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The Perfect Storm . . . A Decades-Long Barrage of Stressors

August 29, 2020 -

How many times recently have you heard someone declare how badly they want 2020 to be over? Unless you’re the human equivalent of Eeyore and a true glutton for punishment, this year has been one nightmare after another, and it has dampened the collective mood all around the globe. The narrative of this year has been nothing short of overwhelming: a once-in-a-century pandemic which has killed almost 200,000 Americans and close to 1 million worldwide; a near-collapse of the global economy; racial tensions escalating to levels unseen since the Civil Rights Movement; the ugliest politics of our lifetime; children having to be ‘educated’ by sitting in front of screens by themselves; massive unemployment; facemasks and social distancing; blatant lies being touted as factual news; rampant deforestation of the topics; callous immigration policies; enormous wildfires raging in several parts of the world; devastating unemployment; peaceful protests being turned into violent riots on urban streets; natural disasters which are rapidly increasing both in frequency and intensity . . . need I go on?  While death is an inevitable part of any lifecycle, the recent passing of some of our most beloved celebrity icons, like Kobe Bryant, John Lewis, Kirk Douglas, Little Richard, Olivia de Havilland, Kenny Rogers, Naya Rivera, Carl Reiner, and now Chadwick Bozeman, certainly hasn’t helped. Is it any wonder, as Michelle Obama has candidly admitted in recent weeks, that many of us are feeling heightened anxiety, depressed moods, and an unusual heaviness in our hearts?

Fortunately, many (certainly not all) of these somber circumstances are interrelated, so finding a ‘solution’ to one problem will, in turn, help alleviate another. The impending creation of a coronavirus vaccine will resolve several of them. Depending on which way things go, this November’s election could attenuate others. Thankfully, because we can see that many of the things that have gone so wrong in 2020 have finite lifespans, the hope of a brighter tomorrow is what keeps us looking forward. Resilience is in our DNA, as life on our planet depends upon adaptability and hardiness in the face of a wide array of environmental pressures. We will get through this year–and we’ll come out the other side stronger, wiser, and, hopefully, far more empathetic toward the plights of others. Looking back years from now, we will likely recognize what a turning point this was–ironically fitting, as that hindsight will indeed be 2020.

Sadly, the future does not look as bright for one of our most wondrous invertebrate cohabitants on this Earth, the Monarch Butterfly. This is the time of year when we typically begin noticing a dramatic increase in Monarchs in our gardens and meadows, as the Chesapeake Bay region is a late summer staging ground for the species, prior to their famously documented migration to Mexico in mid- to late-September. The Monarch is an outlier in the insect world, as humans award it a ‘celebrity’ status generally reserved for much more prodigious and charismatic creatures, like Polar Bears, Manatees, Pandas, Mountain Gorillas, and Cheetahs. What American child has not studied the Monarch life cycle in elementary school science class? Who has not gasped at photographs from the Mexican wintering grounds of Monarchs, where tree branches droop under the weight of far too many butterflies to count? Who among us has not popped open a milkweed pod and blown seeds to the wind, in hopes of inspiring future generations of Monarchs to lay eggs in that very spot? It’s safe to say that most of us know more about the Monarch than about any other insect; it certainly has a more reputable public image than any of the others! Most of them, quite frankly, just bug us.

That positive reputation is well deserved.  What an amazing evolutionary story Monarchs tell! One of the few migratory insects, the Monarch is a creature that weighs slightly less than a paper clip, with paper-thin wings that reach a span of four inches at most, yet is able to fly well over 75 miles per day during its migration. In all, many Monarchs complete a migratory route of 3000 miles over a 6- to 8-week period. They congregate by the millions in such small and remote mountainous areas that scientists were unaware of the exact location of their wintering sites until 1976. Lincoln Brower, who spent six decades studying Monarchs, declared the winter spectacle in Mexico to be “one of the great biological wonders of the world.” Perhaps most incredible is that when they set off on this journey, they’ve never made it before; only their ancestors have! Indeed, during the course of any given year, four or five generations of Monarchs have passed, with some generations devoting almost all of their energy to reproduction (and, hence, living a short life of only 2-6 weeks) but others putting their resources into migration and overwintering in the cool climes of the central Mexican mountains; with slower metabolism, these can live 6-8 months. It’s a fascinating and complicated adaptive strategy and, until recently, had made the Monarch one of the most common–and easily the most researched–species of Lepidopterans in North America.

