Vinerunt, futuerunt, ierunt

Very rough translation: They loved us, then left us. (the cicadas, that is.)¹ 

¹ Guest blogger’s subtext — Maybe if I dazzle the readers with a title in the colorful language of Pompeiian graffiti, they’ll forgive me for not posting pictures as beautiful as Ted’s. Well, anyway…

On this year’s US Independence Day, we in the St. Louis area were able to proclaim our freedom from the 5-week-long din of cicadas, or so the TV “news” reporters would have us believe. For me, it was more of a return to the dominance of human-made noise; the faint drone of a distant highway, the monotone roar of a neighbor’s lawn mower, the repetitively plosive engine of one of the many diesel pickups that float by, with the CD player’s bass thumping at an almost certainly hearing-damaging decibel level.

Magicicada burrows

I started my celebration early in the day, by doing some gardening and rearranging in the yard. Moving a pile of concrete paving stones, I reached the bottom one and lifted it, and was greeted with a view of abandoned nymphal emergence burrows made by just a few of the many thousands of periodical cicadas that graced my yard with their presence this year. The burrows were already showing wear at the edges in their disuse. A little later later in the morning, I heard the whoooooooa-ooh of a last, lone Magicicada tredecim male from the hackberry tree—first one call, then another, then no more. But nature’s course proceeds, and as afternoon drifted into evening, I was pleased to hear the first of the dogday, or annual, cicadas of the genus Tibicen. These are not truly annual; They emerge every year, but actually take several years—4 or 5, it is said—to develop from egg to adult. 

The four Magicicada species that can be found in the St. Louis area, near the western edge of Periodical Cicada Brood XIX (a.k.a. the Great Southern Brood), are famous for their intermittent emergence as adults, every 13 years. (Life spans of 17 years occur in three, more northern species that do not occur in the St. Louis area). In fact, during years to either side of the two emergences of Brood XIX that I’ve experienced since moving to this area 24 years ago, I have always heard, and if really lucky, seen a few, one or two years before and after the “scheduled” emergence. But, the vast majority stick to the plan of feeding on the xylem sap of tree roots as subterranean, tan-colored nymphs for 13 seasons before coming out of the ground, then molting to the ever-so-buggy-looking, winged, black insects with red eyes and wing veins, that “freak everyone out” during their mass emergences. 

The mass emergence is all about reproduction, the successful transmission of genes to the next generation—you know, Darwinian fitness. When a female happens to “like” the song of a particular male, she flies to him, then is courted a for a bit with a different song, before “succumbing to his charms”. Mating typically takes place up in trees. But, being amoral creatures of little brain or scruples, they may choose indelicately to copulate on a porch rail or other such public place. 

Magicicada mating

Magicicada sipping Gentiana andrewsii

Consumed with sex, the adults don’t eat much, but occasionally one sees a cicada poking its proboscis into some soft plant tissue for a drink of sap (clearly exhibiting the relationship of these large insects to those smaller sap-feeders, the aphids and such). A little sap-drinking does little damage to plants, but the insertion of eggs by the mated females into small twigs of woody plants can do quite a bit of “natural pruning”. This would be more of a concern if it happened every year, I suppose, but it really also does little damage in the long run, especially on a mature tree. Still, I would have appreciated it they hadn’t found my recently planted black gum tree such an attractive oviposition site. 

Magicicada damage on Acer saccharum

Magicicada meets Nyssa sapling

But I don’t begrudge them this. I miss their mass serenade. I treasure the remembered sight of a corpulent hairy woodpecker muddying itself to pull one nymph after another from rain saturated ground. I delighted in seeing a surprisingly chubby chipmunk perched fearlessly on an exposed root as it munched a cicada whose wings never properly expanded. Perhaps best of all was watching a red-shouldered hawk clumsily hop about on the lawn to snarf up cicadas that weakly fluttered to the ground. But now, the periodical cicadas are, till May of 2024, mere shells of their former selves. 

