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CHAPTER 3

Rediscovery

By the early 1980s, 412 preserved black-footed ferret specimens were known to exist in museums, and Elaine Anderson tried to hunt down each one. She eventually created a map of dots showing the collection points of specimens that dated back to the 1880s. The map she came up with roughly tracked the extent of the known range of three prairie dog species (the Gunnison’s, white-tailed, and black-tailed), bounded by Texas and Northern Mexico to the south and by Montana and southern Saskatchewan to the north. The black-footed ferret was a uniquely North American species.

Even prior to the loss of what was known as the last wild ferret population, in Mellette County, South Dakota, in 1974, because of the large potential range map and knowledge of how secretive the species was, some people still harbored hope that another ferret population would be discovered. Tim Clark was one of them. In 1976, after completing his dissertation on prairie dog ecology, with Tom Campbell he created the Biota Research and Consulting firm—a generic title for a small and highly specialized group that focused their efforts on the goal of being the ones to rediscover black-footed ferrets.

Rediscovery of a black-footed ferret population was the kind of event that would make you a celebrity overnight. For a young scientist, it could kick-start a research program and form a funding platform that would last for years if not decades. A hunt that, because of the black-footed ferret’s endangered status, had to begin with a permit from the U.S. Fish and Wildlife Service.

Mr. Ron Nowak

Office of Rare and Endangered Wildlife

U.S. Fish and Wildlife Service

Department of the Interior

Washington, D.C.

Dear Mr. Nowak:

I am currently making plans for the 1976 black-footed ferret search in Wyoming. As you know my work over the last two years was an extensive search and yielded several localities where reports of ferret sightings are concentrated. What I plan to do this year is conduct an intensive search in one or more areas. The first two areas I would like to thoroughly examine are prairie dog concentrations 1) along Powder River and its principal drainages in NE Wyoming, and 2) Big Sandy BLM area of SW Wyoming.

In a detailed report which I sent your office in late 1974 I discussed the limitations of employing the techniques used in South Dakota [spotlighting] in the sagebrush areas of Wyoming. As a result of this presentation, I would like to as part of this years search to make application to try to live trap ferrets in these two areas. I would use #202 Tomahawk live traps. These are the same design I’ve used over the last year on my pine marten study in Grand Teton National Park.

If a ferret were captured I would follow these procedures: 1) Wyoming Game and Fish biologists and wardens from the area, along with U.S. Fish and Wildlife personnel and BLM biologists would be notified of the find, 2) they would be invited to come to the capture site to observe the ferret, and 3) the ferret would be released in their presence as soon as possible at the capture site. This procedure would conclusively demonstrate the presence of a ferret!

Sincerely,

Tim W. Clark, Ph.D.

Over the following years, Clark and Campbell’s personal mission extended beyond just Wyoming. The search for a remnant ferret population eventually led them to visit a total of eleven states, spending long nights on the prairie searching for tracks, trenches (where ferrets have excavated a prairie dog burrow by kicking dirt out a four-foot stripe of loose dirt), any kind of ferret sign. They surveyed local biologists and took to the air to search for potential large prairie dog colonies, working on the bottom-up hypothesis that if they could find a large prairie dog colony, they might just be able to find a place where ferrets were able to sustain themselves—corners of the prairie where maps were blank and others might have forgotten to check. After exhausting their hunches and with no individual success, they eventually cast their net wider by offering a $250 reward to anyone with information leading to a confirmed ferret sighting.

At the same time, federal biologists were also looking, but with the opposite intent of Clark and Campbell. Under a requirement of the Endangered Species Act, the U.S. Fish and Wildlife Service was charged with confirming the extirpation of ferrets—a political maneuver to ensure that should an area be developed, industries, landowners, and state and local governments could go about their pursuits without concern of lawsuits brought about by affecting the endangered black-footed ferret. Thus, prior to any type of land development, federal biologists like Max Schroeder, Dennie Hammer, and Steve Martin were charged with surveying and declaring the absence of ferrets. They were issued pickup trucks and dispatched to federal lands across the Great Plains to survey and confirm that nothing of legally protected status was going to be plowed over and away. They often tried to cover thousands of acres at a time ahead of the exponentially increasing demand for surface mining, the destructive beast of energy and commerce that scraped away the life of the land to get at the carbon underneath, forsaking one source of carbon for another, more densely packed and able to be burned. After what must have seemed like endless nights searching for ferrets with spotlights, effort reports were filed, sections of the map were marked off. Hope for the existence of black-footed ferrets was decreasing by one large swath of prairie at a time.

