Field Station /field-station/ UW-Milwaukee Wed, 15 Apr 2026 13:28:35 +0000 en-US hourly 1 https://wordpress.org/?v=6.9.4 Whitebanded Crab Spider /field-station/bug-of-the-week/whitebanded-crab-spider/ Wed, 15 Apr 2026 13:28:15 +0000 /field-station/?p=17045 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 …

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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 generaMisumena, Misumenoides, and Misumenops(Mecaphesa), can be tricky to ID. We’ll meet the other one next week.

Whitebanded crab spiders (Misumenoides formosipes) (formosipesis from the Latin for “beautiful leg/foot”) are named for a white band that crosses their face, right below the level of the eyes (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 .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, 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 , , and .Males typically have a red/orange/gold abdomen, and their four front legs are dark , 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.

The BugLady

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Pussy willow Pollinators /field-station/bug-of-the-week/pussy-willow-pollinators-2/ Wed, 08 Apr 2026 16:36:37 +0000 /field-station/?p=17020 Salutations, BugFans, 2026: The pussy willows near the BugLady’s lakeshore home are in bloom.Here’s a BOTW about pussy willows from late March of 2012 – a few new words and pictures. 2012:People get excited when pussy willows whisper the spring.The …

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Salutations, BugFans,

2026: The pussy willows near the BugLady’s lakeshore home are in bloom.Here’s a BOTW about pussy willows from late March of 2012 – a few new words and pictures.

2012:People get excited when pussy willows whisper the spring.The BugLady loves skulking among them when they’re blooming, ogling the diversity of insects that come to visit when very few other flowers are out.Willows aredioecious(separate house), bearing their male and female flowers on separate plants.The gray, fuzzy buds are future male flowers that will morph into catkins bearing long, slender filaments (pollen-producing stamens).The thicker, “caterpillar-like” flowers – fleshier stalks with what looks like a tiny flower at the tip, are future female catkins and seeds.Pussy willow (Salix discolor), which is a prodigious pollen producer, is almost finished blooming, but other willow species are still in bud.

Remember that pollination is an accidental service performed by animals that visit the pussy willows for another purpose altogether – to perch, to set up housekeeping, to browse an important, early food source (the male flowers produce a little nectar and a lot of pollen, and female flowers supply nectar), or to browse the browsers.Mining bees and syrphid flies made up the majority of the insects that the BugLady saw, with flies (blow, flesh, and house) next.The BugLady also saw a spring azure butterfly checking out the willow flowers.

For all their attractiveness and importance to these early pollinators, pussy willows are largely wind-pollinated.Wind-pollinated flowers produce massive amounts of pollen because wind pollination is pretty random.

The BugLady found:

ANTS– Ants become active when the spring sun warms the soil they nest in. If you put all of the people on the globe at one end of a teeter totter and all the ants on the other, our feet would be dangling. There are many kinds of ants with many lifestyles and many diets.

Ant crawling among willow catkin filaments

ASCLERA RUFICOLLIS– Adult Red-necked false blister beetles feed on early spring flowers in woods and wood edges; their larvae dwell in rotting logs.Apparently, despite its name, a crushed false blister beetle produces highly irritating chemicals that will make a (false?) blister.

Red-necked beetle dusted with pollen on willow

BROWN STINKBUG– Some species of brown stinkbug are vegetarians, but the BugLady thinks that this is one of the predatory stinkbugs.The BugLady wonders if the heavy dusting of willow pollen works as an inadvertent disguise.

Brown stink bug covered in yellow pollen on twig

CAROPHILUS BEETLE – A sap beetle – although most sap beetles are consumers of rotting fruits and vegetables and fungi, some are found on flowers.

Small sap beetles inside willow catkin

DISONYCHABEETLE– The very spiffy Striped willow leaf beetle is in the huge leaf beetle family Chrysomelidae.Members of the small genusDisonycha(according to one source) mostly eat “weeds.”This one eats willow-parts.

Striped leaf beetle on colorful willow catkin

GREENBOTTLE FLY– These members of the Blow fly family are listed as carrion feeders. Apparently, this fly was cleansing its palette.

Green bottle fly on willow flower

CYNOMA CADAVERINA – Another member of the Blow fly family, with a decidedly un-wholesome name, stared at the BugLady from a willow branch. The BugLady moved on down the trail.

Cluster fly perched on branch

HONEYBEE– an important – and imported – pollinator, honeybees are on the landscape starting in late winter and early spring.Bees foraging for pollen near wetlands may warm up within the insulated comfort of a skunk cabbage spathe, which may be 30 degrees warmer than the ambient temperature.

Honeybee collecting nectar from willow bloom

MINING BEE– Mining bees are a mainly solitary bunch of bees; females stock brood cells with pollen and nectar for their emerging young.They are important early, native pollinators.

Pollen-covered mining bee on yellow willow flowers

SWEAT BEE – Sweat bees collect prodigious loads of pollen and transport it to their underground nests. Most are solitary; a few are marginally social.”

Metallic green sweat bee on willow catkin

SYRPHID FLY – Syrphid/Hover/Flower flies are bee mimics that feed on nectar and pollen.

Hoverfly feeding on willow flower

SPOOKY TACHINID(probably) – Tachinid flies have an ulterior motive.They lay eggs, or sometimes live young, on flowers so that their young may board another insect and become a parasitoid.The BugLady thought this ghost-colored tachinid was a bit creepy-looking.

Tachinid fly resting on willow bud

NOMADA WASP – The BugLady is amazed at the antennae on this Nomada wasp.

Nomada cuckoo wasp on willow blossoms

EUROPEAN PAPER WASP – Negotiating the thicket of flower parts on the male flower must be a challenge.

Paper wasp feeding on willow catkins

Go outside and watch the willows!

The BugLady

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Brush-tipped Emerald /field-station/bug-of-the-week/brush-tipped-emerald/ Wed, 01 Apr 2026 13:48:29 +0000 /field-station/?p=17009 Greetings, BugFans, Dragonflies!But not soon enough! Quick and dirty dragonfly phenology (phenology – the study of Mother Nature’s calendar.Cliff notes version – things appear/bloom/disappear/migrate in pretty much the same order every year, we just can’t predict the start date). Common …

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Greetings, BugFans,

Dragonflies!But not soon enough!

