Category: Bug of the Week

Bug o’the Week – A Tale of Two Robber Flies

Bug o’the Week
by Kate Redmond

A Tale of Two Robber Flies

Greetings, BugFans,

The BugLady was walking at Riveredge Nature Center one day in mid-June when she spied a small Robber fly perched on a leaf, hanging onto its prey.  When she put the picture up on the monitor, she recognized the predator as a small (barely ½”) Robber fly named the Stripe-legged robber fly (family Asilidae).  Then she tried to figure out what it was holding.  It kind of looked like a midge, and that’s how she (uneasily) ended up labeling the picture.  Then, as she often does, she entered her dragonfly list for the day at the Wisconsin Odonata Survey (https://wiatri.net/inventory/odonata/) website and sent her butterfly list to the Wisconsin Butterflies page (https://wisconsinbutterflies.org/).  Mike Reese, who runs the site, is also interested in Tiger beetles and Robber flies, and he knew what the prey was.  Many thanks, Mike.

First, the predator, the STRIPE-LEGGED ROBBER FLY

North America is home to a wide variety of alien/exotic/non-native plant and animal species.  Along with famous invasives like Purple loosestrife, Garlic mustard, Emerald ash borers, and Spongy (Gypsy) moths (see https://sewisc.org/), we also have non-native species that keep their heads down and are not invasive – butterflies, daddy longlegs, orchids, and more.  The Stripe-legged, aka the Glassy-winged, aka the European Longhorn robber fly (Dioctria hyalipennis) is one of two non-native Robber flies.  The species name “hyalipennis” comes from the Greek word hyalo (“glass” or “clear”) and the Latin word pennis (“wing” or “feather”). 

Their original haunts were sun-dappled shrubby/woody areas, parks, yards, hedgerows, and field edges in western Europe and northern Africa, but they found their way across the Pond and were first spotted around Boston in 1916.  Today they are found throughout the northeastern quadrant of North America (plus, inexplicably, in Seattle and Denver).  They’re not uncommon in the areas where they occur, and they’re said to be somewhat gregarious.

Like other Robber flies, they spot their prey from a perch and fly out to grab it.  And, like other Robber flies, they may go after prey that’s almost as big as they are.

One source pointed out that as Robber flies go, Stripe-legged robber flies are not particularly spiney, but since many of the small insects they eat are soft-bodied, like flies, small moths, and leafhoppers, robust spines on the legs aren’t as critical.  They also tackle pygmy grasshoppers, bees, and wasps.  Matt Pelikan, who writes an excellent Nature column for the Martha’s Vineyard Times, describes it: “Perched glassy-winged robbers are constantly alert, and visibly track any object that flies near them, adjusting their stilt-like legs and pivoting their heads to keep the target in view. Fast-moving insects are left alone, but when a suitable target putters past, Dioctria launches and zeroes in on its victim. As with most robbers, a high percentage of attacks connect.” 

He continues, “The process is too fast to watch. The robber grasps its victim and rams pointed mouthparts into its body, injecting a blast of enzymes that both paralyze the prey and begin to break down its tissues. Robbers, with spindly necks, surely don’t have neck muscles that allow them to “peck” their way through a victim’s exoskeleton; I surmise that they grasp the victim with their legs and pull it against their beaks, with the hairs and spines on a robber’s legs being there to assure a firm enough grasp to do this.

…  It doesn’t take Dioctria long to drain a typical victim: after five minutes or so, the emptied husk is tossed overboard, and the robber fly resumes scanning for its next meal.

A Piper Cub in a family of fighter planes, the glassy-winged robber fly may be the shortest, lightest, least well-defended, and slowest-flying member of this group. You might think those traits would be disadvantages in a predator. But a lot of dead leafhoppers argue otherwise. Dioctria is perfectly adapted to find and catch a class of prey that is both abundant and vulnerable.” 

And the Prey? A PAINTED PIXIE

When Mike looked at the picture, he identified the prey as another Robber fly – at ¼”-ish, the smallest one we have, a Painted Pixie (Beameromyia pictipes) (pictipes comes from “picti” – painted- and “pes” – foot).  He went on to say that he has seen them around southern Wisconsin, and the BugLady takes off her hat to him – if anyone can spot a midge-sized Robber fly, it’s Mike. 

Sources generally conclude that there’s little information about the Painted Pixie because it’s rarely observed.  So, the BugLady backed up a couple of notches taxonomically to its subfamily, Leptogastrinae.  Species in the subfamily tend to be small and inconspicuous.  Some species tweak the general Robber fly MO and hover before picking up prey that’s sitting on vegetation.  Or spiders from their webs – the Leptogastrinae eat more spiders than other groups of Robber flies do.  Here are some spectacular (sub)family pictures https://robberfly.org/leptogastrinae/

The genus Beameromyia is a very small genus with 15 species in North America and only 24 worldwide.  Most of our species are found in the Southwest.  These are tiny, slender, long-legged flies that have variously swollen hind legs.  They’re found in the east and Midwest in the semi-open areas, where they feed on very small spiders and flying insects.

[Caveat emptor – one site that presented pictures and “facts” about the genus Beameromyia was, in fact, just plugging in generic Robber fly information, and stated that “As members of the Asilidae, these predatory flies are characterized by their robust build and predatory habits.”] 

In a monograph on the revision of the classification of the subfamily published by the American Museum of Natural History in 1957, Charles H. Martin wrote that the range of

Beameromyia pictipes “seems to be a narrow belt extending from Kansas to Maryland.”  Robber Flies of the Southeast lists their range as the Eastern and Midwestern US, where along with dappled woods and edges, their habitat includes old fields and grassy dunes

And the BugLady’s photograph of the two?  Right time, right place, right toys. 

Finally, a correction:  alert BugFan Tod noted that in last week’s salute to spring, the BugLady misspelled the name of the Duskywing, writing “Juvenile’s” Duskywing instead of Juvenal’s.  Juvenal was a Roman author of satirical poetry, and the BugLady has no idea how that connects with butterflies.  Thanks Tod.

Kate Redmond, The BugLady

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

Bug o’the Week – Spring Summary

Bug o’the Week
by Kate Redmond

Spring Summary

Howdy, BugFans,

Now that summer has arrived with a vengeance, it’s time to take a quick look back at some spring bug experiences.

BUMBLE BEE ON PINK LADY’S SLIPPER – A website about Wisconsin’s native orchids lists “naïve bumble bees” as pollinators.  Naive bumble bees.  Lady’s slipper orchids do not offer a nectar reward to foraging insects, but it takes a few visits to the orchids before a bee figures that out and looks elsewhere.