• • •

Around the same time, Michael Soulé and Brian Wilcox convened the First International Congress on Conservation Biology in 1978 in San Diego. Although the concept of conserving species had been around for decades in the United States, and for centuries in Germany and India, never before had ecologists taken such a proactive stance toward the protection of the natural world. They took a step away from hard lines of experimental science and reasoning toward a field that blurred the lines between advocacy and the more traditional scientific objectivism. As Soulé and Wilcox would later define the field, “Conservation biology is a mission-oriented discipline comprising both pure and applied science.” It blended traditional biological and ecological sciences with economics, sociology, and education, all in an effort to preserve species in the face of human persecution that was happening at local and global scales.

The urgency of the field was unique, controversially setting a framework within which scientists could enter into the realm of management for the sake of protecting what they study. As tropical ecologist Daniel Janzen would later advocate, “If biologists want a tropics in which to biologize, they are going to have to buy it with care, energy, effort, strategy, tactics, time and cash. . . . If our generation does not do it, it won’t be there for the next. Feel uneasy? You had better. There are no bad guys in the next village. They is us.” Scientists could no longer take the high road and claim that extinction is a natural process, part of Darwinian evolution, and move on to studying the next biological phenomenon.

For a discipline that emphasizes the conservation of biological diversity (the term biodiversity would not be adopted until 1988), extinction was the dirtiest of words. Many of those attending the San Diego meeting had worked on island systems or were still focusing their thoughts on the theory of island biogeography that had been developed by Robert MacArthur and E.O. Wilson a decade earlier. The influential theory was that the risk of extinction for a species on an island is a function of the size of the island and its isolation from other suitable islands. There was a corresponding belief that on the mainland, habitat fragmentation (in which humans removed habitat and further divided the landscape) similarly affected species. If we isolate a species on one of these virtual islands, such as a patch of forest surrounded by corn fields, the probability of that species going extinct increases. The smaller the patch, the worse off a species would be.

To avoid losing these “island” populations and risking extinction, ecologists began trying to identify critical population sizes to avoid extirpation. Mathematical models were developed for an individual species or population that, in their simplest form, were projections of the population into the future based on historical rates of births and deaths. But there was a need to account for a number of obstacles that could make small populations prone to extinction. Small populations within an island of habitat are more vulnerable to unpredictable events like floods or catastrophic fires.

For his dissertation research in 1978, Mark Shaffer developed a formula for predicting the minimum population size of grizzly bears to withstand such unpredictable events, which he termed the “minimum viable population size” (MVP). Over time, others would add to the complexity of such MVP models by including long-term detrimental effects like decreased reproductive output as a result of inbreeding and other factors. The product was hard numbers that could be used by wildlife managers to outline how many animals they needed to maintain, similar to agricultural balance sheets used by cattle ranchers to balance predicted losses against predicted gains, trying to stay in the black. But more than that, by experimenting with the numbers in the model, scientists could begin to say what factors needed to improve to keep the species viable. How would the population respond to a year of good rain that would perhaps result in a sudden 30 percent increase in juvenile survival? What would happen if we stopped a hunting season and were able to decrease adult mortality by 10 percent? These were hard numbers rather than sentiments to bring to politicians and the public when trying to maintain or recover a species.

The risk of species loss and the value in conserving rare populations also were brought to the forefront of public policy. The Endangered Species Act of 1973 (built on the backs of previous acts of 1966 and 1969) was amended to require not only listing of threatened and endangered species, but also designation of critical habitats and development of population recovery plans for those listed species. The National Forest Management Act of 1976 required the U.S. Forest Service to “provide for diversity of plant and animal communities based on the suitability and capability of the specific land area.” In effect, this made national forest managers responsible for maintaining viable populations of native species in their planning areas. Given that endangered and threatened species were typically most at risk of loss, the emphasis was put largely on maintaining or increasing their small populations.