Quick and dirty dragonfly phenology (phenology – the study of Mother Nature’s calendar.Cliff notes version – things appear/bloom/disappear/migrate in pretty much the same order every year, we just can’t predict the start date). Common Green Darners lead the parade, their arrival from the south governed by temperature and by the same weather fronts that bring migratory birds north (coinciding, hopefully, with the emergence of some insect prey for both).Migrating Variegated Meadowhawks show up in early May – or they don’t.The next tier, usually airborne by mid-May, includes Common Baskettails, Common Whitetails, Chalk-fronted Corporals, Four-spotted Skimmers, and the aptly-named Springtime Darners.

Brush-tipped Emeralds (Somatochlora walshii) are summer dragonflies. 

Brush-tipped Emerald dragonfly in flight with iridescent green eyes and transparent wings

They’re in the Emerald family (Corduliidae), represented in Wisconsin by the baskettails, shadowdragons, boghaunters, a couple of smaller emeralds (Racket-tailed and American), and thirteen members of the genusSomatochlora, the Striped or Green-eyed Emeralds (). Somatochloracomes from the Greek for “green body.”Emeralds are called emeralds because in many species, the adults, especially the adult males, have emerald-green eyes.The BugLady can testify that when you’re walking down the trail with the sun at your back and you encounter an emerald that’s flying toward you, the glow of those eyes is a religious experience !The most famous emerald here in God’s Country is the Federally Endangered Hine’s Emerald Hine’s Emerald Dragonfly—the Backstory – Field Station.

The Striped emeralds are, as the Wisconsin Odonata Survey website points out“uncommonly seen, but this may be largely due to their secretive nature.”It goes on to say that “the medium-sized, dark brown striped emeralds have some pale markings on the thorax and abdomen, black legs, clear wings and brilliant green eyes. The thorax has a metallic bronze-green sheen and the abdomen is dark metallic black-green.”While some species live in the South, many are dragonflies of the North country, even living above the treeline.

Look for Brush-tipped Emeralds near bogs, fens, marshes, and lake outlets, near slow streams, and over meadows and at the edges of coniferous woods in Canada and across the northern tier of the US (though small populations are found at higher elevations in the Appalachians). 

Emerald species are hard to tell apart in flight, but male Brush-tipped Emeralds have, well, a brushy tip that can be imagined as it flies by – as Kurt Mead says inDragonflies of the North Woods,“the whiskered tips of the male Brush-tipped’s abdominal appendages are unlike those of any other North American species”ofSomatochlora“ (though the appendages of other species are not hairless). If they sit still long enough, you can see that the metallic-green abdomen has pale yellow spots that can help narrow down the identification.Adult Brush-tipped Emeralds are about two inches long; males have short abdomens and females have proportionately longer abdomens than males.

Brush-tipped Emerald dragonfly partially hidden on a vertical stem in wetland habitat

Males are strong flyers, patrolling territories by flying low (less than three feet off the ground) along the edges of cool-water wetlands, abdomen arched, putting on aerial displays, chasing rivals, and looking for females.Females lack the kind of ovipositor that would allow them to insert eggs into a plant stem, so they locate an area with lots of floating-leaved and submerged aquatic plants and they fly slowly, close to the water’s surface, dipping into or tapping it with the tip of their abdomen to release eggs (200 to 500 in all).When the eggs hatch, the naiads hide in the vegetation. They sometimes oviposit into muck or wet moss.

The BugLady got some Hail Mary shots of a female Brush-tipped Emerald (probably) who was considering a small lake inlet for ovipositing.

Adults hawk small, soft-bodied, easy-to-eat insects from the air (including mosquitoes) and consume them in flight.Females fly above small woody clearings and along roads and trails.They may forage for food away from water, but they remain attached to their natal wetland.The naiads ambush any aquatic critters they can, including tiny tadpoles and fish, and they’re preyed on by bigger aquatic insects, fish, and frogs.Spiders and birds catch the adults.

The BugLady

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Monarch Butterflies – Spring, 2026 /field-station/bug-of-the-week/monarch-butterflies-spring-2026/ Wed, 25 Mar 2026 14:07:00 +0000 /field-station/?p=17002 Howdy, BugFans, THEY’RE COMING!!! It’s barely spring, officially – way too early to be thinking about butterflies, right?Nope.The first butterflies of the year have already been reported on the Wisconsin Butterflies website (Butterflies — wisconsinbutterflies.org) (which also serves your Tiger …

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Howdy, BugFans,

THEY’RE COMING!!!

It’s barely spring, officially – way too early to be thinking about butterflies, right?Nope.The first butterflies of the year have already been reported on the Wisconsin Butterflies website () (which also serves your Tiger beetle and Robber fly needs).

Our first butterflies are usually the anglewings (commas and Question Marks Anglewings (Family Nymphalidae) – Field Station) and the Mourning Cloaks Mourning Cloak Revisited – Field Station.Why?Because they go through the winter as adults, tucked up into a sheltered spot (called a hibernaculum).These are the species that are seen by people tapping maple trees in the Sugarbush during the warm days of late winter.When the cold returns – and it always does, except in the bizarre spring of 2012 – they seek shelter again.They are able to be abroad in early spring, before the wildflowers bloom, because they feed on sap from sap drips, juice from rotting fruits, and minerals from animal droppings.

The other early butterflies are species that overwintered as a chrysalis and emerged in spring – Cabbage Butterflies Cabbage Whites and Sulphurs Redux – Field Station and a couple of “blue” butterflies, the Eastern Tailed-Blue and the “Spring” Spring Azure Small Blue Butterflies – Field Station.In very warm years, early individuals of these species have been recorded in late March.Our first Monarch sightings usually come in May.

Back to the Monarchs. A year ago, winter censuses of the eastern and western populations, Monarch Butterfly showed that numbers were down The Monarch Butterfly Problem – Field Station. This year’s census found eastern Monarchs occupying 64% more territory in Mexico’s oyamel fir forests than last year.Not a home run, but reason for optimism .