FIRE-COLORED BEETLE, in the family Pyrochroidae (which means “fire color”) seems like an odd name for a mostly-black beetle, but some members of the family are https://www.bugguide.net/node/view/1235995/bgpage, and many of the others have that nice, red thorax.  The BugLady saw it from afar, sitting on the tip of a skunk cabbage leaf – she’s been accused of using her zoom lens as binoculars, and she pleads guilty.  This contributor to bugguide.net got a far better picture https://www.bugguide.net/node/view/1796471. 

She thinks this is Schizotus cervicalis, who goes by the awesome name of Flaming pillow beetle (because of the males’ puffy, red thorax).  Fire-colored beetles have an interesting relationship with Blister beetles, which is explained in a BOTW about a related Fire-colored beetle in 2012 https://uwm.edu/field-station/bug-of-the-week/fire-colored-beetle/. 

DARK FISHING SPIDERS are big (leg-spread up to 3”), long-legged spiders that really get people’s attention. This one, found in late May, was about half-grown and was in the process of regenerating a leg.  Its ability to regrow legs depends on age and molting.  The small, new leg emerges after a molt and grows after each subsequent molt, but most spiders don’t molt after they become adults, so the new leg might not fully develop.  Spiders can generally get along just fine despite a missing leg. 

JUVENILE’S DUSKYWING – Duskywings are skippers (family Hesperiidae) and skippers are butterflies (though some sources still call them “butterfly-like”), although at one time they were considered a transition group between butterflies and moths.  Skippers tend to have large, chunky, hairy bodies in proportion to their short wings, and they have a tiny, “crochet hook” at the tip of their antennae.  They get their name from their quick, bouncy flight.  The Juvenile’s Duskywing is an early season butterfly that likes to perch on the ground. 

NORTHERN PAPER WASPS are the wasps that tuck disk-shaped, open-faced nests up under the eaves https://www.bugguide.net/node/view/2109317/bgimage.  Most are yellow and black (Nature’s warning colors) but some are reddish https://www.bugguide.net/node/view/2316444/bgimage. 

STAG BEETLES (Lucanus placidus) emerge from their underground pupal cases in late spring.  Adults live only a few weeks and are said to feed on flower nectar (the BugLady would like to see that) and on tree sap, and the larvae feed on decaying trees and roots (they don’t kill the trees, but they help to dispose of them).  Read about one man’s encounter with these lunker (1 ½”) beetles https://insectlab.russell.wisc.edu/2016/06/23/buckets-of-beetles/.

ACANTHOCEPHALA TERMINALIS (no common name) is a leaf-footed bug that can be seen over several generations from late spring through early fall, though the BugLady has never seen one this large in mid-May.  The flanges on its hind legs explain the “leaf-footed” part of its name, and its species name – terminalis – refers to the golden tips of its antennae.  It is in the True Bug order Hemiptera, and though it’s not officially a Stink bug, it can deploy a smelly chemical when threatened (though it would rather fly than fight).  This is the only genus member here in God’s Country.

Their nymphs are pretty cute, too https://www.bugguide.net/node/view/1644287/bgimage.

CRAB SPIDER ON VIOLET – The BugLady was surprised to see an adult Goldenrod crab spider decorating a violet in the first week of May.

Were there butterflies?  Yes.

MOURNING CLOAKS are, for butterflies, very long-lived – when you see one in May, it’s about 10 months old and at the end of its trail.  One of the few butterfly species that overwinter as adults, Mourning Cloaks are often seen during January thaws and maple sap season (they tuck themselves back into a sheltered spot when the cold returns), and they’re an early butterfly in the woods in spring.  How do they do it?  They’ve got a lot of insulating hairs; they use isometric exercises to warm the flight muscles in their thorax, and they count on tree sap and rotting fruit for food, rather than flowers.  It will mate, lay eggs, and die, and its caterpillars will eat, metamorphose, and fly for a while, but then it will aestivate (become dormant) to avoid the wear and tear of summer before returning to the air to finish out the year.

HOBOMOK SKIPPERS are the first of the skippers to hit the airways, appearing in sunny clearings and edges as the wild geranium starts to bloom.  They’re on the wing before the BugLady develops her annual case of “Skipper Brain” – for a brief time, she is (almost) positive of her skipper IDs.  Hobomok Skippers are part of a series of butterflies named by Thaddeus W. Harris and others after Native American chiefs. Hobomok was the “chief of the Wampanoag Indians, who helped the Pilgrims upon their landing in Plymouth in 1621.”

And were there dragons and damsels?  Oh, you bet, though the dragonfly season has gotten off to a very slow start!  The majority of invertebrates that the BugLady’s camera finds are dragons and damsels. 

EBONY JEWELWING – What would a spring report be without a spectacular male Ebony Jewelwing?  Along with very showy rubyspots https://www.bugguide.net/node/view/2178678/bgimage, jewelwings are in the Broad-winged damselfly family Calopterygidae (“beautiful wing”), the river damsels.  Don’t look for them around quiet ponds.  They put their beauty to good use in their showy courtship displays. 

DOT-TAILED WHITEFACE – No doubt that this is a whiteface – here’s the dot-tail https://www.bugguide.net/node/view/26379.

We were so busy celebrating National Moth Week last week that we neglected to celebrate the simultaneous National Pollinator Week!

Kate Redmond, The BugLady

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

Bug o’the Week – A Quartet of Moths

Bug o’the Week
by Kate Redmond

A Quartet of Moths

Greetings, BugFans,

In honor of National Moth Week, here are three lovely moths that the BugLady has found recently, plus one from BugFan Freda (the BugLady’s definition of a “lovely moth” includes being identifiable).

In the past, moth books, including Holland’s venerable, century-old Moth Book, upon which the BugLady cut her teeth, entomologically speaking, pictured moths in a pinned position, with the front wings stretched forward so that their trailing edge stands at right angles to the body, and the hind wing extends behind it.  Yes, this dorsal view makes visible the patterns on the upper surfaces of all four wings, but most moths just don’t sit like that out in the field, and posture can be a great clue in identifying them.  Newer guides, like the Peterson Field Guide to Moths of Northeastern North America and Sogaard’s Moths and Caterpillars of the North Woods show the moths at rest – wings extended in a V, wings folded, wings stacked over their bodies, or wings wrapped around it.   

Remember, the Order Lepidoptera includes both the butterflies and the moths, and although they are less charismatic, moths overwhelmingly outnumber butterflies by 180,000 species to 20,000 globally and by 11,000 species to 700 in North America.  Although numerous, moths are shy and retiring and most do no harm, so biographical information for many is scanty.

