A Tale of Two Butterflies

glaucopsyche_xerces

Pinned specimens of the Xerces Blue in the Field Museum of Natural History. Photo by Brianwray26, licensed under Creative Commons via Wikipedia.

There are no graceful ways to mention extinct species in casual conversation. Years ago, on a visit to San Francisco, a local friend asked what I thought of Golden Gate Park. “You’re a naturalist, right—isn’t that just your thing?” I made the mistake of answering honestly. “It’s very pretty,” I agreed, “but there are too many eucalyptus trees and I think it would be better if the Xerces Blue were still around.” Awkward silence followed. Our conversation had taken a sudden nosedive, just like the population of Xerces Blue.

The Xerces Blue (Glaucopsyche xerces) was a small, delicate butterfly belonging to a group poetically dubbed the gossamerwings. Tiny flecks of iridescent sky on the wind, they bumbled low over the sand dunes along the Pacific coast in search of their host plants, weedy, insignificant-looking vetches, or wild peas. Aside from a few naturalists at the nearby California Academy of Science, nobody paid much attention to them. Life went on.

As the developing city of San Francisco swelled and grew, enterprising settlers changed the environment to suit themselves. They filled in the marshlands on the eastern edge of the peninsula, planted windbreaks of eucalyptus and Monterey pines to stabilize the dunes for Golden Gate Park, and paved over everything in between. The population of the Xerces Blue flickered like a soap bubble, and abruptly vanished. The last one was spotted in 1943. The very traits that allow the Xerces Blue to flourish as a species—their isolated population, their dependence on specific plant species—meant their populations could not recover from any damages. Once they were gone, they were just… well, gone.

Unlike most extinct insects, which vanish unnoticed and unmourned by humans, the Xerces Blue enjoys a moderate degree of fame and notoriety in its afterlife. Officially, it was the first insect species documented to become extinct from habitat loss and urban development. And it became the namesake for the Xerces Society, a conservation non-profit dedicated to preventing any further insect extinctions from happening. But unlike the passenger pigeon or the dodo, there are no plaques, no statues, no monuments, and its name is barely mentioned in popular literature. All that remains are occasional references in books, a handful of specimens in sealed cases in natural history museums and perhaps a few flickers of memory from those lucky enough to see one alive. On my visit to Golden Gate Park, I grieved the loss of the Xerces Blue. The possibility of ever seeing one alive was gone now, and it felt unbearably tragic.

Even as I found myself enjoying the city of San Francisco and all it had to offer (including Golden Gate Park, despite myself), I could not help but question—was it really always a choice between urban development and natural history? Was the destruction of the Xerces Blue inevitable? What could we do differently in the future?

Another species of native butterfly offers new insights into my questions. The California pipevine swallowtail (Battus philenor hirsuta) is a smaller, bulkier subspecies of the more widely distributed pipevine swallowtail, found only in California. The caterpillars in their later instars memorably resemble black and orange alien slugs, waving poisonous tentacles as a deterrence to predators; the pupae bear an uncanny resemblance to Metapods from Pokemon Go. The caterpillars only feed on the endemic California pipevine (Aristolachia californica), and their populations were crashing along with that of their food plant. It seemed like the usual extinction narrative was up and running. I braced myself for the worst.

But the story abruptly changed directions. Tim Wong, a biologist working in Golden Gate Park, started growing California pipevine and raising swallowtails in his backyard. The population of swallowtails in the city swelled rapidly. The more pipevine he and others planted in the area, the more butterflies there were. The California pipevine swallowtail is still threatened—there are no real ends in this kind of work—but at least this was a step in the right direction. There is hope. Not too far from the last home of the Xerces Blue, another threatened butterfly species is rebounding. For me, haunted by dreams of vanished butterflies, it felt like a kind of absolution. Maybe this time we wouldn’t screw up.

I think it’s safe to say that no one loved the Xerces Blue the way Tim Wong loves the California pipevine swallowtail—not, at least, until it was too late. Certainly, the simpler biology and wider range of the swallowtail made it easier for its populations to recover. But having human champions, people who were too crazy and too dedicated to sit back and do nothing, turned the tide in San Francisco. And what exactly brought the butterflies back? Creating habitat. Propagating their host plant, California pipevine, planting it in gardens and raising caterpillars. Nothing too big or dramatic. Just small changes, expanded over a wider scale. Anyone could do it, and someone did. And everything changed as a result.