Monarchs are on the way! Check the Journey North interactive map –.For more information, see .

Monarch caterpillar with black, white, and yellow stripes feeding on a green milkweed leaf

Mike Reese has built a wonderful community of butterfly-lovers who make reports to the Wisconsin Butterflies website; and while it is more anonymous, the Wisconsin Odonata Survey website () contains a treasure trove of information.Where do all those reports come from?Us – they are two examples of Citizen/Community Science projects here in Wisconsin!Register with the site, keep track of the butterflies and/or dragonflies/damselflies you see on your walks or in your back yard (you need to take a nose count of the butterflies but not of the dragonflies), and then log on to record what you’ve seen. Both sites accept pictures.

The Journey North organization offers another Community Science project called the monarch larva monitoring project.

Go outside – look for butterflies!

The BugLady

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Common Green Darner rerun /field-station/bug-of-the-week/common-green-darner-rerun/ Wed, 18 Mar 2026 14:27:53 +0000 /field-station/?p=16984 Salutations, BugFans, 2026 The BugLady checked the (highly searchable) website of the Wisconsin Odonata Survey (Wisconsin Odonata Survey) to see if anyone had reported a Common Green Darner yet.They are early migrants from the southeastern part of the country, traveling …

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Salutations, BugFans,

2026

The BugLady checked the (highly searchable) website of the Wisconsin Odonata Survey () to see if anyone had reported a Common Green Darner yet.They are early migrants from the southeastern part of the country, traveling north with the warm weather, and they’re often the first dragonfly species of the year.Here’s an episode about them from nine years ago.New pictures, a few new words.

2017

A Common Green Darner was reported near La Crosse (WI) on March 24 of this year, and a few others have been seen since then (and even though the winter of 2016-17 has been “Winter Lite,” the BugLady is ready for spring and dragonflies). The BugLady wrote very brief biographies of the green darner in 2010, in BOTWs about spring dragonflies and about dragonfly swarms, but there’s much more to the Common Green Darner story.

They are in the darner family Aeshnidae, a group of large, powerful dragonflies (“darner” because their long, darning needle-like abdomen has led to folk tales about their sewing people’s lips or ears shut). 

Most of our Wisconsin darners are in the famously-confusing mosaic darner genusAeshna.Common Green Darners (Anax junia) (“Lord of June”) are one of two species ofAnaxdarners found in the state.Common Green Darnersare, well, very common, not just here but across the country.And Central America. And Hawai’i.And Canada. And there are populations in Tahiti and the West Indies.And strong winds have blown individuals to Great Britain, China, and Russia.The otherAnax, the stunning Comet Darner (Anax longipes) is a rare visitor and even rarer breeder in Wisconsin .

Male Common Green Darner with bright blue abdomen on plant stem

Common Green Darners are big, with a 3” long body and a 3 ½” wingspan, and their striking “wrap-around” compound eyes may be made up of as many as 50,000 simple eyes apiece.Their wings often show a golden tinge in flight. They practice sexual dimorphism – both males and females have a green thorax, but males have a predominantly blue abdomen with a purple stripe, and females have a maroon/rust-colored abdomen with a darker stripe.Tenerals (newly-emerged adults) may take a week or more to solidify their adult color patterns and have female-ish coloration in the interim, and a chilly darner is a darker-colored darner.Both males and females have prominent cerci (claspers) at the abdomen’s tip.Common Green Darners have a characteristic bull’s-eye spot on their “forehead” that Comet Darners lack. They can move each wing independently, which lets them hover, and even fly backwards.They perch vertically, frequently in low vegetation, so they usually spot the BugLady long before she spots them.

Female Common Green Darner with reddish abdomen perched on grass

The long, slim, immature green darners (naiads) are found in still orveryslowly-moving, shallow waters, preferably without sunfish and bass (nice set of naiad pictures here ).Adults frequent the air above those habitats but may be seen far from water.

Close-up of Common Green Darner head showing large compound eyes

Two populations of common green darners – one migratory, the other resident – form tag teams in the air over Wisconsin.Migrants from the south arrive early, often in late April, as their prey (small, aerial insects) start to appear. They are the offspring, or the offspring’s offspring, of the darners that flew south in the fall (no, they apparently do not return to their natal ponds). “Shivering” their wing muscles to heat up the thorax allows them to be active in cool weather, and they also bask in the sun. This is so effective that temperatures as high as 110 degrees have been measured inside the thorax (which challenges the whole definition of cold-bloodedness).The picture of the female with the battered wings was taken in early July, suggesting that she was a migratory female who was reaching the end of her trail.

Common Green Darner exuvia clinging to plant stem after emergence

The migrants mate and die by early summer, leaving their eggs in the water, just as the naiads of the resident population emerge as adults, leaving their empty shells (exuviae) on shoreline vegetation.These residents live a month or two as adults, depositing their eggs in late summer as the migrant adults emerge.Resident naiads overwinter under the ice in a state of suspended animation calleddiapauseand take 10 or 11 months to mature (possibly more, in the chilly waters “Up North”), while the migrant naiads need less than half that time in the warm waters of summer.

Pair of Common Green Darners in tandem laying eggs on water plants

Mating commences when a male clasps a female at the back of her head in mid-air (one source said that she can reject his advances), and then they retire to a perch to mate.Females oviposit in the open, in woody and herbaceous plant material below the water’s surface, with the male typically retaining his grip on her head.

The books say that these are the only darners that oviposit in tandem.The books also say that a couple flying in tandem may be strafed by rival males.The attendant male doesn’t have many options; he may flap his wings at the intruder, shake his abdomen, land in vegetation, and even bite his challenger.According to Paulson, inDragonflies and Damselflies of the East, females may curl their abdomen under and close their wings when under attack.The BugLady once photographed (badly) an unattached male as he dive-bombed a second male whose abdomen was deeply submerged (presumably with an ovipositing female at the other end of it).

Common Green Darner trapped in algae with wings spread

The BugLady once found a female stuck in an especially dense and sticky, dragonfly-eating patch of blanket algae.Did the female attempt to perch on the algae as she oviposited and get her wings stuck, only to be abandoned by her mate?Or, alternatively, did she get thirsty and then get stuck?Dragonflies “drink” by immersing their abdomen – water enters through the exoskeleton (the BugLady was able to fish her out with a stick).

