Bug o’the Week – Lightning Beetle Again and Again

Bug o’the Week
by Kate Redmond

Lightning Beetle Again and Again

Greetings, BugFans,

2025 – The BugLady has been seeing her first firefly around the 4th of July.  She stands on the riprap, enjoying the fireworks shows launched by her neighbors and the more distant municipal displays while the fireflies fly around her, putting on their own, equally magical shows.

Fireflies are one of the BugLady’s “nemesis groups” – they refuse to be in focus when she photographs them.  Like sowbug/roly-poly/pill bug/woodlouse, your choice of lightning beetle/bug or firefly is a regional thing.

Enjoy this rerun – a few new words (because who can resist rewriting?) and new pictures.  Genus IDs are tentative.

2018   OK – this is a love story of sorts.  It’s an episode that originated in 2009, and it has already been rerun once and now rewritten again.  But…..the BugLady just returned from southern Ohio, where she co-led a workshop about Bugs and Wonder (Wonder – an unappreciated, sometimes suspect, and insufficiently-entertained state of mind) (and mostly we could say that about the bugs, too).  We trawled the prairies and woods for bugs during the day, and at dusk and into the night, we hunted for fireflies. 

Do you call them lightning bugs or fireflies?  Carl Linnaeus coined the latter term in 1767.  The more arid, western parts of North America are either “firefly-lite” or their fireflies are day-flying and therefore “mute,” as evidenced by the lack of names for them.

Lightning bugs float silently (but brilliantly) over the dark fields, woods, and wetlands of June and July, inspiring poets and children of all ages.  They are neither flies nor true bugs; they are members of the Order Coleoptera and the family Lampyridae and are more correctly called Lightning beetles.  And yes, their ethereal light show is all about sex. 

Their path to the skies starts in late summer of the previous year.  Mid-summer eggs hatch into carnivorous larvae that eat insects, snails, and other small critters (the BugLady thinks that the larvae look like tiny pangolins).  They like damp conditions (remember –a thatch of grasses, especially tall grasses, creates a microclimate that’s generally moister than the air five feet above it), and there are even a few species whose larvae are aquatic. 

They overwinter as larvae, buried in the soil, and when spring comes, they wake up and keep on eating (the natural history of firefly larvae needs more study).  They pupate in early summer, also in the earth, before emerging for their brief-but-dazzling stint as adults. 

Larvae subdue their much larger prey by injecting a paralyzing fluid, and they are considered important controls on snails and slugs.  According to the Field Guide to Insects of North America, the larvae of the common genus Photinus are subterranean and “may hunt earthworms in packs.”  The diet of adults varies by species – there are carnivores, omnivores, and non-eaters.

Most threats to their populations tend to be man-made – wetland loss, pesticides, light pollution that dims their displays, paving, and mowing (many adults, after all, are resting in the grass, waiting for sundown and setting lawn mowers at “scalp” cuts down fireflies, too).  Populations of some species are shrinking, and more eyes are needed.  For some Firefly Citizen/Community Science projects, see https://www.xerces.org/endangered-species/fireflies/community-science.   

Light production is an uncommon talent in insects.  There are semitropical click beetles that can (some of these, called cucujos, are worn as luminous decorations by partygoers south of the border, and their eggs and larvae also glow).  Luminescence is achieved by others (including some springtails) (try to imagine a springtail, glowing green except for its antennae and legs https://www.facebook.com/groups/AllBugsGoToKevin/posts/did-you-know-some-springtails-can-glow-di-was-chatting-with-some-people-in-the-c/1896815764507530/) because they harbor photogenic bacteria (here meaning that the bacteria are light-generating, not that they are picturesque, though the BugLady thinks they are both). 

Firefly light is a “cold” light.  An incandescent light bulb is an inefficient energy-user, wasting 90% of its energy as heat.  Less than 8% (some say less than 3%) of the energy that a lightning beetle expends on light is lost as heat.  Light is produced at the south end of the abdomen, in a photogenic layer that is located beneath a white, reflecting layer.  Chemical energy is converted to light energy by the action of an enzyme called luciferase on a chemical called luciferin (history buffs please note: some old friction matches were called Lucifers). 

Day-flying members of the Lampyridae like the Black firefly or Woodland Lucy (Lucidota atra) don’t glow – producing light would be a waste of energy for a diurnal insect.  All lightning beetle larvae, some pupae, and even some eggs also glow, for reasons that are not fully understood.  But lightning beetles don’t just gleam, they produce controlled flashes of light – strobes, aerial “J’s,” three-second horizontal dashes, and more.  The various species of fireflies divide the landscape by altitude, habitat, light color and intensity, time of evening, and duration of flight.  Each species has its own particular “Morse Code,” though male and female “codes” may be different. 

lucidota

Males signal from the air, and females, which in some species are wingless, respond from on or near the ground (females and luminescent larvae are called glowworms).  The signals continue until they find each other and romance ensues.  Females of some species of lightning beetles resume flashing after mating, adopting the code of a different species.  If she is successful in luring a male, this femme fatale will eat him (she, it seems, does eat as an adult!); this practice is called “aggressive mimicry,” but females generally do not eat males of their own species.

Lightning beetle family members have poisonous blood (they ooze toxic droplets from the base of the wing covers).  Besides being an invitation to party, their light is probably also an advertisement to predators that the firefly is toxic (though apparently better-tolerated by some than by others) https://www.youtube.com/watch?v=auxfhO2-ABI.  In Discovering Nature at Sundown, a good source of lightning beetle information, Elizabeth Lawlor relates that a frog that eats enough LBs may glow temporarily but seems otherwise unaffected. 

Since this episode originally appeared, the BugLady has become increasingly aware of (and confused by) firefly look-alikes in the form of soldier beetles https://bugguide.net/node/view/478212/bgimage.  Some net-winged beetles and click beetles are also mimics – BugFan Mary emailed the BugLady about a firefly on her window screen that had two lights in the front of its body – turned out to be a click beetle (https://bugguide.net/node/view/126741/bgimage), a far Southern specialty.  Most lightning beetles have a shield-shaped thorax that covers most or all of their head, and a bunch of soldier beetles also have a widened and colorful thoracic shield, though a soldier beetle’s head may protrude from under the shield significantly more than a firefly’s.  Every time she looks into this matter, the BugLady ends up relabeling a few pictures.  For other glowy insects, see https://www.firefly.org/bioluminescent-insects.html#:~:text=It%20glows%2C%20but%20it%20isn,however%20have%20glowing%20abdominal%20segments.

Accounts abound of certain species of lightning beetles in Southeast Asia that gather by the thousands on specific trees.  As dark falls, they begin to blink – first randomly, and then in complete synchronicity, illuminating the trees for hours.  The cast reassembles nightly for months to produce a spectacular light show.  Do you have to buy a steamer ticket to witness a similar spectacle?  You do not – synchronous firefly displays occur in the Appalachians, but you’ll need to enter a lottery to see them https://smokymountains.com/park/things-to-do/synchronous-fireflies-smoky-mountains/.  Here are two similar but different videos: https://www.wbir.com/article/news/local/predicting-synchronous-fireflies-peak-in-the-great-smoky-mountains-a-gamble/51-561422926 and https://www.youtube.com/watch?v=QCWkzQqO7Ro.

Just out is a book by Lynn Frierson Faust.  In Fireflies, Glow-worms, and Lightning Bugs, she offers descriptions, ranges, photos, flash patterns, habitats, and terrific common names, names like the Woodland Lucy, Little gray, Big dipper, and Chinese lantern.

At the other end of this love story is (shameless plug) the Arc of Appalachia, the organization that ran the Wonder Workshop, an organization that has been buying and providing stewardship for chunks of prairie, gorge and rich eastern forest, with its old growth beech and maple, sycamore, tulip tree, sassafras, and gum.  Find their story at http://arcofappalachia.org/

The Lightning Beetle is a poster child for why the BugLady loves BOTW – the research begins innocently enough, and then WHAM!  Cucujos!  Glowing eggs!  Glowing frogs!  Glowing trees!  Poisonous blood!  Ravenous packs of LB larvae!  Luciferase! 

Excellent!

Kate Redmond, The BugLady

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

Bug o’the Week – The Mighty Mosquito rerun

Bug o’the Week
by Kate Redmond

The Mighty Mosquito rerun

Howdy, BugFans,

2025 – almost two decades ago, when the BugLady was working on a phenology project in the Bog, she encountered multitudes of mosquitoes and she made a deal with them – she wouldn’t bite them if they wouldn’t bite her.  Sometimes it works, sometimes it doesn’t, and sometimes she is in the presence of someone who is far more tender and juicy than she is.  She’s leading a field trip at the Bog soon, and she’ll find out if everyone remembers the deal.