Actions like these remind me that my dreams of gardens full of life and hope are not pipe dreams—or pipevine dreams, for that matter. They offer us an alternative to the usual doom-and-gloom framework, the long, slow, slide or the short, abrupt route to to extinction. They depend not on helplessness, but on personal involvement, personal responsibility, personal action—a reminder that all our actions matter. If everyone cared about just one species or place the way Tim Wong cared about the California pipevine swallowtail—enough to go out of their way to help them flourish in their own community, literally their own backyard—the world would be a vastly different place. Certainly more diverse, anyway. And if just a few people cared—well, that, too, would make a difference between life and death, endings and beginnings, at least for the time being.

Looking back to our awkward conversation in San Francisco, I now know what I would say to my friend, and to everyone else who cares to listen:

“Somewhere, not too far away, there is something so precious you cannot bear to lose it. Find it. Help it. Plant the seeds in your garden; make space for it in your heart. All is not yet lost. All is not yet gone the way of the Xerces Blue. Those that remain, like the California pipevine swallowtail, can still come back to us. All they need is the opportunity. Let us help them come home.”

Learning to Love the Corn Earworm

Hale-Corn Earworm16-08-26

I fall in love the way some people drink coffee—quickly, all at once and at the slightest opportunity. This time, the object of my affection was a tiny tan moth, fluttering among a haze of purple tick-trefoil flowers in a power-line clearing in early evening. Every now and then it would alight on a blossom and feed before hovering away again, its wings fuzzy blurs of motion as it zigzagged through the field. I stalked it with a camera for several minutes, never removing my gaze from my quarry. It posed obligingly for me on a nearby stalk of tick-trefoil, its wings fully spread. As I held my breath and snapped the picture, I couldn’t help but notice its piercing green eyes. I was beyond infatuated—I was hooked. What was I looking at?

Zen master Fayan claimed that not knowing is most intimate, but the Greek philosopher Aristotle countered that all humans by nature desire to know. In this case, Aristotle won out. I posted the picture to an online community of naturalists and awaited their verdict, but I was unprepared for the truth. This beautiful moth and I had met before, under strained circumstances, and I hadn’t been so impressed with the results. The delicate creature that had captured my attention was actually the Corn Earworm (Helicoverpa zea) in an entirely different guise.

You’ve probably met the Corn Earworm, too, even if you didn’t know it at the time. It’s the caterpillar lurking at the tip of your newly-purchased summer sweet corn, fresh off the roadside stands, the proverbial serpent in paradise spoiling any illusions of perfection. Just like us, the Corn Earmworm loves those tender, developing kernels, and leaves a nasty trail of brown feces behind as it works its way down the cob.

Though unpalatable in their feeding habits, I’ve always found a few Corn Earworms a small price to pay for the sure knowledge that the corn in question wasn’t treated with synthetic pesticides. I don’t like them much, but I tolerate their presence, and I work to find ways to avoid them when possible. When I grow corn myself, I look for varieties that are naturally less susceptible to damage—like the heirloom ‘Strawberry Two Inch’ popcorn—and I’ve never had any problems with the earworms. (The European Corn Borer larvae, on the other hand, were not so easy to write off.)

More annoyingly, I find the Corn Earworm wriggling at the center of my best and juiciest tomatoes. There are all sorts of things that go wrong with tomatoes—early blight, late blight, cutworms, hornworms, blossom end rot—but the Corn Earworm is particularly vexing because you are so close to finally getting that ripe tomato in your mouth… until you notice the hole on the side conveniently hidden by foliage and the trail of frass smeared across the outside. Lovely.

Unlike most caterpillars, which tend to eat only one or two kinds of plants, and only those plants, the Corn Earworm is not a picky eater. Its common name shifts to reflect wherever you find it—the Cotton Bollworm, Tomato Fruitworm, Sorghum Headworm, and Soybean Vetchworm are just a few of its many incarnations— but by no means is it limited to those particular plants. In all of its larval incarnations, it feeds with gusto on developing fruits—and its fellow caterpillars, if it can get them—before dropping down to the ground to pupate in the soil.

After a rapacious juvenile delinquency, the adults settle down to relatively harmless existence nectaring on flowers. They are also, as I discovered, staggeringly beautiful in their own quiet way. But a female can lay thousands of eggs in her brief lifetime and perpetuate the cycle of destruction throughout the growing season. They don’t intend to vex me; it’s just an inevitable side effect of continuing their lineage. Once I knew them as adults, I could still squish the larvae when I found them, but I no longer mourned quite so much about the ones that got away.