The naiads are active predators that will eat anything they can grab using their foldable “lower lip” (labium) – zooplankton, other aquatic insects (including dragonfly naiads), tadpoles, larval salamanders, and fish fry are all fair game.In his wonderful write-up of the Common Green Darner, Kurt Mead (Dragonflies of the North Woods) muses that “If dragonfly larvae were eight to sixteen inches long, as they probably were 300 million years ago, we would dare not swim in fresh water for fear of being attacked” (read the whole account at ) (there was a lot of oxygen in the atmosphere in those days, and some invertebrates grew to lunker size). Despite their spiny exteriors and their ability to shoot forward by expelling a spurt of water forcefully from the rear of their abdomen, they are eaten by frogs, fish, and by other aquatic insects. There’s even an “aquatic” parasitic wasp that lays its eggs in those of the green darner –Aprostocetus polynemaeapparently walks down a twig or leaf stem into the water to find dragonfly eggs.

Adults catch insects in the air and may eat them in mid-flight or on a perch.They can also pick prey from a leaf or from the ground, and they’ve been known to stake out bee hives, to the distress of the bee-keeper.At least one ambitious Common Green Darner killed a hummingbird, and this fact is mentioned in every darner write-up, though the BugLady suspects it’s pretty uncommon. Adults are preyed on by robber flies, birds, spiders, and by other dragonflies; the people who monitor the fall raptor migration tell us that the southward movement of American Kestrels syncs with that of the darners, and that kestrel migration is fueled by darners.

Common Green Darner flying over water with wings extended

So, Common Green Darners migrate. Like birds, they respond to a suitable weather front – cold fronts for the southern flight and warm fronts for the far less conspicuous northern trip.The journey south may take several weeks of stop-and-start flying (averaging 7 miles a day but capable of far more, depending on the wind), and they may be accompanied by black saddlebags and variegated meadowhawk dragonflies.Late summer/fall migration is dramatic, huge swarms may take hours or days to pass a fixed point.Bluffs on the west edge of Lake Michigan are great places to catch the show at eye level.

The Common Green Darner is the State Insect of Washington – so much more exciting than Wisconsin’s honeybee (and you thought the state insect was the mosquito!).

As always, don’t eat them – they carry parasites.

Unfinished business – in response to the recent BOTW about deer flies, a few French scholars pointed out to the BugLady that she had misspelled the term “je ne sais quoi” as “jean es se qua.”She had consulted Monsieur Google about the correct spelling, and she had, alas, believed him.

The BugLady 

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Deer Fly at Last /field-station/bug-of-the-week/deer-fly-at-last/ Wed, 11 Mar 2026 14:42:07 +0000 /field-station/?p=16973 Howdy, BugFans, Way back in 2008, deer flies appeared briefly (two paragraphs) in a BOTW episode called “A few Flies,” sharing the spotlight with mosquitoes and horse flies. Amazingly, that’s the only time deer flies have appeared in BOTW, and …

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Howdy, BugFans,

Way back in 2008, deer flies appeared briefly (two paragraphs) in a BOTW episode called “A few Flies,” sharing the spotlight with mosquitoes and horse flies. Amazingly, that’s the only time deer flies have appeared in BOTW, and it’s past time to flesh out their story.

Deer flies are in the family Tabanidae, the horse and deer flies, and they’re in the subfamily Chrysopsinae, the deer/sheep/yellow flies (although one source says that they should be called “human flies”). There are 120 species of deer flies in North America, with more abroad, and a combined total of 30 species of horse and deer flies live in Wisconsin (lots of write-ups treat deer and horse flies together, because their life stories are similar).

They are found worldwide, and although the fast-flying adults may wander away from them, they are tied to wetlands because their larvae grow up in the water or in adjacent, damp soils. Adults can also be found patrolling sun-dappled woodlands and edges.

deer fly on leaf

How do you know you’re looking at a deer fly?There are some scientific/microscopic measurements involved, but in general, deer flies are smaller than horse flies but larger than house flies, and many have yellow and black-striped bodies, wings with pigmented splotches on them, colorful eyes that are adapted to function well in the bright sun of late spring and early summer, and noticeable mouthparts.

deer fly mouthparts close-up

Famously/infamously, deer flies use those mouthparts to bite people and other mammals.Only the females bite – she needs the blood to facilitate the development of her eggs.Males are vegetarians who use their mouthparts to take nectar and pollen from flowers (she will also feed on nectar and pollen when she’s not in egg-laying mode).The female’s mouthparts are described as “scissor like” – she uses them to make an x-shaped cut, and then she laps up the resulting blood, keeping it flowing with anticoagulants in her saliva.Deer fly larvae are mainly carnivores that clean up on smaller invertebrates they find in water or moist soil.

deer fly biting skin

Deer fly larvae are eaten by larger, aquatic carnivores like fish, predaceous diving beetles, and dragonfly naiads, and the adults fall prey to toads, killdeer, aerial insectivores like flycatchers and swallows, and dragonflies, and to wasps and hornets looking to stash them in their egg chambers as food for their eventual offspring. 

Science word of the Day: deer flies are “hydrobionts,” which means they need wet areas in order to reproduce. The dance may start with a breeding swarm where boy meets/pursues girl (in most species, the boys hatch out a couple of days before the girls). What starts in the air is consummated on the ground, and then females go looking for a blood meal before tucking masses of 100-plus eggs onto vegetation near/over water.When the eggs hatch, the larvae (which come equipped with a “hatching spine” that helps facilitate their exit) drop into the water or onto damp soil. They may take more than a year to mature, depending on the size of the adults.

While she was doing her research, BugLady came across a few “Where are the deer flies this year?” articles (not that anyone was complaining). One attributed the low number of flies in their area to a very wet summer that flooded the breeding areas, and the other to a very dry summer that shrank the breeding areas. Deer fly pupae crawl up on plant stems or moist wetland edges just before they emerge, so too much or too little water can affect them.One article asked why there were so many deer flies that year, and the answer circled back to a wet spring and a hot summer (apparently, when it comes to precipitation, deer flies are like Mama Bear).Happily, they aren’t on the scene long – if mosquito season is a marathon; deer fly season is a sprint.

