We live in a world of loss. As an ecologist I’m keenly aware of these losses. Endangered species worldwide face dwindling habitat and threats caused by an explosively growing human population and climate change. From an ecological perspective, rewilding, defined as landscape-scale conservation aimed at protecting keystone species, provides the most natural way to fight today’s runaway extinction. Rewilding means restoring natural processes. Put more simply, it means righting the wrongs we’ve done to the earth.
Keystone species are those whose presence in an ecosystem touches myriad others. In a Roman arch, if you remove the keystone, the arch collapses. So it is with keystone species in the natural world. This is because keystones improve habitat for other species. For example, by eating sea urchins, sea otters help kelp forests thrive, creating habitat for fishes and other marine organisms. By killing and scaring elk, wolves diminish elk pressure on sensitive trees and shrubs, creating habitat for woodland species. By urinating, bison fix nitrogen in the soil. With their horns they tear up the prairie earth, aerating the soil and keeping grasslands open and fecund, creating small-mammal habitat. However, it’s insufficient to have token numbers of keystone species scattered around the world and call it good. To be ecologically effective, keystones must be abundant and well distributed in all sorts of ecosystems. Yet today we struggle to define what that means, much less make it happen.
To complicate matters, humans have many ways of looking at rewilding. Some say rewilding means playing God—putting back species to repair the damage we’ve wrought to the earth. But there are consequences to playing God and accompanying hard questions. Just how wild is rewilded enough? Just how many wolves, grizzly bears, or bison are enough? And what do we do when there are too many? Some say rewilding means letting nature find Her way. Some say rewilding is about humility. Which is the opposite of playing God. Some say it constitutes little more than ecological hegemony. I say rewilding is all of the above—which creates the ultimate existential conundrum, as the stories I share below illustrate.
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In mid-May, three years ago, I’d just finished teaching a one-week rewilding course in Yellowstone National Park, Wyoming, at the historic Buffalo Ranch. After the class, I’d decided to hang out for another day, to relax. That night at the ranch bunkhouse, I opened a good bottle of wine, made elk spaghetti for supper from the meat of an animal I’d hunted the previous autumn, and shared this meal with the students who remained at camp. It had been cold all week, alternating between snow and freezing rain, typical blustery spring weather. We’d spent most of it gloriously afield, in the core of this famously rewilded system where humans had consciously reintroduced wolves in 1995 and brought bison back from extinction decades earlier. Ravenously hungry because of all the calories we’d been burning outdoors, we ate and ate. As we ate we traded wolf and bison stories and debriefed about what we’d learned in the past week.
Located at the east end of the broad, glacier-carved Lamar Valley, the Buffalo Ranch lies nestled at the base of one of the steep northern buttes that flank this valley. The US federal government established the ranch in 1901, when bison were down to 25 individuals in the park, to save this species from extinction. The bison rewilding ostensibly succeeded; there are now 5,000 bison in Yellowstone in two herds. This population grows 10 to 17 percent annually—ten times faster than the global rate of human population growth. Yet some claim that this rewilding perhaps succeeded too well, because the park contains such a small amount of bison habitat. Primarily grass-eaters, bison need open grassland. To make matters worse, managers must confine this herd to the park, to prevent the spread of disease to livestock outside the park. This means that Yellowstone bison aren’t truly or biologically “wild” bison (based on the scientific definition of what a wild animal is), because they’re essentially captive, not allowed to migrate or roam freely beyond the park boundary.
Today the Yellowstone Forever Institute uses the Buffalo Ranch as a field station, out of which they base environmental education courses like mine. Part of the Lamar Ranger Station field-camp complex, it consists of a bunkhouse, some cabins, a barn, and corrals. Beautifully restored, these buildings had been retrofitted as classrooms and student housing. Beyond infrastructure, the ranch makes an optimal classroom because it’s literally where the rewilding action is.
Some days wolves would run through camp, chasing elk. But it quickly became evident that the wolves had other things besides elk on their minds. The bison had just calved. Fuzzy, rust-colored calves gamboled wildly on the valley bottom, running around in circles. Given that some were less than a week old, they kept up with the herd amazingly well. But in a valley that contained a half dozen wolf packs, they were essentially wolf bait.
One morning we watched a pack of eight wolves move across the valley toward a large herd of bison, about 300 yards in front of the Buffalo Ranch. As part of a scheduled class activity on predator/prey behavior, we stood at the ranch entrance, safely watching the unfolding drama through spotting scopes. I was teaching my students how to do focal animal observations and interpret wildlife interactions. Park biologists joined us and shared their insights.
Yearling wolves were testing adult male bison. They’d approach a bison and begin trying to chase it. At first the bison would stand his ground, tail curled in a high crook—classic bison aggressive body language. Then he’d charge the wolves. As long as the wolves kept running, the bison would quickly stop his charge. But the minute the wolves stopped running, he’d resume charging, usually with greater intensity. The young wolves had figured this out and were also learning how hard they could push. While to these yearlings this was a game, there was also deadly purpose to their play; they were learning the art of hunting. Realistically, Yellowstone wolves seldom killed adult bison, which were dangerous prey. Instead, they took a small amount of bison opportunistically—killing the young, weak, and vulnerable. This meant those wolves had negligible overall impact on bison numbers.