Learning to love the Corn Earworm might seem like a challenge, but this story ends better than most of my love affairs these days. Unlike most species I fall for, it is abundantly common and ubiquitous wherever agriculture is practiced. Its populations are continually increasing despite vast quantities of pesticides sprayed to control them. Its larval form is an obnoxious pest in my plantings, but they are not going away any time soon. Now that I know what to look for, I find the adult Corn Earworm Moth nectaring on the garlic chive flowers in the evening, just outside my doorstep. The adult Corn Earworm Moth comes to sit with me on an urban patio four stories off the ground, where few other flying things dare to tread. In the age of the Anthropocene, the Corn Earworm will be with us always. It’s just as well that I’ve found a reason to love them.

What’s In a Name When It Comes to Moths?

toothed somberwing

National Moth Week has come and gone, but it’s still a great time to get outside and look for moths. Why bother with moths, you ask? Well, they come in a dizzying variety of colors, shapes and sizes, and occupy just about every terrestrial habitat in North America. They have fascinating life cycles and strategies for survival, lurking literally behind every leaf and branch. Many of them come to electric lights at night, so you can sit back, relax, and wait for them to come to you (a plus for fieldwork). But there’s another reason to study moths, something that rarely gets mentioned in the literature – their amazing names.

Where else on a summer night can you encounter the Cynical Quaker, the Unarmed Wainscot, Drexel’s Datana. the Georgian Prominent or the Toothed Somberwing (photo of this last moth above)? Aren’t you intrigued by the existence of the Confused Haploa, the Girlfriend Underwing, the Honest Pero, and the Friendly Probole? What’s the story behind the Shattered Hydriomena, the Retarded Dagger, or The Laughter? How can you sleep at night when the Black-Blotched Schizura might be resting on your porch? What about the Goat Sallow, the Abrupt Brother or the Grateful Midget?

There are moths with more prosaic names, of course. The Reed Canary Grass Borer, for instance, leaves precious little to the imagination. Others, like the Spiny Oakworm Moth or the Yellow-Necked Caterpillar Moth, are named for their juvenile appearance, and bear little resemblance to their former selves. Many species are named for the plant their caterpillars feed on, or some youthful quirk of habit, like the Pecanleaf Casebearer and the Basswood Leafroller. Other species go by multiple aliases, depending on their age: Woollybear Caterpillars grow up to be Isabella Tiger Moths, and Hickory Horn Devils mature into the elegant and reformed Regal Moths.

Other names invite questions. Is the Dubious Tiger Moth any less trustworthy than its fellows? What happened to the Once-Married Underwing? Why is it not the Divorced Underwing instead? (That’s different, of course, from the Widow Underwing, which is an entirely different species.) Is the Nameless Pinion actually nameless? What is the Grieving Woodling’s problem, and is the Disparaged Arches moth really that bad?

Clearly, lepidopterists have a lot fun (and more than a few beers) when it comes to moth names. It’s time for the rest of us to catch up on the action. Fortunately, it’s never been easier to learn about moths. Flick on a light switch in the evening and see who shows up. Take pictures with a camera or smartphone and post them online to websites like BugGuide or iNaturalist for identification suggestions and tips. You’ll be amazed by how much is out there once you start looking.

If you live anywhere between Maine, Minnesota, Iowa and Virginia, you can flip through the excellent Peterson Field Guide to Moths of Northeastern North America by David Beadle and Seabrooke Leckie, which has color photographs of 1,500 of the most charismatic species you’re likely to encounter. Unlike old-school entomology displays, where dead moths are pinned with their wings spread, the Peterson Guide features live moths in their characteristic poses, just as you see them in the field. The endpapers have silhouettes of the family groups, so with a little practice, you’ll be distinguishing your Tiger Moths from your Tussock Moths and your Prominents from your Geometers, just like the pros. Similar volumes for the rest of the continent are expected to follow.

Sure, most people are excited when a charismatic megamoth like a Luna Moth shows up in their lives. The bright colors of the Showy Emerald or the Pandorus Sphinx will make even the most jaded naturalist’s night. But I’m always happy to see a Dusky Groundling or the Cloaked Pug, however drab and grey their markings. The Beggar and The Neighbor (not to mention the The Slowpoke) will always have a place in my heart. Even a Simple Wave is a cause for celebration. My field notes sound like I’m auditioning for comedy night at the local club – and that’s before The Bad-Wing shows up. And I can promise you this: as a student of moth names, I will never, ever be bored.