The theoretical and political pieces were coming into place for the conservation of black-footed ferrets, should they ever be rediscovered and brought back from extinction.

• • •

On the morning of September 26, 1981, John and Lucille Hogg were having breakfast in their ranch home, an unassuming white-painted house in the center of a moderately sized ranch in the open, rolling hills and sagebrush flats west of Meeteetse, Wyoming. Up and down the valley the bustle of summer had ended. The rush of growing, irrigating, and cutting hay for the winter had given way to winter preparation. The cows and their calves were coming back into the corrals on homesteads and off the federally leased summer range. Daily chores switched from fences and farming to feeding livestock and preparing for the calving season, assessing the summer’s alfalfa hay crop, and calculating whether there was a need to buy hay to make it through the winter.

The ears of a sleeping rancher must be finely tuned to the sounds of the outdoors, keen to the sound of a bawling cow in early labor, even through the walls of a house in the middle of the night. Lucille Hogg hadn’t slept well because their Australian cattle dog, Shep, was barking and growling outside in the middle of the night. Lucille tossed in bed, settling on the thought that the dog was just learning another lesson on why to steer clear of porcupines. Knowing that there was little she could do in the middle of the night to pull out the hooklike barbs, she decided it could be dealt with in the morning, so she fell back asleep.

Over breakfast, Lucille told John to check Shep for porcupine quills and inspect the damage before the quills corkscrewed too deep into his muzzle and a trip to the vet was in order. Stepping out the front door, John noticed Shep was intact and uninjured, ready for the day. On the front stoop he’d left a carcass, the likely victim of his nighttime ruckus left for show to his owners. As John peered down at the thin carcass, his first reaction was that he had no clue what Shep had dispatched. It was a buff-brown animal with black markings on its paws, face, and tail. Perhaps it was an oddly marked pine marten that had come down from pine forests of the Carter Mountains to the north. Regardless, it looked interesting and attractive enough to pay to have preserved, and John took the specimen to Larry LaFranchi, the local taxidermist. Having stuffed more than his fair share of pine martens, Larry immediately recognized the animal as a black-footed ferret and called Wyoming authorities.

A ranch dog had succeeded where so many professional and backyard biologists had failed, offering a humbling and at the same time hopeful sign that the human footprint had not touched everything. Shep’s singular finding hinted that there were places left forgotten, little understood, where even the most sensitive of species could still persist. A second chance to perhaps learn from these animals and make up for our errors of the past, maybe even resurrect the species.

Within days the State of Wyoming held a town meeting in downtown Meeteetse, where rumor of the find had spread. Why had black-footed ferrets persisted here, on the very western boundary of the prairie? A single isolated dot on the western edge of the historic range map Elaine Anderson would develop that was based on all known museum specimens. Species are supposed to decline from the outside in, shrinking down into the middle where a small refuge remains. This small town of Meeteetse, Wyoming, just south of the more famous Cody, Wyoming, and Yellowstone National Park, was outside the area most thought to survey. But questions of why were secondary to questions of whether there were more, and how many. Wyoming Department of Game and Fish biologists started the meeting by reporting the details of the find and asked the audience if anyone had seen a ferret. Immediately Doug Brown volunteered that he had seen a ferret while working on the Pitchfork Ranch.

In the small ranching community of Meeteetse, stories of where ferrets remained were mixed with fear of what having an Endangered Species on your property could mean. There were rumors that federal restrictions could follow, brought on by enforcement of the Endangered Species Act—the type of legal maneuvering conservation groups still try to use to force the federal government’s hand to pressure private landowners about the use of their land. Despite that the precedent was rare and that most induced management changes occurred on federal land, the fear tactics create a persistent tension between conservation groups and private landowners, with the federal government in the middle. For independent ranchers, relying on the federal government as an effective moderator often wasn’t enough. Policies and administrations changed; ranchers were forced to live with the consequences. Despite the circulating paranoia, with counterculture bravery and vision (traits that, in future years, would be evident in almost every ferret conservation milestone), Jack Turnell, the owner of the Pitchfork Ranch, the Hogg family, and a handful of other ranchers in the vicinity ignored public concerns and allowed researchers onto their land.