As the yearling wolves continued to feint attacks on adult bison, thereby distracting the herd, the rest of the pack deftly isolated a calf. They killed it in seconds, tossing its lifeless body twenty feet into the air. As the calf fell to earth, the pack parted and the alpha female caught it cleanly in her jaws. She wore a radio-collar, which had enabled park biologists to determine that this was her first hunt since having whelped pups in late April. Physically depleted from giving birth and nursing, she badly needed the rich nutrients the plump calf provided.
The pack trotted a short distance off and let her have the carcass. She devoured it in less than ten minutes. A raucous chorus of howls ensued as she rejoined her pack mates, her snout bloody from the fresh kill. Nature red in tooth and claw is not for the fainthearted. I explained to my aghast students that such acts of predation were the reality of rewilding.
Another harsh reality of rewilding is that the bison had been multiplying exponentially, particularly since 2006, to the point that they’d exceeded the capacity of even a place as large as Yellowstone. Since they weren’t allowed to roam outside the park because they carried brucellosis and other diseases that could be transferred to domestic cattle, and since they had an innate urge to make 200-mile migrations, Yellowstone was a de facto postage stamp of habitat for them. Consequently, this ultra-high, confined bison population had depleted its habitat to the point that the grassland could barely sustain them. In the process the herd also had damaged habitat for other species, such as songbirds, small mammals, and insects.
What to do about too many bison? Because wolf predation was unable to keep the park bison population at a sustainable level, managers had to give away or cull approximately 15% of the herd each year. They offered a small number of live bison to tribes, but these animals often got stuck in legal red tape. Other times the tribes lacked the financial resources or infrastructure to keep these 1000 to 2000 pound mega-herbivores that were essentially untamable. The federal government provided treaty hunting rights on bison that stepped outside the park, but usually only around 400 bison were killed in this way, not enough to prevent a more formal cull. So managers set up a holding pen within the park, near one of the northern entrances, into which they herded bison. The bison were tested for brucellosis. If they tested negative, managers gave them to tribes such as the Assiniboine and Sioux, who live in northeast Montana on the Fort Peck Reservation. This reservation has the highest per-capita poverty rate of any Indian reservation in the US (58% compared to the overall US poverty rate of 9%). They shipped the bison to slaughterhouses where the tribes could pick them up. The tribes ate this precious meat and used the hides. Those animals sustained them the way bison had sustained their ancestors. In this manner, the park culled up to 1,200 bison annually, their meat keeping Native Americans alive. The number culled was equivalent to the number of bison that would’ve been killed by Indigenous people here 500 years ago as part of their subsistence lifestyle.
The conservation community was outraged by the slaughter. On the other side of the fence, intransigent ranchers took up arms when other options were proposed, such allowing bison to roam freely outside the park. Amid this political maelstrom, toward the end of his presidency Obama designated bison our national mammal. And these conservation icons kept producing calves, kept trying to leave the park, and kept being culled, because legally the federal government couldn’t allow them to range beyond the park boundary. It would’ve taken an act of Congress to do so, which hadn’t been forthcoming under the Obama administration, much less under the Trump administration. And so the cycle repeated annually, with no obvious resolution to this acrimonious rewilding battle.
Over our elk supper, we debriefed about rewilding, about predators and their prey, about the so-called balance of nature, which after all is but an illusion. We talked about what one does when there are too many individuals in a restored wildlife population—whether it’s ethical to “manage” them by continuing to play God and cull them. We talked about how life and death are part of the same continuum, how each act of predation sustains life. We pondered the role of hunting by humans ancestrally and today and where ranching fits into this now. There were no easy answers. Nevertheless, my students gave me hope that eventually we’d find a solution to this rewilding dilemma. We considered, for example, what would happen if bison were simply allowed to roam freely across North America, as they once had. As we filled our bellies with wild meat, we discussed that not a single confirmed case existed of bison passing brucellosis to cattle.
After dinner, I sat with my students in a reflective mood. I poured myself a second glass of wine and was about to take a sip, when a student who hadn’t been with us at dinner approached me and asked if I’d seen his best friend, who was also in the class. They’d traveled together from Oregon to the Buffalo Ranch. Lifelong friends, both had strong wilderness skills. I’ll call them Joe and Bill. Now in their forties, over the years they’d backpacked together for thousands of miles and were rewilding advocates. They contributed much to our class.
Joe said Bill had left a couple of hours earlier to photograph a bison skull behind camp, north of Rose Creek, which bounded camp. Bill hadn’t taken his backpack, which was unlike him, or his cell phone or any personal belongings, besides his camera. The sun was starting to set, the temperature dropping into the teens. Joe was worried that something bad had befallen Bill, who hadn’t taken his jacket either. I agreed, and we sprang to action.
Within five minutes, I grabbed my pack, park radio, safety equipment, and first aid kit, and convened a search-and-rescue mission. Accompanied by two park staff and Joe, I set off to find Bill. We had extensive wilderness rescue experience among us. Park rangers monitored our progress from below. We stayed in contact using radios, and wore headlamps, not so much to light our way, but so that people could see us from afar.