For the Love of Bees

Hive of Activity. Photo credit: Gabe Andrews

Oh How She Glows

In Yellow, She Glows. Photo credit: Gabe Andrews

We want cheap groceries, strawberries in March, and impeccable lawns. We strive for dominion over the web of life, especially our domesticated crops and the pests that threaten them. Bees get caught in the middle of it all. Habitat homogenization and the increased use of pesticides –particularly neonicotinoids – have contributed to the decline of our pollinators, and bees have been hit the hardest. There are practical implications for this loss. We could talk about the $15 billion that honeybees contribute to the U.S. crop economy, or about the food on our fork (of which 1 in 3 bites requires insect pollination) [1]. Undoubtedly, California’s profitable almond industry – a crop entirely reliant on honeybee pollination – would crumble overnight with the complete loss of honeybees. But with the disappearance of these proficient pollinators we risk much more than a painful sting to our economy; we jeopardize our humanity.

Bees offer us creative inspiration. The hive and its workers give us metaphors persistent in everyday language. The brilliant construction of hexagonal honeycomb encourages architectural marvels that promote efficient design (circles, pentagons and octagons leave wasted space; triangles and squares –with their greater relative circumference –lack the storage capacity of hexagons) [3]. The cooperative society inside a hive emboldens us to become better humans. The careful collection of nectar reminds us to slow down and taste the sweetness of a good day. As worker bees gradually transform nectar to honey, they teach us fortitude and patience. Though these lessons are in shorter supply with a decline in apian educators, our individual and collective actions can keep them from disappearing altogether.

Humble Bumble

The Humble Bumble. Photo credit: Gabe Andrews

Many already stand –smoker in hand – ready to save the bees. Hobby beekeeping has gathered momentum, pollinator-friendly gardens are on the rise, and even the federal government has perked its ears. Organic agriculture has grown by 250% since 2002, a sign that consumer decisions have driven the market away from pesticide reliance [4]. All of this comes as welcome news to honeybees, but their step-sisters haven’t received nearly the hype. With all the attention placed on domesticated bees, wild bees continue their downward spiral. In the Northeast alone, close to 25% of bumblebee species (Bombus spp.) have disappeared or declined throughout their range [5]. Hopefully we can target our efforts more broadly to protect all genera of bees.

We know that habitat loss severely influences pollinator decline; our porches and backyards cover once-wild ground, but let’s keep our vision on the present for a minute. Landscaping with native plants is a great way to attract and support your local bees (not to mention reduce your mowing commitment). When the time comes for pruning, the hollow twigs of some goldenrods (Solidago spp.) and coneflowers (Echinacea spp.) make great homes for orchard (Osmia spp.) and small carpenter (Ceratina spp.) bees. Wooden boxes filled with holes serve a similar purpose for larger bees.  Don’t forget to leave pockets of bare soil for ground-nesting bees (Colletes spp.). Minimizing pesticide use could help keep bees from dying, but habitat and food will give bees a chance to live.

Watching and keeping bees is more art than science. With this mindful craft comes patience, awareness, and imagination, but you don’t need a honeybee hive to enjoy such an experience. Yes, bees are essential to the health of our economy, our planet, and the diversity of our dinner plate. A world without almonds and apples would be a shame. But to live without the unwavering brilliance of such humble insects would be a tragedy.

Gabe Andrews is a first-year graduate student in the Field Naturalist Program at UVM. 

[1] Hopwood, J. et al. (2012). Are neonicotinoids killing bees? A review of research into the effects of neonicotinoid insecticides on bees, with recommendations for actionThe Xerces Society for Invertebrate Conservation.

[2] Williams, G.R. et al., 2015. Neonicotinoid pesticides severely affect honey bee queens. Scientific Reports, 5, p.14621. Available at: http://dx.doi.org/10.1038/srep14621.

[3] Mathis, C.R. and Tarpy, D.R. (2007). 70 Million years of building thermal envelope experience: building science lessons from the honey bee. Available at: https://www.cals.ncsu.edu

[4] USDA Office of Communications bulletin April 15, 2015

[5] Vermont Center for Ecostudies: Bumble Bees

 

A [Local] Monster Mash

Here in Vermont you can hardly go outside without seeing signs about buying local.  Local foods are labeled in grocery stores, restaurants proudly display maps of Vermont with pins pointing out where they source their ingredients, and everybody who’s anybody seems to have a CSA share. But for some reason every year around this time even the most devout locavores import their Halloween monsters from far away.  Mummies more at home in Egypt smile out at you from windows, tarantulas usually found in tropical regions crawl all the way into candy bowls in Vermont, and vampires hop planes from Transylvania to lurk on residential porches for a few weeks every October.  Enough!  I say it’s time to put an end to the madness of imported creepies and crawlies, and to get to know a few of our own.  And so, I present to you a Halloween line-up of locally and sustainably sourced (and not-so-scary) monsters:

The Stigmata Mummy-Wasp (Aleiodes stigmator)

Mummified Acronicta Caterpillar with exit-holes of Stigmata Mummy-Wasp, photo by Bryan Pfeiffer

Mummified Acronicta Caterpillar with exit-holes of Stigmata Mummy-Wasp (Photo by Bryan Pfeiffer)

Here’s the good news: the stigmata mummy-wasp didn’t make the monster list for having a painful sting. In fact, these wasps are small and don’t have stingers.  In place of a stinger on their hind end, these wasps sport an ovipositor, which they use to inject their eggs under the skin of an innocent and unsuspecting host caterpillar.  After the eggs hatch the wasp larvae chew a hole in the underside of the caterpillar, causing it to leak fluids that dry and essentially glue the caterpillar to a plant.  Next the larvae mummify the caterpillar by eating the soft innards and lining the empty body with silk.  Inside the hollow caterpillar husk the wasp larvae spin their own cocoons and pupate into adults.  When they emerge from their cocoons they chew their way out, leaving behind the dry husk of a caterpillar that looks like it has been sprayed with buckshot.

Even though this may sound straight out of science fiction, stigmata mummy-wasps are native to Vermont where they generally inhabit wetlands and floodplains.  Though the wasps themselves are small and hard to find, the mummified caterpillars are not.  Their riddled mummies can be found clinging to sticks year round, and if you find one in late fall you might want to watch it closely – you might be lucky enough to spot one of these little monsters emerging.

The Oleander Aphid (Aphis nerii)

Oleander Aphids on a stalk of Swamp Milkweed

Oleander Aphids on a stalk of Swamp Milkweed

There are many types of aphids, but while I was researching for this list one variety stood out: Oleander aphids.  These little orange and black bugs grab onto a stalk of milkweed (or any of several other plant hosts) with specialized sucking mouthparts and drink it dry.  Their story only gets weirder from there.  Oleander aphids develop from unfertilized embryos and all adults are female; males do not occur in nature.  Adult females can be winged or wingless, the former usually showing up when the host plant is overcrowded or dying so that they can fly off to infest a new host.  Both the winged and wingless adults excrete live nymphs instead of eggs, and a colony can grow quickly.  The nymphs develop through five different phases before becoming adults, but nearly all phases look the same and vary only in size.

If an army of jack-o-lantern colored female clones sucking the life out of a plant isn’t Halloween enough for you, I should also point out that oleander aphids have their own mummifying parasitoid wasp.  The aphidiid wasp (Lysiphlebus testaceipes) lays a single egg inside an aphid nymph or adult.  When the egg hatches the wasp larva consumes the aphid from the inside, so that it develops into a brown papery husk of its former self.  Much like stigmata mummy-wasp larvae, the wasp larva then spins a cocoon inside this mummified aphid, pupates, and chews its way out, leaving behind a bloated brown aphid mummy with a hole in it.  When a dense colony of oleander aphids is heavily parasitized, half or more of the aphids in the colony may eventually be only mummified remains while their sisters slurp placidly beside them.  How bewitching.

Horsehair Worms (Paragordius varius)

Resembling an animated, wiry strand of hair, horsehair worms are often spotted writhing in the bottom of woodland streams and pools. As charming as that may sound, their mating behavior is less than romantic.   When a female indicates a willingness to mate, the male releases a cloud of sperm in her general vicinity, and then swiftly dies.  The sperm forms a glob, which finds its way to the appropriate receptacle on the female within the next 24 hours.  A fertilized female goes on  to lay as many as 6 million eggs, and then she too perishes.  As It turns out this is the least offensive part of their life cycle.

Horsehair Worm (on top of leaf) found in a stream in Bristol, VT

The eggs mature, and in 2-3 weeks millions of tiny worm larvae are hunting for hosts in the pool or brook.  They infect many different kinds of aquatic phase insects, including mosquito larvae, and when the infected larva matures into its adult phase, the worm larva comes along for the ride.  Eventually this intermediate host insect is consumed by the host the worm is really looking for: crickets and their relatives.  Once inside this final host the worm begins to absorb nutrients through its skin from the host’s body.  Having no mouth or digestive system of its own, the worm requires an environment where food comes pre-digested.