Much has been written about a female mosquito’s use of our individual cocktail of odors as she zeros in on potential targets – that personaljean es se quathat’s made up of our CO2,sweat, fruity-smelling shampoo, and scented laundry detergent, deodorant, and hand lotion (it’s difficult to be unscented in the 21stcentury).But deer flies hunt largely by eye, stimulated by the sight of large, dark, warm, moving objects (including cars), so the repellants that deter mosquitoes don’t work on deer flies. The good news is that although a number of microbes have been identified in a deer fly’s “mouth,” there’s only one disease they are known to transmit in North America – tularemia (aka rabbit fever) is spread by deer flies in the western US.

deer fly on human skin

The pain from a deer fly’s bite is in bee sting territory (it’s been described as “poking a red-hot needle into your skin”).Her saliva may cause further pain and itching, and some people are allergic to deer fly bites.If DEET won’t do it, what will?Dressing for success helps, in light-colored, loose-fitting long sleeves, long pants, and a hat (because when deer flies check us out, they start at the top), and some folks add mesh netting over the cap.Some swear that deer flies are attracted to the color blue.Several sources promised that deer flies are inactive at temperatures under 70 degrees F, but others laughed at that notion.

People have gotten pretty creative in aid of avoiding deer flies, using devices that are homemade and store-bought, sacred and profane, and just plain embarrassing.Sticky patches to attach to your hat, and hats with built-in sticky patches are easy to find in sporting goods stores (see picture ), or you can DIY with loops of duct tape.One author wrote of spreading sticky stuff like Tanglefoot on a cup (think red or blue 16 oz Solo cup) and taping the cup to the top of his hat on his walks.

The BugLady wears a hat on her perambulations, and she enjoys listening to the deer flies bouncing off of it. 

Here are a few gems that the BugLady found while she was Googling.

From the Missouri Department of Conservation:

“In the 1800s, the upland prairies of Missouri’s Audrain County were late to be settled in large part due to the presence of these insects. The WPA-produced Missouri: A Guide to the “Show-Me” State (1941) put it this way: ‘At certain times of the year, the flies made day travel impossible, and even plowing and other farm work had to be done at night.’ Many other prairie regions in the American Midwest had similar problems with tabanid flies; in some cases, horses were said to be driven mad by the incessant attacks of horse and deer flies.”

From the Audubon Beidler Forest website:

If you were to ask me which cloud of biting insects I would prefer, mosquitoes or deer flies? Well, you can outrun mosquitoes. Running away from deer flies just gets them excited.

A deer fly is also characterized by its ability to withstand a fairly good smack after it lands on a person and begins to bite. Often the fly falls lifelessly to the ground after being struck, yet within a few seconds uprights itself and then eventually takes to the air again in an attempt to make another attack.”

From Michigan State University Extension:

Deer flies “apparently have their place in U.S. history: Ross Arnett, author of , reports the following. ‘It is said the Declaration of Independence was signed by July 4, 1776 instead of a later date that would have permitted further discussion because the horse flies in Philadelphia were biting so fiercely at the time that the delegates decided to adjourn just to get away from them.’ĝ

And finally, from “the World Around Us” podcast and blog, which “seeks to arouse your sense of wonder and motivate you to act on behalf of nature at every opportunity.”:

Blogger Sarah O’Malley reminds us that every organism has a job to do, and that deer flies do theirs very well.She concludes that, “No body likes hanging out with deer flies. But all the same, I prefer a world where they exist, a world as full as it can be with as many different kinds of organisms as possible, a world rich and damp and squirming with life. That is truly the point of it all, and we can’t do it without the biters and scratcher anymore than we can do without the cute furry babies and the fluffy little birds. They all count, every last knife like mouthpart wielding one.”

Thanks to BugFan Sophie for taking the picture of the cute little deer fly on the BugLady’s hat.

deer fly on hat fabric

The BugLady

PS – BOTW was born (as a joke) back in August of 2007.What with the reruns and the time-outs, it’s taken a while to get here, but this is, by the BugLady’s count, episode #800. Thanks, BugFan Patrick – and we’re both still going strong! (-ish)

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Golden Silk Orb Weaver – A Snowbird Special /field-station/bug-of-the-week/golden-silk-orb-weaver-a-snowbird-special/ Wed, 04 Mar 2026 14:39:15 +0000 /field-station/?p=16966 Howdy BugFans, It’s almost time for Snowbirds to head back north to rejoin us here in God’s Country for the final days/weeks/months of winter. The BugLady read recently that the number of days below freezing in March here in God’s …

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Howdy BugFans,

It’s almost time for Snowbirds to head back north to rejoin us here in God’s Country for the final days/weeks/months of winter. The BugLady read recently that the number of days below freezing in March here in God’s Country hasdrasticallydecreased in the past 25 years, and March is increasingly considered a spring month rather than a winter month (but when the BugLady was a kid……..). The temperature may be moderating, but March still has plenty of tricks up her sleeve, and most of them involve snow.

BugFan Tom supplied the pictures of this big, beautiful spider that inhabits the South from Virginia to Texas (and beyond, to Argentina and Peru).Thanks, Tom.

Female golden silk orb-weaver on web

The brightly-patterned females may be more than two inches long with a five-inch leg span, (males are much smaller ). A spider this big (probably our largest orb weaver) that makes big webs necessarily gets noticed and collects lots of names, like Banana Spider, Golden Orb Weaver, Calico Spider, Golden Silk Spider, and Giant golden Orbweaver, and people who walk into the webs while hiking probably have other names for them.MUCH has been written about their golden silk – more about that later.

The Golden silk orb weaver (Trichonephilaclavipes) was formerly known asNephila clavipes. Nephilameans “fond of spinning” andclavipesmeans “club-footed,” possibly a reference by Linnaeus to the dark tufts of hair on six of the female’s legs.Recently, it and a dozen other genus members were moved to the genusTrichonephila– the Golden orb weavers.Historically, GSOWs were the only member of that genus in North America, but in 2014, an East Asian species called the Joro spider found its way to Georgia, and it’s been spreading out through the Southeast .