Mosquitoes have been discussed in a number of BOTWs – https://riveredgenaturecenter.org/bug-othe-week-floodwater-mosquito-an-homage/ and

https://uwm.edu/field-station/bug-of-the-week/psorophora-ciliata-aka-the-shaggy-legged-gallinipper/ – this is the first (with a few new words and pictures).

And remember – bug zappers don’t kill mosquitoes.  The New York Times Wirecutter section says, “Bug zappers kill bugs by the thousands. But there’s a problem: They kill the wrong bugs. They are ineffective against mosquitoes and other biting flies, and their otherwise indiscriminate killing can disrupt pollination and generally throw the environment out of balance. Plus, the force of their electrocution can spew a mist of disease-ridden bug parts out into the air.”

2014 – Who hasn’t seen the postcard (and keychain and license plate holder and t-shirt and coffee mug) that trumpets the mosquito as our state bird?  It’s the insect we all love to hate (they are the very definition of the word “swarm”), but behind the legend lies a fascinating animal.

Yes, there are a lot of them – about 3,500 species worldwide, 175 in North America, and 50 in Wisconsin.  Mosquitoes (mosquito is Spanish for “small fly.”) are in the Order Diptera (“two wings”) and they are in the family Culicidae.  Some people think they’re kind of pretty (including the BugLady, when she’s not inhaling them). 

Yes, they grow up fast.  Eggs are laid on the surface of the water, on floating leaves, or in a spot just above the water line that will subsequently flood.  They generally hatch in a few days, and it takes about month to morph from egg through larva (called a “wiggler”/”wriggler”) (because twitching is their mode of locomotion) through pupa (“tumbler”) (because their mode of locomotion is tumbling) to adult, but in some species, development is telescoped into 10 days.  Mosquitoes don’t live very long – males for about a week and females for two or three.  Depending on species and location, there can be several generations per year. 

Some species of mosquito overwinter as fertilized females in sheltered spots (or in basements, which explains why the BugLady sees the odd mosquito flying around her house in January), and they’re raring to go when spring comes.  Other species may overwinter in a state of delayed development called diapause in any of the above stages, resuming growth when the water warms in spring. 

Yes, they are adaptable.  Eggs develop in wetlands but also in birdbaths, puddles, pails, flower pots, old tires, and the dog’s outside water dish (if you put water in it, they will come).  The first line of defense in knocking down residential mosquito populations is getting rid of these man-made sources of standing water. 

Yes, they do bite.  Females mate only once, but they may lay several “clutches” of eggs.  Males, newly emerged females, and non-egg-laying females feed on nectar and other plant juices, but before each cluster of eggs that she lays, a female must ingest a (high-protein) blood meal (in some species, the blood-letting starts with the second batch of eggs).  Some mosquitoes include humans on their list of possible donors; others restrict themselves to birds, reptiles, amphibians, or non-human mammals. 

She injects, with her saliva, small doses of anticoagulant and anesthetic to aid the process (the resulting red, itchy bump is caused by your body’s histamine reaction to the injected proteins).  Then she ingests so much blood that taking off seems impossible.  A mosquito’s abdomen has expandable tissue between each segment and also between the harder upper and lower surfaces of each segment, so it stretches both vertically and horizontally. 

The BugLady once found a decent-sized snapping turtle digging a hole to lay her eggs in at dusk and, of course, got as close as she could to get some pictures without disturbing the process.  She was AGHAST when she put the pictures up on the monitor and saw that the soft (but still armored) parts of the poor turtle were covered by tiny mosquitoes, and that they were even on her shell.  And that the grass around the turtle’s head was littered with mosquitoes that were too bloated to fly! 

Most mosquito wigglers eat the algae, bacteria, debris, and zooplankton that’s floating around in the water with them.  Some species are predators, and a few even eat the larvae of other mosquitoes.  Wigglers are important food chain “middlemen” between the tiny organisms they feed on and the fish, amphibians, reptiles, birds and the other aquatic insects that prey on them.  Adult mosquitoes are an essential food for bats, birds, dragonflies and damselflies. 

Yes – Female mosquitoes of some species are notorious transmitters of diseases caused by various viruses, protozoans, and nematode worms (the warmer winters we’re having due to Global Climate Change are allowing some tropical diseases like dengue fever to move north again as the mosquitoes that carry them extend their range).  These causative agents generally set up shop in the mosquitoes’ salivary glands, which ensures a free ride into the blood donor’s body (Remember to give your dog it’s heartworm medication). 

More fun facts about mosquitoes:

  • That annoying hum is actually a love song.  He sings alto, and she sings tenor, and when they hear each other (they sense sound with their antennae, and the male’s antennae are quite fancy) (some males have big, hairy palps -sensory adjuncts to the mouthparts – too), they vary their tone – by changing the frequency of their wing beats – until both are humming at the same pitch.  Romance ensues.
  • Some species of mosquitoes prefer to lay their eggs in the seclusion of a small pool of water that is trapped in a plant; these reservoirs are called phytotelmata (“phyto” means plant and “telma” means pond) (the singular is phytotelma).  A specialized bog species, the harmless pitcher plant mosquito (Wyeomyia smithii) grows only in the water of the purple pitcher plant (Sarracenia purpurea).  Tropical species of Wyeomyia develop in bromeliad “tanks.”  Holes in trees where rainwater collects are a common kind of phytotelma.
  • Wyeomyia smithii turns out to be a pretty interesting critter. Its eggs are deposited in the new leaves of pitcher plants.  The larvae/wigglers are considered top predators in the community of organisms that inhabits the pitcher plant’s water reservoir.  They feed on bacteria and mini-animals in the pitcher plant’s water, and while they do eat some of the bits of partly decomposed insects that were meant to nurture the pitcher plant, they feed on organisms that feed on bacteria, ensuring a diverse crop of bacteria to decompose the insects that fall into the pitcher plant’s water.  They overwinter in the pitcher as larvae, frozen in its water.  For a thorough biography of the PPM, see http://animaldiversity.ummz.umich.edu/accounts/Wyeomyia_smithii/.
  • There’s even a mosquito that helps with mosquito control.  Elephant/treehole mosquitoes in the genus Toxorhynchites are big, primarily tropical, mosquitoes.  According to bugguide.net, one species, Toxorhynchites rutilus https://bugguide.net/node/view/2168964/bgimage, ranges from Connecticut to Florida to Texas to Kansas.  Turn them loose, especially in a manmade water tank, and they will feed on the wigglers of other species (and of their own), and they do not require a blood meal.  Everything one might want in a mosquito! 

And yes, for reasons that are not completely clear, mosquitoes are more attracted to some people than to others.  A lot of scientific experiments have been done and anecdotal explanations offered (an individual’s general “sweetness” of temperment is apparently not a factor).  It may be a response to clothing color (they prefer dark), perfumes (love ‘em!), blood type (they prefer Type O), pregnancy (yes), body heat, particularly aromatic sweat, and/or distinctive carbon dioxide exhalations.  Ms. Mosquito can detect CO2 in the air from 25 yards away and home in on the source. 

And by the way, the BugLady would like to suggest that whoever keeps writing “Mosquitoes are crepuscular – active at dawn and dusk – and they rest during the heat of the day” has only visited God’s country in the snow. 

Kate Redmond, The BugLady

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

Bug o’the Week – June Beetle redux

Bug o’the Week
by Kate Redmond

June Beetle redux

Greetings, BugFans,

2025 – One of the BugLady’s daughters gave her a subscription to Storyworth for her birthday, so she has been working her way through weekly questions.  It’s sobering to realize that she and her sisters are the Keepers of the Family Lore.  Anyway, a recent question asked if she believed in magic, and, if yes, what examples could she give?  The BugLady finds magic everywhere – in sandhill cranes bugling far overhead, in the raucous chorus of a thousand spring peepers, in the icebergs that float by her cottage, in a cloud of Monarchs rising from a clump of goldenrod, in Tiger Swallowtails, Luna Moths, phantom crane flies – you get the picture.

Years ago, she was leading a Woodcock and Frog Walk on an unseasonably warm evening at the end of April, and as the group stood at the edge of the field in the dark, listening to the sky dance of a Woodcock, we could hear the sound of June bugs emerging from the ground and flying away.  Magic.