While growing inside its host, a process that takes 2-3 months, the worm is also practicing mind-control.  An infected cricket will not chirp at all as chirping uses up precious energy and can attract unwanted attention to the worm’s comfortable home. Once the horsehair worm has fully developed inside of its cricket host (reaching lengths of four inches or more), it releases a chemical that drives the host to seek out water.  Meanwhile the worm has carved a hole in its host’s side, and shortly after the host hits the water the worm will emerge in its free swimming adult phase to mate, leaving its injured but still living host behind to begin the cycle again.

From the mummified remains of caterpillars, to the mind games of a parasitic worm, our Vermont backyards boast a roster of Halloween monsters rivaling those of the silver screen.  So this Halloween, when you find yourself telling scary stories with friends, borrow a tale right from your own backyard…and sustainably source your monsters.

Shelby Perry is a second year student in the Field Naturalist Program.  She would like to acknowledge Field Naturalist Graduate, Charley Eiseman, for his help fact-checking sections of this post, and his wonderful book Tracks and Sign of Insects and other Invertebrates: A Guide to North American Species.  

Monarchs Head South Toward an Uncertain Future

MonarchMontage-BryanPfeifferIf I went outside right now, hopped in the car, and started driving, it would take me 45 hours to reach the Monarch Butterfly Biosphere Reserve in Michoacán, Mexico, some 2,823 miles away. Though I badly want to see the groves of sacred firs (Abies religiosa) quivering and dripping with orange and black wings, I’m not leaving today. For now, I am content to have witnessed one of this year’s migrants emerge from its chrysalis.

When I first saw the chrysalis I thought the tiny, metallic gold markings seemed suspiciously intricate for a mere caterpillar’s changing room, and peered at them as if they might instead be explained by sci-fi alien manufacture. Apparently, these spots allow oxygen to reach the developing structures and organs of the enclosed butterfly.

The next morning, in the span of about 15 minutes, this female butterfly inched downward out of her chrysalis, re-distributed fluids from her distended abdomen to unfurling wings, and washed her face in preparation for what was to come. Her autumn journey to the Transvolcanic Mountains of central Mexico— if she can complete it—will take two months. To put this voyage in perspective, it is around seven times the distance traveled by caribou as they migrate from summer habitat to winter haunts. Caribou are billed as the land mammal with the longest migration in North America, whereas the Monarch is a butterfly whose flight has been described as “slow and sailing.”

monarch-1280x920The spring migration of Monarchs to New England is carried out by five different generations, each pushing north at distances more commensurate with their two-to-four-week lifespan and the floating nature of their flight. Monarchs hatched in late summer are among the generation that will live for several months to travel an incredible distance by putting their reproductive tendencies on pause, or rather, on diapause.

Diapause for the Monarch is a sort of flying hibernation that allows the butterfly to extend its lifetime, endure migration, and make it through the winter. Unlike hibernation, however, only specific environmental conditions can induce an organism to enter or exit diapause. In the case of a Monarch, when the days are long enough and the temperatures are just right, the overwintering butterfly shakes herself reproductively awake, mates, and then travels a few hundred miles north to lay her eggs on milkweed before dying.

Sadly, the odds for our particular young Monarch and her progeny are dismal. She faces habitat loss, changing environmental cues, invasive species and car windshields along the many miles of her journey. The population of Monarchs east of the Rockies is estimated to have declined by 90% since its level in 1995.

Nevertheless, government agencies, non-profit organizations, and concerned citizens are mobilizing to try to prevent the migratory Monarch’s extirpation. As with many environmental issues, large-scale actions such as policy change will be crucial. However, because the plight of the Monarch also plays out in our backyards, opportunities to help are close to home. You can plant native milkweeds to benefit individual butterflies. You can join other citizen scientists in supplying data to strengthen and inform the measures we take to protect Monarchs; check out monarchwatch.org.

The first, beautiful moments of a young female Monarch reawakened my awe and concern for this species. Instead of being crushed by the terrible thought that, if Monarchs were to go extinct, this mystical experience might become a mythical one, I am spurred to share the urgency of the situation. Urgency is more powerful when it is underpinned by wonder. And though this combination might seem like a fragile set of wings with which to entrust the fate of a species, I take comfort in the thought of Monarchs fluttering south towards Mexico, unfazed.

