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Cristina Eisenberg

Following the High Ridge

            The fire ripped upslope through the thick aspen forest, leaping marshes and scouring openings that contained small meadows still soggy from recent snowmelt. It devoured saplings and shrubs and made wet-trunked aspen sizzle, immolate, and implode. Belching thick, white smoke, the ragged fireline climbed toward the spruce-fir belt just below a talus slope, leaving a wake of xylem turned to ashes. Intended as a “controlled burn,” it had been carefully staged by managers in Waterton Lakes National Park, Alberta, just north of the US/Canada border, to safely mimic the ecological effects of wildfire. This landscape, which some refer to as the “big wild,” lies on the east slope of the Rockies, north of Glacier National Park, Montana. It contains grizzly bears, wolves, wolverines, and other beings the likes of which have not been seen for decades in much of North America. Indeed, this landscape was perfectly wild with one critical omission. It had been nearly one hundred years since the last wildfire had been allowed to run unfettered through here. While multiple wildfires had been accepted and even welcomed in Glacier, the fire-phobic Canadian government had only recently begun experimenting with it in places beyond the margins of civilization.
            As fires go, this controlled burn, called the Y-Camp Fire in remembrance of a long-decommissioned camp, was supposed to be modest and well-behaved. Managers ignited it in early May 2008 in the Stoney Flats grassland, along the east shore of a small, teardrop-shaped glacial lake, with drip torches and fireballs lobbed from a helicopter. The Stoney Flats, named for the Stoney Indians who used to pitch their tepees and hunt there, comprises some of the most heavily trammeled elk winter range in the park. In January one can typically see a thousand cow elk grazing grasses and browsing on the aspens that hem the prairie. Before the fire, beyond the prairie the aspen parkland had unfurled in a shimmering, vivid green cloak up the shoulders of Sofa Mountain and Mount Vimy, to where the spruces and firs began, their inky spires sharply demarcating the horizontal ecotone between parkland and montane regions. Over the previous half century, the aspens had been moving ineluctably downsloap, encroaching on the grass. The Canadian government had identified this grassland as a precious, irreplaceable natural resource: one of the last patches of intact prairie left in that country. There, as elsewhere, the plough blade had plundered the pelf of the continent and urbanization had completed the job.
            Fire, an elemental natural force, creates resilient, healthy ecosystems. It stimulates powerful nutrient surges, opens choked forests, and enriches prairies by singeing the tops off senescent grasses and enabling fire-adapted plants to sprout and grow vigorously.1 As in similar ecosystems worldwide, the grasses and aspens in Waterton had co-evolved with fire. Across the ages in North America, every several hundred years ancestral wild burns had torn wantonly across millions of hectares. First People had purposefully complemented those great wildfires by setting smaller ones seasonally to improve animal habitat and plant health.2
            In the seventeenth century, Europeans settlers brought to North America worldviews that called for dewilding the continent: systematically eliminating fire, predators, and tenebrous woods.3Mid-nineteenth century Romantic Era voices such as Thoreau (“In Wildness is the preservation of the world.”) alerted us about our folly. But not until the last half of the twentieth century did we being to do something about it, thanks to visionaries like Aldo Leopold, who offered a new land ethic that called for living more rightly on the land.4 Today, by returning fire and predators to landscapes, and by protecting relict stands of old-growth forests, we are rewilding North America—reversing the ecological wreckage wrought by earlier generations. While today’s controlled burns are a pale simulacrum of those ancestral wild burns, occasionally a fire defies control and transmogrifies into a beast.
            For a controlled burn, the Y-Camp Fire was a doozey that ravenously consumed 1170 hectares of aspen forest before sputtering out when it hit a peat bog. Because they had set it when the forest was still damp from snowmelt, park administrators hoped it would tractably burn a few dozen hectares—fire dewilded, its benefits safely harnessed for the benefit of all. But an unexpected sustained blast of fifty-mile-per-hour prairie wind had rapidly eliminated any semblance of civility, changing this into the most successful “controlled” burn in park history. This unintentional holocaust fulfilled some managers’ secret subversive desires to see fire once again rule this landscape, as it had for millennia.
            I am an ecologist who studies relationships in food webs termed trophic cascades. Trophic refers to anything related to the food web, while trophic cascades refers to energy movement driven by predators. This dynamic resembles a waterfall and involves top-down ecosystem regulation, in which predators have a controlling influence on prey abundance and behavior at the next lower level, and so forth through the food web. Remove a top predator, such as the wolf, and elk grow more abundant and bold, consuming vegetation (called herbivory) unsustainably. Intensive herbivory can lead to elk literally eating themselves out of house and home and, consequently, to loss of biodiversity and ecosystem destabilization. Lacking top predators, ecosystems support fewer species, such as songbirds and butterflies, because the plants that create habitat for those species have been over-browsed.5 Fire contributes positively to these dynamics from the bottom-up, by stimulating plant growth. Thus, an ecosystem populated by both wolves and fire is far more productive in terms of plant growth, thereby harboring more species than one with wolves in it, but no fire.