The DARK-SPOTTED PALTHIS, AKA the Angulated snout-moth (Palthis angulalis) is a poster child for how different a pinned specimen https://www.bugguide.net/node/view/1263477/bgimage can look compared to a live moth.  Even its dorsal view https://www.bugguide.net/node/view/2178817/bgimage doesn’t really match the gnarled and twisted side view.  Thanks to BugFan Freda for sharing.

Dark-spotted Palthis moths are in the family Erebidae and in the subfamily Herminiinae (which used to be a separate family), the Litter moths, so called because the caterpillars of many species feed on dead leaves.  They have a wingspan of about an inch, and there can be a lot of variation in color https://www.carolinanature.com/moths/palthisangulalis.html.  Males have long, sensory organs (palps) attached to their mouths that are sometimes called “a snout” https://www.bugguide.net/node/view/1291220/bgimage, and several authors said that they resemble jet planes because of the way the curled/folded outside edges of their swept-back wings.    

They’re found in woodlands across the eastern half of the continent, with some records in British Columbia.  Caterpillars https://www.bugguide.net/node/view/2485329 eat living or dead leaves, flowers, and fruits of a wide variety of woody plants like basswood, birch, alder, maple, willow, some conifers, and more, and some herbaceous plants like aster and goldenrod.  

The STRAW BESMA (Besma endropiaria) is in the family Geometridae, whose caterpillars are called the Earth-measurers or inch worms.  Straw Besmas are found in woodlands east of the Great Plains. 

Sogaard describes the caterpillars https://www.bugguide.net/node/view/1142291/bgimage as “looking like a reddish twig” and goes on to say that they are “prime examples of what was dubbed ‘vegetable disguise’ by Alfred Russell Wallace” (the naturalist/polymath who lived from 1823 to 1913, whose independently published theory of evolution through natural selection is said to have spurred Charles Darwin to collect his thoughts and publish on the matter).  They feed on a variety of hardwoods like alder, birch, oak, and especially sugar maple, and they overwinter as pupae.

The YELLOW-DUSTED CREAM MOTH (Cabera erythemaria), another Geometrid, is found in sunny woodlands and edges and thickety stream sides.  At first glance, it’s another little, white moth, but a second glance reveals fringed wings peppered with tiny, black dots and divided by subtle, yellow lines.  The BugLady couldn’t find any explanation of the species name erythemaria, which suggests that something is red, unless it refers to markings on the caterpillar.

Caterpillars https://wildcolumbia.org/wp-content/uploads/2023/03/original.jpg love willow leaves, but they also feed on birch and blueberry.  They overwinter as caterpillars.

(When the BugLady was researching the Yellow-dusted Cream moth, the always-excitable internet posed a few related questions, like “Are Yellow moths dangerous?” and “Are yellow moths poisonous?”  No and No.)

The DECORATED OWLET (Pangrapta decoralis, family Erebidae) looks (and sits) like a small butterfly and is another species whose unique posture would be lost in a pinned specimen.  The BugLady posted it on her Facebook page as an as-yet-unidentified moth and got an ID within hours (thanks, Robert).  It comes in a variety of colors and patterns https://www.bugguide.net/node/view/2265925/bgimage, https://www.bugguide.net/node/view/2412939/bgimage, https://www.bugguide.net/node/view/2017389/bgimage, https://www.bugguide.net/node/view/682515/bgimage, and researchers suspect that it is part of a complex of three sibling species – species that look the same but are “reproductively isolated” – they do not interbreed.  In other words, we may not be able to tell them apart, but they can.  They are close relatives that have recently diverged. 

They are found over much of Eastern North America, and their caterpillars https://www.bugguide.net/node/view/936111/bgimage eat blueberry and huckleberry (this one was found in a bog, surrounded by blueberry and huckleberry).  They overwinter as pupae.

Go outside – say hello to a moth.

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 – Daisy Fleabane

Bug o’the Week
by Kate Redmond

Wildflower Watch Daisy Fleabane

Howdy, BugFans,

Daisy fleabane (Erigeron sp.) is blooming.  If you’re not familiar with it, the name “teeny daisy” – given to it by the BugLady’s then four-year-old, firstborn child – describes it well.

It’s in the Aster/Composite family Asteraceae, so each fleabane “flower” is actually a whole bouquet made up of a mass of tiny, central flowers called disc flowers and an outer rim of ray flowers.  But the Asteraceae like to mix things up – some family members, like dandelions, consist of only ray flowers, while others, like Beggars’ ticks, have very conspicuous disc flowers and inconspicuous ray flowers, and still others, like Blazing stars (Liatris) and thistles, have only disc flowers.

The word “bane” in a plant’s name usually predicts trouble – for someone, anyway.  In this case, flies, gnats, fleas and other bothersome insects were (allegedly) repelled by the smoke when the plant was burned, and the flowers were dried and added to mattress stuffing and tied into brooms. 

Astringent, anti-inflammatory fleabane plants, flowers, and oils were widely used medicinally by both the Native peoples and the European settlers to treat migraines, gout, sore muscles, epilepsy, skin issues, “female problems,” fevers, heart troubles, and more, and the dried flowers were used as a snuff to break up nasal congestion.  The Lakota name for fleabane translates to “sore mouth medicine.”  It was also one of the plants that were smoked in pipes.

Bugs like it, too.  As always, the BugLady found insects and spiders who came to rest, to eat, and to be eaten, and with all that going on, some pollination happens, too.  Today’s episode is a bit moth-heavy because we are approaching National Moth Week. 

BI-COLORED PYRAUSTA MOTH – The BugLady has been seeing these small moths (wingspread just over ½”), but they don’t stick around to have their portraits made – they make a rapid, scrambling flight and then tuck themselves in under a leaf.

A CRAB SPIDER waiting for a little carry-out.

WAVY-LINED EMERALD – If you’re going to feed in plain sight in the daytime, you need a disguise.  This caterpillar makes its own by clipping bits of fresh petals and sticking the pieces to spines on its back https://www.bugguide.net/node/view/1038322/bgimage.  When the vegetation dries, the trim makes it hard for birds to spot them.  Here’s what it will look like when it grows up https://www.bugguide.net/node/view/2260155/bgimage.

A ROBBER FLY enjoying a meal.

IRIS WEEVIL – The BugLady has seen more Iris weevils on fleabane and ox-eye daisies than she has on irises.  Adults chew into the iris flower’s ovary and oviposit there.  While the adults are feeding on the flowers, pods, and seeds, the larvae within eat seeds and their surrounding tissues.  This doesn’t affect the health of the plant, but the weevils are not welcomed by people who want to harvest iris seeds.

KATYDID – Katydid nymphs are awesome.