Tim Clark and Tom Campbell rented an airplane to map the extent of prairie dogs in the area. They scanned the rolling, open sagebrush steppe grasslands of the Big Horn Basin around Meeteetse that are bounded to the west by the Absaroka mountain range that extend north into Yellowstone National Park. On the ground, federal biologists Hammer and Martin were conducting nightly searches for ferrets on the group of ranches adjoining the Hogg ranch. They walked or drove around the prairie, using spotlights to look for the distinctive green eye shine from the reflective membrane just behind the ferrets’ retinas, hoping that a curious ferret would stick its head out of a burrow. To improve the chances, they also used two search dogs trained to sit when they smelled the scent of a ferret. When one of the dogs smelled the faint aroma of ferret scat or musk and sat down by a burrow, Hammer and Martin, not seeing ferrets themselves but blindly hoping the dogs were on to something, would set live traps at that burrow and surrounding burrows.

On October 29, 1981, more than a month after Shep’s discovery, Hammer and Martin were checking traps in an area where dogs had found scent. Leaving the traps set, they returned to their vehicle and drove off into the night to continue their spotlight search. Looping back around toward their traps, at 6:20 A.M. they saw the flash of something running across the road in front of them and periscoping its head out of a burrow. They had never seen a ferret, but they thought it looked about right; with buff markings, it skimmed quickly across the prairie like a weasel relative. Hammer approached the burrow, and the ferret was still just inside the entrance, peering up from the shadows and chattering at him.

No human could take credit for rediscovering the species—that honor belonged to Shep—but few could have experienced the emotions of Dennie Hammer and Steve Martin. They experienced the career-defining moment of being the first people to see a live black-footed ferret in two years, after the last male died in captivity at Patuxent and the species was widely believed extinct. Perhaps more important, they were the first to hear the chatter of a live ferret in the wild since Mellette County seven years prior. Adrenalin mixed with panic as Dennie put his hat over the burrow while he rushed to get and set a trap. Walking up to the trap eleven hours later and seeing the ferret looking back at him, his thoughts must have been filled with that delicately marked prairie bandit. It was the almost mythical creature for which he had searched hundreds of hours across much of the western United States. This erased the ridicule from other university students who, when he said he wanted to study ferrets for his graduate degree, told Hammer he was trying to study dinosaurs. Then there was the thrill the next day of releasing the ferret that they had nicknamed “620” (after the time it was captured). They watched it scurry down the burrow after it was fitted with a small radio-transmitter collar and hoped it would stay alive so they could monitor its movements. There was so much to learn. Did ferrets here in the shortgrass prairie of Wyoming behave differently than those in Mellette County, South Dakota? Why were they here and nowhere else? And most important, how many were there? Now, finally, ferret research and conservation could begin again in earnest.

• • •

Hammer and Martin, along with telemetry specialist Dean Biggins and a handful of additional federal researchers, intensively monitored the movements of ferret 620 for the next month. They eventually found ten other ferrets in the area. Some of the mysteries of the black-footed ferret had been unlocked in the final days of research in Mellette County, South Dakota. Con Hillman and others had noted that ferrets were typically nocturnal and solitary, mostly visible in early morning or late evening. They found that adult females, on average, produced 3.4 young each year, and that the young typically first venture above ground as early as mid-July. They also learned that ferrets were most readily spotted in early fall when kits dispersed and mothers and their kits played above ground. They learned that ferrets were underground much of the winter, limiting biologists to monitor infrequent movements based on ferret tracks and diggings that could be spotted after a fresh layer of snow had fallen.