            For the past four decades, an intense dialectic argument about whether ecosystems are regulated from the top-down versus from the bottom-up has split the scientific community.6Science often advances dialectically, perhaps because human nature compels us to find simple explanations. However, I argue that nature is never so simple.
            Trophic cascades in the northern Rockies are anything but linear. After a half-decade of sedulously tracking wolves, fire, and elk across landscapes and measuring aspen growth, what I’ve found can best be described as a fractal trophic spiral dance that defies tidy explanation. Models crafted by systems ecologist C. S. Holling forty years ago depict the trajectory of prey responses to predators in undulating, spiraling, swaying linear motifs called isoclines. These motifs can be amplified or dampened by unexpected environmental forces beyond human control, termed stochastic effects, such as a hard winter or drought.7 This trophic spiral dance can also be influenced by the more predictable effects of too many humans in a landscape or disturbances such as wildfire. Top-down forces shape the web of life via predation. But bottom-up, or nutrient-based forces, such as fire, equally shape ecosystems. These two keystone forces interweave to make the fractal patterns that Darwin so graphically described as nature’s tangled bank.8
            For the past four years I have been working with colleagues to measure the Y-Camp Fire’s tangled ecology. Each August and September I bushwhack into the fire zone with our field crew. Bearing thirty-pound packs that hold the tools of our trade—clinometers to measure slope and aspect and increment borers to core trees—we navigate through nearly impenetrable jackstraw snarls, past the blackened bodies of standing dead trees (termed snags), and through the thousands of supple, straight-trunked saplings that have sprouted since the fire. Our boots and hands smutched with soot, we painstakingly document post-fire response, which includes biodiversity, aspen growth, elk herbivory, and wolf use of the area. This entails examining the overarching forces that influence aspen communities, such as climate and human ecology, and the vicissitudes of our complex relationship with wolves. For immediately outside the park lie ranching communities replete with the charged husbandry and emotional issues that come with living in a place filled with wild creatures sharp of tooth and claw. In doing this research, I have found that it takes both scientific and artistic imagination to parse the fractal tophic web embedded in this wild landscape.
            In a somewhat obscure essay about a book of Audubon’s drawings written for the New York Times Book Review, eminent Russian novelist and lepidopterist Vladimir Nabokov asked, “Does there not exist a high ridge where the mountainside of ‘scientific’ knowledge joins the opposite slope of ‘artistic’ imagination?”9 To Nabokov’s question, my Waterton research has inspired me to add: And what might we learn there about resilience of whole ecosystems and of the human spirit?
            Resilience is the capacity of ecosystems and human hearts to heal under adversity. Panarchy, a concept integral to contemporary systems theory, compels an interdisciplinary discourse on change and resilience that considers the interactions of humans in nature via socio-ecological systems. Nature is constantly in flux across various scales and hierarchies. Panarchy draws from the Greek god Pan to describe wild, unpredictable change, adaptive evolution, and cyclic system renewal. Energy extraction, fire suppression, timber harvest, and predator removal precipitate change and myriad unexpected consequences.10 This disruption of natural processes is exacerbated by the concept of humans as apart from nature concocted by seventeenth century empiricists such as Descartes and later, inadvertently, by the Romantics, who enshrined nature.11 Contemporary environmental philosopher Timothy Morton posits a more enlightened perspective, termed dark ecology, which brooks no separation between humans and nature. He roots his philosophical construct in the arts, which hold powerful sway over how we perceive nature.12
            While scientists can provide the theoretical and empirical underpinnings to create a more sustainable world, it takes the arts to help us imagine and manifest this vision. As a scientist and writer afield, I have followed Nabokov’s high ridge to study the ecological effects of wolves. In doing so, I have learned that sustainability requires a worldview that embeds humans in nature. This perspective can lead to a nexus of the sciences and arts that overcomes the limitations of both to more effectively open people’s hearts and minds. And if the parnarchists are correct, it can lead to renewal that flows through communities like a Moebius loop, turning back on itself. Years afield have given me hope.
            My lessons in dark ecology began long before I became a scientist. For nearly two decades I have lived with my family in a cabin in the north Montana woods. From our cabin it is possible to walk through the roadless mountains due east for 125 miles without encountering anything but wilderness well-populated by grizzly bears and wolves. On our land my family and I often find wolf-killed deer and elk so fresh that their blood is still wet on the forest duff. These experiences have inspired my science, which fundamentally is about quantifying wildness and how rewilding nature creates more resilient ecosystems. Environmental writer George Sibley refers to this as the apotheosis hypothesis,13 the radical ecological concept that only by coexisting with keystone effects such as fire and wolf predation can humans foster renewal.
            The Smokey the Bear approach to fire management and the shoot-shovel-and-shut-up mentality so prevalent in the West, i.e., the notion that the only good predator is a dead one, counter the apotheosis hypothesis. Nevertheless, fires and predators still range rampant and wild in the remote corners of the West. Court and spark. Panarchy, a theory based on unexpected consequences and lack of hierarchy meets the apotheosis hypothesis head-on in places like Waterton, where keystones touch all, creating astonishing cascades of change.  