RIPIPHORUS BEETLE – One of the “wedge-shaped” beetles in the family Ripiphoridae (which comes from a Greek word meaning fan carrier, a reference to the fancy antennae sported by the male).  Ripiphorus fasciatus is a beetle dressed like a fly, a disguise that undoubtedly allows them to cozy up to other insects on flower tops.  Females oviposit there, and their unusually-energetic larvae stand erect on the flowers, ready to board ground-nesting, solitary bees so that they can be transported back to the bee’s egg chambers.  There, they enter an egg chamber and then enter the larva in the chamber and consume it from the inside.  Look fast – males live for a single day, and females for not much longer.

SYRPHID FLY – Some syrphid/flower/hover flies are chunky bumble bee mimics, but some are delicate and beautifully-patterned, and when they land on your skin (to check out its salt content) your skin feels minutely cool.

ARCTIC SKIPPER BUTTERFLY – Officially the BugLady’s favorite skipper because although it is, like many skippers, brown and orange, you can’t mistake it for any other species.  They have a preference for bluish/purplish flowers, but fleabane works, too.

SPOTTED THYRIS MOTH – This chunky, little moth has a wingspan of just under a half-inch, so it fits easily on the fleabane’s disc flower.  Although they’re a day-flying moth, they’re easily overlooked, because they’re slightly smaller than a honeybee, and so they’re probably more common than we realize.  The Prairie Haven blogger (https://www.prairiehaven.com/?page_id=8920) says that “They looked like tiny crumpled butterflies.”

TACHINID FLY – Lots of tachinids are bulky, bristly, and house-fly-shaped.  Not Cylindromyia.  Tachinid flies are parasitic flies, many of which are considered beneficial biological controls of agricultural pests.  Not Cylindromyia.  This wasp-mimic targets a few species of predatory stink bugs that are, themselves, biological controls, plus some of the giant silk moths (Cecropia, Polyphemus, etc.).  

BLACK AND YELLOW FLOWER BUPRESTID – A.K.A. the Yellow-marked Buprestid, Hairy Yellow-marked Buprestid, Spotted Flower Buprestid, Beautiful Flower Buprestid, and Flat-headed Sapwood Borer.  Buprestids, many of which are tough-looking, bullet-shaped beetles, are known as the Metallic Wood-borers (though this one is dull and hairy rather than shiny).  Adults eat pollen and nectar and are hard to spot on yellow flowers; larvae are wood borers. 

All of the stars of today’s episode have also starred in their own BOTWs, which you can find by typing into the search box “UWM Field Station Arctic Skipper,” or “Iris weevil,” or whatever. (it took the BugLady an embarrassingly long time to figure that out).

Go outside – check the fleabane.

Kate Redmond, The BugLady

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

Bug o’the Week – And Now for Something a Little Different XIX – American White Pelican

Bug o’the Week
by Kate Redmond

And Now for Something a Little Different XIX American White Pelican

Howdy, BugFans,

2026: The BugLady spent the morning watching pelicans; photographing pelicans on the water, on the beach, and, in small squadrons, in the air; and editing pictures of pelicans.  They’re having a moment in her neighborhood at the edge of Lake Michigan.  There are two floating about far offshore right now – brilliant in the sunlight.

Here’s an article she wrote about them two years ago for the newsletter of the Lake Michigan Bird Observatory.

2024: Just before 3:00 PM on October 6, the last new species of the Big Sit! was spotted from the tower – two White Pelicans that were working their way north along the shoreline. A single bird flew south over the tower the next day. 

Wait! – pelicans live where the land touches the oceans, right? Well, yes. And – no. Brown Pelicans are certainly creatures of salt water, and when one shows up in Wisconsin, it’s a big deal, but American White Pelicans are native not only to the coasts but also to the Upper Midwest and to the prairie potholes of the northern Great Plains.

They’ve been present in Wisconsin for a long time, though it’s not known whether the birds reported by Indigenous tribes and early European settlers were breeding or migrating. They made a big target for the early settlers, despite the fact that, as one said “they have an oily flavor, whether alive or dead, which is so disagreeable that it is impossible to eat them.”  Wisconsin’s first modern breeding records occurred in 1995 (Green Bay) and 1997 (Horicon Marsh), and the newcomers probably hailed from North Dakota. For an interesting history of White Pelicans in Wisconsin, see https://swibirds.org/fff/2020/6/19/american-white-pelican.  Here’s a map of their present range https://www.allaboutbirds.org/guide/American_White_Pelican/maps-range.

The American White Pelican’s scientific name, Pelecanus erythrorhynchos, means “red-billed pelican.  The German naturalist who named it based his description on the writings of an English ornithologist who called it the Rough-billed Pelican. John James Audubon, waxing poetic, added “American” to its name, saying, “In consequence of this discovery, I have honored it with the name of my beloved country, over the mighty streams of which may this splendid bird wander free and unmolested to the most distant times, as it has already done in the misty ages of unknown antiquity.“

White Pelicans typically feed on minnows, shiners, carp, and suckers, but they’ll eat game fish, tadpoles, crayfish, and salamanders, and sometimes they adopt commercial catfish ponds. Unlike Brown Pelicans, they don’t plummet into the water from the sky; they hunt while swimming on the surface.  White Pelicans often forage alone, but a group may cooperate to encircle a school of small fish, drive it toward shore, and then share the results.  They sometimes steal food from other birds, even from the beaks of other pelicans that are feeding their young. During the breeding season, they often feed at night, locating fish by touch. 

A bird this size has few predators, but foxes and coyotes do damage in breeding colonies, and ravens, gulls, Great Horned Owls, Red-tailed Hawks, and eagles prey on eggs and nestlings.

After a courtship that includes strutting, bowing, head swaying, circling in the air, and jabbing at potential nest spots, pelican pairs settle down in communal nest areas, often on islands for protection. They lay two or three eggs but usually fledge only one young. Competition is stiff – it takes about 150 pounds of food to launch a young bird – and the first chick to hatch may eventually eliminate its nest mates (siblicide). Chicks can crawl by two weeks, walk by the end of three weeks, and fly by 10 weeks. When they’re about three weeks of age, chicks leave their nests and gather with other chicks in a group called a “crèche,” but they return to the area of their old nest to be fed.