Some of the intrigue lies in the Monarch’s miraculous 4-stage life cycle and how easily and intimately we can observe it in real time. Many of nature’s most breathtaking phenomena–the stunning colors and lifeforms of coral reefs, herds of stampeding mammals, Alaskan salmon runs, remarkable biodiversity at dry plains watering holes, etc., happen well out of our view and are known to us only through television footage from distant lands. But the Monarch goes through not one, but two, truly incredible transformations, changing from one form to a seemingly unrelated one, right under our noses. How many of us have watched in stunned awe as that beautifully tiger-striped caterpillar attaches its silk onto a surface above and begins to writhe its way out of its skin, morphing from larva to pupa in a matter of mere minutes? Just as mind-blowing is the emergence of a fully-winged butterfly from that lime green chrysalis roughly twelve days later. Not only do these inexplicable metamorphoses challenge our very concepts of time and being, but they offer existential hope that one can always transform any situation into a ‘new and improved’ one.

One would think, given our widespread fascination with its superhero migratory capabilities, the sheer magnitude of its wintering roosts, and the amazing transitional stages of its lifecycle–not to mention the remarkable beauty of its adult form, that taking care of the health of our native Monarch populations would be a top priority. Not so. What we’ve been experiencing in 2020, with one devastating event after another, has been the state of affairs for several decades now in the Monarch world. And, of course, we are primarily to blame. Under our watch, Monarch populations have declined by roughly 90% over the past twenty-five years. Because the vast majority of the insects tend to congregate in tight quarters during the winter, at less than a dozen sites in Mexico, each smaller than a football field, annual populations estimates are made at that time of year. The data, not unlike many of the graphs we’ve seen recently about COVID-19 cases, has occasional spikes (2018 was a relatively good year for Monarchs) and valleys (most recently, a 2012 heat wave in the American midwest killed off large numbers), but the overall trend has been steadily downward.

Like most population dynamics, the declining numbers are a complex result of several environmental stressors, all piling on at once. Each, of course, is primarily, human-induced. For a while, scientists believed that increased hazards along the Monarchs’ migratory routes were causing abnormally high mortality rates, although that theory has been largely debunked, based on Monarch Watch‘s recent analysis of almost 1.5 million tagged butterflies over a period of more than fifteen years. Instead, the downward spiral seems to be more closely tied to dramatic decreases in the abundance of milkweed, the sole host plant for Monarch caterpillars. Modern agricultural practices make heavy use glyphosate herbicide to control weeds and reduce the need for tilling. Glyphosate has also gained popularity as a means of controlling roadside weeds, among them, milkweed. Because of their extreme dependence on this one plant and their unusually restricted wintering range, Monarchs are far more vulnerable to severe events related to climate change than are most insects. One unseasonal winter storm, drought conditions during their migration period, a cold snap that delays spring departure from Mexico, an ill-timed hurricane during fall arrival . . . any number of extreme weather events can wreak havoc on Monarch numbers. As temperatures slowly rise world-wide, such potentially catastrophic events are only becoming more common.

Monarchs are clearly in trouble.  But it’s not too late to get involved in the efforts to bring them back.  During these waning days of summer, when we’re still largely sheltering at home, why not begin making plans for how you can make your own yard more Monarch-friendly? Grow milkweed or nectar plants that will attract butterflies. Research–and get involved in–some of the Citizen Science projects that are monitoring the latest trends in the species’ population size and range distribution. Advocate for organic farming practices and encourage friends and neighbors to stop using insecticides and herbicides. This is not some distant environmental crisis in the arctic, deep in the ocean, or in far-away jungles. The plight of the Monarch is happening in our own backyards, and we CAN do something about it. What better time to start than in 2020? In a year so full of negatives which seem beyond our control, why not create some small positives, which could have far-reaching impact, from here to central Mexico?!? For a few good places to start, see:

 

–BR