2014 – June bug clarification:  a number of different genera of beetles in various regions of America are also popularly called June bugs/May beetles.  Some are green https://bugguide.net/node/view/2304753/bgimage and some are striped https://bugguide.net/node/view/1266419, but most are gray/brown/rust-colored.  There’s even a conspicuous on-line image of a Japanese beetle, genus Popillia, labeled as a June beetle, and one exterminator website displays a picture of a beautiful Dogbane leaf beetle (possibly the most beautiful beetle ever https://bugguide.net/node/view/2317088/bgimage) with a June beetle caption.  Caveat emptor.  OUR June bugs, in the genus Phyllophaga, are the real ones.  Just sayin.’

So, today we will consider one of the BugLady’s favorite beetles, and not for the last time, revisit the word “bug.”  The June “bug” is not a True Bug.  True Bugs are in the order Hemiptera (“half-wings”) (because in the original order Hemiptera – not the new, improved, “lumped” order that combines Hemiptera and Homoptera – Hemipterans characteristically had forewings that were leathery on the proximal half, with the membranous distal half folded underneath.  Beetles (the order Coleoptera – “sheath wings”), have two pairs of wings.  The hardened front pair, called the elytra, cover and protect two membranous hind wings that are used for flying.  In flight, the elytra are held out to the side, which causes beetles to look like tiny bi-planes and to fly and land awkwardly.  After a beetle lands, its flying wings don’t always get tucked in neatly. 

If JBs are “clumsy;” they are also described as sticky-legged and “clingy.”  They love grabbing screens, and they will hold onto clothing with their long, gangly legs (in a totally non-menacing way, of course).  When JBs fall off the BugLady’s door and land on their backs, they spin around, glaring up at her, struggling to right themselves. 

JBs are members of the Scarab family (Scarabaeidae), renowned by ancient Egyptians.  Scarabs, no matter what their species or size or shape or color, have small, flat plates at the tips of their antennae https://bugguide.net/node/view/1840844/bgimage that they can open like a fan.  June beetles have three plates, which are held at right angles to the antenna.  There are roughly 400 members of the genus Phyllophaga north of Mexico, and many species cannot be distinguished without looking at their “naughty bits.” 

When they are not eating leaves, the nocturnal June beetles come to lights.  They are a group that carries on its affairs in darkness – in fact, Wikipedia cryptically states that adults die after being exposed to the light for too long.  A number of years ago, the local June beetle population boomed, and the sounds of June bugs as they flew into and fed in the trees at night was loud enough to be mistaken for a breeze rustling the leaves.  June bugs spend the day sheltered under the ground (or in the woven, front door mat) without tearing their flying wings, thanks to those elytra.  They emerge after sunset over a period of several hours; yet at dawn, the whole population disappears within ten minutes.  A June bug got into the BugLady’s house one night, and the cats found it the next day in the rug, burrowed under the foot of a chair. 

The diurnal manifestations of June beetles generally consist of individuals snagged in spider webs by the porch light (the BugLady can’t help but admire the pluck of these small spiders), or as high-fiber elytra, discarded on the ground, evidence of someone’s midnight snack. 

According to the excellent A Guide to Observing Insect Lives by Donald Stokes, the females of many species have such short wings that they are essentially flightless (so the beetle that crashes your party is probably a male).  Females attract their mates via an airborne pheromone, which gives the old “Come hither” to males within twenty yards.

A female lays 50 to 100 eggs, a few at a time, in “cells” that she excavates in the soil.  The eggs hatch soon afterward, and although some species of June beetles may live a total of three or four years, they spend most of that time as grubs.  Insects that live longer than the usual eight or nine months must make plans to survive winters, and they also have the opportunity to develop an immune system.  The June beetle overwinters as a grub, below the frost line, for its first two years and although pupates at the end of the next summer and emerges as an adult shortly afterward, it spends its third winter underground as an adult

June beetle larvae (the larvae of beetles are often called “grubs”) are known to people who grow lawns and gardens as “white grubs” (an inaccurate generic term).  They are sometimes pests of grasses and agricultural crops (the BugLady has a color slide of a June beetle grub feeding on a newly-dug potato) and will move on down a row of plants, nibbling the roots of each plant as they go.  Adults eat leaves of a variety of trees (“Phyllophaga” means “leaf eater”).

The larvae of the spectacular American Pelecinid wasp https://bugguide.net/node/view/1271561 are parasitic on some ground-dwelling beetle grubs, including June beetles.  Ms. Pelecinid bores her impressive ovipositor into the soil and deposits her eggs on her young’s larvae.  A few flies are parasitoids of the adults. 

So, to summarize: June bugs are beetles (not bugs) that often appear at the end of May (and so are sometimes called May Beetles) and can be found through part of July (but are never called July Bugs).

Kate Redmond, The BugLady

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

Bug o’the Week – Ants 101 Rerun

Bug o’the Week
by Kate Redmond

Ants 101 Rerun

Howdy, BugFans,

2025: This episode is a Golden Oldie, first/last posted in 2008.  Despite her feelings of ambivalence about ants, the BugLady continues to photograph and write about them.  See https://uwm.edu/field-station/bug-of-the-week/flying-ants/https://uwm.edu/field-station/bug-of-the-week/the-ants-of-cesa/, and https://uwm.edu/field-station/bug-of-the-week/western-thatch-ant/, and more.  For this rerun, the BugLady added a bunch of random pictures of ants being ants.

The BugLady was out on the trail with a bunch of 3rd graders one day, and they found an ant hill – a small, conical mound with a hole in the center.  When she asked the kids how that pile of dirt came to be there, one speculated that ants brought dirt in from the surrounding area to protect the entrance.  Yet another reminder that we all see things from a unique angle.

11-18-08: The BugLady and the AntFamily have logged six [now seven-plus] decades of run-ins, which the ants invariably win (Lederhosen will work if you want to sit on thistles, but they won’t save you if you sit on an ant hill, and that’s the last thing the BugLady is going to say about that!).  Fire ants, which the BugLady encountered during a Texas litter pick-up, but which are not yet found in Wisconsin, will undoubtedly look her up when they get here (fire ants can run from their nest inside a discarded beer can, past the elbow of a litter-picker-upper’s arm at warp speed, biting and stinging all the way up, and that’s the last thing the BugLady is going to say about that, too!).  The BugLady does, however, admit to standing out in the hot, east Texas sun, enthralled with the solemn, single-file processions of leaf-cutter ants snaking around the edge of a parking lot. 

Like bees, wasps, horntails and sawflies, ants are in the order Hymenoptera (“membranous wings”).  Hymenopterans have been around for about 200 million years, and ants, which developed from wasps, for about 90 million years, give or take. They are most numerous and diverse in the tropics.  Elizabeth Lawlor, in Discover Nature around the House, (an excellent series) says that E.O. Wilson found 43 species of ants living in a single tree in Peru (which is more than the total number of species in Great Britain), and that only three species live in the Arctic above the treeline.  They are considered by some to be at the pinnacle of insect evolution and to be the most numerous of all insects (and, it is said, if all the world’s humans sat on one side of a cosmic teeter-totter and all the ants sat on the other, the humans’ feet would be dangling).  There is a HUGE amount of information available about ants, and what follows is only a quick overview.

Although many hymenopterans are solitary, the order is famous for housing the social insects, and all/nearly all species in the ant family are social.  Most colonies operate with a caste system that includes a queen (a fertile female that mates only once and then retires to lay eggs, read romance novels and eat chocolates for the rest of her life, which may span up to 15 years), workers (sterile, wingless females who care for the queen, eggs, and larvae, maintain and defend the colony, and forage for food), and males.  Nuptial flights in spring and fall mark the only time ants may be winged (and then, only the Royal ants); after mating the male dies, and the young queen bites/scrapes off her wings and starts her own anthill.  She cares for the first crop of workers, feeding them saliva and eggs, until (Moms take note) they get old enough to care for her forevermore. 

Nests are generally (but not exclusively) excavated in the ground or in rotting trees, and some ants take advantage of the solar-heated microclimate that exists under a rock.  Other (larger) ant mounds are created when ants bring in materials from the surrounding area, forming a slightly domed mound and then tunnel through it – the domed shape facilitates heat absorption, and the temperature inside may be 15 to 20 degrees warmer than outside. Ants are active a good part of the year; the picture of the ant on the plum blossom was taken in early May and the group shot on the orange, in early November. In the winter, ants can migrate vertically, and live below the frost line.