FUN FACTS ABOUT WHITE PELICANS

  • The North American bird with the largest wingspread is the California Condor (9.5+ feet). With a nine-foot wingspan, the White Pelican is the second largest, and at almost 30 pounds, is one of the heaviest flying birds.
  • White Pelicans are hardy enough to overwinter in Wisconsin if they can find open water. They can be seen on this bird cam on the Mississippi near LaCrosse very early in spring and into late fall  https://explore.org/livecams/raptor-resource-project/mississippi-river-flyway-cam.
  • Adult White Pelicans have a vocabulary of grunts, but nestlings are more vocal, making loud begging calls. Even pelican embryos get into the act, squawking from inside the egg when they are too hot or too cold. To hear Pelican sounds https://www.allaboutbirds.org/guide/American_White_Pelican/sounds.
  • White Pelicans don’t have a brood patch – an area of bare skin where body heat is transmitted to their eggs. Instead, the parents incubate eggs by placing the webs of their feet over them.

DID YOU KNOW – that a pelican’s beak can, indeed, hold more than its belly can? A lunge fills the pelican’s stretchy pouch with a few gallons of water, and hopefully some fish, too. It tilts its head to let the water drain out of the bill, and the fish are swallowed right away. Pelicans need three or four pounds of fish each day.

On another note, June is Wisconsin’s Invasive Species Action Month. For more information see the Southeastern Wisconsin Invasive Species Consortium (SEWISC) https://sewisc.org/, and https://dnr.wisconsin.gov/topic/Invasives?utm_source=newsletter_101&utm_medium=email&utm_campaign=sewisc-quarterly-newsletter-summer-2026.

Go outside – whack an invasive.

Kate Redmond, The BugLady

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

Bug o’the Week – Wetland Homage – Waterlily leaf beetle

Bug o’the Week
by Kate Redmond

Wetland Homage Waterlily leaf beetle

Greetings, BugFans,

2026: The final installment in National Wetlands Month, though the BugLady would argue that wetlands should be celebrated every month.  The BugLady attempts to photograph this burnished beetle everywhere she sees them – some in aquatic settings as they peruse the flowers of yellow water-lilies, and others on marsh marigolds and skunk cabbage in the adjacent swamps.  They are not huge – most would have to stretch to reach a half-inch – and they often appear to be gold.

2013: The BugLady can hardly pass by a water lily without taking a picture of it, and she confesses that she sometimes “sanitizes” the leaves somewhat during the editing process, Photo-Shopping out some of the mess of frass (Bug poop) and aphid exuviae (shed skins) and holes and discolorations that characterize the leaves of water lilies (especially white water lilies) in mid-summer.  She was reminded recently by BugFan Caitlin that water lily plants are the Center of the Universe for an amazing community of critters that live both above and below the leaf surface.  Someday she will track the colonization of the leaves from the beginning of the season and write a BOTW about it.

Although they are sometimes (confusingly) called Long-horned leaf beetles, Waterlily leaf beetles are in the huge Leaf beetle family Chrysomelidae, and not the long-horned beetle family (equally confusingly, there’s another leaf beetle with the same name).  The subfamily Donaciinae (the aquatic leaf beetles) contains five genera and about 55 species (mostly in the genus Donacia, which today’s beetle probably is, too.  You’d need a microscope and a higher pay grade than the BugLady’s to determine the species).  Donacia comes from Donax, which is Greek for “reed,” and they’re called “reed beetles” in Great Britain. 

WLBs can be found in “weedy” ponds and lakes and very slow streams all over North America.  The adults are leggy, up to a half-inch long, often metallic, with antennae about half as long as their body; they are jumpy and can move fast, and they’re a little camera shy.  The layer of silky hairs that covers their undersides repels water in their often-soggy habitats (settle down, there).  Find them on the surface of a variety of emergent and floating-leaved plants.  Some are generalist feeders and others are plant specialists; some are generalists while the leaves of their favorite plant are still submerged, but they make a bee-line for it when it emerges.  Adults enjoy the leaves of water lilies, arrowhead, potamogeton, and water milfoil, some sedges, rushes and reeds, and they may, like this beetle, eat pollen.

When it’s egg-laying time https://www.bugguide.net/node/view/2309633/bgimage, females of many species of WLB chew a hole in a lily leaf, insert the end of their abdomen, and glue their eggs to the underside of the leaf in concentric arcs – like a mini-rainbow.  Some other species accomplish the same thing while perched on the edge of the lily leaf, and a few crawl up the plant stem, while still others climb under the leaf and down the plant stem. 

According to a report by Paul S. Welch in the Annals of the American Entomological Society, Vol. 9 (1916), the “aquatic” moth (its caterpillar is aquatic) Nymphula maculalis (the Polymorphic Pondweed moth) (really!) takes advantage of the holes excavated in yellow water lily by the female Donacia.  The moth also arranges her eggs on the leaf’s undersurface in up to six concentric arcs, using the spots around the rim of the hole that are not occupied by beetle eggs.  In his study, the author didn’t find a single mass (clutch?) of moth eggs that was not associated with a Donacia egg hole.

The BugLady has never seen a WLB larva (your typical small, whitish, C-shaped beetle grub), probably because most spend their larval lives plugged into a submerged plant stem, never “coming up for air.”  How do they do that?  The eggs hatch in about 10 days, and the larvae drop down through the water column, typically finding the roots and rhizomes (underground stems) of their host plants in the muck (some also feed on stems and petioles).  In the words of Ann Haven Morgan in her Field Book of Ponds and Streams, “When the stems of aquatic plants are broken beneath the water, a flood of air bubbles comes pouring to the surface from the air spaces within them” [that’s why, BugFans, the leaves of floating-leaved vegetation float instead of getting dragged under water – the stems are buoyed up by pockets of air].  “……MacGillivray and others found stems with dozens of little Donacia larvae hanging to them feeding upon the plant tissues, and all breathing air, though they were three or four feet below the surface of the water.”

Pennak, in the venerable Freshwater Invertebrates of the United States, enlarges on the concept.  Insects typically breathe through paired pores called spiracles that are located on the sides of the abdomen.  In the WLB larva, the only spiracles that are operational are the two at the end of the abdomen, and each of these two pores is associated with a sturdy spine.  The larva uses the spines to excavate holes in plant stems, which taps into their inner air pockets, and the air flows out over the spiracles.  Pennak notes that both ends of a larva will be embedded in plant tissue simultaneously. 

Fast-forward to the day, a few weeks later, when a mature grub is ready to pupate.  Using silk produced by glands in its mouth, the larva creates a waterproof cocoon near where it has been feeding.  How do you build a dry haven when you’re underwater?  You tap into the same air, present in the plant tissues, that has been sustaining you as you feed.  You snug your cocoon up against a stem and cut holes through it and into the plant and you allow air to leak in.  As the final touches are being put on the cocoon, the water has been driven out.  O little engineers! 