Anya Tyson is a first-year Field Naturalist student

Beyond the Jeep Road Sits Coyote — Wilderness in 2015

Southwestern desert

Southwestern desert

By Levi Old

On the first day of a 90-day expedition, our team made camp at the end of a jeep road. The afternoon sun, low in the sky, blanketed the desert’s red and orange rocks. Daylight quickly shifted into dusk. The rocks faded into shapes, and dropped shadows on slick rock in the crescent moonlight. The wind-worn surfaces that stood so vibrant in daytime were gone.

After dinner and a meeting about the next day’s plan, we embraced the opportunity to sleep out in the open. I found a flat boulder, climbed into my sleeping bag, and looked up at the night sky. The 10 students wandered around searching for sleeping spots, chatting with nervous anticipation and preparing their new equipment for a night’s rest.

“I bet this never gets old,” said Ben, 20, from Wyoming.

“Seriously,” agreed Lily from New York, “I’ve never seen stars like this before.”

I peeked over the lip of my sleeping bag and noticed the students gazing at the night sky.

The two college students traveled far from their comfortable existences to attend a three-month wilderness leadership course in the heart of the southwestern desert. Along with my colleague, I was their instructor. Around us, there was a more distinguished instructor— wilderness. Continue reading

Zombie Aspen Leaves

populusleaves-550x410By Bryan Pfeiffer

Rotting and fallen to earth, they might appear dead. But they are not quite dead. They are the undead: zombie aspen leaves.

Find them as you walk the brown autumn paths – yellow leaves with a patch of green tissue radiating from the base of the midrib. Here in Vermont, these are mostly quaking aspen (Populus tremuloides), but I also find the green on big-toothed aspen (P. grandidentata) and, rarely, eastern cottonwood (P. deltoides).

When a friend and I first encountered these some years ago, I collected a few and queried a handful of smart botanists for answers. Many had theories; none had an explanation. It wasn’t until I put a leaf under a dissecting microscope that I found the explanation to be less zombie than something from the film “Alien.” The beast lies within.

populus-caterpillar-moth-550Residing in a tiny pocket of tissue near the base of the green patch is a translucent caterpillar not much more than 2 millimeters in length. It’s feeding in there; I could see the frass (caterpillar poop). With help from Dave Wagner, the renowned entomologist at the University of Connecticut, our critter turns out to be a moth in the family Nepticulidae, probably Ectoedemia argyropeza or most certainly a member of that genus.

“The really cool thing is that the larva secretes an anti-senescent substance that keeps part of the leaf alive – probably a cytokinin,” Dave wrote in an email. Cytokinins are plant hormones that promote cell division. In this case, it seems, the caterpillar keeps part of a leaf alive so that it can keep eating.

This moth is also parthenogenetic; females can produce fertile eggs without help from males, which, as it turns out, are quite rare.

For now, however, the caterpillar will continue to dine in the verdant patch of an otherwise dead leaf. It will pupate for winter. And the tiny adult will emerge to fly in spring. Many species in this genus are black and white with orange scales around the head. But don’t expect to find one. Your best bet for discovering this animal is to watch the trail for patterns in poplar leaves this fall.

And if you’re raking them up, please note that some of those leaves, well, they could be saying, “I’m not dead.”

The Nuclear Option for Dragonflies

By Bryan Pfeiffer

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A Common Green Darner (Anax junius) / © Bryan Pfeiffer

On a crisp, sunny day in September, after what was probably a typical summer for a dragonfly (which involves flying around, killing things and having sex beside a pond), a Common Green Darner took off and began to migrate south. As it cruised past the summit of Vermonts Mt. Philo, with Lake Champlain below and the Adirondacks off in the distance, the dragonfly crossed paths with a Merlin.

The Merlin, a falcon that kills in flight, swerved, plucked the dragonfly from the sky with its talons and began to eat on the wing. As the falcon and its prey continued southbound, all that remained in their wake was a single detached dragonfly wing, falling like an autumn leaf toward fields at the base of Mt. Philo.

Eagles, hawks, falcons and Monarch butterflies aren’t the only migrants moving south past mountains this fall. Joining them are dragonflies. Although biologists know plenty about the fall raptor and Monarch migrations, we are only beginning to discover, with some creative chemistry, where these dragonflies go and how migration figures in their conservation.

Fly or Die

Most dragonfly species do not migrate. In fact, most are now dead, having already mated during the summer season, leaving behind eggs or larvae to survive the winter. The killing frost will finish off much of what’s still on the wing. But some survivors will leave.

