The BugLady checked the (highly searchable) website of the Wisconsin Odonata Survey (Wisconsin Odonata Survey<\/a>) to see if anyone had reported a Common Green Darner yet.\u00a0They are early migrants from the southeastern part of the country, traveling north with the warm weather, and they\u2019re often the first dragonfly species of the year.\u00a0Here\u2019s an episode about them from nine years ago.\u00a0New pictures, a few new words.\u00a0<\/p>\n\n\n\n 2017<\/strong><\/p>\n\n\n\n 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 \u201cWinter Lite,\u201d 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\u2019s much more to the Common Green Darner story.<\/p>\n\n\n\n They are in the darner family Aeshnidae, a group of large, powerful dragonflies (\u201cdarner\u201d because their long, darning needle-like abdomen has led to folk tales about their sewing people\u2019s lips or ears shut). <\/p>\n\n\n\n Most of our Wisconsin darners are in the famously-confusing mosaic darner genus\u00a0Aeshna<\/em>.\u00a0Common Green Darners (Anax junia<\/em>) (\u201cLord of June\u201d) are one of two species of\u00a0Anax<\/em>\u00a0darners found in the state.\u00a0Common Green Darners\u00a0<\/a>are, well, very common, not just here but across the country.\u00a0And Central America. And Hawai\u2019i.\u00a0And Canada. And there are populations in Tahiti and the West Indies.\u00a0And strong winds have blown individuals to Great Britain, China, and Russia.\u00a0The other\u00a0Anax<\/em>, the stunning Comet Darner (Anax longipes<\/em>) is a rare visitor and even rarer breeder in Wisconsin Comet Darner – Anax longipes – BugGuide.Net<\/a>. \u00a0<\/p>\n\n\n\n Common Green Darners are big, with a 3\u201d long body and a 3 \u00bd\u201d wingspan, and their striking \u201cwrap-around\u201d compound eyes may be made up of as many as 50,000 simple eyes apiece.\u00a0Their wings often show a golden tinge in flight. They practice sexual dimorphism \u2013 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.\u00a0Tenerals (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.\u00a0Both males and females have prominent cerci (claspers) at the abdomen\u2019s tip.\u00a0Common Green Darners have a characteristic bull\u2019s-eye spot on their \u201cforehead\u201d that Comet Darners lack. They can move each wing independently, which lets them hover, and even fly backwards.\u00a0They perch vertically, frequently in low vegetation, so they usually spot the BugLady long before she spots them.\u00a0<\/p>\n\n\n\n The long, slim, immature green darners (naiads) are found in still or\u00a0very<\/em>\u00a0slowly-moving, shallow waters, preferably without sunfish and bass (nice set of naiad pictures here Dragonfly larva, Green Darner – Anax junius – BugGuide.Net<\/a>).\u00a0Adults frequent the air above those habitats but may be seen far from water.\u00a0<\/p>\n\n\n\n Two populations of common green darners \u2013 one migratory, the other resident – form tag teams in the air over Wisconsin.\u00a0Migrants 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\u2019s offspring, of the darners that flew south in the fall (no, they apparently do not return to their natal ponds). \u201cShivering\u201d their wing muscles to heat up the thorax allows them to be active in cool weather, and they also bask in the sun.\u00a0 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).\u00a0The 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.\u00a0<\/p>\n\n\n\n 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.\u00a0These residents live a month or two as adults, depositing their eggs in late summer as the migrant adults emerge.\u00a0Resident naiads overwinter under the ice in a state of suspended animation called\u00a0diapause<\/em>\u00a0and take 10 or 11 months to mature (possibly more, in the chilly waters \u201cUp North\u201d), while the migrant naiads need less than half that time in the warm waters of summer.\u00a0<\/p>\n\n\n\n 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.\u00a0Females oviposit in the open, in woody and herbaceous plant material below the water\u2019s surface, with the male typically retaining his grip on her head.\u00a0<\/p>\n\n\n\n The books say that these are the only darners that oviposit in tandem.\u00a0The books also say that a couple flying in tandem may be strafed by rival males.\u00a0The attendant male doesn\u2019t have many options; he may flap his wings at the intruder, shake his abdomen, land in vegetation, and even bite his challenger.