            How does one make sense of it all? Through the intersecting isoclines of science and art on Nanokov’s high ridge, where both are at equilibrium. It is there that we can begin to understand this dark ecology and why beyond empiricism, engagement of the heart is the sine qua non of sustainability. Beyond creating a deeper understanding of systems theory and food web processes, I hope to help find pathways to our collective salvation as species who share this earth household—human and non-human alike.
            I first explored the aftermath of the Y-Camp Fire in early August, three months after it had been ignited. From a distance I could mostly make out the devastation: charred snags and moribund survivors still hanging on, like critically ill patients. But when I glassed it with my spotting scope I could see that it had been a mixed-severity fire. While some patches had burned so hard that all that remained was bare mineral soil, others had been licked lightly by the flames. And when I walked into the fire zone, slipping on deadfall, I was amazed to see so much life: thousands of sprouts erupting from the ashes—death begetting life.
            Due to impenetrable marshes, only one viable footpath led into the fire zone: the Wishbone Trail—a shoestring thickly palisaded by aspens and shrubs. I dubbed this trail, in places so narrow that had I extended my arms I could have touched the trees on both sides, the Bear Gauntlet, due to the many bruins I had met there while counting songbirds to measure biodiversity. The bears (particularly grizzlies) were browsing succulent cow parsnip tops in summer and sweet berries in autumn. Peacefully foraging on either side of the trail when I entered their sanctum, they had always been far more polite than humans would have been had I barged into their homes at 3 a.m. But more than a bear gauntlet, the Wishbone Trail was one of  Waterton’s most heavily trafficked carnivore paths. On it I often found territorial markers deposited blatantly every few yards: bear, cougar, and wolf tracks and scats. The wolf activity interested me most, central to my research about keystone effects in food webs.
            Each year I invite local ranchers and arts scholars to join us afield. Most years we are graced by the company of John Russell and Valerie Haig-Brown, whose Hawk’s Nest Ranch lies on the northeastern park boundary. John’s great grandfather homesteaded this land, and his family has lived there since. A veteran wildlife biologist who specializes in caribou, he has long modeled and advocated ranching sustainably with predators. In a system with so many grizzlies and wolves, John walks the walk. He knows every corner of the Stoney Flats intimately, having played there often as a child, and seldom experiences cattle depredation on his ranch. And he recalls a wolfless time five decades past when there was far more grass and far fewer aspens than now. His partner, Valerie, an author and editor, brings to the field superb naturalist skills. She honed her fine sensibility of the aesthetic and the pragmatic across three decades of living in a place where arctic blasts can unexpectedly drop the mercury to forty below and snow often falls horizontally, driven by the prairie wind. As they helped us measure aspen growth and the wounds left by the mouths of hungry elk, we talked about how we might find working solutions to the “varmint question,” as Aldo Leopold put it as a rookie forester.14
            This year we discovered scores of bear tracks and dinnerplate-sized, berry-laden scats—but almost no wolf sign in our study area. The ranchers had been at it again. In Alberta wolves have never been protected, and indeed, landowners are legally entitled to shoot them within five kilometers of their land, for any reason. Given that, it is a miracle any wolves exist, let alone a pack—the Belly River wolves, who have stalwartly denned in Waterton since the early 1990s. And so we tracked them from August into September, in all the park’s wolfen places. As frost began to rime the river and the grizzlies became hyperphagic, we ventured into hidden wolf dens, ambled along riparian point bars, and combed rendezvous sites where the pack typically rested with their pups. In sum we found one ancient, moldy wolf scat, two fresh ones, and two adult tracks in a place where other years we had found hundreds of wolf tracks pressed into the mud. On the Wishbone Trail, a remote camera recorded two images of an adult male wolf, looking fit but lonely.
            As summer turned to autumn, I also had the good fortune of being joined by Ecopoetics editor, poet Jonathan Skinner, a Cornell University Fellow, whose interest in the soundscape, a term coined by Canadian composer R. Murray Schafer,15 had brought him to our study area. He was specifically interested in what he referred to as the “poetry animal” and prosody that considers how the sounds of poetry can be grounded in nature. As Jonathan helped us measure aspen and track wolves, his reflections on the human and non-human animal and how all of us are embedded in nature enriched our work tremendously.
            John’s pithy revelations on how depredation could be prevented quite simply by tending sick stock; Valerie’s perspectives on finding hope and renewal on the proverbial high ridge; and Skinner’s fresh insights on prosody and dark ecology, all comingled to bring my field season to a bittersweet close. The smoky wet scent of fallen leaves and voices on the wind: ragged bugles of rutting bull elk, and a faint (could it be) tenebrous howl from deep in the Belly River Valley, brought home for me the principal lesson of autumn, which was not, after all, about ripeness.
          Like the fractal food webs I study, it takes fractal thoughts and networks of ideas to find a way forward. And the way forward lies along that high ridge, where panarchy meets the apotheosis hypothesis to form a bright chimeric hope.