Look for GSOWs in open areas in woods or edges, preferably near wetlands or coastal areas. 

Male GSOWs spin trap webs until they reach maturity, but then they set off to find a mate.When they find a female’s web, they quietly move onto its periphery and feed on some of the prey she catches, and a female’s web may host a number of males.Dewdrop spiders Dewdrop Spider – Field Station and Spiney-backed orb weavers Spinybacked Orbweaver– A Spider for Snowbirds – Field Station also live on the web’s outskirts and share in the bounty.An amorous male will approach the female while she is distracted by a meal, and he signals by vibrating both the web and his abdomen (he’s cautious, but there’s not a lot of sexual cannibalism in this species).Males don’t produce much sperm, and they replace it slowly, so they favor newly-molted females who have not mated yet.After he mates/attempts to mate, a male may move on to a new web.

Females place two or more egg sacs, each containing a few hundred eggs, on surfaces near their web .Hatching may be triggered by environmental cues in their damp habitats. The spiderlings stick together for about a week after hatching , and then they disperse.By late summer, the tiny spiderlings of spring have reached full size and are making conspicuous webs.

This is a big spider that builds a big, strong web (up to six feet in diameter) that is capable of snagging some big prey, like moths, fast-flying horse flies, dragonflies (which are both GSOW eaters and eat-ees), butterflies , beetles (this one is June-beetle-size) , cicadas, and grasshoppers.Though they trap both small and large prey, they prefer to eat the bigger insects.

The webs are sturdy enough to capture birds. Daniel M. Brooks, in an article titled “Birds Caught in Spider Webs: A Synthesis of Patterns” published in the Wilson Journal of Ornithology (2012), wrote that a review of international literature and list servers found 69 accounts of birds trapped in webs.Nephilaspecies, especially GSOWs, accounted for half of the reports of mostly hummingbird-sized birds (though a small dove was reported, and the author personally observed a Swainson’s thrush tangled in a web), and while some were able to free themselves, a significant number had been killed and wrapped by the spider.

The asymmetrical, orb-type web is usually located between two and eight feet off the ground (but may be at treetop height). When prey is abundant, GSOWs may cache as many as 15 wrapped insects in a “barrier web” – a debris-strewn area along one side that serves to warn/block predators and help keep the web clean.One source said that the organic waste held in the barrier web may attract insect prey by its odor.

GSOWs’ main predators are wasps that collect them to provision their egg chambers, and birds. 

Unlike many species of orb weavers that replace their webs daily, eating the old web to harvest its protein, GSOWs repair damaged webs.Researchers believe that the yellow tint, the intensity of which the spiders can control, may attract bees, and it may also help to camouflage a web in the shade.A number of females may make webs close to each other .

This is some serious silk!!!Nephila/Trichonephilasilk has a high thermal conductivity, is stronger, by weight, than steel (it’s being studied with hopes of replicating its extreme strength), and it has some interesting medical applications.Wikipedia reports that it may be beneficial in surgeries involving the nervous system because it may guide and encourage neuronal regeneration.

Wikipedia also reports that hunters in New Guinea make fishing nets from the silk.

Finally, enterprising folks have experimented with it as a textile, creating garments (thanks to the labors of millions of spiders) .

FUN FACT ABOUT SPIDERS: the tips of the legs of spiders that wander around and don’t make trap webs point outwards, and the tips of the legs of trap-web-spinners point inwards.

FUN FACT ABOUT NEPHILA/TRICHONEPHILA SPIDERS: The genus Nephila is not only the oldest-known surviving spider genus (165 million years), but it includes the largest-known fossil spider.

The BugLady

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Tumbling Flower Beetle /field-station/bug-of-the-week/tumbling-flower-beetle/ Wed, 25 Feb 2026 14:57:28 +0000 /field-station/?p=16934 Howdy, BugFans, Way back in 2010, when the BugLady wrote an episode called “Big Beetle – Tiny Beetle,” the tiny beetle was a generic Tumbling flower beetle. There are a whole bunch of (unrelated) beetles that share the common name “flower …

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Howdy, BugFans,

Way back in 2010, when the BugLady wrote an episode called “Big Beetle – Tiny Beetle,” the tiny beetle was a generic Tumbling flower beetle. There are a whole bunch of (unrelated) beetles that share the common name “flower beetle” – hermit, bumble, shining, soft-winged, and more, along with the long-horned flower beetles. Tumbling flower beetles are interesting little critters, so here’s an enhanced biography – new words, new pictures.

The psychological principle called “The Law of Closure” explains that when we see text with partial or misspelled words, our brains tend to serve up the missing information, often without our even noticing its absence (which is why over-familiarity with a text makes for bad proof-reading). The incomplete becomes complete. That being said, the BugLady must confess that whenever she sees the name of the Tumbling flower beetle family – Mordellidae – her brain always fills in the name of a kind of lunch meat, Mortadella. BugFans may come to their own conclusions/diagnoses about that. 

Tumbling flower beetles, so-called because of their method of locomotion, are also called Pintail beetles, because of their pointy anatomy. There are more than 2,000 species of Tumbling flower beetles distributed over six continents, with 200-plus species in North America, and 68 of those in Wisconsin. They seem to be in continuous taxonomic limbo – there’s been a lot of shuffling and more is expected to happen. They can be a very confusing bunch – to tell the difference between some of the species, you have to count the ridges on the hind tibia and tarsus (leg and foot). All of the species in North America belong in the same subfamily (Mordellinae), and speaking of names, there are some very fine genus names like Mordellistena (the largest genus), Hoshihananomia, and Yakuhananomia.

These small (about ¼”), active, caraway-seed-shaped beetles always remind the BugLady of a flea on a flower. Tumbling flower beetles are wedge-shaped (tapered toward their pointy rears), and are covered with short hairs that are silky and slippery and that may give them an iridescent shine. They have long, flattened, hind legs (the better to tumble with, my dear) and hump-backed bodies, with heads angled down almost under the first segment of the thorax (sort of a “pre-somersault” position). Their elytra (wing covers) are shorter than their abdomen. 