\u00a0According to Paulson, in\u00a0Dragonflies and Damselflies of the East, females may curl their abdomen under and close their wings when under attack.\u00a0The 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).\u00a0<\/p>\n\n\n\n The BugLady once found a female stuck in an especially dense and sticky, dragonfly-eating patch of blanket algae.\u00a0Did the female attempt to perch on the algae as she oviposited and get her wings stuck, only to be abandoned by her mate?\u00a0Or, alternatively, did she get thirsty and then get stuck?\u00a0Dragonflies \u201cdrink\u201d by immersing their abdomen – water enters through the exoskeleton (the BugLady was able to fish her out with a stick).\u00a0<\/p>\n\n\n\n The naiads are active predators that will eat anything they can grab using their foldable \u201clower lip\u201d (labium<\/em>) – zooplankton, other aquatic insects (including dragonfly naiads), tadpoles, larval salamanders, and fish fry are all fair game.\u00a0In his wonderful write-up of the Common Green Darner, Kurt Mead (Dragonflies of the North Woods) muses that \u201cIf 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<\/em>\u201d (read the whole account at Dragonfly Behavior | MDS<\/a>) (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\u2019s even an \u201caquatic\u201d parasitic wasp that lays its eggs in those of the green darner –\u00a0Aprostocetus polynemae<\/em><\/a>\u00a0apparently walks down a twig or leaf stem into the water to find dragonfly eggs.\u00a0<\/p>\n\n\n\n Adults catch insects in the air and may eat them in mid-flight or on a perch.\u00a0They can also pick prey from a leaf or from the ground, and they\u2019ve been known to stake out bee hives, to the distress of the bee-keeper.\u00a0At least one ambitious Common Green Darner killed a hummingbird, and this fact is mentioned in every darner write-up, though the BugLady suspects it\u2019s 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.\u00a0<\/p>\n\n\n\n So, Common Green Darners migrate. Like birds, they respond to a suitable weather front \u2013 cold fronts for the southern flight and warm fronts for the far less conspicuous northern trip.\u00a0The 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.\u00a0Late summer\/fall migration is dramatic, huge swarms may take hours or days to pass a fixed point.\u00a0Bluffs on the west edge of Lake Michigan are great places to catch the show at eye level.\u00a0<\/p>\n\n\n\n The Common Green Darner is the State Insect of Washington \u2013 so much more exciting than Wisconsin\u2019s honeybee (and you thought the state insect was the mosquito!).\u00a0\u00a0<\/p>\n\n\n\n As always, don\u2019t eat them \u2013 they carry parasites.\u00a0<\/p>\n\n\n\n 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 \u201cje ne sais quoi<\/em>\u201d as \u201cjean es se qua<\/em>.\u201d\u00a0She had consulted Monsieur Google about the correct spelling, and she had, alas, believed him.\u00a0<\/p>\n\n\n\n The BugLady <\/em><\/p>\n","protected":false},"excerpt":{"rendered":" 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.\u00a0They are early migrants from the southeastern part of the country, traveling …<\/p>\n","protected":false},"author":38860,"featured_media":16985,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":"","uwm_wg_additional_authors":[]},"categories":[8],"tags":[1003,804,11,551],"class_list":["post-16984","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-bug-of-the-week","tag-anax-junius","tag-common-green-darners","tag-dragonflies","tag-green-darner"],"yoast_head":"\n![\"Male](\"https:\/\/uwm.edu\/field-station\/wp-content\/uploads\/sites\/380\/2026\/03\/darner-cg17-5-300x300.webp\")
<\/figure>\n\n\n\n![\"Female](\"https:\/\/uwm.edu\/field-station\/wp-content\/uploads\/sites\/380\/2026\/03\/darner-grn-fem08-5aarz-300x215.webp\")
<\/figure>\n\n\n\n![\"Close-up](\"https:\/\/uwm.edu\/field-station\/wp-content\/uploads\/sites\/380\/2026\/03\/darner-cg21-9rz-300x215.webp\")
<\/figure>\n\n\n\n![\"Common](\"https:\/\/uwm.edu\/field-station\/wp-content\/uploads\/sites\/380\/2026\/03\/exuvia-darner19-6rz-300x300.webp\")
<\/figure>\n\n\n\n![\"Pair](\"https:\/\/uwm.edu\/field-station\/wp-content\/uploads\/sites\/380\/2026\/03\/darner-cg21-4rz-300x215.webp\")
<\/figure>\n\n\n\n![\"Common](\"https:\/\/uwm.edu\/field-station\/wp-content\/uploads\/sites\/380\/2026\/03\/darner-CG-stuck15-3rz-300x215.webp\")
<\/figure>\n\n\n\n![\"Common](\"https:\/\/uwm.edu\/field-station\/wp-content\/uploads\/sites\/380\/2026\/03\/darner-cg-oof22-10rz-300x300.webp\")
<\/figure>\n\n\n\n