcutter bee is having a go at it. 

SEVEN-SPOTTED LADYBUGS had a moment this year; for a while in early summer, they were the only ladybug/lady beetle that the BugLady saw.  Like the Asian multicolored lady beetle, they were introduced from Eurasia on purpose in the ‘70’s to eat aphids.  But (and the BugLady is getting tired of singing this chorus) they made themselves at home beyond the agricultural fields and set about out-competing our native species. 

An Aside: Lots of people buy sacks of ladybugs to use as pest control in their gardens.  The BugLady did a little poking around to see which species were being sold.  Some sites readily named a native species, but most did not specify.  Several sites warned that unless you are buying lab-grown beetles, your purchase is probably native beetles scooped up during hibernation, thus posing another threat to their numbers

SOLDIER FLY LARVA – The BugLady is familiar with Soldier fly larvae in the form of the flattened, spindle-shaped larvae https://bugguide.net/node/view/1800040/bgimage that float at the surface of still waters, breathing through a “tailpipe” and locomoting with languid undulations.  So she was pretty surprised when she saw this one trucking handily across a rock in a quiet bay along the edge of the Milwaukee River.  It appears to have been crawling through/living in the mud. 

COMMON WOOD NYMPH – And an out-of-focus Common Wood Nymph at that.  The BugLady has a long lens, and her arms weren’t quite long enough to get the butterfly far enough away to focus this shot.  And it’s really hard to change lenses with a butterfly sitting on your finger.

FALSE MILKWEED BUG – Milkweed bugs are seed bugs that live on milkweeds, but if you’ve ever seen a milkweed bug that was not on a milkweed (usually on an ox-eye sunflower), it was probably a False milkweed bug.  They’re so easily mistaken for a Small milkweed bug that one bugguide.net commentator said that all of their pictures of Small milkweed bugs should be reviewed.  Here’s a Small milkweed bug with a single black heart on its back bracketed by an almost-complete orange “X” https://bugguide.net/node/view/2279630/bgimage; and here’s the False milkweed bug, whose markings look (to the BugLady) like an almost complete “X” surrounding two, nesting black hearts https://bugguide.net/node/view/35141.  One thoughtful blogger pointed out that although it looks like a distasteful milkweed feeder, it’s not thought to be toxic.  He wondered if this is a case of mimicry, or if the bug once fed on milkweed, developed protective (aposematic) coloration, and then changed its diet?

LARGE EMPTY OAK APPLE GALL – That’s really its name, but “empty” refers to the less-than-solid interior of the gall https://bugguide.net/node/view/54459 (which was made by this tiny gall wasp https://bugguide.net/node/view/260612).  Galls are formed (generically) when a chemical introduced by the female bug that lays the egg, by the egg itself, and later by the larva, causes the plant to grow extra, sometimes bizarre, tissue at that spot.  The gall maker lives in/eats the inside of the gall until it emerges as an adult.  Some galls are made by mites – same principle.

SYRPHID FLIES are pretty hardy.  Some species appear on the pussy willows and dandelions of early spring, and others nectar on the last dandelions of late fall.  This one was photographed on November 17, on a sunny and breezy day with temperatures in the low 40’s, 12 feet off the ground, resting on the BugLady’s “go-bag” (the bag of extra clothes she carries up onto the hawk tower to deal with the wind chill).

WASP WITH SPIDER – The BugLady saw a little flurry of activity near an orbweaver web on her porch one day, but she got it backward.  At first she thought that the spider had snagged the wasp (a Common blue mud dauber), but it was the wasp that hopped up onto the railing with its prey, part of the spider collection she will put together for an eventual larva.

SIX-SPOTTED TIGER BEETLES grace these collections perhaps more than any other insect, because – why ever not!

JUST-EMERGED DAMSELFLY – This damselfly was so recently emerged (possibly from the shed skin nearby) that its wings are still longer than its abdomen (basic survival theory says that you put a rush on developing the parts you might need most).  Will a few of the aphids on the pondweed leaves be its first meal?

This is either a GREEN IMMIGRANT LEAF WEEVIL (Polydrosus formorus https://bugguide.net/node/view/1678834/bgimage) or the slightly smaller (and equally alien) PALE GREEN WEEVIL (Polydrosus impressifrons https://bugguide.net/node/view/1813505/bgimage).  Whichever it is, it’s been in North America for a little more than a century.  Bugguide.net calls them “adventive” – introduced but not well established.  Eggs are laid in bark crevices or in the soil, and the larvae feed on roots.  Adults eat young leaves, buds, and flowers of some hardwood, fruit, and landscape trees but are not considered big pests.  Their lime-green color comes from iridescent, green scales.

And a DOT-TAILED WHITEFACE in a pear tree.

Have a Wonder-full New Year,

Kate Redmond, The BugLady

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

Bug o’the Week – Wildflower Watch – Swamp Milkweed

Bug o’the Week
by Kate Redmond

Bug o’the Week Wildflower Watch – Swamp Milkweed

Howdy, BugFans,

The BugLady is already fantasizing about warm, sunny days in a wetland, photographing Swamp milkweed (and dragonflies), because she loves its color, and she loves being in wetlands, and because it’s a very busy plant, indeed!

Also called rose or red milkweed (there are a couple of species of southern milkweeds that are also called red milkweed), white Indian hemp, water nerve-root, and water silkweed, Swamp milkweed prefers damp soils and full sun near the water’s edge.

Indians, and later, the European settlers, used it medicinally (a tea made from the roots was reputed to “drive the worms from a person in one hour’s time”).  It was used with caution – its sap is poisonous – and the cardiac glycosides that protect Monarchs also deter mammals from grazing on all but the very young plants.  The fibers in its stem were twisted into rope and twine and were used in textiles.

Its flowers are typical milkweed flowers – a corona of five parts (hoods) with curved petals below and curved, nectar-secreting horns above.  The flowers are tricky – sticky, golden, saddlebag-shaped pollinia are hidden behind what one author calls a trap door (a stigmatic slit).  Insects walk around on the flower head, and when one of their feet slips through the slit by chance, a pollinium sticks to it.  When the bug encounters a stigmatic slit on the next plant it visits, the pollen is inadvertently delivered.  A quick-and-dirty, pick-up and delivery is what the plant had in mind; but, like the story of the raccoon (or was it a monkey) that reaches into the jar for a candy bar and then can’t pull its fist out of the small opening, sometimes the insect’s foot gets stuck to pollinia inside the trap door.  Insects that can’t free themselves will die dangling from the flower, and insects that escape may be gummed up by the waxy structures.  Look carefully for pollinia in the pictures.

Milkweeds support complex communities of invertebrates – their nectar attracts ants, bugs, beetles, flies, butterflies, moths, bees, and wasps, plus predators looking for a meal.  Here are some of the insects that the BugLady sees on Swamp milkweed.