Each nest/colony/hive has an individual scent, a combination of chemical secretions and of the scent of the colony’s nesting material; this allows its members to identify their sisters at home or away.  These chemicals also, according to Lawlor, “cause the workers to respond and maintain cooperative and altruistic behavior.”  When workers meet, they feel each other with their antennae and then feed each other a bit of food, which strengthens the bond of the colony.  Foraging ants may find their way to a food source and then back home by following both a chemical/pheromone trail (rubbing your finger across a chemical trail causes the ants temporary confusion) or by visual landmarks, and an ant deposited off-trail is in trouble.  Each segment of an ant’s antennae has a different sensory task; read Lawlor. 

In T.H. White’s terrific Arthurian tale, The Once and Future King, young Arthur’s lessons include being turned by Merlin into a variety of animals, including an ant, and the ant-lessons are powerful and memorable.

Ants enroll in a wide variety of food plans, depending on their species.  They consume nectar and other plant juices, and honeydew “milked” from herds of Homopterans like aphids and treehoppers. They gather seeds (ants disperse the seeds of many kinds of plants) and browse the oranges the BugLady puts out for the birds), and eat dead organic matter, decaying trees, and houses. Or, they may be predators, attacking small invertebrates.  Leafcutter ants mix pieces of leaf with their feces and make a garden in which they culture fungi to eat.  Stokes, in A Guide to Observing Insect Lives, has an interesting write-up of how a group of ants cooperates to carry home a large piece of food. 

Despite their familiar presence on flowers, they are poor pollinators, because of their slippery exoskeletons and fastidious grooming habits.

Some species of ants can bite, and some species sting – the ovipositor, which workers don’t use anyhow, has been modified into a stinger – and some do both.  Some also produce and spray formic acid or other chemicals, which act as irritants. 

The BugLady met an instructor who claimed to be a connoisseur of ants.  He said that black ants are too bland; small, red ants are too spicy, and that ants that have a red head and thorax and a black abdomen (like the (possibly) Allegheny mound ant pictured here farming the tiny treehopper nymphs) are just right.  Native Americans in the desert southwest collected honey ants and used them as sweeteners, and ant larvae and pupae provide protein for humans in parts of the world.  Ants are also eaten by birds, reptiles, amphibians, mammals, fish and by other insects.

Breaking news!  An abstract in a recent “Science News” reports on a species of US ant that raids the nests of a smaller species and enslaves its young.  The slaves do the housework and care for the young of their mistress.  BUT, some slave ants have evolved a behavioral resistance to this and were pictured destroying young in the nursery (and referred to as “killer nannies”).  AND – this drama is playing out in the nest of the larger queen – IN AN ACORN!!!

Go out and watch some ants (but always know where your extremities are).

Kate Redmond, The BugLady

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

Bug o’the Week – Deer Tick again

Bug o’the Week
by Kate Redmond

Deer Tick again

Howdy, BugFans,

2025:  The BugLady was out in a wetland today, stalking the wily Pink Lady’s Slipper (aka the Moccasin flower), a large and lovely native orchid.  After she got home, she discovered a male Wood/Dog tick on her person (dark, with pale streaks), so it seemed like an auspicious time to rerun the episode about the Deer tick.

2014: The BugLady encountered a deer tick on her scalp last week (second week of March), a reminder that these are very hardy little critters – AND – that the uncharacteristically balmy weather is getting lots of stuff going early.  So, here’s the deer tick story as told in a BOTW from three years ago along with some hot-off-the-presses additional information and, of course, new pictures.

The DEER TICK (Ixodes scapularis) (not to be confused with the musical group Deer Tick) is a critter whose escapades are well known to those of us who live here in God’s Country (at least they should be).  It’s notorious for its ability to spread Lyme (not Lymes) disease and because its sesame-seed-size makes “tick checks” a challenge (scroll down to the ruler at http://www.entnemdept.ufl.edu/creatures/urban/medical/deer_tick.htm). 

Lyme disease is an initially-flu-like disease that doesn’t go away and will escalate if ignored, and it is more treatable early than late.  The CDC has a very comprehensive website with information about tests, symptoms, treatment, and prevention at http://www.cdc.gov/lyme/, (there’s disagreement about Lyme disease testing and treatment, mainly from organizations whose members have spent months and years looking for a clear diagnosis and an effective cure for this frustrating disease).  Lyme disease is not “catching,” and you can’t get it from eating venison from an infected deer (but kneeling on the ground dressing out a deer puts you right down there in DT territory). 

When the BugLady moved into her rural home 39 years ago, ticks were scarce, she plucked a wood/dog tick (Dermacentor variabilis) off the dog every 5 years or so, and she never saw a deer tick.  In the past four or five years she has seen fewer wood ticks, but deer ticks (a.k.a. Black-legged ticks) have arrived in force and are showing their little heads by late April (chiggers are way more numerous, too).  An article in Science Daily (June 22, 2011) refers to the “steady march of deer ticks across the Upper Midwest” and reports that the rate of their advance through Indiana and Illinois (having successfully occupied Minnesota and Wisconsin) is two counties per year. 

Non-feeding adult DTs are very small (about 3mm long) and flat and dark (females may look blood-red when they’re empty but not when they’re full, and males are dark and vaguely speckled). They have eight black legs and a black “shield” (called a “scutum”) in back of its head.  DTs don’t have any white/light markings on the scutum, but wood ticks do.  A feeding adult female looks like a tiny, over-filled, blue-gray balloon (“as tight as a tick”) (the BugLady is trying to avoid comparisons to grapes here, lest she put BugFans off their feed). 

DTs lead a complex, three-stage, two-year life.  All three stages are mobile and all three require a blood meal that can take three to five days to complete.  Adult DTs are fairly impervious to frosts and can be out and about on winter days that are above freezing.  In spring, Mom has a big meal (adult males rarely feed), mates, drops to the ground, and lays thousands of eggs.  The first post-egg stage is a minute’ six-legged larva that feeds once during mid-summer on a bird or a small mammal (it’s especially fond of white-footed mice).  The well-fed larva leaves its host and overwinters in the leaf litter.  The following spring it molts into a poppy seed-sized nymph that feeds again (another mouse, maybe, or a raccoon or squirrel) and then molts into an adult that becomes active in fall.  Adults favor large mammals like white-tailed deer. 

Ms. DT finds Mr. DT through the magic of aggregation pheromones (chemical “perfumes”) that cause DTs to gather in groups, allowing boy to meet girl.  They may mate on a host, on vegetation, or on the ground.  He dies after mating a few times; she dies after laying eggs. 

Where does a DT pick up Lyme disease?  Typically not from Mom, even if she’s carrying it.  An uninfected larva or nymph can pick up the disease from its host; an infected larva can transmit it to its host, and once they’ve picked up the infection, ticks retain it for the rest of their lives.  The general estimate is that in high-Lyme areas, 25% of nymphal DTs and 50% of adults carry the bacterium that causes the disease, but according to the American Lyme Foundation, fewer than 5% of DTs south of Maryland are carriers.  Dog ticks do not spread Lyme disease (but they are not totally innocent bystanders, either). 

DTs are classed as sanguivores (animals that ingest fresh blood).  They’re opportunistic – to find a host, they’ll often wait at the tips of vegetation in what is called the “questing position,” sensing the air, waiting for something large to brush against them (top picture http://blogs.scientificamerican.com/observations/new-map-shows-that-most-lyme-infected-ticks-are-in-northeast-northern-midwest/ then scroll down for a Lyme map – we no longer presume that someone who tests positive for Lyme has been “up North”).  The biggest mortality factor for ticks may be starvation, and harsh climate can also affect them.  They typically aren’t eaten by predators because they’re simply too small to see. 

Here’s the DT’s pedigree: they’re in the family Ixodidae (the hard ticks), which is in the order Ixodida (ticks), which is in the Class Arachnida (spiders and friends), which is in the Phylum Arthropoda (insects, spiders and crustaceans).  They are, potentially, found wherever their final host, the white-tailed deer, is found.  Most DTs live east of a line from Minnesota to Texas, http://www.cdc.gov/ticks/geographic_distribution.html.  

Along with Lyme disease, DTs can pack a number of disease-causing bacteria and parasites into that tiny body, and scientists are still finding new ones.  In the three years since the original DT post, a West Nile virus/meningitis-like disease called Powassan virus has been added to the deer ticks’ arsenal.  Tiny nymphal ticks far outnumber their elders, and because nymphal ticks are most active during the period when we’re all outside in summer, bites from nymphal ticks are presumed to be the cause of most human infections.  Pets can get Lyme disease, too; talk to your vet. 

Also new on the Wisconsin scene is a new tick species, the Lone Star tick, which carries its own set of unpleasant diseases, including one that may trigger in the “bitee” a lifelong allergy to beef, pork, and lamb. 