Although it develops into an adult fairly quickly, the WLB aestivates inside its cocoon until it emerges at the beginning of the next summer.  In a study of a European Donacia, researcher Christian Otto suggested that this arrangement may help the beetle avoid periods of low dissolved oxygen concentrations or may help the beetle time its appearance with the start of the growing season.  When it’s time to exit, the beetle breaks through the cocoon’s tip, carrying enough air under its elytra (wing covers) and belly hairs to sustain it on its trip to the surface. 

Go outside – find a wetland.  Look at stuff!

Kate Redmond, The BugLady

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

Bug o’the Week – 6-spotted Fishing Spider

Bug o’the Week
by Kate Redmond

6-spotted Fishing Spider

Howdy, BugFans,

2026: Week two of our homage to wetlands.  Why wetlands?  Let me count the whys.  For starters, wetlands are fascinating communities that are full of animals that have devised unique ways to deal with the challenges of life underwater.  Wetlands both filter and sponge – removing chemicals from water systems and soaking up extra water to minimize flooding.  More “whys” next week.

2012: This lovely spider is called the SIX-SPOTTED FISHING SPIDER (Dolomedes triton), and yes, the BugLady is aware that there are more than six spots on the animal’s abdomen, but the number refers to dark spots hidden on its underside.  The BugLady wrote a too-short episode about this critter 4 ½ years ago, but she has re-researched the SSFS and so is re-issuing it.

Fishing Spiders are in the genus Dolomedes, in the Nursery web spider family, Pisauridae.  One source said that Dolomedes comes from a Greek word meaning wily or contriving.  Triton was the son of Poseidon.  There are 100-plus members of the genus worldwide, and because of their habitat choices, they’re also called wharf spiders, dock spiders, and raft spiders.  North America has nine of those species – four live in still water; four in streams, and one is found in trees. They are often mistaken for wolf spiders, to whom they are not-so-distantly related. 

SSFSs are found in wetlands, especially wetlands bordered by lots of vegetation, and they’ve developed multiple ways to get around within their habitats.  Although they do not spin webs to snare prey – non-web-spinners are often called “wandering” spiders – SSFSs do make silk for several other purposes. 

They are “opportunistic” carnivores that will eat just about anything that comes along. 

Hungry for fish?  An SSFS can dive underwater (as deep as seven inches) and can easily take a tiny fish; in fact, its strong legs allow it to capture prey that is larger than the spider itself (including small goldfish).  It’s able to walk on submerged vegetation, and it may retreat underwater when alarmed. 

A fishing spider has “book lungs,” alternating layers of air pockets and a blood-like substance.  Its body is covered with short, water-repellant hairs that hold an additional layer of silvery air against its body when the spider submerges.  With this “air tank,” it can stay submerged for more than thirty minutes, but all that air may make it so buoyant that it has to grab a plant or rock to keep from floating to the surface.

It frequently hunts at the water’s surface, where its eight eyes allow it to locate nearby prey visually and where it may stay motionless for several hours waiting for food to appear.  Like a water strider, an SSFS uses the sense of touch in its front legs to detect the struggles of insects that have swooped too low and become trapped in the water’s sticky surface film, or that have emerged from their underwater larval stage and have floated to the surface.  It walks out to its prey, grabs it with hooked front feet, subdues it with venom, and eats it.  It eats the competition, too – other surface-feeders, especially water striders.  Some sources claim that an SSFS can distinguish between the vibration of a trapped leaf and that of an insect or of a lunging frog; others said they cannot.

Besides walking, an SSFS can run across the water, row across it using several pairs of legs like oars; or glide, pushed by the wind like an iceboat. 

An SSFS is equally at home on dry ground – hunting along its shoreline, on leaves of shoreline plants, and on floating leaves in the water. 

Spiders in the air?  These spiders have been observed jumping up off the water’s surface to snag prey (or to avoid becoming the prey of birds, fish, frogs, snakes, and dragonflies), and they can disperse by ballooning https://uwm.edu/field-station/bug-of-the-week/spider-flight-rerun/.   

SSFSs, like many spiders, are sexually dimorphic; he is half her size.  When a young male’s fancy turns to love, he proceeds with caution, because he is prey-sized and she needs protein to produce yolk for her eggs.  The signals are chemical, vibratory, and tactile.  He may follow her pheromone-laced silk dragline across the water, actually pulling himself along it (her scent is on the water, even without the dragline).  When he finds her, he waves his legs and jerks, and then expresses his further ardor by leg-tapping.  These vibrations produce ripples that spread and reach her.  If she is receptive, she waves, drums her palps (structures near her mouth), and then they spar for a while.  His actions defuse her prey drive – somewhat.  If she does cannibalize him, it increases the chances that her egg sac will hatch.

Experiments have been done to discover why she eats her mate.  Is it merely nutritional (called adaptive foraging – and she may eat him before he becomes a sperm donor) or is it the heat of the moment (aggressive spillover or misplaced aggression)? The results are inconclusive.

Her eggs are placed in a silken case that she totes around with her.  A Wolf spider attaches her egg case to spinnerets at the rear of her body; the SSFS carries them in the front, with her palps.  Nursery web spiders got their name because when her eggs are about to hatch, she builds a silken “nursery web” for the sac, and the spiderlings hatch out within its shelter.  She stays with them for a week or so until they leave the nursery.   It takes young SSFSs two winters to mature enough to perform their risky dance on the water. according to strict Jewish dietary laws, making unfiltered tap water off limits to observant Jews.

Kate Redmond, The BugLady

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

Bug o’the Week – Wetland Homage – Cyclops

Bug o’the Week
by Kate Redmond

Wetland Homage Cyclops

Salutations, BugFans,

May 1st kicks off American Wetlands Month! While we love wetlands year-round, May is a particularly great time to celebrate them as we enjoy the re-awakening of wetlands and all their glorious sights, sounds, and smells.  Let’s kick the month off with the story, from 2013, of a tiny, but very numerous and very important, wetland critter.

The ephemeral pond is humming these days, and the BugLady has been giving her 50mm macro lens a workout, channeling her inner photomicroscopist (a person who takes pictures through a microscope).  A reminder to newer BugFans – the BOTW definition of “bug” is the one that your average first grader uses.

The CYCLOPS is an aquatic non-insect whose name is taken from a character in Classical Greek Mythology (the BugLady trusts that BugFans will dust off the tattered Edith Hamilton Mythology paperbacks they’ve been carting around since high school and will look up the story of Cyclops).  The BugLady has always viewed cyclops as tiny, benign critters that twitch through their watery lives at the very limits of her vision, but it turns out that they have a Dark Side. 