To end on a pretty note, here’s a gaudy cicada that was attracted to lights of the scientific station’s laboratory building in Yasuní National Park, Ecuador, and obligingly posed for a photo on the windowsill.

Ecuadorian cicada

Copyright © James Trager 2011

Promiscuous Plants

Naturalists have long been aware of the greater tendency for plants than for animals to create viable interspecies hybrids. This is attributable not only (as some might expect) to a higher likelihood of passive plants whose mating is mediated by pollen-hungry insects, or the wind, to hybridize more often, but rather to a greater ability of plants, with the simpler design of their anatomies, successfully to build a functioning organism with a Gemisch of genes from parents of different species. Such hybrids occur naturally, and are often reported in regional floras. Further, the advent of modern techniques for characterizing DNA has revealed that hybridizations of yore have given rise to numerous species, and higher lineages, in plants, in fungi, and to a lesser extent in animals.

My recent wanderings in quest of fall flora photos at Shaw Nature Reserve really brought this phenomenon of admixture of species to mind as I was examining populations of the three Gentiana species that live at the reserve. All three are fairly recent introductions at SNR, added to the flora in several locations in our prairie and wetland habitat reconstruction program. Hybridization among these gentian populations was first brought home in my observation over the last three years of increasing numbers of purplish and bluish and outright blue individuals in a population that was originally pure white gentian – Gentiana alba. This population was sowed in the mid-1990s as part of a mesic prairie reconstruction in the watershed of our wetland complex.

Gentiana alba, G. andrewsii and their lavender tinted hybrid growing side by side at Shaw Nature Reserve.

Pale or white bottle gentian, in "pure" form.

A few years later, 50 or so meters distant, separated by a dense row of trees and shrubs, and in a much wetter habitat in which water pools after every rain and seeps subsurficially much of the year, blue bottle gentian – G. andrewsii — was sowed into a wet prairie / sedge meadow reconstruction.

The rich blue flowers of the blue bottle gentian, Gentiana andrewsii

At first the two populations grew independently and remained separate, but what I surmise was a combination of water borne seed transport (along the shore of a pond whose edge both populations are near), and bumblebee borne pollen transport, conspired to bring gametes of the two species together, creating what population geneticists call a hybrid swarm, and what taxonomists call a — well, I can’t write it in polite company such as my readers.

Observe in the sequence of images above how a bumblebee gyne (a potential queen of one of next year’s annual bumblebee colonies) pries open a bottle gentian flower and dives in for a long drink of nectar at the base of the large vessel. Apparently the nectar is copious, because bumblebees may remain in a single gentian flower for up to a minute.

The result of pollen transport among pale and blue bottle gentians, a hybrid of intermediate characteristics.

While there are other populations of both species on the reserve (one hopes, out of bumblebee range from each other) that may retain their genetic integrity, the rampantness of the admixture at this site does give me pause.

And it gets worse! — On drier ground up the slope, among a dense planting dominated by prairie dropseed and little bluestem grasses,  a third gentian known as downy or prairie gentian – Gentiana puberulenta – was established from a seed mix sowed 10 years ago to convert the watershed of the reserve’s wetlands to prairie vegetation.

Unlike the two previously mentioned species and their hybrids, the downy gentian's petals open wide at anthesis, admitting entry to small bees and even to spindly-legged potential pollinators such as syrphid flies.

And now those perverse bumblebees have gone and defied the laws of speciesness and created what appear to be hybrids of this third gentian species with the other two. Honestly, I don’t know whether to feel that I have done some sort of wrong by creating the situation that allowed this to happen … or simply to be intrigued by this unforeseen outcome of my work, and to wonder what will come of it after I’m gone?

The gentian in the upper photo appears to be the offspring of a cross between white and downy gentian parents, while the one in the lower photo appears to be the result of a cross between blue bottle and downy gentian.