TWO-BANDED PETROPHILA MOTHS (Petrophila bifascialis) are delicate moths that lead a double life.  By day, they sit sedately on streamside vegetation.  By night, the female crawls down the side of a rock into the water – sometimes several feet down – to deposit her eggs on the stream bottom, breathing air that she brings with her, held against her ventral surface (“Petrophila” means “rock-lover”).  Her larvae eventually attach themselves to a rock and spin a net to keep themselves there, feeding on diatoms and algae that they harvest from the rock’s surface with their mandibles. 

MULBERRY WING SKIPPER – A small (one-inch-ish wingspan) butterfly of wetlands with an arrow or airplane-shaped marking on its rich, chestnut-brown underwings (the upper surface of its wings looks completely different https://bugguide.net/node/view/34033/bgimage.  Adults fly slowly through low vegetation, where females lay their eggs on the leaves of sedges. 

FLOWER LONGHORN BEETLE BRACHYLEPTURA CHAMPLAINI (no common name), on a Swamp milkweed leaf.  Other than a “present” checkoff in a variety of natural area insect surveys, there’s just about nothing online about this beetle, and not much more in Evans’ book, Beetles of Eastern North America.  It’s a long-horned beetle in the Flower longhorn subfamily Lepturinae, a group that feeds on pollen in the daytime.  This one has pollinia on its mouthparts.

AMBUSH BUG – The dangling bee in this picture did not fall victim to the sticky pollinia (though it has plenty of them on its legs).  A well-camouflaged ambush bug snagged it as it visited the flower. 

SOLDIER BEETLE – These guys drive the BugLady crazy.  They’re lightning beetle mimics, and they’re pretty good at it, and she always overthinks the ID.  She doesn’t know why they’re imitating the closely-related lightning beetles – alarmed lightning beetles discharge poisonous blood/hemolymph from their leg joints, but alarmed soldier beetles do, too. 

CRAB SPIDER –This Goldenrod crab spider tucked itself down between the milkweed flowers and ambushed an Odontomyia soldier fly https://bugguide.net/node/view/417289/bgimage.

LARGE MILKWEED BUG – What a beauty!  Large milkweed bugs are seed bugs – they feed by poking their beaklike mouthparts through the shell of a milkweed pod and sucking nutrients from the seeds.  They don’t harm the plant (just the seed crop), and they don’t harm monarch caterpillars, either.  Like other milkweed feeders, they sport aposematic (warning) colors to inform predators of their unpalatability.  Large milkweed bugs don’t like northern winters and are migratory – like monarchs, the shortening day lengths, the lowering angle of the sun, and increasingly tough milkweed leaves signal that it’s time to go, and they travel south to find fresher greens.  Their descendants head north in spring.

MONARCH CATERPILLAR – Common milkweed and Swamp milkweed are Monarch butterflies’ top picks for egg laying. 

GREAT-SPANGLED FRITILLARY – The other big, orange butterfly.  Adults enjoy milkweeds and a variety of other wildflowers, and their caterpillars feed on violets – if they’re lucky enough to connect with some.  Females lay eggs in fall, near, but not necessarily on, violets, and the caterpillars emerge soon afterward.  They drink water but they don’t eat; they aestivate through winter in the leaf litter and awake in spring to look for their emerging host plants.

GIANT SWALLOWTAIL – A southern butterfly that seems to be getting a foothold in Wisconsin.  The book says they are annual migrants that produce a generation here in summer and that their caterpillars can’t tolerate Wisconsin winters, but the BugLady has seen very fresh-looking Giant Swallowtails here in May that didn’t look like they had just been on a long flight.  Their caterpillars are called Orange Dogs in the South, because their host plants are in the Rue/Citrus family Rutaceae.  In this neck of the woods, females lay their eggs on Prickly ash, a small shrub that’s the northernmost member of that family. 

CINNAMON CLEARWING MOTH – A nectar-sipper but, since it doesn’t land, not a serious pollinator.

NORTHERN PAPER WASP – Butterflies love Swamp Milkweed, and so do wasps.  The Northern paper wasp is the social wasp that makes a smallish (usually fewer than 200 inhabitants) open-celled, down-facing, stemmed nest https://bugguide.net/node/view/1411890/bgimage.  “Northern” is a misnomer – they’re found from Canada through Texas and from the Atlantic well into the Great Plains.  Her super power is chewing on cellulose material, mixing it with saliva, and creating paper pulp.  She may be on the swamp milkweed to get pollen and nectar for herself or to collect small invertebrates to feed to the colony’s larvae.  Curious about Northern paper wasps?  See https://bugeric.blogspot.com/2010/09/wasp-wednesday-northern-paper-wasp.html.

Also seen were ants, leafcutter bees, sweat bees, Great black wasps, Great golden digger wasps, Red soldier beetles, Fiery and Broad-winged Skipper butterflies, and Thick-headed flies.  

Kate Redmond, The BugLady

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

Bug o’the Week – Bugs at the End of Summer

Bug o’the Week
by Kate Redmond

Bug o’the Week Bugs at the End of Summer

Howdy, BugFans,

The Autumnal Equinox is fast upon us, alas, and even though it was a very hot one, the BugLady would like to push that Restart button and go back to the beginning of August.  Failing that, here are some of the bugs that crossed her trail in the second half of summer.

BARK LOUSE – Bark lice (order (Psocidae) are often seen in herds, both as adults and nymphs https://bugguide.net/node/view/1716157/bgimage.  This species, Cerastipsocus venosus, is known collectively as Tree cattle.  Bugguide.net says that they feed on “accumulations of fungi, algae, lichen, dead bark and other materials that occur on tree trunks and large limbs.”  And on the BugLady’s porch rails.  So, they clean up after the BugLady outside, and the silverfish take care of the inside of her cottage. 

YELLOW-HORNED FLOWER LONG-HORNED BEETLE – The YHFLHB (Strangalia luteicornis) is in the Longhorned beetle family Cerambycidae and the subfamily Lepturinae, the flower longhorns.  Flower longhorns are often found on flowers by day, feeding on the protein-rich pollen, and many (but not all) species are wedge-shaped – sometimes dramatically so.  Their larvae feed on dead and dying woody material, and certain fungi that they ingest as part of their meal then aids the grub’s ability to digest cellulose (in some species of flower longhorns, Mom inoculates the eggshell as she lays it with a yeast that becomes part of the grub’s intestinal microflora). 

AMBUSH BUG – What would summer be without the extraordinarily-well-camouflaged (and voracious) ambush bugs – one of the BugLady’s favorites? 

LEAF-FOOTED BUG – Late summer is True bug season (remember – only one insect order, the Hemiptera, can officially be called Bugs).  This particular bug is the almost-grown nymph of a leaf-footed bug called Acanthocephala terminalis (no common name).  Newly-hatched nymphs, with their spiny butts and improbable antennae, are pretty cute https://bugguide.net/node/view/933082/bgimage

SPIDER WEB AND PREY – All wrapped up and nowhere to go.   