But there was still so much to learn. Because only a few ferrets were followed in Mellette County and none was observed to move between prairie dog colonies, it still was not known how and when ferrets moved between colonies. Little was known of their breeding behavior, whether females reared young alone or had help from males, how often they fed their young, or how many prairie dogs were required to sustain them. Were ferrets such efficient predators that they served as a sort of natural control for prairie dog populations, as C. Hart Merriam had predicted in 1902? Given that ferrets vanished from Mellette County, was a particular size and arrangement of prairie dog colonies required to sustain ferrets? There were still the questions of what role prairie dog poisoning had had on ferrets, and how many prairie dogs were required to support a self-sustaining ferret population.

Further, it was possible that ferrets in Meeteetse might behave differently than those in Mellette County because this newly discovered population was on the edge of the ferret’s supposed historical range. The ferrets in Meeteetse persisted on a colony of white-tailed prairie dogs, unlike the ferrets in Mellette County that lived on black-tailed prairie dog colonies. White-tailed prairie dogs were arid-environment specialists, primarily appearing in portions of Montana, Wyoming, Utah, and western Colorado. Lower rainfall meant less vegetation in both summer and winter, resulting in a species that evolved to live in more widely distributed social groups and lower densities. How did ferrets persist on sites having less prey? Did they need to travel farther, were they more competitive, and did they supplement their diet with other rodents or birds?

It was the advent of radio-tracking technology that allowed researchers to begin addressing many of these detailed questions for such a small, cryptic species. By the late 1970s, technology had advanced to the point that small transmitters could be attached with cloth collars to animals. Biologists had already identified the size, design, and weight of a radio collar that the close relative of the black-footed ferret, the Siberian polecat, could tolerate. They knew that ferrets would present a unique issue compared to other animals. Their small weight limited how large a transmitter they could tolerate without the ferret’s ability to move and hunt being hurt. Biologists knew that without a large battery, the transmitter would have limited range and lifetime. They knew that because a ferret spends more than 90 percent of its life below ground, getting a signal would be difficult at best, and it was more likely that they would have to scan continually, often in the middle of the night, for the chance to detect that a ferret had come above ground.

In addition to the technology encased within the plastic-coated transmitter capsule, for a tubular animal the design and tightening of the collar itself was critical. A collar needed to be loose enough to allow breathing and growth of the animal, tight and rugged enough to stay on, and made of cotton that would degrade so the collar would fall off over time as the battery died. This made the stress of placing a collar on a captured and sedated ferret that much more intense. Not only did you have one of the rarest animals in the world in your hands, you had to mount something around its neck that if done improperly could kill it. If it was too loose, you would risk the chance of the ferret slipping the collar, forcing a second stressful capture if you ever even saw the animal again.

For wildlife biologists, tracking an animal is typically a solitary affair conducted by a biologist with a hand-held antenna and receiver tucked under the arm, headphones sending out a hissing sound. The biologist listens for a faint beep as the antenna is panned around, and hikes from waypoint to waypoint, eventually honing in on the location of the animal and taking note of the location. Yet, because ferrets came above ground so infrequently, just detecting them required teamwork. Rather than sending a dozen biologists out onto the prairie throughout the night, three camper trailers, modified so that large directional antennas poked through their roofs, were placed on the highest points surrounding core prairie dog colonies in a triangular design. This required near-constant tracking by a team of biologists who spent hours hunched over within the trailers, rotating the antennas and scanning ferret transmitter frequencies, listening through headsets for faint electronic beeps in the hiss of static signaling a ferret had come above ground. Once a ferret emerged and was detected by one of the biologists, the biologist would relay the approximate location of the ferret to biologists in the other two trailers. When two or more trailers locked on to a ferret signal, they could accurately triangulate the location of the ferret. Over the span of weeks and months, researchers began to define the territories of individual animals, their activity patterns, and their behavioral interactions with other marked ferrets.

As a break from the trailers, researchers would swap their sedentary nightly duties and hit the sagebrush flats to find ferrets by spotlighting, searching for isolated animals on the peripheral colonies that were not already under radio-telemetry study. The researchers would move around on the prairie and capture the remaining few ferrets, recording their measurements and marking them with “passive integrated transponder” implants (PIT tags for short) injected just below the skin. These small, pill-shaped microchips are passive in the sense that they do not rely on a battery to transmit a signal like radio collars do, but instead require an outside scanner to pass within a few inches to relay a reading. With no bulky batteries to worry about, PIT tags last forever and provide a way to permanently identify individual ferrets. By finding and scanning the PIT tags of ferrets over the entire area, biologists were able to get a count of marked individuals. They could learn a minimum population size with which to assess the status of the population and follow the population through time to assess its viability.