Scientists have discovered some intricate ways that DTs fit into the ecological jigsaw puzzle:

1)   In eastern oak forests, a big load of acorns (a “mast year”) results, for the next few years, in lots of white-footed mice and deer, which means fewer gypsy moths (mice eat their pupae) and more hosts for the DTs.  More DTs mean more Lyme disease.  Fewer acorns mean fewer mice, more gypsy moth outbreaks, and less Lyme disease.

2)    The incidence of Lyme disease is linked to the presence of deer, but it also reflects the population cycles of certain small mammals.  A decrease in predators like the red fox (coyotes have taken over) results in larger populations of potential tick hosts like mice and chipmunks and more Lyme disease (remember, though deer are important in the DT’s end game, most people probably get infected by a DT nymph, which hasn’t met a deer yet).

3)   DTs like white-footed mice, and white-footed mice like woodlands.  Research in Illinois shows that DTs are gaining a foothold in Illinois prairies by setting their sights on prairie voles instead.

So – stay inside until winter?  Through winter?  Nope.  Standard precautions include wearing light-colored clothing, using repellents containing DEET, and pulling socks over your pants cuffs to make it harder for ticks to duck and hide.  According to the CDC, “In most cases, the tick must be attached for 36-48 hours or more before the Lyme disease bacterium can be transmitted,” so do thorough tick checks of your hairline and all your nooks and crannies.  

…………………………………………..the BugLady feels like stuff is crawling on her……………………..

Kate Redmond, The BugLady

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

Bug o’the Week – Gone Fishin’

Bug o’the Week
by Kate Redmond

Gone Fishin’

Greetings, BugFans,

Here’s a rare glimpse into the BugLady’s “BOTW Future” file, which is packed with pictures of identified insects that she hopes have a good story to tell, with semi-identified insects, and with (mostly) her “X-Files” – the Unidentified.  (The file probably reflects the state of the BugLady’s brain.)  It’s what she sees as she selects the bug of the week.

Traditionally, the BugLady goes on sabbatical for the month of June, but she’s going to sneak away a bit early this year.  Why?  There’s an old riddle,

“Why did the glaciers retreat?”

“To get more rocks.”

 

The BugLady needs more pictures.

Lest your inbox grow cobwebs, she will post a tasteful rerun each Tuesday until she gets back.

FROM THE FILE:

BEE X23 (on bergamot)23-1 – a busy little bald bee.

BEETLE MILKWEED ANNULATUS HL22-2 – Not our common Red milkweed beetle (Tetraopes tetropthalmus).  There are two species here that are adorned with those lovely double rings on the antennal segments – T. femoratus (which has red on its legs, unless it doesn’t), and T. annulatus, sometimes called the Ringed milkweed beetle.  The BugLady would happily call this T. annulatus based on appearance and habitat (dry, sandy areas), but it was sitting on Common milkweed, which is not listed as one of annulatus’s food plants.  Is the BugLady overthinking this?  Probably.

TULE BLUET DAMSELFLY21-2 – with a bunch of water mite nymphs on its abdomen.  The BugLady knows who this is, but she’s written biographies of a number of other bluets, and the details of their life histories don’t vary a lot.  Besides, she promised that she would not march methodically through the species lists of Wisconsin dragonflies and damselflies.

So many wasps!!!

BRACONID15-22 – someday the BugLady is going to write a Braconid Wasps 101 episode (they’re a big and important family) but first she needs to figure out which of her wasp pictures are braconids, because they can look similar to Ichneumon wasps (an even bigger family).  This one seems to be ovipositing in the flower.

WASP ICHNEUMON Latholestes17-10 – maybe a braconid.

X WASP17-1 – also maybe a braconid

WASP ICHNEUMON RNC22-1 – a large and handsome Ichneumon.

WASP MISTLETOE SLB24-3 – this Ichneumon (probably) was exploring the flowers of Eastern dwarf mistletoe.

WASP FBMP OOF24-2 – an odd little wasp that joined the BugLady on the Hawk Tower on a cool day in mid-November.

X MOTH20-7 – this handsome, largish moth looks like it should be in the genus Haploa but…..

FLY DEER RNC23-2 – looks like a deer fly, but cinnamon- colored?

PLANTHOPPER NYMPH13-1 – isn’t this a little cutie!

SPIDER WAUB24-1 – what a lovely, almost translucent spider!

X LONGHORNED BEETLE HL15-2 – enjoying the wild geranium one spring day.

WEEVIL EP12-1 – Isn’t this a great little weevil?  The BugLady scooped it from the surface of an ephemeral pond, but she doubt’s that it’s an aquatic species – more likely it was sitting on a leaf and got dislodged.

See you in July,

Kate Redmond, The BugLady

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

Bug o’the Week – Running Crab Spiders

Bug o’the Week
by Kate Redmond

Running Crab Spiders

Greetings, BugFans,

Long-time BugFans know that the BugLady is infatuated with the lovely, sedentary Flower Crab spiders (family Thomisidae) that she photographs throughout the summer https://bugguide.net/node/view/5610/bgpagehttps://bugguide.net/node/view/2383290/bgimagehttps://bugguide.net/node/view/1299520/bgimage,  and she recently posted a BOTW about the chunkier Ground crab spiders https://uwm.edu/field-station/bug-of-the-week/ground-crab-spiders/ (also Thomisidae).

Running crab spiders, in a separate family (Philodromidae) have been mentioned briefly throughout the years – here’s their story.

They are “running” by both name and by inclination – they move along smartly, and Philodromidae comes from the Greek “philodromos,” meaning “lover of the race/course.”  There are 92 species of spiders in this widespread family in North America, and they’re usually found on the stems and leaves of plants.  Philodromuis and Tibellus are common genera.

These are not flashy spiders – most are small (measuring less than ½” long), flat-bodied, and drab.  Many (but not all) are crab-shaped like the Thomisids, but in Philodromids, the second pair of legs is noticeably longer than the first.  Eye arrangement is an important tool in spider ID – here’s what it looks like to stare two genera of Philodromids in the face https://gnvspiders.wordpress.com/7-philodromidae-running-crab-spiders/.

Philodromids don’t spin trap webs, but they do generate silk to make egg sacs and to form drag lines that catch them if they catapult off of a leaf in pursuit of prey or if they have to bail in order to avoid capture themselves.  They are, of course, carnivores that eat any small invertebrate that they can ambush and subdue, including other spiders, and they are small enough to become prey of larger spiders, themselves.

Most sources said that their venom (should they even be able to puncture your skin) might result in some pain and swelling, but is not considered dangerous. 

Males encounter females as they wander the landscape.  She leaves a trail in the form of a pheromone-laden silk dragline; he catches up with her and romance ensues.  She conceals her egg sac and guards it (like the female Philodromus guarding eggs that she had stashed in an empty beech nut shell) until her young hatch toward the end of summer, which markedly enhances the spiderlings chances of survival.  The almost-mature spiderlings overwinter sheltered in leaf litter and under tree bark and mature the next year.  A bitterly cold winter takes a toll on overwintering Philodromids. 

The most common Philodromid genus is PHILODROMUS, flat spiders that look similar to the Thomisid crab spiders.  There are 55 species in North America and about 200 more elsewhere.  They’re found on vegetation, but also on the ground or on walls.  Larry Weber, in Spiders of the North Woods, writes that Philodromus spiders are often found in trees (and sometimes inside the house, high on the wall), and that he has collected immature Philodromus spiders on the snow in early winter.

Philodromus spiders don’t spin a web but they may create a silken shelter.

With their cylindrical abdomens, spiders in the genus TIBELLUS (tib-EL’-us), the Slender crab spiders, are un-crab-like crab spiders.  There are seven species in North America and two (or three) in Wisconsin, and some are striped and others are not.  Based on the presence on the abdomen of both stripes and of two spots toward the end, the BugLady thinks she’s photographed Tibellus oblongus, the Oblong running spider, which has a patchwork range across North America https://bugguide.net/node/view/143110/data and is also widespread in the northern half of the Old World.  

When a male Oblong running spider encounters a female, he taps her rapidly with legs and palps, and if she’s agreeable, she remains motionless.  He spins a “bridal veil” that covers her and fixes her to the substrate.  When the show is over, he leaves (in a rush) and she releases herself from the veil.

Today’s Science Word – the Oblong running spider is referred to as an “epigeal” organism, which means that it’s found on/above the soil surface and does not tunnel, swim, or fly.  Oblong running spiders are often seen stretched out on grass leaves – the first two pairs of legs forward, the third pair hanging on, and the fourth pair extended back. 