The joys of ecological restoration

Indian paintbrush and lousewort now dominate patches of SNR

I moved to Missouri in the summer of 1988, having experienced 8 years of generous support of my family’s livelihood by my research on the infamous imported fire ants of the US Southeast, and their relatives in South America. When I arrived in the Midwest, I  hoped to land a job as an insect taxonomist in a university or museum, a goal of mine since before entering college. But this dream was one that even before moving to Missouri was dimming, and then receded ever further from the realm of possibility for me (and for traditionally trained taxonomists, generally), once here. So, I began to re-think what I might do with my work life. It would be something, I hoped, that would make some use of all the course work (mostly in entomology and botany) and research (on ant systematics) I had done during my 24 years (!) of getting educated and four additional years as a post-doc. As or more important, whatever job I ended up in would somehow have to allow me to share my life-long love of nature with others.

A museum drawer of ant specimens mounted for taxonomic study, the ants no doubt frustrated by the years of inattention they have received as I have tended to the duties of my day job.

Early in my residence in eastern Missouri, I made the acquaintance of the naturalist at a 2500-acre (1000-hectare) nature reserve outside of St. Louis. Shaw Arboretum, as it was then known, is country cousin to the world-renowned Missouri Botanical Garden, and is named after the Garden’s founder Henry Shaw. Long story short, in the summer of 1990 the naturalist mentioned to me that he would soon retire, the position would become available, and that I ought to apply. So I applied, and was hired as the arboretum’s naturalist in January 1991.

A dolomite glade plant endemic to a few counties in eastern Missouri, this leatherflower was established at SNR in the 1930s, but expanded exponentially after prescribed fire was introduced in the 1990s. Here, an ant characteristic of glades and dry prairies forages on the flower.

When I came on board, the “Arboretum” had mostly ceased to be an arboretum (a formal collection of trees for display, breeding and research), and most folks seemed unable to either pronounce or define the word. Indeed we learned, through a public survey, that the strange name and the stone wall in the front actually dissuaded people unfamiliar with it from entering! Yes, there were a few patches of exotic trees scattered around the property, especially in the conifer collection near the front entrance know as the “Pinetum”, but ever since the Garden had decided around 1930 that it would not, afterall move all of its horticultural operations to this then very rural site (the original intent of its purchase), formal arboretum and botanical garden type activities had been few and far between, and the site began gradually reverting from abandoned farmland to a wilder sort of place, as well as a haven for native biota. Thus, on its 75th anniversary in the year 2000, Shaw Arboretum was renamed Shaw Nature Reserve.

Colony-founding queen bumblebees are the primary actors in loosening pollen with ultrasound from shootingstar anthers, and distributing it about the plant population.

Around that time, my title changed too, to “Restoration Biologist”. The job is multifaceted; presenting public programs and classes on various aspects of the site’s natural history, writing and reviewing articles, acting as liaison to the vigorous regional group of academic ecologists who use the site for research and teaching, a very intermittent personal research program on ants resulting in sporadic publications, and last but certainly not least, ecological restoration.

Ecological restoration, in the broad sense, consists of  two primary practices:

  • Restoration of a natural community to structure and species composition presumed characteristic of an  ;;earlier condition (however arbitrary or ill-defined).
  • Reconstruction of regional, native-like habitats, de novo, using locally acquired native plant propagules in the appropriate settings of soil, hydrology,  slope aspect and climate.

Both  require essentially perpetual, follow-up maintenance, including invasive species control, mowing, haying, grazing, selective timber removal, species richness enhancements, and prescribed burning. All of these have many variations and nuances in application, and there can be impassioned arguments about their implementation in the literature, at conferences, and in forums and blogs on ecological restoration, native plants, butterflies, beetles, etc..

An ecologically conservative lily ally of undisturbed moist soil habitats now thrives in prairie plantings at the Reserve.