BALD-FACED HORNET – The BugLady corresponded this summer with a man who was stung twice in his mouth by a Bald-faced hornet (now called Bald-faced aerial yellowjacket).  These are the gals that build the closed, football-shaped, paper nests that hang in trees, and while they are valiant/dangerous in defense of their homes, they don’t defend the flower tops where they feed.  The BugLady’s correspondent was apparently walking along blamelessly when his open mouth encountered a flying hornet.  Stings on the face, and especially in the mouth, can be dangerous because of swelling, even if you’re not allergic. 

An entomologist named Schmidt went around deliberately getting stung by the ants, hornets, bees, and wasps of the world and writing descriptions of his discomfort that are sometimes reminiscent of a wine-tasting.  He rated the Bald-faced hornet at a 2 out of 4 on his pain scale – “rich, hearty, slightly crunchy.  Similar to getting your hand mashed in a revolving door” https://reliantpest.com/north-american-schmidt-sting-index/.  Not surprisingly, lots of exterminator companies have posted the scale because they want to sell us something.   

COMMON WOOD NYMPH – A medium/large Satyr butterfly of sunny fields, Common Wood Nymphs are not often seen nectaring on flowers, preferring fungi and rotting fruit.  They lay their eggs on grasses in late summer, but when the caterpillars hatch, they go into hibernation immediately, without feeding, to continue their development the following spring. 

CANDY-STRIPED LEAFHOPPER – what glorious things sometimes come in ¼” packages!  And, they have superpowers!  Leafhoppers suck plant juices.  Most plant sap has a sugar concentration of only a few percent, so leafhoppers have to consume a lot of it to get enough calories, and they excrete the excess (honeydew) “under pressure” with a tiny, but sometimes-audible, “pop.”  Because of this, they’re called “sharpshooters.”  And – they vocalize, but too softly for us to hear.

BROWN WASP MANTIDFLY – Yes, those poised, mantis-like front legs are used to grab smaller insects (mantidflies also sip nectar); and yes, this mantidfly does look like a paper wasp at first glance (but – no stinger).  Scroll down to see how this very flexible species has evolved to imitate different species of wasps in different parts of the country (the mantidfly is on the left) https://bugguide.net/node/view/4825

Their stalked eggs are attached to leaves https://bugguide.net/node/view/216544/bgimage, and when the eggs hatch, each larva waits for a passing spider, hitches a ride (feeding on the spider like a tick), and eventually infiltrates the spider’s egg sac, where it spends the rest of its larval life eating spider eggs.

WHITE-FACED MEADOWHAWK – You rarely see this species in tandem flights out over the water or ovipositing into shallow water.  They often “speculate” – bobbing up and down in damp areas by a pond’s edge, with the female lobbing her eggs onto the ground.  The plan is that spring rains will wash the eggs into the water. 

RED-SPOTTED PURPLE – What a classy butterfly!  Three Fun Facts about Red-spotted Purples: 1) the red is on the underside of the wings https://bugguide.net/node/view/557370; 2) though they are “tailless,” they are mimicking Pipe-vine Swallowtails, which are poisonous https://bugguide.net/node/view/2264557/bgimage; and 3) partly-grown caterpillars spend the winter inside a leaf that they’ve rolled into a tube and fastened to a twig, and they emerge and resume eating the following year (scroll down for a picture of a hibernaculum and for a bonus lesson about “frass spars” https://entnemdept.ufl.edu/creatures/bfly/red-spotted_purple.htm).  Within their leafy tube, they drop about 1/3 of the water weight in their body in order to avoid cell damage from freezing.

CRAB SPIDER – Nothing to see here, folks, just move along.

GREEN STINK BUG – Another common sight in late summer, along with their flashy, almost-grown nymphs https://bugguide.net/node/view/885566.  Some stink bugs are carnivores, and some are herbivores, and some of the herbivores are considered crop pests.  They aren’t chewers, they suck plant juices with mouths like drinking straws, which can deform fruits and seeds, damage twigs, and wither leaves.  Green Stink bugs (Pentatoma hilaris) (hilaris means “lively or cheerful”) feed on a large variety of plants (they’re “polyphagous”).  Newly-hatched green stinkbugs aren’t green https://bugguide.net/node/view/127137/bgimage.

TIGER SWALLOWTAIL CATERPILLAR – No – those aren’t eyes.  They’re pigment spots that are designed to fool you into thinking it’s a snake.  Young Tiger Swallowtail caterpillars start out as bird poop mimics https://bugguide.net/node/view/1883543/bgimage, but midway through their development, they go into snake mode, completing the effect by everting, when they feel threatened, a two-pronged, soft, orange, odorous projection (the osmeterium) that looks like a snake’s forked tongue https://bugguide.net/node/view/2214191/bgimage.  Tiger Swallowtails have two generations per year.  Caterpillars of the butterflies we see in June don’t spend long in the chrysalis, emerging in mid-August and getting to work on the next generation.  This caterpillar will overwinter as a chrysalis.  Don’t tell the other insects, but Tiger Swallowtails are the BugLady’s favorites.

As she visited her usual haunts this summer, the BugLady was dismayed at the lack of insects.  Sure, the goldenrods are full of flies, bees and wasps of various stripes, and the grasshoppers and tree crickets are singing their September songs.  But she saw six Tiger Swallowtails this summer.  Total.  And maybe a dozen meadowhawks.  During one mid-summer Dragonfly count years ago, the BugLady simply stopped counting meadowhawks when she got to 250 because it was distracting her from the other species.  Common Wood Nymphs used to emerge in early July by the score to filter through the grasses.  Even crab spiders and ambush bugs seemed scarce this year. 

What good are insects?  Sometimes it’s hard to drum up sympathy for a group that many people routinely swat, stomp, spray, or zap.  But insects provide food for birds and for other insects; they’re pollinators, and they provide other ecosystem services including pest control and garbage pick-up. 

(And, of course, they’re awesome.)

Kate Redmond, The BugLady

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

Bug o’the Week – Midsummer Memories by Kate Redmond

Bug o’the Week
by Kate Redmond

Bug o’the Week Midsummer Memories

Howdy, BugFans,

Last year the BugLady had so many midsummer stories to tell that she wrote one episode about dragonflies, and a second about “other” (because as seasoned BugFans know (well) her camera gravitates to dragons and damsels).  She’s got a heap of pictures to share again this year, but she’ll mix and match the groups in a two-part summer feature.

ROSE CHAFER BEETLE – The BugLady saw a single Rose Chafer last year and wrote about it https://uwm.edu/field-station/rose-chafer-beetle/.  This year, she found bunches of them – orgies of them (she’s not sure what the collective noun for Rose Chafers is, but she’s pretty sure it’s “orgy”).  And she was enthralled by the leggy designs they made on the undersides of milkweed leaves.  