With these tools, the small army of researchers learned that it was unlikely to see two or more ferrets together. The solitary ferrets seen above ground in January and February were likely males in search of mates, roaming their territory that overlapped one or more smaller territories of females. Seeing one male trying to maintain access and breeding rights to multiple females suggested to researchers that ferrets were similar to other members of the weasel family in having a polygamous mating strategy. Ecological theory tells us that in polygamous societies, a male has to produce as many offspring as possible to maximize his genetic lineage. This requires that males keep exclusive access to as many females as possible. It is a matter of quantity, but also quality, because females typically select the best habitat in which to raise their litters. Thus, by association, males that protect prime habitat also are likely to have access to the most females and to females that are most likely to successfully rear their young.

Guarding of mates by male ferrets reached a fever pitch in the mating season from January through mid-March. Then, after a forty-five-day gestation period, kits were born in a natal burrow. Contrary to many other carnivores, such as wolverines and otters that remain in a single nest chamber for the whole litter-rearing period, female ferrets would move kits to new burrows at regular intervals. The mother would carry them with her teeth by the scruff of the neck, one at a time, when their eyes were still shut and they were not yet mobile.

Meeteetse researchers found that females did all the caring for the young, protecting them from birth in spring through to independence in late summer. A mother ferret at first nursed her kits, staying below ground for long periods of time. She killed prairie dogs only occasionally for her own food, until June, when she started moving the whole family to a burrow containing a freshly killed prairie dog. By late July and early August, kits were old enough to have motor control and come above ground for periods of time during the night. They would be cautious at first, with only the boldest of a litter of three or more doing more than sticking its head above ground, and never straying more than a few feet from the safety of the natal burrow entrance.

By mid-August, kits came above ground almost every night. On 93 percent of nights to be exact, typically between 1:00 and 4:00 A.M. The kits stood by their natal burrows as the mother hunted for food, until the silence was broken by one of the litter starting a tussle by charging at another, back arched, mouth agape, tail frizzed. Spotlighters found the kits to be curious, peering up from burrow entrances when the spotlighters approached. The kits noticed that any foreign object placed by their burrow deserved inspection. The small flags the researchers used to mark burrows often induced a spontaneous fit of play. Young kits would lunge off the ground, reaching the flapping flag at the top of the two-foot wire flags and landing in a puff of dust. They seemed amazed that they reached so high after a childhood spent mostly below ground or within two inches of the flat prairie surface. Collecting themselves after landing, as the dust cleared they sometimes chased their own tails, perhaps out of curiosity about their rapidly growing bodies.

By late August, kits grew to be as large as their mother or even larger, and more independent. They dispersed from their mother’s territory by the end of September and the prairie dancers had gone away. They were solitary for the next few months as behaviors shifted from rambunctious play to the pressures of adulthood and survival. By November, the former kits and older adult ferrets were active above ground only for, at most, one to two hours per night. With so little to observe, researchers switched their monitoring from spotlighting to occasional snow tracking when fresh layers of snow fell, searching for slight pawprints leading between burrows in skiffs of thin snow blown like sand into small waves by the bitter prairie winds. Biologists found that during the harsh winter months, when temperatures dropped below freezing and when white-tailed prairie dogs slept below ground for weeks on end in a state of torpor, ferrets similarly slowed their above ground activity. During peak winter periods, ferrets would spend up to six nights and days below ground without moving to another burrow. But the clearest pattern to the researchers was also the one attribute that has been known the longest about this species since its first discovery and description: that black-footed ferrets almost never leave prairie dog colonies; as the prairie dog goes, so goes the ferret.