Attitudes about ecological restoration vary, among practitioners, among sociologists and philosophers, and in the general public. One broad attitudinal schism lies along the lines of  whether ecological restoration activities are some sort of primitivist, grand-scale gardening, or do they represent ecologically valid landscape conservation? Another question some pose is to what extent we should interfere with “natural successsion”? Be this as it may be, most people with functioning sensory perception agree the results can be very beautiful. The loveliness of the mosaic of colors in the herb layer of a spring woodland is inarguable, especially so after it has had its woody stem density reduced, and had the leaf litter burned off, to allow more light, rain and seeds to the soil surface — even where there is genuine concern about damage to invertebrate assemblages residing in forest duff. A waving meadow of grasses and flowers in a tallgrass prairie planting, intended to replace just a few of the tens of millions of acres of this ecosystem that have succumbed to the plow, has its own grand beauty, though its per-square-meter species density of plant species remains less than half that of a native prairie remnant and it is dominated mainly by habitat-generalist insect species rather than prairie specialists, even after 30 or more years.

A self-introduced grassland ant forages among a thriving, human-introduced population of this wet prairie gentian.

The smaller, daily rewards of restoration, to the practicing ecological restorationist and to those who visit his or her work, are many. Over 20 years, in the opened-up woods, restored glades and prairie and wetland plantings at SNR, I repeatedly have enjoyed the “sudden appearance” and increase in populations of ant species (of course) that I never observed during my early years of working at SNR (then scouring it for purposes of preparing an annotated ant list). The feeling I get upon discovering that a grouping of shooting star, royal catchfly, bunch flower or bottle gentian plants, are in bloom at a site where I spread their seeds five, seven, or even ten years earlier is a bit like that one feels when a child is born. The spontaneous colonization of SNR grassland plantings by prairie ragged orchid never fails to amaze me. Bird, or frog, or katydid and cricket songs in a former crop field or pasture, as the “restored” vegetation fills in and matures, is as pleasing to my ear as it is to my soul.

A few days ago (in early July), the director of the Reserve came to my office asking if I had noticed a purply pink, “possibly orchid” flower growing on a section of a berm (planted with native vegetation) in our 32-acre wetland complex. I had not been in the area recently, but headed right out to see what it was. Joyously, and not a little surprised, I learned that seeds of the purple fringeless orchid, sowed at a location nearby 17 years previously, had washed to this site, taken root, and as terrestrial orchids are wont to do, flowered after so many years!

The black-legged greater meadow katydid thrives in low areas and near bodies of water in SNR

The prairie ragged orchid began to appear in old fields and prairie plantings where prescribed burning occurs at SNR. It has not been seen in fields maintained exclusively by mowing or haying.

The purple fringeless orchid surprised the restorationist and St. Louis area botanists by flowering in the SNR wetland area 17 years after the original sowing.

Copyright © James Trager 2010

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The Inexorable March of Spring!

Granted, the progress of spring seems to advance in halting baby steps with occasional falls onto its muddy bottom, rather than as a determined forward march, but spring is welcome, no matter how it arrives. When little green tips start poking up and there’s a bit of that “spring smell” in the air, I simply must get out and catch up on the status of Nature — the old-fashioned way (she doesn’t have a Facebook account). Over the last week, I’ve gone forth in search of signs that everything else living is about as tired of winter as I am, and wants to get this spring show on the road! There is already so much happening, I can’t recount it all here — A partial list of unphotographed notables: owls breeding; hawks nesting; woodcocks doing their silly, repetitive and almost invisible (because it’s nearly dark) courtship displays; wood ducks on forest ponds; year-round resident songbirds reestablishing territories; spring peepers, chorus frogs, wood frogs and southern leopard frogs singing, especially in the fishless ponds; winter crane flies and midges swarming in sun flecks in the woods; wild filberts, silver and red maples flowering, etc…