COPPER BUTTERFLY – A highlight of the BugLady’s recent explorations of Kohler-Andrae State Park was finding two species of Copper butterflies – American Copper and Bronze Copper (she rarely finds Coppers).  The Coppers are in the Gossamer-wing butterfly family Lycaenidae, along with the Harvesters, Hairstreaks, Elfins, and Blues.  Their caterpillars feed on plants in the rose and buckwheat families (dock, sorrel, and knotweed).

VIOLET/VARIABLE DANCER – The BugLady was talking to a friend recently about the colors that dragonflies and damselflies come in.  Black, black and yellow, green, blue – even red.  But purple?

FLY ON PITCHER PLANT – This is just the way it’s supposed to work.  Insects with a “sweet tooth” get lured to the lip of the pitcher plant and partake of the (slightly narcotic) nectar there.  Judgment impaired, they mosey around a little, maybe venturing onto the zone of down-pointing teeth below the lip, and then onto the slick, waxy zone below that.  It’s all downhill from there.

GOLDENROD CRAB SPIDER on yarrow (not all Goldenrod crab spiders have red racing stripes).  Incoming insects have trouble seeing her, too.  Out of all the species of crab spiders in the world (about 3,000), only a very few have the ability to change colors, and that ability is limited to the female of the species.  Her color palette includes white, yellow, and pale green.  She sees the background color with her eyes, and because a wardrobe change takes her between three days and three weeks she tends to stay on her chosen flower.  Her base color is white, and switching involves either creating yellow pigment or reabsorbing and then sequestering or excreting it.  

Why?  Good question.  Scientists have tested spiders on matching and non-matching flowers (which they often sit on), and they saw no boost in hunting success when the spiders matched their background (she likes prey that’s bigger than she is, like bumblebees, because she has eggs to make.  She loses weight on a diet of small flies).  When spiders themselves are the prey, they are not picked off more often on non-matching flowers.  Maybe the color change gives her some sort of advantage when she forms her egg case, or maybe it’s a vestigial solution to a long-ago problem.

ORANGE-LEGGED DRONE FLY – This Syrphid/Flower/Hover fly is so serious about its bumble bee disguise that it makes a loud buzz when it’s flying

SEDGE SPRITE TUSSLE – the BugLady was in a bog not long ago when she saw two damselflies tussling on some leaves.  At first, she thought there was some predation going on, but that didn’t make sense because they were both Sedge Sprites.  He had grabbed her and was wrestling with her, and she was having none of it.  He suddenly flipped her around and clasped the back of her head with the tip of his abdomen (SOP for mating dragonflies and damselflies).  Rather than reaching forward and taking his sperm packet, she ultimately gave a couple of good shakes and dislodged him.  One small drama.

PHANTOM CRANE FLY – Flies come in all sizes and shapes, but this magical creature in white spats is the BugLady’s favorite.  It lives in dappled, brushy wetland edges where it flickers through the vegetation like a tiny wraith.

FORKTAIL AND POWDERED DANCER – Eastern Forktails are voracious hunters that go after other damselflies, even those close to their size.  The mature female forktail (in blue) found a teneral (young) Powdered Dancer (in tan) that was probably not a strong flyer yet.

Go outside – look at bugs,

Kate Redmond, The BugLady

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

Bug o’the Week – Coral Hairstreak Butterfly
by Kate Redmond

Bug o’the Week by Kate Redmond

Coral Hairstreak Butterfly

Howdy, BugFans,

Hairstreaks (and Blues and Coppers and Harvesters) are members of the Gossamer-winged butterfly family Lycaenidae (“Gossamer-winged” being a nod to the iridescent sheen on the wings of many family members).  Numbering nearly 5,000 mostly tropical species worldwide – 30% of butterfly species – Lycaenidae is the second-largest butterfly family (the Brush-foots outnumber them).  The BugLady associates hairstreak butterflies with butterfly weed and hot, sunny prairie days.

Family members share characteristics like indented eyes, striped antennae, a narrow face, reduced forelegs (males more than females), bright colors, and (frequently) hair-like “tails” on the edge of the hind wing.  The tails are often located near a blue-pigmented “eyespot” on the wing – hairstreaks often land head-down, and the eyes and antenna-like tails are said to present a predator with a “false head.”  The tails are fragile and can be worn off or may be bitten off by a misdirected predator (better to lose a chunk of a wing than your actual head). 

With the exception of the carnivorous Harvester larvae, the slug-like Lycaenid caterpillars are herbivores; adult Lycaenids feed at flowers and also get nutrients from damp mud, decaying fruit, and carrion.  Caterpillars of many species of Gossamer-wings are myrmecophiles – they have friendly relationships with ants, trading food for protection.  Caterpillars of some species are able to communicate with or summon their ants by producing vibrations that travel through the substrate.  

CORAL HAIRSTREAKS (Satyrium titus) aren’t gaudy, but they’re still pretty spiffy little butterflies.  They are hairstreaks without hairstreaks, and they don’t have blue eyespots on the edge of their wings, either https://bugguide.net/node/view/23133 (compare it to the similar Acadian Hairstreak, which has both https://bugguide.net/node/view/1490067/bgpage).  Coral Hairstreaks close their wings immediately upon landing, so the BugLady couldn’t find any picture of the dorsal side of their wings other than this pinned specimen https://digitalatlas.cose.isu.edu/bio/insects/butrfly/famlyc/satif.htm.  They have a wingspread of 1” to 1 ½”, and males and females look alike except that the male’s wings are somewhat more triangular in shape.  Here are more pictures https://www.marylandbiodiversity.com/view/513

Coral Hairstreaks are found across much of North America https://bugguide.net/node/view/4115/data.  They need two habitats, with adults visiting (and pollinating) flowers, especially butterfly weed, in open areas like grasslands, roadsides, clearings, pastures, and gardens; and caterpillars feeding on the new leaves, flowers, and even the new fruit of Black cherry and a few of its close relatives in young woods and around woodland edges.  Some hairstreak species are woodland-dwellers, but maturing woodlands become less attractive to Coral Hairstreaks, and land use practices affect their numbers. 

Aggressive males perch on vegetation and chase females and other insect intruders, and they court using pheromones (smells) and visual displays.  Females lay eggs on twigs, at the base of a host tree or in nearby leaf litter, leaving a scent mark to indicate to other females that the spot has been taken.  The eggs overwinter, hatching in spring as the new vegetation erupts https://bugguide.net/node/view/1683166/bgimage.  There’s one generation per year.

Although Coral Hairstreaks fly fast and erratically, most don’t disperse very far away from where they hatched.  On cool mornings, they warm up by sitting with wings closed, at right angles to the sun (lateral basking).  