These pear-shaped critters are related to fairy shrimp, daphnia, scuds, sowbugs, and water sowbugs – all of previous BOTW fame.  As crustaceans, they number shrimp, crayfish and lobsters among their distant relatives, too.  The subphylum Crustacea is in the huge Phylum Arthropoda; Arthropoda also includes insects and spiders, and the phylum may account for 80% of known, living species of animals.  Within the Crustacea, cyclops (which is both singular and plural) are in the class Maxillopoda and in the subclass Copepoda (a diverse group comprised of about 13,000 species). 

Cyclops and the rest of their copepod brethren are everywhere on the globe, mainly in calm waters, cold or warm, from the water traps of bromeliads to roadside ditches to underground caves to oceans.  They migrate passively, caught up in the feathers of waterfowl, stuck to aquatic insects that move from pond to pond, or in dust clouds that blow encysted larvae across the landscape from a dried-up pond.  They are among the most numerous of multi-celled animals in any body of water. 

Yes, they are small – the average cyclops needs to stand on tiptoes to reach 2mm.  Though they can scarcely be seen in a basin of pond water, cyclops are instantly recognizable because of their jerky movements and because the female is almost always toting around an egg sac or two. 

They come in a variety of neutral colors, plus transparent (and according to Elsie B. Klots in The New Field Book of Freshwater Life, some species that dwell at pond edges may be bright pink, green or blue in spring).  Like other copepods they have five pairs of legs attached to the thorax, and their heads have mouthparts and two pairs of antennae.  Cyclops have a single black or red eye that distinguishes light from dark (see: Mythology, Cyclops, above).  The antennae are sensory organs, and the first pair is also used in locomotion.  The forked tail is adorned with spines, bristles and hairs that aid in locomotion, balance, feeding, and in sensing the nuances of their environment.  They exchange gases through their body surface and are tolerant of low oxygen concentrations. 

The actions of a number of appendages combine to cause their characteristic gait.  When they begin to row with their five pairs of legs (copepod means “paddle foot”), the antennae are tucked against the body at the start of the leg stroke but are extended at the end of the stroke, which acts to put on the brakes but also helps to keep the tiny critter from sinking (all this in less than 1/12 of a second).  They use the abdomen as a rudder.

About those egg sacs.  While mating, he passes one or more sperm packets to her, enough to fertilize several broods.  Five to 40 eggs hatch inside the egg sacs and the young exit within five days.  The used egg sac is immediately replaced by a new one that fills with new eggs.  The young that hatch from the eggs go through five stages in a form called a nauplius https://en.wikipedia.org/wiki/File:Nauplius_larva_of_a_cyclops_copepod.jpg before assuming a more cyclops-like larval form called a cyclopoid.  Some species pop out little nauplii all summer; some breed just once.  Other kinds of copepods can produce “summer eggs” and then form special thick-walled winter eggs that can withstand harsh environments like the annual drying of an ephemeral pond.  Cyclops don’t have “winter eggs,” but they can aestivate (rest in suspended animation) in drought-resistant cysts or cocoons in one of the pre-adult, cyclopoid stages. 

What fuels cyclops?  Depending on the species, they are powered by plankton and other organic matter, algae or detritus, or by eating animals even tinier than themselves.  Some are parasites.  They form a link in the food chain between the even-tinier algae and bacteria that they consume and the larger plankton predators that are eaten by fish.  One of cyclops’ predators is a plant – carnivorous Bladderworts catch and digest them in underwater bladders that open up when a mini-critter bumps into a trigger hair.  Cyclops are sometimes introduced into aquaria to provide food for fish, but they may reproduce faster than the fish can eat and overrun the tank. 

Bladderwort

And the Dark Side?  Cyclops can be an intermediate host to some pretty nasty parasites including the Guinea worm in Africa and Asia, a fish tapeworm that makes eating sushi and ceviche a potentially risky business, and a roundworm in Asian countries that can infect humans with a condition with the awesome name of gnathostomiasis (the Asian swamp eel that is the main host for this nematode has found its way to the Americas, so the stage is set).  There’s a link between copepods and cholera in some tropical countries – the cholera germ hitches a ride on the tiny, swimming critters.

Interesting cyclops fact – Cyclops are present in the water supply of some large American cities, where routine treatment renders them harmless (dead) but does not filter them from the system.  As crustaceans, they are not kosher according to strict Jewish dietary laws, making unfiltered tap water off limits to observant Jews.

Kate Redmond, The BugLady

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

Bug o’the Week – European WoolCarder Bee

Bug o’the Week
by Kate Redmond

European WoolCarder Bee

Howdy, BugFans,

Today’s bug is a world traveler, and the pictures shared by BugFan Freda were taken far from our shores.  Thanks, Freda!

So, no guesswork about the geographical origin of the European Wool Carder Bee (Anthidium manicatum) (in the Old World, it’s also found in Western Asia and Africa).  The EWCB was first recorded in North America in 1963, near Ithaca, NY (three years before the BugLady got there), was seen in California in 2007, and is now established in a large chunk of the US and Canada.  Its nesting habits make it eminently portable, and it has also made its way to parts of South America, New Zealand (2006), and more https://www.discoverlife.org/mp/20m?kind=Anthidium+manicatum.

Look for it in grasslands, road edges, and gardens, where it often visits flowers of European origin, especially if they’re blue.

EWCBs are in the family Megachilidae, the Leafcutter, Resin, Mortar, Sharptail, Mason, and Woolcarder bees.  Not all woolcarder bees come from elsewhere – there are a total of 170 WCB species in the genus Anthidium worldwide, including 29 in North America.  “Carder?”  Females harvest hairs (trichomes) from fuzzy plants to use in the construction of egg chambers – more about that in a sec.   

These are chunky, hairy, honey bee-sized bees that are colored like yellowjackets and that can hover like Syrphid/flower/hover flies.  Males are larger than females, and the last two segments of the males’ abdomen have a spine on each side, plus a fifth spine at the very tip.  Like other members of the family, their pollen-carrying hairs (scopae) are under their abdomen rather than on their legs https://www.bugguide.net/node/view/1099969/bgimage.  Much of the face is yellow, and there are variable yellow bands on the abdomen, a few yellow spots around the edges of the thorax, and yellow patches on the legs.   

One source said that most bees can’t be ID’d on flower tops at a glance, but this one can.  The moral of that story is, as always, that the BugLady needs to pay way more attention to the bees she sees.   

They feed on pollen from a wide variety of often blue, often hairy, often “long-throated,” often sun-loving, and often non-native flowers (the BugLady is trying to picture the Venn diagram).  In New Zealand, non-native flowers are their top choices.  Their generalist feeding habits explain their success in establishing themselves around the world.