1Agee 1993

2Kay 2000

3Nash 2001; Coleman  2006

4Thoreau 1862 ; Leopold 1949

5Eisenberg 2010; Terborgh and Estes 2010

6Estes et al. 2011

7Holling 1973

8Darwin 1876

9Nabokov 1952; Pyle 2000

10Gunderson and Holling 2002

11Nash 2001; Morton 2009

12Morton 2009

13Sibley 2004

14Leopold 1919

15Schafer 2993


Literature Cited:

Agee, J. A. 1993. The Ecology of Pacific Northwest Forests. Washington, DC: Island Press.

Coleman, J. T. 2006. Vicious: Wolves and Men in America. New Haven: Yale University Press.

Darwin, C. 2010. The World of Charles Darwin, Volume 16: The Origin of Species 1876. New York: NYU Press.

Eisenberg, C. 2010. The Wolf’s Tooth: Keystone Predators, Trophic Cascades, and Biodiversity. Washington, DC: Island Press.

Estes, J., J. A. Terborgh, J. S. Brashares, M. E. Power, J. Berger, W. J. Bond, S. R. Capenter, T. Essington, R. D. Holt, J. B. C. Jackson, R. J. marquis, L. Oksanen, R. Oksanen, R. T. Paine, E. K. Pikitch, W. J. Ripple, S. A. Sandin, M. Scheffer, T. W. Schoener, J. B. Shurin, A. R. E. Sinlciar, M. E. Soule, R. Virtanen, D. A. Wardle. 2011. Trophic downloading of plant earth. Science 333:301-306.

Gunderson, L. C., and C. S. Holling. 2002. Panarchy: Understanding Transformations in Humans and Natural Systems. Washington, DC: Island Press.

Holling, C. S. 1973. Resilience and stability of ecological systems. Annual Review Ecology and Systematics 4:1-23.

Kay, C. 2000. Native burning in western North America: Implications for hardwood forest management.” In pp. 19-27 of Proceedings: Workshop on Fire, People, and the Central Hardwoods Landscape, March 12-14, 2000, Richmond, Kentucky. GTR-NE-274. Radnor, PA: USDA Forest Service, Northeastern Research Station.

Leopold, A. 1919. Varmints. The Pine Cone 1919(1). The New Mexico Game Protective Association. Leopold Papers 10-6, Folio 1.

Leopold, A. 1949. A Sand County Almanac: And Sketches Here and There. Oxford: Oxford University Press.

Morton, T. 2009. Ecology without Nature: Rethinking Environmental Aesthetics. Cambridge:Harvard University Press.

Nabokov. V. 1952. “Audubon’s Butterflies, Moths, and Other Studies.” The New York Times Book Review, Dec. 28, 1952.

Nash, R. 2001. Wilderness and the American Mind. 4th Edition. New Haven: Yale University Press.

Pyle, R. M. 2000. Walking the High Ridge: Life as a Field Trip. New York: Milweed Editions.

Schafer, R. M. 1993. The Soundscape. New York: Destiny Books.

Sibley, G. 2004. Dragons in Paradise: On the Edge Between Civilization and Sanity. Frisco, CO:Mountain Gazette Publishing.

Terborgh, J., and J. A. Estes. 2010. Trophic Cascades: Predators, Prey and the Changing Dynamics of Nature. Washington, DC: Island Press.

Thoreau, H. J. 1862. The Atlantic Monthly 9(56).