According to the great University of Michigan Biokids website http://www.biokids.umich.edu/critters/Lycaenidae/, lacewings and ladybug beetles eat hairstreak eggs; ants, wasps, and the larvae of parasitic flies eat the caterpillars; mice and shrews feed on the pupae; and mantises, spiders, birds, frogs, and toads stalk the adults.  If they can connect with the proper species of ant, the caterpillars will be protected by them in return for allowing the ants to harvest drops of honeydew that caterpillars produce in a “honey gland” (dorsal nectary organ) http://www.pbase.com/spjaffe/image/125237720).  Caterpillars feed at night, attended by ants, and rest in the leaf litter below the cherry tree by day. 

Data from the marvelous Butterflies of Massachusetts website (https://www.butterfliesofmassachusetts.net/index.htm), where they have crunched the numbers for 150 years’ worth of butterfly sightings, suggest that warming temperatures due to climate change are causing Coral Hairstreaks there to begin their flight period two weeks ahead of the historical dates – at the beginning of July rather than the middle of July (and this is undoubtedly happening elsewhere).

Kate Redmond, The BugLady

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

Bug o’the Week – The Twelve Bugs of Christmas 2022

Bug o’the Week

The Twelve Bugs of Christmas 2022

Greetings of the Season, BugFans,

Wow!  The 10th annual installment of The Twelve (or Thirteen) Bugs of Christmas!  The Bugs of Christmas features shots, taken throughout the year, of insects and spiders who have already had their own BOTW, but who posed nicely.

The next two paragraphs were borrowed from Christmas 2016, because the BugLady is still amazed by the history of this ubiquitous Holiday Classic.

The Twelve Days of Christmas” is an English carol that was probably borrowed from the French and that was originally an acapella chant/call-and-response/children’s memory game.  There’s an alternative explanation about the various lords, rings, etc. being Christian code words for catechism during a time of religious repression (which seems a bit like playing Beatles songs backwards).  It first appeared in writing in 1780, and there were (and still are) many variations of it, though the words were more-or-less standardized when an official melody was finally written for it in 1909 (and the insect verse was, alas, dropped.  “Thirteen Bugs a’ buzzing”).

See https://en.wikipedia.org/wiki/The_Twelve_Days_of_Christmas_(song) so you can hold your own in Holiday Trivia at parties (I’ll take Christmas Songs for $300, Alex).  With apologies to all those Lords a’ Leaping, it’s time once again to celebrate a year of bugs with this baker’s dozen collection of the beautiful, the odd, and the mysterious.  Gifts.  Right under our noses.  All the time.

POTTER WASP – Throughout this BOTW series, we have noted the many places where insects deposit their eggs – in plant stems, in underwater vegetation, in dead trees, in flower buds, in mushrooms, in the BugLady’s wind chimes, in carcasses, in holes and tunnels underground, in other insects, in cells made of wax or paper, in egg sacs.  The BugLady’s favorite is the small, mud pot attached to a twig or leaf by a potter wasp. 

SEDGE SPRITE – The BugLady is a tall person, and Sedge Sprites (her favorite damselflies) are tiny damselflies, barely an inch long, that mostly fly at altitudes lower than her knees.  Photographing one involves tracking an insect the size of a sewing needle through sedges and other boggy vegetation.  What a beauty!

BUMBLE BEE – The plant is called Common Hound’s-tongue (Cynoglossum officinale) (aka houndstooth, dog’s tongue, Gypsy flower, and Rats and Mice (because it’s said to smell like them).  Lots of small flowers on a plant that may grow 4 feet tall.  It’s from Europe; it probably came over in the 19th century in a bag of agricultural seed, and it’s considered a noxious weed in parts of North America (but it’s rare in Ireland).  It contains chemicals (alkaloids) that are toxic to livestock, its bristly seeds are not wholesome to ingest, and they irritate the skin, too.  Historically, it was used as a cure for madness and to treat inflammatory diseases, lung issues, and “it heals all manner of wounds and punctures, and those foul ulcers that arise by the French pox’” (Culpeper’s Complete Herbal).

The bumble bee doesn’t know any of that, and doesn’t care.

LADYBUG and SHINING FLOWER BEETLE – Multicolored Asian Ladybird Beetles come in a variety of shades of red and orange with spots ranging from zero to many, but you can tell them by the “W” or “M” on the thorax (depending on whether they’re walking toward you or away from you).  Adults eat aphids and scale insects, and their larvae eat even more aphids and scale insects, and some eggs of butterflies and moths.  The BugLady couldn’t find anything that suggested that they might chow down on a small beetle like this Shining flower beetle, but the ladybug sure was interested in it and followed it all around the surface of the leaf.

GIANT ICHNEUMON WASPS are among the BugLady’s favorite insects (Why?  See https://uwm.edu/field-station/giant-ichneumon-wasp/).  There are two species of rust and yellow Giant Ichneumons around here https://bugguide.net/node/view/1701906/bgimage, plus Black Giant Ichneumonid Wasp https://bugguide.net/node/view/1742321/bgimage.  This is a male Black Giant Ichneumonid Wasp.  

SPIDER WEB – an abandoned trap web, toward the end of summer.

DARNER EXUVIA – In today’s usage, the empty, shed skin of an insect or spider is (mostly-but-not-always) called an exuvia (Pl. exuviae), from the Latin for “things stripped, drawn, or pulled from the body”.  The BugLady, who likes etymology as well as entomology, wanted to find out more about the word, so down the rabbit hole she went.  She discovered that even her two favorite dragonfly and damselfly books don’t agree with each other. 

The British use “exuvium” for the singular and “exuvia” or “exuviums” for the plural.  When she did a bit more delving into “exuvium,” the BugLady found this awesome excerpt from a letter written by Sir Thomas Browne to his son Thomas, dated May 29, 1679: “I have sent you, by Mrs. Peirce, a skinne of the palme of a woemans hand, cast of at the end of a fever, or in the declination thereof; I called it exuvium palmæ muliebris, the Latin word being exuvia in the plurall, butt I named it exuvium, or exuvia in the singular number.  It is neat and is worthy to be showne when you speake of the skinne. …. A palmister might read a lecture on it.” 

A post in a bugguide.net discussion further muddies the waters by stating that the cast-off skin of an insect should be referred to in the plural (exuviae) because “a single cast skin is a collection of insect parts and is thus an exuviae.” 

There’s no logical equivalent in Classical Latin, but Scientific Latin takes liberties with the Classical.  The entomology community tacitly agrees that it’s a “we-know-it’s-not-correct-but-we’re doing-it-anyway” situation. 

The snail had nothing to do with the emerging dragonfly and, the BugLady guesses, is passing by.

BUMBLE FLOWER BEETLES – When the BugLady found some of these and wrote about them one fall https://uwm.edu/field-station/bumble-flower-beetle/, BugFan Chris told her that they’re also around in the spring.  Sure enough – she spotted this one in mid-May. 