Formica pallidefulva sniffs the spring air

Of course, I look for the first ants out at this time of year, though with the exception of 10 March, when the temperature exceeded 70F, they haven’t been notably active. However, that afternoon I encountered, among others, a worker of Formica pallidefulva poking its head out cautiously to sniff the spring air. This is one of my favorite local ants — largish (5-6mm), abundant, active in daylight even when it’s hot, usually shiny bronzy red to red-brown, usually with a darker gaster (the apparent abdomen of ants) around here, but ranging from a beautiful reddish gold (in the deep South) to almost pure black-coffee brown (New England and southern Canada) across its wide geographic occurrence (Rocky Mountain foothills of Wyoming to New Mexico, all the way east to Québec and Florida). It has the added charm of being the host species to a wide range of social-parasitic and dulotic (“slave-making”) ants both in its own and in another closely related genus, with which it lives in temporary or permanent mixed colonies (as with the Polyergus illustrated in my last post). The image below of these ants bringing home a charred earthworm was taken almost one year ago, as one of Shaw Nature Reserve’s prairie areas was beginning to resprout after a prescribed burn a few weeks earlier. Ants will take their food raw or cooked!

Formica pallidefulva with charred earthworm

Prenolepis imparis alate in the clutches of a gerrid

Another ant I mentioned last time I was with you, Prenolepis imparis, has the distinction of being the only ant in our fauna that has mating flights while there is still a good chance of frost in the forecast for the next few weeks. In this picture of a mating pair at  BugGuide, note the size difference that inspires their name “imparis”, Latin for disparate. Any time after mid-February when it is sunny and not too windy, and the temperature rises above 65F, the winged males and females reared the preceeding fall, fly out to partake of a grand insectan orgy. Typically, they have big flights on the first couple of appropriately warm days, then some smaller ones (i.e., fewer individuals participating) over the next few weeks. The flying males look like gnats, bobbing up and down in drifting swarms, a few feet off the ground over a shrub, near a woodland edge or in a sunny opening. (One of my co-workers got into the midst of a group of such swarms once when we were conducting a prescribed burn in a wooded area, and I recall her commenting she “felt like Pigpen with all the little bugs flying around”!) The much larger, golden-brown females lift slowly off the ground, fly ploddingly (or is it seductively?) through the male swarms, are there mobbed by the tiny fellows, and then glide away and slightly downward, mating in flight with the winner of the males’ tussling. Rather clumsy fliers, the females do not always land in a good spot, as occurred to this hapless one that ended up as a feast for a water strider. Those that survive break off their wings, dig a burrow, seal themselves in, and raise a small brood of workers on food produced in their own bodies (like say, milk in mammals or “cropmilk” in doves and some other birds.)

But lest you to think I only have eyes for ants, I feel indeed fortunate to have encountered a tarantula this week, of the same species as Ted recently posted and I didn’t even have to go to Oklahoma for it. This bedraggled individual was at the mouth of its completely flooded burrow in what is most often a very dry habitat — a dolomite glade. Stunned and muddy at the time, my guess is this creature, belonging to a resilient and ancient lineage, will dry off, clean up, and saunter away as soon as she warms up.

Aphonopelma hentzi in flooded burrow

And speaking of emerging from flooded burrows, how about this handsome fellow, a male three-toed box turtle, his sex revealed by his bright orange and red markings, coming up for a breather? In truth, it was perhaps only just warm enough to make him need air, but not really enough so for him to be up and about, so he just sat there, nearly immobile, looking pretty, notwithstanding mud and leaves glued onto his shell.

Male box turtle emerges

Copyright © James C. Trager 2010

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Ants invade Beetles in the Bush!

For months now, your Beetles in the Bush host, Ted, has been nudging me to blog, in the end resorting to offering me a guest blogger gig at BitB. Given this golden opportunity, I’ve decided to utilize my web-logging debut to introduce my favorite insects, the fabulous Formicidae. First, a disclaimer: I have not mastered ant photography, and so will rely on the undisputed king of ant photographers, Alex Wild, through links to his numerous, unexcelled images.

Since about age 5, I can remember being interested in virtually anything living, but especially in small, active creatures. From the beginning, I have had a particular attraction to ants. With some notable exceptions, and aside from the pulchritudinous feature of their svelte waists, ants aren’t what most folks would call pretty, but they are — How else to say it? — just plain “cool”!