Males are territorial and aggressive, staking out patches of flowers and defending them against other WCBs and just about any flying insects, including bumble bees – plus hummingbirds and even humans.  With rival bees they take the direct approach, flying up to them and trying to knock them off the flower.  The encounter may escalate, with the territorial male chasing the intruder, biting it, and even using the spines on his abdomen to get the message across.  Although they are equipped to do damage to rival males, competitions generally end with the territory owner routing the intruder, not harming it.  One source wrote that males may have 70 hostile encounters in an hour; thus, they’ve earned the name “Bossy/Bully bee.”   

The system selects for larger males – larger males tend to hold territories and to win territorial disputes, and females prefer them.  Itinerant males tend to be smaller.

If a female enters his territory to forage, she is expected to mate with him if she wants access to pollen (convenience polyandry).  As a result, both males and females mate multiple times.

These are solitary rather than colonial bees.  Females locate a preexisting, above-ground cavity to house their nest – a crack in a wall or foundation, rotting wood, a knothole, a plant stem, a bee hotel (which can be great fun, but strict hygiene must be maintained).  Then they visit fuzzy plants https://www.bugguide.net/node/view/1696859/bgimage, scrape hairs off of leaves or stems with their toothed mandibles, and form it into balls.  They carry it under their bodies to the nest, where they use the hairs to fashion the walls and partitions of brood cells https://www.bugguide.net/node/view/421614/bgref.  

Some of the hairs she collects are “hydrophobic” – that is, they resist water, which helps keep the chambers (and their inhabitants) dry and microbe-resistant.  Some trichomes are glandular, and as she collects the plant hairs, her legs are exposed to their secretions.  These she rubs onto the cells as she builds (but the BugLady was unable to discover the benefits of doing so).  She may also incorporate mud, leaves, or resin.    

Each egg cell contains pollen and nectar (usually from mints like Salvia and Stachys), and the female lays an egg on the food pile in each cell before she seals it.  When she has made enough cells in a cavity, she closes it with a plug.  When the eggs hatch, the larvae consume the food Mom has left, pupate, and emerge later in summer.  If there are two generations per year, the second generation overwinters as dormant larvae in the cell, to resume growth and emerge in late spring.

A plant that’s mentioned frequently with EWCBs is Lamb’s ear (Stachys byzantina), a common flower garden plant.  Researchers found that, like many plants, Lamb’s ear releases volatile organic compounds (VOCs) when its vegetation is disturbed – in this case, when its trichomes are harvested, and these VOCs are different than the VOC bouquet emitted by the intact leaves.  The bees sense the VOCs, but instead of avoiding plants where hairs had already been harvested, the VOCs attracted them to trim more.  It was suggested that these VOCs acted to help EWCBs to identify target plants more easily.

Opinions are mixed about their impact on native bees, and some people list them as invasive.  Yes, EWCBs are great pollinators, but they use the same nest sites as native bees, and they’re competing aggressively with them for the same flowers.  And they may be pollinating the “wrong” plants. 

Kate Redmond, The BugLady

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

Bug o’the Week – Whitebanded Crab Spider

Bug o’the Week
by Kate Redmond

Whitebanded Crab Spider

Greetings, BugFans,

The BugLady loves crab spiders, so she’s been thrilled to find two, new (to her) species in the last few years.  One, the Whitebanded crab spider, is in the family Thomisidae, a family of, well, crab-shaped spiders, many of whom make their living on flower tops, and many of whom, in the genera Misumena, Misumenoides, and Misumenops (Mecaphesa), can be tricky to ID.  We’ll meet the other one next week.

Whitebanded crab spiders (Misumenoides formosipes) (formosipes is from the Latin for “beautiful leg/foot”) are named for a white band that crosses their face, right below the level of the eyes https://www.bugguide.net/node/view/1295835/bgimage (depending, of course, on whether the spider is right-side-up or up-side-down).  But there’s a catch.  Like the very common Goldenrod crab spider (Misumena viata), female WBCSs can change colors depending on where they’re sitting – from white to yellow and back – by secreting or excreting yellow pigment from their normally-white outer cell layer (cuticle).  Turning yellow takes longer – up to three weeks – than does reverting to white.  In its yellow form, it could be called the Yellow-banded crab spider https://www.bugguide.net/node/view/2058436/bgimage.  Other common names include Red banded crab spider and Ridge-faced flower spider.

They’re widespread, found in Ontario and much of the US, excepting the Northwest quadrant.   

WBCSs have eight eyes – four are arranged in a straight line, two are above that, and the other two are around the edges.  As is common in spiders, females are much larger than males https://www.bugguide.net/node/view/89420, and they have dark markings on their legs, which separates them from some of the other genera of flower crab spiders.  Females come in a variety of colors https://www.bugguide.net/node/view/35697, https://www.bugguide.net/node/view/6516, and https://www.bugguide.net/node/view/327244.  Males typically have a red/orange/gold abdomen, and their four front legs are dark https://www.bugguide.net/node/view/577576/bgimage, but they can’t switch colors.

WBCSs don’t make trap webs; they’re ambush predators that hang out on flowers and attempt to grab any visitor to the flower that looks toothsome, even if it’s slightly larger than they are.  They are frequently collected by various mud dauber wasps – stung, paralyzed, and used to provision the wasp’s egg chambers – food for eventual wasp larvae.  Spider eggs and spiderlings provide food for lots of predators. 

Males, especially when they are actively hunting for a mate, are nectivores, feeding on pollen and nectar, especially on Queen Anne’s lace.  Searching for a mate takes up a good deal of a male’s time, so he employs a “Bird in the Hand” strategy.  He locates a female before she becomes fully mature (unmated penultimate female), and he guards her until she is old enough to reproduce.  He lives on her inflorescence and takes on rival males, but despite his devotion – and energy investment – whichever male is closest after she undergoes her final molt will likely be the lucky spider, although the resident male does have the home-field advantage. 

Female WBCSs like Black-eyed Susans, and males search for likely flowers by their smells.   His small size and light weight allow him to jump from one flower head to another or to loose a line of web into the wind and to tightrope across it after it sticks to the next flower.

Females create silk sacs holding 80 to 180 eggs, attach them to leaves, and guard them until she eventually freezes.  The spiderlings exit the egg sac in spring. 

Yes – they do eat pollinators, and everyone loves pollinators.  But these are native spiders feeding on native pollinators, and they worked all that out a long time ago – their food habits don’t upset the Balance of Nature, and they supply protein for larger critters.  Some apologists point to the fact that the presence of predators improves the defenses of prey species over time. 

Go outside, look for bugs!  The BugLady visited a wetland on a warm day recently and saw some Common Green Darners messing around in a stand of last year’s cattails.

Kate Redmond, The BugLady

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

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