MOURNING CLOAKS aren’t splashy, and they eschew wildflowers in favor of dripping sap, but they’re pretty spiffy nonetheless, and they’ve got a cool life story.  In a group (the order Lepidoptera) where the adult portion of a lifespan is usually measured in a few, short months, these are long-lived and complicated butterflies.  They overwinter as adults, mate, and lay eggs in spring.  Their offspring feed on willow leaves, form chrysalises, and emerge as adults in late spring or early summer.  After feeding for a while, they go into a state of aestivation (summer dormancy) to avoid wear and tear.  They wake in fall, feed some more, and then overwinter as adults in a state of suspended animation called diapause, which is similar to hibernation, tucked up in a cloistered spot called a hibernaculum that shelters them from the elements, and protected from the effects of freezing by glycerol (antifreeze) in their bodies.  They may fly during a January thaw or on mild days in late winter, but they can reenter diapause when the temperature drops.  When they emerge and mate in spring, they’re about 10 months old. 

This pretty CLICK BEETLE by the name of Ampedus sanguinipennis (sanguinipennis means “blood wing”) is found in wooded areas – its larvae develop in, feed on, and then pupate in very rotten wood, emerging as adults by fall, but hunkering down within the pupal cell for the winter.  Adults are pollen feeders that shelter under loose bark.  Somewhere in its travels, this beetle encountered some mites, which hitched a ride.  The harmless transporting of other organisms is called phoresy.  Here’s a glamour shot https://bugguide.net/node/view/20063.

If you’re a CRAB SPIDER and you don’t spin trap webs, you need a different strategy for finding dinner.  Crab spiders employ camouflage and ambush.  The flower is a tallgrass prairie plant called leadplant. 

COMMON GREEN STINKBUGS (Chinavia hilaris) are considered persona non grata in agricultural fields and orchards because both the nymphs and the adults feed on fruit and developing seeds.  And yet.  Hilaris means “lively” and “cheerful,” and that’s the vibe this stink bug was sending on a sunny day.

And an EASTERN AMBERWING Dragonfly in a pear tree. 

Kate Redmond, The BugLady

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

Bug o’the Week – Bugs at the End of Summer

Bug o’the Week

Bugs at the End of Summer

Howdy, BugFans,

The general rule of thumb is that if you want to find insects, look at flowers.  Even though summer is fading, there are still flowers in bloom.  Some Liatris/blazing stars linger, along with brown-eyed Susan, wild sunflowers, asters and goldenrod (more than a century ago, Asa Gray said that the 12 pages about goldenrods in his Manual of the Botany of the Northern United States, from New England to Wisconsin and South to Ohio and Pennsylvania Inclusive (aka Gray’s Manual) were the most uninteresting in the Manual).  Late summer and early fall are dominated by flies, bees and wasps, and by grasshoppers, katydids, and crickets.

Most adult insects die by the first frosts, leaving behind the next generation in the form of eggs or pupae (occasionally as nymphs or larvae), so the clock is starting to tick pretty loudly.  As BugFan Mary stated dispassionately many years ago, they’re dead and they don’t know it yet.  Meanwhile, their activities are centered on eating and on producing the next generation.

AMBUSH BUG (pictured above) – One of the BugLady’s favorite insects is the ambush bug (she’s always had a soft spot in her heart for predators).  Ambush bugs tuck themselves down into the middle of a flower and wait for pollinators.  They grasp their prey with their strong front legs, inject a meat tenderizer, and slurp out the softened innards.  They’re paired up these days (the BugLady has a picture of a stack of three), and she has several pictures where the female is multitasking – eating an insect while mating.

BUMBLE BEE – A bumble bee forages for nectar and pollen for the brood well into September, but the brood will not survive the winter.  Only the newly-fertilized queens will see the spring and establish a new colony.  Moral of the story – plant Liatris/Blazing star.

PUNCTURED TIGER BEETLES (aka Sidewalk or Backroad Tiger Beetles) are named for the rows of pits on their very-slightly-iridescent elytra (hard wing coverings).  They’re common across the continent in dry, sandy, bare spots, and as one of their names suggests, they’re sometimes seen on sidewalks.  Like their (much) larger namesakes, Tiger beetles chase their prey https://bugguide.net/node/view/1106590/bgimage.  For more info http://www.naturenorth.com/Tiger%20Beetle/The%20Tiger%20Beetles%20of%20Manitoba.pdf.  

Some Punctured tiger beetles are “plain” https://bugguide.net/node/view/1343674/bgimage, and some are “fancy” https://bugguide.net/node/view/223895, and some are green https://bugguide.net/node/view/2025474/bgimage.  

FAMILIAR BLUETS signal the end of the damselfly season.  Big, robust, and startlingly-blue, they’re one of the BugLady’s favorite bluets.  

EASTERN COMMA – There are two generations/broods/”flights” of Commas (and Question Marks – the “anglewings”) each year.  The second generation overwinters as adults, tucked up into a sheltered spot (a hibernaculum).  They sometimes emerge during a January thaw, but they quickly resume their winter’s sleep.  They fly briefly in spring – one of our early butterflies – and produce the summer brood.

FALL FIELD CRICKET – Poking her ovipositor into the soil and planting the next generation.  Her eggs will hatch in spring, and her omnivorous offspring will eat leaves, fruits, grain, and other invertebrates. 

The BugLady loves their simple songs http://songsofinsects.com/crickets/spring-and-fall-field-crickets and is happy when a cricket finds its way indoors in fall.  Males form a resonating chamber by setting their wings at a certain angle; then they rub their wings together to produce sound (one wing has a scraper edge and the other has teeth).  There are mathematical formulae for calculating the ambient air temperature based on cricket chirps that give you the temperature in the microclimate on the ground where the cricket is chirping (add the number of chirps by a single field cricket in 15 seconds to 40). 

CANADA DARNER – Common Green Darners are robust dragonflies that fill the late summer skies with dramatic feeding and migratory swarms.  There are other darners, though, primarily the non-migratory mosaic darners (like the Canada, Green-striped, Lance-tipped, and Shadow Darners) whose abdomens have blue and black, “tile-like” patterns.  Identify them by the shape of the colored stripe on the thorax and by the shape of the male’s claspers (lest you think it’s too easy, females come in a number of color morphs – this is a green-form female Canada Darner).  

MONARCH BUTTERFLIES were alarmingly scarce this summer – the short-lived Gen 3 and Gen 4, whose job it is to build the population in the run-up up to the migratory Gen 5, simply weren’t there.  But, on one of the BugLady’s recent stints on the hawk tower, she saw 289 Monarchs heading south during a six-hour watch.  Moral – Plant goldenrod (and native milkweeds).

GOLDENROD CRAB SPIDER – Like ambush bugs, crab spiders live on a diet of pollinators.  They don’t build trap nets and wait for their prey to come to them, they pursue it.  Sometimes they lurk on the underside of the flower, but their camouflage makes hiding unnecessary.  This female looks like she’s sitting at the dinner table.