Like other spiders, Philodromids have superpowers, and one is their ability to walk on smooth, vertical surfaces without sliding off.  How do they do it?  Scopulae (scopulas).  Alert BugFans will recall that many bees have clumps of hairs – scopa/scopae – on their legs or abdomens that allow them to collect and carry pollen.  Same root word – the Latin “scopa” means “broom,” “twig,” or “brush” but scopula is the diminutive form (mini-brush).  Scopulae are dense tufts of hairs that are found below the claws and at their tips on the feet of walking or wandering (non-web-spinning) spiders.  The ends of those hairs are further fragmented, forming many, microscopic contact points for the spider’s foot.  This creates a natural adhesion that is sometimes enhanced by liquid excreted from adhesive pads (alternately, one source suggested that the scopulae respond to a super-thin layer of water that covers most surfaces).

HEADS-UP!  CICADAS ARE COMING!! – https://www.smithsonianmag.com/smart-news/watch-for-cicadas-billions-from-brood-xiv-will-soon-emerge-after-17-years-underground-180986592/?utm_source=smithsoniandaily&utm_medium=email&utm_campaign=editorial&lctg=91269370

Kate Redmond, The BugLady

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

Bug o’the Week – Galls II – Historic Galls Redux

Bug o’the Week
by Kate Redmond

Galls II Historic Galls Redux

Greetings, BugFans,

This week’s episode is a rerun from the very early days of BOTW.

The BugLady loves it when the research she is doing makes a sharp turn toward History.

Galls are mentioned by (very) early observers like the philosopher Theophrastus (371 to 287 B.C.) whose two botany books, Enquiry into Plants and On the Causes of Plants, influenced scientific thinking for the next 1500 years.  People have been pondering the mysteries of galls for a long time, although not all of the hypotheses have been righteous ones.  For example, because they were considered “supernatural growths,” galls were used to foretell the future.  In the Middle Ages, their contents were examined (much tidier than chicken entrails).  Spiders signaled pestilence; maggots meant either famine or a plague among cattle; flies – war; and ants – a bountiful harvest.  In 1686 Malphigi suggested that galls were swellings that plants (like people) developed due to being stung by insects (but he straightened out and went on to discover capillaries and to have the Malphigian tube named after him).

Galls 101https://uwm.edu/field-station/bug-of-the-week/galls-i/, provided an introduction to the biology of galls and gall-makers.  Short version: “Better living through chemistry.”  This week’s BOTW features a few oak galls and a grape gall.  Remember, of the 2,000-plus kinds of galls found on North American plants, 800 different kinds form on oaks (genus Quercus). 

Cynipid wasps, which mainly target stems and leaves, are very big players in the oak gall game.  The galls caused by some Cynipid wasps are very high in tannin/gallotannin (giving them the bitter taste that gave rise to their name, gall).  Tannic acid is produced routinely by many plants (the plant’s strategy is to make itself unpalatable to grazers), but galls contain the highest tannin concentrations on most plants.  It has been suggested that the gall-makers enjoy some “tannin-perks;” since tannins are somewhat anti-microbial, high-tannin galls may protect the larva against fungi and bacteria.

Interesting as they are to Nature Appreciators and to Scientists (they are, after all, “tumors” and their dynamic in that area is being studied), galls have a history of human commerce and use that goes back thousands of years.  They have provided food, medicine, lamp fuel (in Greece, from a gall caused by a wasp named Cynips theophrastea), chemicals for tanning hides, dyes for fabric, leather and hair, beads for necklaces, and inks for tattooing and writing. 

Aleppo galls (produced by Cynips gallae-tinctoriae on certain Turkish/Eastern Bloc oaks) have the highest concentrations of tannin among the galls, 50 – 65%.  Historically, Aleppo galls provided a strong astringent and a treatment for fevers, burns, mouth ulcers and toothache.  They continue to be important trade item, now used more for tanning and dyeing and as an ingredient in inks. 

The presence of traces of iron-gall ink in the Dead Sea Scrolls makes for a pretty impressive pedigree.  S.W. Frost, in Insect Life and Natural History, wrote in 1942 that “in some places, the law requires that permanent records be made with ink derived from gallnuts……The Aleppo gall has been specified in formulas for inks used by the US Treasury, Bank of England, German Chancellery, and the Danish Government.”  The downside of iron-gall ink is the fact that it tends to fade after, oh, 1,500 years or so, and by that time, it may have discolored your paper, too.  Google “oak gall ink” or “iron-gall ink” for the recipe; you can join the artists who explore older media – and the forgers of old documents – in reviving this ancient ink.

Oak-Apple Gall – There are about 100 kinds of these marble-to-ping-pong-sized galls; they grow on a leaf’s mid-vein or on the leaf stem (petiole).  Some kinds have thin outer shells with fibrous insides, and others are denser.  The oak apple pictured is occupied by a single larva.  In fall, when you find these on the ground among the fallen oak leaves, check to see if there is a tiny exit hole and think about the size of the full-grown wasp that made it.  Stokes, in Nature in Winter (great section on galls), tells of opening an oak apple gall that held about 200 ant eggs along with their nursery workers, and he has also found nests of mud wasps inside.

Oak Bullet Gall – Because they form from the woody tissue of the twig, these half-inch galls are very firm and can stay on a tree for several years.  There are about 50 kinds of oak bullet galls, and some secrete a sticky “honeydew” that attracts other Hymenopterans- ants, bees and wasps.  One source said that in exchange for the honeydew, the honeydew-eaters discourage parasitic wasps from laying their eggs in the galls.  But, another source mentions attacks on bullet galls by parasitic wasps that insert their ovipositers into the gall and lay their egg on the gall-maker’s larva.  Birds may peck open the gall and go after the larva.

Woolly Oak Leaf Gall – These attach to the mid vein (usually) or side veins (sometimes) and they look like cottonballs.  They grow on the underside of the leaf, and they are easier to see as the leaves fall.  Based on this one sample, it looks like they may have a “vampire-like” effect on some surrounding tissue.

Grape Phylloxera Gall – In 1850, there was only one species of grape being grown in all the vineyards of Europe.  In about 1860, the Grape Phylloxera (a wingless aphid about 1/20” long) was accidentally introduced from its native North America.  The rest, as they say, is history.  By 1880, the little critter had traveled to Australia, Algeria, South Africa, and via a different route, California.  One-third of French wine-producing grapes, about 2 ½ million acres, were wiped out (Mother Nature usually finds a way to deal with monocultures). 

While leaf galls seldom damage a plant, a plant with grape phylloxera leaf galls has root galls, too, and the root galls weaken and stunt the vine.  The French fought back, and after burying live toads under the vines to draw out the poison failed to work (True!), they imported the rootstocks of resistant American Fox grapes both to graft the French vines onto and to develop hybrids from – all the while “dissing” the quality of the American grapes.  Each of the leaf galls may house a teeny, yellow Aphid Mom and hundreds of eggs and/or nymphs.

Despite the galls and the withering, the leaf continues to function.

And by the way, it really bugs/galls the BugLady that much of the information about these generally harmless growths is found on sites that have a pest control and forestry-pest bias.  The accounts invariably end with some variation of “These are harmless and don’t measurably damage the plant, but you don’t like the looks of them, so here are some chemicals you could throw at them.”

This concludes Galls I – How They Do That, and Galls II – A Date with History.  Coming eventually, Galls III – Oddball Galls.

Go outside – look for galls!ody in the past five days.

Kate Redmond, The BugLady

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

Bug o’the Week – A Tale of Two Mussels – Eight Years Out

Bug o’the Week
by Kate Redmond

A Tale of Two Mussels Eight Years Out

Howdy, BugFans,

The BugLady has been curious about the status of Zebra and Quagga mussels since she posted an episode about them in 2016 (“A Tale of Two Mussels – the One-Two Punch”).  Here’s the original post (slightly tweaked and clarified), with a summary of her recent search of the literature at the end.  Put your feet up and grab a beverage.

Spoiler alert – although there continue to be new articles about these mussels, many are a rehash of older information, and it’s frustrating when agencies do not date their information pages (you know who you are), so it’s hard to say if they’ve been updated.

2016 – When the BugLady started researching zebra mussels, it became apparent that the story of this non-native, invasive mussel was inextricably entwined with that of an equally-alien and equally-invasive mussel, the quagga mussel.  And also that we are, as a species, appallingly slow learners. 