First, who are they and where do they come from? Ants constitute a single family, Formicidae, within the insect order Hymenoptera, so their relatives are wasps, bees, sawflies, horntails, gall wasps, and a vast array of small parasitic wasps that are mostly unappreciated except by specialists who study them. Within Hymenoptera, the ants are considered to belong to the superfamily Vespoidea, along with hornets, paper wasps, potter wasps and other solitary relatives.  The evidence at present indicates the first animals we would call ant had diverged from their common ancestry with these other stinging wasps some time in the Cretaceous, 130 million years ago, more or less.  Ants are classified in a varying number of subfamilies, currently at about 20. Fossils in amber up to 100 million years old represent early members of several modern subfamilies, and a few extinct groups. Most of us in the Northern Hemisphere Temperate Zone are familiar only with the big two subfamilies, Formicinae (carpenter ants, weaver ants, honey ants, etc.) and Myrmicinae (fire ants, harvester ants, leaf-cutter ants, etc.). In much of North America, folks may also be familiar with an abundant member of another subfamily, Dolichoderinae, namely odorous house ants, which frequent our gardens, kitchen counters, wall spaces, and even electrical outlets, especially in spring.

Ants are a conspicuous and often dominant presence in the World of the Little (or, what Piotr Nascrecki, in one of my favorite books, calls the “Smaller Majority” ). It is difficult for any observant person to sit still, outdoors in good weather, and not begin to see ants doing what ants do. They scurry about singly, in pairs or threesomes or foursomes, or in long lines, or columns. Our notice may be further piqued by their habit of transporting sundry bits of biomass or mineromass (pebbles, etc.).  Often this is just taking out the inedible food waste, or sawdust or soil excavated while expanding or remodeling their nests.  Less visibly, because more diffusely in space, ants carry a variety of items from foraging to their nests to provide nutrition for their colonies, or to add mass or create functional structure to their nests (to create better drainage, to provide incubation space for developing brood, and in some desert ants, to capture dew). In one of the most spectacular examples of ants transporting things, the so-called “slave-making” ants carry home the mature brood of a related species, these young ants later maturing in the brood-robbers’ nest to become its work force!

Shiny red workers of Polyergus lucidus return with pupae pillaged from a nest of Formica incerta several meters away. Two brown and differently proportioned workers of the latter that matured from raids earlier in the life of this Polyergus colony may be seen at the right of the photo.

Perhaps, not so widely known is that most of what most ants carry home is not some large, heavy particle in their mandibles, but rather is liquid carried in an expansible section of their esophagus called the crop. Because of the fine diameter of their gullets, adult ants cannot eat anything other than the most minute solid particles (e.g., pollen grains, loose cells from their prey).  Solid items may be cut up to feed to the legless, pale larvae, or the larvae may even be placed directly upon the killed prey to bite into it and feed on their own, using their flexible “necks”.  Adult ants get pre-digested food in return, in the form of glandular secretions loosely termed saliva, but which may be either a glandular secretion from the larva itself or simplify pre-liquefied flesh of prey lapped up from the larva’s messy eating.  In some lineages, known as Dracula ants, adults actually “bleed” the larvae through rapidly healing wounds made at particular locations on the larval exoskeleton.

Okay, I need to get back to my regular work, so let’s bring this home (to winter in the United States). Many of us are now in the dead of winter, or so it would seem. But, on sunny days, sap is beginning to flow upward in maple and other trees, and one ant species may actually be seen, creeping slowly through the woods, in search of dead arthropods and earthworms, or perhaps some sweet sap oozing from a sapsucker wound in a tree. This is Prenolepis imparis, sometimes called “winter honeypot ant”. This is a partial misnomer. While foragers may indeed fill their crops to over-full with sweet sap or honeydew, the very bloated “honeypots” in the deep nests of this ant are in fact, fat pots, having converted their food to whitish body fat. This is later converted to a glandular secretion that serves as food for developing larvae.  These ants are likely to be seen anywhere near where oaks of just about any species grow, and the where the soil is moist but well-drained. Look for these shiny little dark brown ants during your walks in the woods, on the sunny days that are sure to increase in number and warmth in the coming months.

Copyright © James C. Trager 2010

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