RED-LEGGED GRASSHOPPERS are very common in sunny grasslands at this time of year from coast to coast.  They eat lots of different kinds of plants (including some agricultural crops, which does not endear them to farmers), but they prefer plants in the Legume/pea family and the Composite/aster family.  As the air temperature increases – and when predators are around – they eat more carbs.  Grasshoppers are food for spiders, many birds, and other wildlife.  Moral of the story – plant wild sunflowers.

PAINTER LADY – You don’t get to be the most widespread butterfly in the world (found everywhere except Antarctica and South America) by being a picky eater.  It migrates north in spring – sometimes in large numbers and sometimes in small.

THIN-LEGGED WOLF SPIDER – This Thin-legged wolf spider formed an egg sac (with about 50 eggs inside), attached it to her spinnerets and is going about her business.  When the eggs hatch, her young will climb up on her abdomen and ride around piggyback for a few weeks before dismounting and going about their lives. 

GREAT BLACK WASP and GREAT GOLDEN DIGGER WASP – Two impressive (1 ¼” long) wasps grace the flower tops at the end of summer.  Both are good pollinators, both are solitary species that eat pollen and nectar, and both dig tunnels and provision chambers with paralyzed insects for their eventual offspring.  Great Black Wasps https://uwm.edu/field-station/great-black-wasp/ select crickets and grasshoppers for their young’s’ pantry, and so do Great Golden digger wasps https://uwm.edu/field-station/great-golden-digger-wasp-family-sphecidae/.  Neither is aggressive.  

The moral of the story?  Plant lemon horsemint.

Kate Redmond, The BugLady

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

Bug o’the Week – Mid-summer Scenes

Bug o’the Week

Mid-summer Scenes

Greetings, BugFans,

Summer has reached its half-way point, and the BugLady has been recording the changing of the guard.  The adult lives of most insects are brief – four to six weeks for many, and considerably less for some.  Bluet damselflies are fading, but meadowhawk dragonflies are taking the stage.  Little Wood Satyr butterflies are hard to find, but Common wood nymphs now flit through the fields.  You get the picture.  Here are some bugs that the BugLady found in the first half of summer.

ARROW CLUBTAIL:  In early July, the BugLady came across this just-emerged dragonfly sitting on a stalk in the Milwaukee River.  She photographed it for half an hour as it lengthened and strengthened and spread its wings and grew its abdomen.  She guarded it from marauding geese and grackles.  And she watched as it took its maiden voyage, eight feet straight up and true – into the beak of a swooping Cedar Waxwing.  She may have used a few bad words. 

JAPANESE BEETLE   Precarious as this bundle of beetles looked, it kept its shape as it fell off and into the grasses.  In order to jump-start her love life, a female Japanese beetle may use “come hither” pheromones, but this aggregation of beetles was probably initiated (inadvertently) by the plant itself.  Research suggests that a female Japanese beetle chewed on a leaf, and the leaf gave off signature chemicals (OK – feeding-induced plant volatiles), and that instead of repelling the beetles, the scent attracted more beetles, both male and female, to feed.  And, since all those guys and gals are in the same neighborhood……… 

MAYFLY MOLT:  BugFan Freda sent this amazing “What-is-it?” picture recently, taken from a canoe on the Milwaukee river.  Mayflies (called “lake flies” regionally) emerge from their watery cradles by the googol.  Their lives are brief, averaging only three days (not coincidentally, the name of the mayfly order is Ephemeroptera).    

Mayflies are the only insects that shed their skins after they reach the winged adult stage (silverfish shed as adults, too, but they’re spindle-shaped and wingless).  The mature mayfly naiad https://bugguide.net/node/view/517056/bgimage crawls out onto a plant or rock and sheds its final skin (exuvia), emerging as a form called a subimago (or a “dun” if you’re a fly fisherman) that is cloudy-winged, dull in color, weak-flying, and not ready to reproduce.  The sub-imago rests (often overnight) and then sheds again, this time into a mature adult/imago with shiny wings (a “spinner” to fishermen).  Here’s a typical adult/imago https://bugguide.net/node/view/933725/bgimage.  No – scientists do not know how this pre-adult stage benefits the mayflies – lots of insect groups apparently has a subimago stage in ancient times, and most have dropped it from their repertory. 

Freda’s picture shows the exuviae of lots of sub-imagoes – it must have been an amazing sight to see!  Scroll down this series of pictures of that final shed – http://www.troutnut.com/article/10/pictures-of-mayfly-dun-molting-to-spinner.  

DOGBANE LEAF BEETLE:  Its fabulous, shimmering exterior is all done with mirrors (complex nanoarchitecture).  Light is bent when it hits small, randomly-tilted plates that sit between the pigment layer and the top layer of the beetle’s cuticle, and the beetle’s color changes depending on the angle of the eye of the beholder.  What good is that glow?  Rather than being an aid in courtship or a warning of the beetle’s toxicity (and this particular beetle is, but not all iridescent insects are), this fiery iridescence actually camouflages it.  To test the hypothesis, researchers disguised meal worms with beetle elytra (the hard outer wings) – some shiny and some not – and then hid them.  Birds found and ate 85% of the “dull-winged meal worms,” but only 60% of the “iridescent meal worms,” and the scientists themselves found it difficult to locate the shiny ones. 

STREAM BLUET AND MAYFLY: In order to make it to adulthood, a mayfly naiad must avoid being eaten by fish and a variety of insects during its aquatic stage, and by fish, birds, fishing spiders, frogs, and other predators as it completes both of its molts.  When it takes to the air, more predators await.  This mayfly became lunch for a Stream Bluet damselfly.  

DOODLEBUG:  The BugLady found this doodlebug on the dunes at Kohler-Andrae State Park in mid-July, plying its trade.  She looked into lots of inverted, sandy cones before she found one that held prey – in this case, a small spider.  The doodlebug will grow up to be an antlion https://bugguide.net/node/view/1708468/bgimage.  For an account of the life of a doodlebug, see https://uwm.edu/field-station/spotless-antlion/.  

SAWFLY:  Sawflies are not flies, but are primitive wasps with no stingers (as she did when she wrote her first episode about sawflies in 2009 https://uwm.edu/field-station/sawfly/, the BugLady recommends reading the sawfly chapter in David W. Stokes’ excellent A Guide to Observing Insect Lives).  Sawfly larvae look a lot like butterfly and moth caterpillars, but there’s a difference in the arrangement and types of legs.  This beauty just might be the Poison ivy sawfly (Arge humeralis), whose pretty cute offspring the BugLady is going to have to keep a cautious eye out for https://bugguide.net/node/view/826616/bgimage.  “Sawfly” because the female uses a saw-like structure at the end of her abdomen to cut slots in vegetation to lay her eggs in.