Zebra and quagga mussels are in the Phylum Mollusca, a diverse bunch that includes snails and slugs, limpets, clams, scallops, squid, octopi, and cuttlefish.  Within the Mollusks, they’re in the order Bivalvia, and in the family Dreissenidae. 

Zebra mussels (Dreissena polymorpha) and Quagga mussels (Dreissena bugensis) have traveled far from their native haunts, the Caspian Sea drainage of western Russia, but they have settled nicely into their new homes in America, hitchhiking through the Great Lakes and inland lakes and rivers on boats, boots, bait buckets, and on the feet of waterfowl.  Zebra mussels were first identified in the US in 1988 in Lake St. Clair, just east of Detroit, and they reached Wisconsin by 1992.  In 2010, they were found in 130 Wisconsin lakes and rivers. 

The first North American quagga mussel was found in 1989, but it wasn’t positively identified until 1991.  The two mussels are now found in 29 states, and the National Wildlife Federation website estimates that the Great Lakes alone are home to 10 trillion (with a “T”) zebra and quagga mussels.  They are similarly-marked, but the underside of a Zebra mussel shell is flattened, and a Quagga mussel’s shell is more rounded and doesn’t lie flat.  Pictures of the two may be found at: https://www.invasivespeciescentre.ca/invasive-species/meet-the-species/fish-and-invertebrates/zebra-and-quagga-mussels/.  Here an animated map of the Zebra mussel’s spread between 1986 and 2024: https://nas.er.usgs.gov/queries/SpeciesAnimatedMap.aspx?speciesID=5 (the BugLady loves animated maps), and graphics showing the spread of both species in the Lake Michigan basin up until 2015 (scroll down to the Lake Michigan profiles) https://greatlakesecho.org/2019/05/30/invasive-mussels-challenge-commercial-whitefish-fishing-in-the-great-lakes/

Did they hoof it over here on their own?  They did not; like most of us, they came over on the boat.  They undoubtedly arrived in the Great Lakes in the ballast water of ships that ply international waters, as have a rogue’s gallery of hardy gatecrashers (more than 180 species, so far) – a number of North American organisms have been toted to Europe in the same fashion. 

Here’s the physics of it: while they’re in their home ports, European vessels take water (plus whatever is swimming in that water) into tanks built on the inside of the ship’s hull, and this “ballast water” helps keep the ship upright.  A ship carrying a small cargo needs lots of ballast, but as it loads more cargo, it discharges ballast water (plus whatever’s swimming in it) https://en.wikipedia.org/wiki/Ballast_water_discharge_and_the_environment#/media/File:Ballast_water_en.svg.  Ocean-going ships routinely enter the Great Lakes via the St. Lawrence Seaway, and equally routinely, have emptied their ballast water into the Great Lakes.  In 1993, a difficult-to-enforce law was passed that required incoming ships to replace their home-grown ballast water with ocean water before entering the Seaway,

In 2011, New York State, gatekeeper for the St Lawrence Seaway, proposed stiff, new regulations about ballast water management/treatment.  Three (short-sighted) Midwestern governors pushed back, citing concerns about job loss, even though some innovative alternative transport was suggested at the time. 

Zebra and quagga mussels turned out to be plenty adaptable – although they originated in salt/brackish water, they quickly adjusted to fresh.  They are bottom dwellers that live in clusters in great, huge, astronomical numbers on the floors of lakes (at one site in Arizona, quagga mussels number 35,000 per square meter).

When quagga mussels arrived, they out-competed the zebra mussels.  Although their life histories are similar, the two mussels prefer different habitats.  Zebra mussels like water depths of 6 to 30 feet, and quaggas can live as deep as 400 feet, so zebra mussels grow closer to shore, and quaggas thrive through the deep basins of the Great Lakes.  Quaggas necessarily have a much wider temperature tolerance.  Zebra mussels prefer hard surfaces to grow on, but Quaggas thrive on softer, siltier lake floors.  Both species eat all day, but quaggas continue feeding during the winter, when zebra mussels are dormant (you snooze, you lose).  The BugLady’s photos show them as most people experience them – as “empties,” cast up on the beach. 

Mussels are “filter feeders,” which means that they suck water in through a siphon and run it over their gills.  Food particles, zooplankton, phytoplankton, and nutrients (and pollutants) are strained out of the water by cilia in the gills and are moved to the mussel’s mouth, and the water is expelled through a second siphon.  Wastes are released as mucous-covered, organic packets called pseudofeces (vocabulary word of the day).  An inch-long zebra mussel can filter a liter of water a day.  One liter per day x Biblical numbers of mussels = large bodies of very clean water. 

At first, some people were thrilled – “Yay, the lake is clean again,” shouted the headlines.  Cities around Lake Erie had been battling pollution in the form of algal blooms due to excessive nutrients (fertilizer) in the water.  In short order, you could see the bottom of the lake again (it’s called “nutrient bioextraction,” and it can be a useful tool in controlled situations where the bivalves are removed when they’re finished eating and processed into animal food or, ironically, fertilizer). 

However, the water was crystal clear because there were so few nutrients left in it, and native species that depended on the food in those liters of water were out of luck.  It was an all-out attack on the base of the food web.  Zooplankton feed on phytoplankton and are fed upon by larger animals, including tiny fish, which, in turn, feed bigger fish and a variety of other vertebrates.  But nutrient theft is not the only problem with these mussels. 

  • Quaggas eat algae, but they’re picky, and non-toxic algae are their favorites.  What’s left after they feed is higher concentrations of the more troublesome algae. 
  • Light is able to penetrate deeper into that nice, clean water – UV rays are bad for the very young fish but great for plants, opening the door for more algal blooms.  Decaying algae, some carrying harmful bacteria, wash up on beaches or lurk just offshore.
  • The clear water can allow thick growths of other aquatic plants, too, fertilized by nutrient-rich mussel poop.  Dense aquatic vegetation discourages swimming, fishing, and boating. 
  • Our native shellfish are indicators of the health of their environment.  The invasive mussels turn lake beds hard and lumpy, with wall-to-wall shells, making it hard for native bivalves to find favorable habitat.  To add insult to injury, zebra mussels will piggyback on native mussels, hindering their feeding and ultimately smothering them.  Great picture at: http://www.startribune.com/mussel-bound-lakes-could-imperil-birds/133021828/.  Said one fisheries biologist, “When I’m diving in the Mississippi River, if I come up with a ball of zebra mussels, I know that when I break that open, I’m either going to have a snail or a mussel — a native clam — inside that ball of zebra mussels.”
  • Old zebra and quagga mussel shells wash up on shore, often in sharp fragments, problematic for barefoot beach-goers.  
  • Zebra mussels overgrow anything that stands still long enough, especially pilings and other underwater surfaces, and they clog utility water intake/cooling pipes, requiring costly fixes.  Researchers in a few northern lakes have observed an odd (and one-sided) association – zebra mussels growing on the backs of clubtail dragonfly naiads (immature clubtails may live underwater for several years, giving mussels plenty of time to gain a foothold).  Their exoskeletons are effectively glued shut by mussel filaments on the thorax, where the exoskeleton normally splits to release the adult dragonfly, so naiads crawl up on shore and die there, unable to emerge.
  • As they feed, quagga and zebra mussels accumulate toxins, with some pollutants occurring in their tissues (and their pseudofeces) in concentrations measuring many thousands of times higher than in the surrounding water.  Those toxins (including Clostridium botulinum) get passed up the food chain in a process called biomagnification.
  • A mass of pseudofeces on the lake’s floor requires oxygen in order to decompose. 

Lake Superior has mostly avoided this mess, probably due to a combination of its much colder temperatures, lower levels of nutrients in the water, and its water chemistry – very little calcium for growing strong shells. 

Mussel reproduction is external and chancy.  Males and females release their bodily fluids into the water, nature takes its course (aided by water currents and propinquity), and fertilized eggs hatch into a life stage called veligers.  An adult female can produce as many as a million eggs annually, and her life span is three to five years, but the attrition rate for eggs and veligers is huge (they’re even eaten by filter-feeding adults).  Mom and Dad may be stuck in one spot, but their offspring are, temporarily, free-swimming, and currents can carry them great distances.  Veligers swim and feed for four or five weeks before they must attach, and they mature by their first birthday. 

What slows these critters down?