Wandering Glider (Pantala flavescens) / © Bryan Pfeiffer

Wandering Glider (Pantala flavescens) / © Bryan Pfeiffer

Among the 460 or so dragonfly and damselfly species native to North America, at least five are classic migrants: Common Green Darner (Anax junius), Black Saddlebags (Tramea lacerata), Wandering Glider (Pantala flavescens), Spot-winged Glider (Pantala hymenaea) and Variegated Meadowhawk (Sympetrum corruptum). Each species is on the move this fall.

Dragonflies migrate for the same reasons other animals migrate: to avoid inhospitable conditions, in this case habitats that freeze or become too cold for the dragonflies themselves or their insect prey. Monarchs go to Mexico. Broad-winged Hawks leave for wintering grounds stretching from southern Mexico into South America. Dragonflies head south to who knows where.

Having studied birds for two centuries, biologists know well their breeding and wintering distributions , even to the point of learning the destination of a particular warbler or sparrow after it leaves us in the fall. Ornithologists catch lots of songbirds in nets and place around one leg a tiny silver bracelet embossed with a unique number – an avian social security number – and then release the birds to the winds. A small percentage of them, still sporting their bracelets, are later recaptured while in migration or on wintering grounds thousands of miles away. Better yet, we’re putting small electronic transmitters on large birds, such as Bar-tailed Godwits and American Woodcocks, and tracking their movements real-time with satellites.

On of my tagged Monarchs before heading off toward Mexico.

A tagged Monarchs before heading off toward Mexico.

We can even track the movement of a single butterfly. I myself have placed little stickers, each bearing a unique alpha-numerical code, on the hind wings of more than 1,000 Monarchs here in Vermont and elsewhere in North America, and then set each one free to fly toward Mexico, where many are later encountered by conservationists searching for the buttterflies once they arrive in Mexico. With each recovery, we learn more about Monarchs and how they migrate.

The “Heavy” Hydrogen

Dragonflies aren’t so obliging. For one thing, we’re clueless about where they go. Monarchs concentrate each winter in stands of Oyamel Fir in mountains west of Mexico City. So we know where to find them and how to protect them. Tagging or somehow marking a dragonfly would be like putting a message in a bottle and tossing it out to sea. Actually, I suspect we’d find the bottle before the dragonfly.

Yet it turns out that we need not tag or otherwise mark these migratory dragonflies because they themselves carry clues about where they have been. If the Merlin doesn’t get it first, we can catch any migrating dragonfly, analyze trace elements in its tissue and determine roughly how far it has flown.

Our marker is water, more to the point the two hydrogen atoms in water. Recall from high school chemistry that hydrogen nucleus normally contains a single proton and no neutron. But a tiny fraction of hydrogen atoms around the world carry one proton and one neutron. We call it “heavy hydrogen,” or deuterium. And unlike other such atomic variations among elements (which can be radioactive), deuterium is stable in the environment – a “stable isotope”– and stable in the wing of a dragonfly.

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Credit: Migratory Dragonfly Partnership

The amount of deuterium in water varies somewhat predictably in North America. You can map it. The ratio of deuterium to hydrogen in water falling as rain or snow changes on a gradient corresponding roughly with latitude. Water in Alberta, for example, carries a different deuterium-to-hydrogen ratio than water in Alabama.

Because dragonflies grow up as nymphs in water, they incorporate the local deuterium ratio into their tissue. It’s like a dialect or an accent that a dragonfly bears for life – whether as a nymph in water or a free-flying adult in migration. A Common Green Darner on the wing over Mt. Philo or Miami unwittingly carries a particular deuterium ratio, a birth certificate that tells us generally where it grew up. You are what you eat – or drink.

This science isn’t perfect. We can’t pinpoint a dragonfly’s natal waters in the way we know where a banded bird hatched or a tagged Monarch emerged. But stable isotopes are helping us track the range of migrating dragonflies. It’s “better living through chemistry.” After all, we can’t really know a bird or butterfly or a dragonfly – and what it might need in the way of conservation – until we know all the places it lives or wanders.

By the way, you need not be a chemist to help track dragonfly migration. We’re counting dragonflies in the same way we count migrating raptors during hawkwatches each fall. Learn how to do it and report what you find with help from the Migratory Dragonfly Partnership.

And while we’re out there counting, if a Merlin happens to catch a dragonfly first, we can still make a difference … by catching one of those dragonfly wings floating toward Earth.

Bryan Pfeiffer is a writer and field naturalist who specializes in birds and insects. He teaches writing in the University of Vermont’s Field Naturalist and Ecological Planning Programs.

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