Tumbling flower beetles are generally dark, but some are more decorative

Black tumbling flower beetle perched on a white yarrow flower head with yellow centers

In an article in the journal PSYCHE (1987) Deyrup and Eisner write that “The Mordellidae are small, wedge-shaped beetles commonly found in one of the most dangerous of all insect habitats, the open inflorescences of plants.”Food and habitat-wise, Tumbling flower beetles tend to be generalists. Adults feed on nectar and pollen (their hairy bodies make them effective pollinators), and some nibble on the flowers a bit.

The larvae, concealed within plant stems , leaves, galls, dead trees, or shelf fungi,feed on dead wood, the pith of herbaceous plants, and woody fungi, and larvae of a few species may be predaceous.Most sources agreed that although they like sunflowers, the larvae aren’t considered an agricultural pest.Downy Woodpeckers find the larvae in plant stems, and crab spiders capture adults on flower heads.

Five black tumbling flower beetles gathered on the center of a bright yellow composite flower

Do they tumble? Oh my, yes! When alarmed, which seems to be often, they bail, letting go of the flower and tumbling or jumping off. Part way down, they may spread their wings and fly (they are good flyers) or they may fall all the way to the ground, where they are impossible to find. They jump by pushing off into a spiraling somersault using one of their extra-long back legs, and they rotate clockwise or counterclockwise in the air, depending on which leg they pushed off on. Sources say that these gymnastics help the beetle position itself for flight. 

Deyrup and Eisner again: “Their chief protection against the many predators that frequent flowers is a series of convulsive leaps followed by rapid flight, as acknowledged in their common name, “the tumbling flower beetles.” Their escape from a predator’s grasp is facilitated by their wedge shape and covering of smooth, backward-pointing hairs, while their movement and purchase among stamens and floral hairs may be assisted by rows of tibial and tarsal setae strongly reminiscent of the combs of fleas. These escape mechanisms, while undoubtedly effective against many predators (including entomologists), have the disadvantage that they involve abandonment of the feeding site.

Three dark tumbling flower beetles feeding on the yellow center of a pink wild rose blossom

Adults emerge in late spring, romance ensues, and females lay eggs in decaying wood or in living plant tissue (there may be as many as 40 larvae in a single sunflower). Tumbling flower beetles often find themselves in the company of other Tumbling flower beetles and are said to be aggressive toward them. They overwinter as larvae in their food plant, and there’s only one generation per year. 

An article about Tumbling flower beetles on the Beyond Pesticides website states that “the tumbling flower beetle’s ancestors were some of the earliest insects to utilize flowers for food and habitat. In doing so, these ancient pollinators began an important collaboration between flowers and beetles which continues today.”

The BugLady

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Bugs in the News XVI /field-station/bug-of-the-week/bugs-in-the-news-xvi/ Wed, 18 Feb 2026 15:22:36 +0000 /field-station/?p=16911 Greetings, BugFans, Let’s take some time off from the relentless, 24-hour news cycle and enjoy a few bug stories.  MOSQUITOES – The BugLady always snickers at the obligatory TV news spot in mid-spring in which someone earnestly tries to predict …

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Greetings, BugFans,

Let’s take some time off from the relentless, 24-hour news cycle and enjoy a few bug stories. 

MOSQUITOES – The BugLady always snickers at the obligatory TV news spot in mid-spring in which someone earnestly tries to predict what kind of mosquito season is on the horizon (“Well, Pete, if we get a lot of rain, we could have a lot of mosquitoes this year…”). Whatever the summer brings, how do mosquitoes find you, and do they find you delectable? .

(The BugLady also snickers at the weather folks who report that visibility is limited to only five miles or two miles instead of ten. Most people don’t live where they can actually see five miles, and most of us aren’t flying an airplane. All we need is enough visibility – maybe a quarter mile in each direction – to be able to pull through an intersection safely. But that’s a different soapbox).

INSECT SPECIES – There are about 100,000 species of insects in the US, and almost one-fifth of those species can be found in Wisconsin! Most live out their whole lives without producing a single blip on our collective radars, and formal insect surveys are a recent phenomenon, so it’s hard to say what the population trends are for many species. .

spider web

SPIDERS: – Spiders would appreciate a little peace and quiet .

lady gaga treehopper

LADY GAGA TREEHOPPER – Ever wonder how newly described insects get their names

walking stick bug on the leaf branch

WALKING STICK – Our Northern walking sticks max out at about 3” long (counting their antennae, maybe 5”) (and what cute nymphs they have ). They’re dwarfed by this newly-discovered Australian stick insect .

bumble bee

BUMBLE BEES – Turns out that extreme heat can have an unexpected impact on bumble bees .

EXTRAFLORAL NECTARIES – Some insects protect the plants they live on, and the plants reward them for it . BOTW explored EFNs a while back Ants in My Plants Rerun – Field Station.

INVASIVE SPECIES ALERT – be on the lookout for a new alien species, the Elm zigzag sawfly – .  Here’s some info from the Wisconsin DNR .

The BugLady saw a fly sitting on the outside of her cottage the other morning. 

The BugLady

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Eastern Amberwing Redux /field-station/bug-of-the-week/eastern-amberwing-redux/ Wed, 11 Feb 2026 14:51:03 +0000 /field-station/?p=16898 Salutations, BugFans, 2026– When the BugLady wrote this episode in February of 2013, she kicked it off by griping about the weather – a favorite, February, indoor sport.This year, we’ve had many days of below average, below freezing, and below …

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Salutations, BugFans,

2026– When the BugLady wrote this episode in February of 2013, she kicked it off by griping about the weather – a favorite, February, indoor sport.This year, we’ve had many days of below average, below freezing, and below zero temperatures.How cold is it?Three weeks ago, one of her water pipes froze and burst, and when she tossed the sodden beach towels out the door into the yard, they froze instantly.They’re still stuck solidly to the ground.

This rerun contains a few new words (because who can look at a 13-year-old manuscript and not tweak it?), but all new pictures, because the Eastern Amberwing is a wondrous creature to photograph, even when it’s hovering just out of range.