  • Fish, like yellow perch and redear sunfish, and waterfowl, especially diving ducks like goldeneye and scaup, have learned to love the invasive mussels (98% of a Lesser Scaup’s diet is zebra mussels).  Kudos also go to the equally alien and equally invasive quagga-eating Round goby fish.  Alien species that become invasive do so because they have left their native predators behind.  In this case, the predator caught up with the mussel, but, alas, this aggressive little fish damages native fish populations, too.
  • A patented bacterium called Zequanox targets these two mussel species only and has a 90% mortality rate, but it’s far too expensive to apply to a Great Lake.  There’s a copper-based treatment, too.
  • Unusually warm water – In 2001, the water temperature in parts of the Upper Mississippi reached 89 degrees F, and masses of zebra mussels died. 

Good news-Bad news: For zebra mussels in the Great Lakes, the show is over, but they’ve simply been replaced by quaggas, and scientists doubt that the Great Lakes will ever return to their pre-alien-mussel state.  At this point, Lake Michigan (the 6th-largest freshwater lake in the world) is essentially a man-made ecosystem that’s being managed as a fishery, because the base of the food web is so messed up.   

For those people whose attitude toward alien species is “Get over it – A species is a species!  New species = more biodiversity,” the BugLady has one word. “Seriously???”

For all your invasive species needs, remember our own Southeastern Wisconsin Invasive Species Consortium (SEWISC), https://sewisc.org/, a wealth of information about invasive species already in the state and on the horizon.  

Be assured that the BugLady did not use any of the information presented in the article about “Zebra Muscles” (ain’t Spellcheck grand?). 

The BugLady


2025   So – what’s new?

ZEBRA MUSSELS

  • An ounce of prevention is worth a pound of cure – it can be time-consuming and expensive to try to get rid of them once they’re established (and they’ve usually been around for two or three years by the time anyone notices them).  Most boat launches have signage about hosing off the trailer, boat, live wells, bilges, and motor, but the list should also include swimsuits and wetsuits – the veligers can live for three to five days out of water.
  • Researchers in Minnesota drew a direct line from large Zebra mussel infestations in inland lakes to some staggering increases in mercury levels in game fish in those lakes (up 72% in walleyes and a whopping 157% for yellow perch!).  In the waters well-filtered by invasive mussels, walleye fry fail to thrive.
  • Sheephead, pumpkin seed sunfish, and carp will eat Zebra mussels, but apparently, non-native mussels are less nutritious than the native mussels, and the fish are stunted (the BugLady is blown away that someone figures these things out).

QUAGGA MUSSELS

  • The belief in Lake Superior’s resistance to Quagga and zebra mussels turned out to be wishful thinking, but the populations seem localized – Apostle Islands, Isle Royale, and a few harbors.  Water that averages 40 degrees does seem to discourage them.  
  • The population of Whitefish has plummeted by 80% in some parts of the Great Lakes, due to Quagga mussels.  There are estimates of quadrillions of Quaggas in the lower Great Lakes.

Quaggas may have completed their conquest of Lake Michigan, but their spread into our inland lakes is just starting.  They were recently found in Geneva Lake, a deep lake whose substrate is 95% sand.  In a survey they did at Geneva Lake, the DNR found that a quarter of the boats had been used on a different water body in the past five days.

Kate Redmond, The BugLady

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

Bug o’the Week – Common Aspen Leaf Miner

Bug o’the Week
by Kate Redmond

Common Aspen Leaf Miner

Greetings, BugFans,

Leaf miners have been mentioned in these pages before – even the Aspen leaf miner (Phyllocnistis populiella) has appeared briefly.  When she did a little more research, the BugLady was ecstatic to discover that Aspen leaf miners have an association with EFNs, one of the coolest things she’s ever found out about in her 16 years of writing BOTW (more about that in a sec).  Here’s its story.

First of all, a quick and dirty leaf miner review.  They are (primarily) the tiny larvae of a variety of species of fly, beetle, moth, or sawfly (Hymenoptera), and they are everywhere.  They mostly feed on sap or tissue that they encounter as they chew their way around inside a leaf, between its top and bottom layers, some feed in fruit, and some can process plant tissues that are toxic.  Leaf miners are found on plants in most plant families (as J. R. Lowell once said, “There’s never a leaf nor a blade too mean to be some happy creature’s palace.”), and some are extreme specialists, using only one or just a few plant hosts.  They are often active in mid-to-late summer, and they transform plant energy into animal energy for the birds and insects that know their secret hiding places.  

They create distinctive patterns that, along with the identity of the plant, help us to name them.  Mines are roughly divided into three categories – serpentine, blotch, and tentiform.  Most mines and their miners do not cause significant damage to their host – as J. G. Needham said in “Leaf-mining Insects” (1928), Not only does their minute size partially excuse them, but in feeding habits most are very precise and economical of tissues.  They take just enough to sustain and mature their own lives, and they injure little tissue save that that they ingest.”

Leaf miner is more a culinary and lifestyle grouping than a scientific/taxonomic classification.  For more background on leaf miners, see https://uwm.edu/field-station/bug-of-the-week/leaf-miners/

There are a dozen members of the genus Phyllocnistis (from the Greek meaning “leaf scraper”) in North America.   They’re in the family Gracillariidae, the Leaf Blotch Miner Moths, and they are small and fringed, with wingspreads under ½,” (“micromoths” – another not-quite-scientific designation).  Their larvae, flattened and rudimentary, spend their first three instars chewing serpentine trails in the leaf tissue, guzzling sap, and leaving behind a trail that’s punctuated by a line of frass (bug poop) (an “instar” is the active, feeding stage between molts).  The larva doesn’t feed in its fourth and final instar; it gets itself to the margin of the leaf, where it spins a cocoon and pupates in a spined pupal case (some kinds of leaf miners drop to the ground to pupate, but not this bunch).   

The Aspen leaf miner stars in a number of Extension horticultural bulletins, but its impact, other than cosmetic, tends to be minimal.  If there’s a black sheep in the genus, it’s the Citrus leaf miner https://bugguide.net/node/view/1318589/bgimage.

COMMON ASPEN LEAF MINERS, aka Aspen serpentine leaf miners, are found across southern Canada and the northern half of the US, wherever quaking aspen grows.  Some sources said that poplar and cottonwood are also used as hosts, and some said that the main host is aspen, and some said that mines found on cottonwood and poplar are made by a different species.  The tiny moths have pale, narrow wings and long-ish antennae, and they often perch slanted, with the front half of their body “on tiptoe” https://bugguide.net/node/view/1582507/bgimage.  

For a small, relatively harmless insect, there’s a surprising amount of biographical information available.  They overwinter as adults, avoiding freezing through careful selection of a winter shelter and because of their ability to supercool themselves, dropping their freezing point.  Counterintuitively, they prefer to overwinter under spruce trees rather than aspens, because the deeper snow cover below the aspens translates to wetter conditions as the air warms, and ice in a late freeze.

Romance blossoms in spring, and females lay their eggs on the edges of emerging leaves, near the tip, usually only one egg per leaf, and then they fold the edge of the leaf over to protect the egg until it hatches.  When it does, the larva https://bugguide.net/node/view/204391/bgimage, chews through the floor of the egg, directly into the leaf, where it will live until it emerges from its pupa as an adult in fall.  

Larvae eat the sap that they generate while tunneling.  A research team tracked the mining habit and found that:

  1. A single caterpillar may mine an entire small leaf https://bugguide.net/node/view/30617/bgimage, but only part of a large leaf until it has consumed enough calories to pupate;
  2. When the larva gets to the midrib, it turns toward the leaf’s base, and when it gets there, it turns again and follows the leaf margin for a while before heading for the midrib again;  
  3. Sometimes more than one egg is laid on a leaf.  A larva may not know that it has company in the leaf, but if two larvae discover each other, they generally feed and pupate on opposite sides of the midrib;
  4. They don’t re-mine an already-mined trail;
  5. Larvae pupate at the edge of the leaf.

Heavy feeding on the epidermis of a small leaf can interrupt its photosynthesis, causing leaves to dry, turn brown, and fall prematurely, but aspens have lots of leaves, and the Common aspen leaf miner larvae, as Needham said, don’t eat much. 

Adults https://bugguide.net/node/view/1128097/bgimage feed on nectar that they find in extrafloral nectaries (EFNs) at the base of the leaves (between one-third and three-fourths of aspen leaves have them).  Here’s a BOTW about EFNs – https://uwm.edu/field-station/bug-of-the-week/ants-in-my-plants-rerun/

And here’s “Leaf-mining Insects” by J. G. Needham, et al, https://www.biodiversitylibrary.org/item/28922#page/7/mode/1up

The BugLady saw a Common Green Darner last week – let the Wild Rumpus begin!!

It’s Earth Day/Week – remember, there’s no Planet B.

Kate Redmond, The BugLady

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

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