BLACK SWALLOWTAIL CATERPILLAR: While the BugLady was photographing the sawfly, she noticed a prickly head among the Queen Anne’s lace florets, so she bent the stem sideways to see what it was.  There was a cute little jumping spider under there, too, which she hoped did not have designs on the caterpillar.  Black Swallowtails lay their eggs on plants in the carrot family, and most gardeners who plant dill are familiar with them (and, the BugLady hopes, are generous enough to share). 

BLUE MUD DAUBERS are all over the Queen Anne’s lace these days.  Adults cruise the flower tops, sipping nectar and looking for spiders to cache in the egg chambers of their offspring, who will grow up on protein but eschew it as adults.  Sometimes the wasps pick spiders right off of their webs, and they especially like to collect Black widow spiders (which are here in God’s Country but are rare https://bugguide.net/node/view/1876965/bgimage).  They grab spiders with their mandibles https://bugguide.net/node/view/1268654/bgimage and paralyze them with a sting, but they don’t bite people, and you have to rough one up considerably before she’ll sting you.

EMERALD ASH BORER:  The BugLady loves ash trees, but these days, the landscape is littered with their skeletons.  The first Emerald ash borer was detected in Wisconsin in Ozaukee County during the summer of 2008, though the EABs had undoubtedly been around for a few years before that.  The picture shows an ash that is fighting for its life, a battle that it will not win.  The top of this ash is dead, because the EAB larvae’s tunnels (galleries) just below the bark interfere with the flow of nutrients between the crown of the tree and its roots.  The stressed tree responds by growing a bunch of shoots (called epicormic sprouts) from dormant buds in the bark of the trunk.  The leafy sprouts, which are below the EAB damage, will allow the tree to photosynthesize – for a while.  Read about EABs in a previous BOTW.https://uwm.edu/field-station/emerald-ash-borer-redux-family-buprestidae/.  EABs are, undeniably, beautiful beetles https://bugguide.net/node/view/1770902/bgimagehttps://bugguide.net/node/view/1233730/bgimagehttps://bugguide.net/node/view/938332/bgimage

SIX-SPOTTED FISHING SPIDER:  Moving from a “solid” water lily leaf to a liquid substrate is no trick at all for a Six-spotted Fishing spider (the six spots that give it its name are on its underside) – in fact, it has more moves on the water than it does on dry land.  It can walk, run, sail, or skate over the surface film and can dive under it, too. 

GIANT SWALLOWTAIL: If there’s anything more stunning than a couple of Giant Swallowtails dancing in the air over purple coneflowers, the BugLady doesn’t know what it is. 

Kate Redmond, The BugLady

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

Bug o’the Week – Cuckoo Leafcutter Bee

Bug o’the Week

Mid-summer Scenes

Greetings, BugFans,

Summer has reached its half-way point, and the BugLady has been recording the changing of the guard.  The adult lives of most insects are brief – four to six weeks for many, and considerably less for some.  Bluet damselflies are fading, but meadowhawk dragonflies are taking the stage.  Little Wood Satyr butterflies are hard to find, but Common wood nymphs now flit through the fields.  You get the picture.  Here are some bugs that the BugLady found in the first half of summer.

Within the Megachilidae, the tribe Megachilini contains the genus Coelioxys – the Cuckoo leaf-cutter bees, aka the Sharp-tailed bees (Coelia means “belly” and “oxys” means “sharp”).  The Coelioxys aren’t the only bees that are “cuckoos,” a term that refers to bees that lay their eggs in another bee’s nest; Rusty Burlew, on the Honey Bee Suite website, tells us that 20% of all bee species are nest parasites (another source put it at 15%) and that this behavior occurs in most bee families (which means, he says, that there’s “a whole lot of poaching going on”).  

The host bees aren’t just babysitting.  Cuckoo bees are “kleptoparasites” (kleptoparasitism means “parasitism by theft”).  Their offspring take advantage of the work of the nest-building/host female, eating the food stores she has collected and killing their rightful owner.  There are 46 species in the genus Coelioxys, and each species targets different species of bees, mostly from within their own Megachilidae family.  

Because they no longer make nests for their young (one website suggests that they’ve been nest parasites for so long that they’ve forgotten how), they are minimally-hairy (oddly, they have hairs on their eyes), and they lack the dense, pollen-collecting hairs under the abdomen that many leaf-cutting bees sport https://bugguide.net/node/view/30569/bgimage.  For that reason, they’re not good pollinators.   

One website says that “Cuckoo leafcutter species appear very similar to the casual observer, and species identification is often best left to an expert,” and the BugLady plans to take that advice (for a change).  Females have pointy abdomens https://bugguide.net/node/view/1593995/bgimage, and males’ abdomens are toothed https://bugguide.net/node/view/2050487/bgimage.  Most of our northern species are basic black with white lines, sometimes with red in the legs, but some Southern species are fancier – https://bugguide.net/node/view/1616384/bgimagehttps://bugguide.net/node/view/2093977/bgimagehttps://bugguide.net/node/view/1409086/bgimage.  Most are less than a half-inch long.   

Female Cuckoo bees are bee-watchers; they visit flowers to sip nectar, but also to spy on potential hosts and follow them back to their tunnels.  When its owner leaves, looking for more pollen, the cuckoo bee enters the tunnel and uses the sharp tip of her abdomen (a modified stinger) to puncture the leafy walls of an egg chamber and to lay her eggs inside.  Her larva will use its sickle-shaped jaws to bisect the host egg or larva, and it will kill any of its own siblings in the chamber.  It pupates in the egg chamber, and its emergence the following year will be synched with the flight period of its host.

Fun Facts about Cuckoo Leafcutter bees:

  • The genus name is pronounced “seal-ee-OX-ees.”

FOR THE RECORD: to every author out there who likened the actions of cuckoo bees to cuckoo birds (family Cuculidae), a clarification.  New World species of cuckoos (except for three species in South America) build their own nests and care for their own young; some (but not all) Old World members of the cuckoo family (the 56 members of the subfamily Cuculinae, the Parasitic cuckoos) are, famously, brood parasites.  The difference between a nest parasite and a brood parasite is that brood parasites, like our Brown-headed Cowbird, leave their eggs in other birds’ nests with the expectation that the adoptive parents will raise their young.  This often comes at the expense of the nest-maker’s brood, since the cowbirds hatch first, grow fast, monopolize the feedings, and may elbow the other chicks out of the nest. 

Kate Redmond, The BugLady

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

BREAKING NEWS: in another fit of Political Correctness, the Entomological Society of America has renamed the Asian giant hornet, aka the Murder hornet, (a hornet that is, indeed, from Asia) “in an effort to reduce negative and nationalistic associations.”  It’s now the Northern Giant Hornet.  The BugLady supposes that the Asian multicolored ladybug will be next, but as BugFan Mike suggests, maybe the Negro bug https://bugguide.net/node/view/5184, nominally in the Ebony bug family, should come first.  

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