2013– The weatherman keeps saying “Mixed precipitation” and it’s making the BugLady plenty crabby, so she’s going to think about dragonflies, instead. Here’s a little bit of sunshine on the wing.

Several BugFans have asked the BugLady how she selects the stars of BOTW.First, she needs a decent picture to spin the tale around, and Eastern Amberwings have posed prettily (some of them). This tiny dragonfly has some interesting stories to tell.

Close-up of golden Eastern Amberwing wings

At a hair under an inch in length, the Eastern Amberwing (Perithemistenera) is the second smallest dragonfly in Wisconsin (the very-uncommon Elfin Skimmer is a bit smaller and is not yellow).Some damselflies, like this Spreadwing , are longer than Amberwings, but damselflies are slim and dragonflies are bulky.Their flashy wings make them look bigger than an inch to the BugLady.The male EA’s wings are pure gold; the female’s wings are brown-spotted on a sometimes-amber background (she resembles a tiny Halloween Pennant, of previous BOTW fame).Males and females have yellowish legs and have rings around the segments of their abdomens.The abdomens of both are thick (the female’s looks especially swollen).

Because of their coloring, their rapid, erratic flight, and the way they twitch their wings and abdomens when at rest, EAs are considered wasp mimics.Their wasp “disguise” may save them from aerial and terrestrial predators, but the BugLady found a website instructing fly fishermen on how to tie an EA fly, so apparently fish are willing to take a chance.

Where do you find them?Over most of the US, east of the Great Plains and south into Mexico.Here in God’s Country, they fly in mid-summer, but they grace the landscape year-round in the southernmost parts of their range.Look for them near quiet orveryslowly-moving waters (the BugLady often sees them in the bays and inlets along the shore of the Milwaukee River).Look for them, too, far from water, hunting at grass-top-height over weedy fields or perched on vegetation at a woodland’s edge.

Where do you find them, entomologically speaking?In the order Odonata (the dragonflies and damselflies) and in the family Libellulidae (the Skimmers).Perithemisapparently is a reference to Themis, a figure in Greek mythology, and a number of other Skimmer genera incorporate Themis’s name.According to Berger and Hanson inDragonflies,tenerais Latin for “tender,” “delicate,” or “soft” and implies youth (a dragonfly is called ateneralduring the first few days of adult life).

They are “perchers,” and unlike most dragonflies, may be seen sitting on flowers (they arenotconsidered pollinators, despite the picture caption in one photo site).On hot, summer days, they may lower their wings to shade their thorax and point their abdomens skyward to reduce direct contact by the sun’s rays. Eastern Amberwings find food by patrolling or by perching and watching; they catch insects in flight, but they generally perch to eat them.Females often raise their abdomens while in flight.

Male Eastern Amberwing perched on a green leaf

The aquatic young (naiads) eat tiny fellow-aquatic invertebrates, and unlike the more specialized naiads of other dragonflies, they use all parts of their habitat, hunting at any depth in their pond’s water column.For their carnivorous ways, Eastern Amberwings and other dragonflies are given a thumbs-up by a Florida pest control service, which says, “From the tinyEastern Amberwing, to the flamboyantHalloween Pennant, dragonflies are some of the most important and charismatic beneficial bugs. They’re indiscriminate predators of many pest insects, including mosquitoes, flies, ants and wasps…… Next time you see one zip across your yard, consider saying thanks to the dragonfly for helping to control the pest population.”

Eastern Amberwings sure know how to court a gal.A male flies low over the water, patrolling a territory of choice egg-laying turf (weedy aquatic sites) about 20 feet wide and defending it vigorously – darting out at intruders and displaying with those spectacular wings.When a female approaches, he follows and courts her, swaying back and forth, abdomen raised. If she’s agreeable, she follows him home.He hovers over his territory while she evaluates it, and if she likes it, she gets him along with it.After mating, she lays eggs – usually alone, but sometimes under his watchful eye. The blob that she releases from the tip of her abdomen explodes as it enters the water, releasing as many as 150 eggs over the water’s surface.In his zeal to protect his “investment,” the male sometimes grabs an intruding male and flies in tandem with him, keeping him away from the female.

It’s not surprising that a critter that’s as flashy, as unmistakable, as widely distributed, and that has so many interesting behaviors has attracted the scientific community.A number of different studies have demonstrated, at least, that Eastern Amberwings have attitude. Here are some of the things that have been discovered about them:

  • Site fidelity– Once a male finds what he thinks is a high-quality spot to lay eggs (an oviposition site), he protects it by day (he leaves at night to roost in a tree).He will defend it for days, especially if he has mated there.If he deliberately changes territories, he “moves up” to a higher quality site.He can be evicted from his territory by a feistier male.
  • Heterospecific pursuit– Besides chasing each other, male Eastern Amberwings chase after any flying insect that could be mistaken for another Eastern Amberwing (that’s heterospecific pursuit). They’ve been observed pursuing large horse flies and small skipper butterflies, but they ignore larger dragonflies. Researchers concluded that following a horsefly was simply a case of mistaken identity of a similar-sized insect, but there may be something about the skipper’s coloration that pushed the Eastern Amberwings’ buttons.
  • The cost of doing business– Defending a territory is “expensive,” and the more “close neighbors” an Eastern Amberwing has, the costlier it is for him.Having more neighbors results in more intrusions.More intrusions mean more energy spent chasing intruders or simply darting around being territorial.Expensive? Yes, but non-territorial males rarely get to pass on their genetic material.
  • Home field advantage– Unlike those of some other Skimmers, Eastern Amberwing’s territorial disputes may escalate, but they are non-contact sports.If the aggression does not build, the territory-holder tends to win, but if the conflict escalates, victory often goes to the younger Eastern Amberwing.Males who had fewer interactions overall tended to have more energy and win low-key conflicts. The territory-holder may win other face-offs because he psyches out the competition or because the intruder decides he doesn’t like the territory enough to fight for it.
  • Spatial learning– Dragonflies can remember the locations within their habitat where they find food, breed, and roost, and they know the routes between those places.A male will be more faithful to a territory where he has mated and less interested in a territory where he’s been beaten by a rival.

The BugLady

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