• • •

With the birth of conservation biology as a major scientific discipline, its participants formed a society in 1985 and soon thereafter launched an academic journal. The very first issue of the journal, Conservation Biology, published in 1987, opened with a four-page “progress report” by Tim Clark on the conservation of the black-footed ferret. He stated authoritatively on the first line that “black-footed ferrets are the most endangered mammal in North America.”

The remainder of the article painted a similarly grim picture. For what Soulé termed a “crisis discipline,” the black-footed ferret story of Meeteetse served as an ideal case study of conservation biology in practice. The series of events following rediscovery provided the classic example given in textbooks for the next several decades about how conservation biology requires skill sets from many walks of life to restore critically endangered species from the brink of extinction. And examples of ferret recovery efforts also demonstrated how failure to gain broad support and consensus on overall management direction can result in near-catastrophe.

In 1982, the year after rediscovery of ferrets at Meeteetse, researchers counted sixty-one individuals. That number increased in 1983 to eighty-eight and then again to 129 in 1984. The population was thought to be productive enough to exceed requirements of a minimum viable population. This meant that some ferrets could be captured and used as seed stock for captive breeding at the National Zoo, and once again at Patuxent. Yet because of political infighting between the State of Wyoming and a host of researchers and federal agencies, Wyoming decided that ferrets should not leave the state. Because no adequate facility existed in Wyoming to keep ferrets, let alone breed them in captivity, and because Wyoming insisted that any new breeding facility should be paid for by federal and private sources, capturing ferrets for captive breeding was put on hold.

Unfortunately, surveys by Meeteetse researchers found that by August 1985 there were only fifty-eight ferrets. Biologists feared the worst as the population continued to dwindle to thirty-one by September and to sixteen by October. There was great confusion over the cause of such a precipitous decline. Earlier that year plague was reported in the area, but studies of European polecats suggested that ferrets were likely immune to plague (an assumption that later turned out to be wrong; black-footed ferrets are actually highly susceptible to plague, as discussed in later chapters). Regardless, such a precipitous decline made the ongoing debates among state and federal biologists moot. The race was on to save the last few individuals in a last-ditch effort at captive breeding.

In October 1985, six of Meeteetse’s remaining ferrets were captured and transferred to a Wyoming wildlife research facility located in Sybille Canyon in the southern part of the state. Upon arrival, one ferret died of canine distemper virus. Then another died. Finally, because all six were housed in the same room at Sybille, the remaining four eventually contracted distemper and died.

A capture team was immediately sent to collect all remaining ferrets from the Pitchfork Ranch. Six more ferrets were brought to Sybille the following week. These animals did not die of distemper, but six individuals was hardly enough to start a captive breeding program. Certainly, such a number gave the captive breeders and ferrets only a small margin for error. But researchers knew that there was only a small chance that any more ferrets could have evaded capture and survived the canine distemper outbreak that was known to have spread through Meeteetse that year.

However, surveys in 1986 revealed that four individual ferrets survived in the core of the Pitchfork Ranch. There were two males and two females, which were monitored through the summer and found to produce litters of five kits each. Despite this glimmer of hope, by March of the following year it was decided that all known ferrets should be captured and moved to Sybille. In all, eighteen surviving ferrets were captured and taken into captivity. Some stragglers might have avoided this final capture effort, but they likely succumbed to disease or natural mortality in the coming winter or spring. A few might have lived as long as a year or two, but they would have been too few in number to persist and find each other to reproduce. All we know is that no more ferrets were seen in Meeteetse after March 1987.

With the last wild black-footed ferret at Meeteetse captured, something else was lost. Tim Clark paid the Hogg family the $250 reward he had promised for a confirmed ferret sighting, and there was still hope that rare ferret family groups remained hidden in remote pockets of the American West. During the thirty years since the Meeteetse rediscovery, the reward was increased to $5,000 and then to $10,000, but no remnant wild ferret populations were discovered. We now know that Shep found the last black-footed ferret population, and the species would likely have truly gone extinct, unnoticed without his help. Decades of searching has told us with near certainty what biologists already feared as they removed the last individual from Meeteetse: there were no other black-footed ferrets on the Great Plains. The fate of the species rested in a small number of captive individuals.