We crossed Rose Creek and headed straight up a butte called Ranger Hill. Racing the fading light, we bushwhacked through thick, waist-high sagebrush, calling Bill’s name and whistling for him. We fanned out, 50 yards apart, to cover more ground. And so we moved rapidly in the gloaming, calling and getting no answer, becoming increasingly concerned about Bill.
A half hour later, our radios crackled to life. Bill had shown up at the Buffalo Ranch. It turned out that he’d gone to photograph the bison skull, and then had hitched a ride with a passing wolf-watcher to go catch some wolf action, without letting anyone know his plans. He’d lost track of time, but was well. Elated and relieved, we came together for a hearty high-five, and headed downslope at a relaxed pace, weaving our way carefully through the tall, thick sagebrush.
And then park staff radioed us that four male bison were headed our way. The bison had been a mile and a half away from us in the vicinity of the historic Rose Creek wolf acclimation pen, one drainage west of Ranger Hill. They’d been hanging out there all week—we’d seen them a couple of days earlier, while we tracked wolves. Staff informed us that as we searched for Bill, the bison had begun moving slowly in our direction. Now they were coming on fast and could easily charge us. We fanned out again and began to run downslope toward the ranch, quickly putting some distance between ourselves and the bison, dodging big rocks and sagebrush along the way.
All at once I heard a bison about 20 yards behind me. Later I learned from observers below that it was the dominant bull, and that he’d singled me out. He made a sound that was a cross between a snort and a roar—like something out of a nightmare. It was the sound bison make prior to charging. Remembering the young wolves who’d been challenging male bison in the Lamar, I ran faster. I ran harder than I’ve ever run in my life, down this steep slope, a five-foot-tall slender woman of mixed-Indigenous blood wearing a heavy pack, leaping over enormous sagebrush clumps, big rocks, anything in my path. I didn’t have a choice. If I fell I’d be gored to death by a 2000-pound bison. I remember telling myself it wasn’t my day to die and that I couldn’t stop. I had a good mile to go before I reached the butte bottom and safety.
I was producing so much adrenaline that at one point I had an out-of-body experience. I became a raven flying over the Lamar Valley and could see myself running below, the bison not far behind me. I was a runner back then, so my deep-muscle memory kicked in and my legs knew exactly what to do. And so I ran in the semi-darkness, miraculously not tripping, my steps sure on the loose, friable soil. I ran without stopping until I got to Rose Creek. When I crossed the stream, I knew I was safe, because it created a psychological barrier between me and the bison.
I stopped to catch my breath. Flooded by adrenaline, I felt light headed and severely nauseous. I took a few moments to swallow back the nausea and calm my breathing before going to the bunkhouse and letting everyone know all was well. That night I slept peacefully, happy to be alive. The next day I drove 350 miles back to my Swan Valley, Montana home, feeling fey and having trouble thinking clearly, because my brain wasn’t working right from all the adrenaline. It would take two more days to clear it out of my system.
What had happened? I’d spent years living and working in ecosystems where there were more large carnivores than humans. I was an expert on human/wildlife conflict. Across decades of fieldwork my experiences had borne out that if one treated wild animals with respect, they tended to reciprocate. This bison attack was unlike anything I’d ever experienced. That he’d singled me out and come at me from a distance of a mile and half—for no apparent reason—mystified me. That he’d wanted to kill me made no sense.
One month later, I visited my friend John Russell, and got my answer. John was a wildlife biologist whose family had homesteaded in southwest Alberta, on the east slope of the Rockies. His family had led wolf and grizzly bear conservation in Canada over the past 70 years. I considered him one of my most trusted friends and mentors. So I told him what had happened in Yellowstone and asked why.
“Simple,” John said, “the bison was angry and he took it out on you.”
That year managers had culled 700 bison two weeks before I had arrived in Yellowstone. Regardless of the ecological rightness of the cull, that bull was mad at humans. No amount of frolicking calves could make up for the loss of so much of his herd. He was the dominant male, and he needed to make a statement. So this avatar of the wild had singled me out, a nerdy ecologist, and taught me a life lesson.
As John explained this, it made total sense. And I realized that this is what rewilding really means. Rewilding is about playing God and then having to deal with the consequences—with grace, humility, and wisdom. It means acknowledging that nature will take matters into Her hands. And that there are creatures and forces out there far more powerful than humans. It means that if we don’t pay attention to their lessons, we’ll end up dead.
It’s been three years. Far from traumatizing me, this experience catalyzed my work. Today I’m a member of the International Union for the Conservation of Nature (IUCN) Bison Specialist Group. I’ve been appointed to this group as a bison expert, to help advance recovery of this species. Specifically, I’m involved in supporting the free-ranging wild bison reintroduction underway in Banff National Park, Alberta, and the Badger-Two Medicine area of Montana, working closely with the Blackfoot Confederacy and other tribes, as part of the Iinnii Initiative (iinnii means bison in Blackfoot). I‘m passionate about bison conservation. And I aim to learn from these magnificent animals, the way our ancestors did, so that we don’t repeat some of our rewilding mistakes.
