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CHAPTER 4

Captive Breeding

US Route 191 crisscrosses the Rockies in a nearly straight line, heading north from the Mexico border at Douglas, Arizona. It is a 1,905-mile span of asphalt that passes through Arizona, Utah, and Wyoming before stopping at the south entrance of Yellowstone National Park, then starting up again at the west entrance of Yellowstone in Montana and finishing at the Montana–Canadian border. The last town of consequence before the border is Malta, located where north–south Route 191 intersects east–west US Route 2 just below the 48th parallel. An intersection of consequence because the similarly impressive Route 2 traces the Canadian border for 2,192 miles from Houlton, Maine, on the Atlantic coast to Everett, Washington, on the Pacific coast. Along its path, where Route 2 passes through the open plains of eastern Montana, it is called the Hi-Line, a flat, sparsely populated 402-mile east–west stretch of the globe named by the Great Northern Railway, which started bringing in immigrant families and exporting grain and livestock in 1887.

The Homestead Act of 1862 provided settlers with title to 160 acres of Montana land provided they built a house, planted a crop, and maintained five years of residence. Brushing aside Native American claims to large swaths of the Great Plains, this federal law pulled in homesteaders from the eastern United States as well as Europe. Towns with names like Glasgow, Havre, and Malta were named by the Great Northern Railway to entice residents from Scotland, Sweden, Norway, and other countries farther east to the promise of fertile land and pleasant climates. Other names were likely more utilitarian or locally accurate: Cut Bank, Shelby, Wolf Point, Poplar, Bainville.

Formerly just known as Rail Siding Number 54, Malta was named by a Great Northern official in 1890 when a post office was established. The land around Malta and south to the Missouri River (currently known as Phillips County) was settled later than other parts of the Hi-Line, even those farther west toward the mountains, because it was not suitable for farming wheat as had been promised by the government and railroad pamphlets. In addition to the poor soils, short growing seasons, and brutal winters, families soon found that 160 acres was not enough even for raising livestock. In response, Congress began increasing homestead allotments to 320 and then 640 acres. By 1916 came inevitable drought that pushed many homesteaders to leave or sell off their titles to other families.

Driving any direction out from Malta you see the bones of old homesteads: dirt-floored, crumpled-over log cabins on otherwise open patches of prairie. They are signs of a more active and populated past on the Hi-Line compared to the current sparse matrix of much larger ranches or federal lands. For the fortunate or determined neighbors who were able to consolidate their land holdings, the Taylor Grazing Act of 1934 boosted cattle ranching by opening federal lands to grazing by privately owned cattle. The land had reached a somewhat stable equilibrium with man—forcing livestock raising instead of wheat farming on the people. Families had to rethink the hundred-acre farms from their homelands and live at thousand-acre scales. For survival, acceptance of this isolation by distance had to be resolute and passed down bloodlines, because individuals might come and go, but families, property lines, and federal grazing leases had to stay intact. This way of life has persisted with few changes over the past eighty years.

• • •

The first time you meet Randy Matchett is likely to be on a dirt road or prairie field camp in remote central Montana just south of the Hi-Line. He is easy to spot in his white oversized pickup truck packed full of tools like a Swiss Army knife. He always carries with him chains and fence posts to tug himself or others out of the mud, a full mechanic’s chest of tools to fix any type of engine (from airplane to generator) on the fly, enough medical gear to serve as a veterinary lab, a rifle to sample coyotes for canine distemper virus, and a sleeping bag and pillow in the back seat to serve as his mobile home. These are tools of the trade for the lead wildlife biologist responsible for the million-acre Charles M. Russell National Wildlife Refuge. When he steps out of his truck, the first things you would notice are his felt cowboy hat and neatly trimmed, horseshoe-shaped dark mustache around a wry smile. He wears a government-issue uniform of brown denim pants and a button-up beige shirt with the U.S. Fish and Wildlife Service insignia of a flying goose on his shoulder. As he moves his wiry frame you will notice a slight arch in his back and limp that he attributes to a high school “rodeo” accident.

FIGURE 3. Short-horned lizard (Phrynosoma hernandesi) on the mixed-grass prairie of central Montana.

FIGURE 4. Old homestead in southern Phillips County, Montana.

I first met Randy in 1998 at the University of Montana when he gave a guest lecture on black-footed ferrets. He talked to a group of wildlife biology students about how he had spent the past four years trying to restore some of the Sybille captive stock into central Montana. I was enthralled by his story, but like most University of Montana students, I dreamed of studying the larger mammals—wolves, grizzly bears, or moose—in the mountains. I jotted down his email on the corner of a page in my spiral notebook, and did not think about him again until a few months later when I was graduating and without a job. Lost in the pile of applicants who wanted to work in the mountains, Randy put me in touch with a graduate student who paid me to do a summer job of trapping prairie dogs in central Montana. We translocated hundreds of prairie dogs onto Randy’s refuge to restore populations, and when that three-month job ended and Randy saw that I was still interested in the prairies, he offered to keep me on—a sort of on-the-job screening process that led him to offer me free housing and wages of $16 a day to help monitor his small population of captive-reared black-footed ferrets. I left my small car at the end of the pavement where the government truck Randy had left for me waited, and drove the sixty miles on dirt roads to a field camp he termed “Ferret Camp” that consisted of a handful of small camper trailers parked on an isolated tip of land along the Missouri River.

I was hired to follow the nightly movements of the small group of ferrets Randy was carefully trying to rear in the wild. He trusted his precious animals to me and a fellow drifter, Pete, an out-of-work high school teacher from Kansas. The goal was to keep track of how many of the handful of new wild-born litters would survive, and try to predict how many ferrets Randy might expect to see the following spring. The survival of a large number of kits meant that the Montana habitat was good. Also, the more ferrets that survived, the better Randy’s chances in getting more ferrets for release from Sybille stock the following spring. Like all field biologists, we shifted our lives to that of our study animals: sleeping days and working nights; eating one large meal a day; learning the feeling of a drop in barometric pressure ahead of a storm; judging the time of night by the height and phase of the moon.

We followed the kits every night into the fall, naming each one and tracking its movements between prairie dog burrows. We were collecting points on a map to create a sketch of each ferret’s life history for Randy. We rationed our food to be able to persist on a trip to town for food every two weeks and kept up our nonstop routine until the first week in November, when freezing water lines and winter started forcing us out of the camper trailers and back to the hardtop life of highways and electricity.

Pete left camp first, ahead of the north winds of the first severe cold front. Days shortened and nights grew so cold that I had to bring my truck battery into the trailer to be sure to have enough spark to start the old Dodge the next night. Like a failed homesteader, I felt the forces of weather and solitude pressuring me to leave Montana, yet I had no job to move on to. I dreaded the sharp cut of work that is field biology, from a life of continuous motion to sudden inaction when the fieldwork ends, money runs out, or the animals move on—a separation that was all the more paralyzing because we were working on such a rare and fragile animal, not knowing whether they would make it through the next five months of winter. Whether they would be here when I returned.

By mid-November a call came through on the old camp phone that was stacked on a piece of plywood in the corner of the barn. Grabbing my hat and gloves, I rushed outside and felt ice crystals instantly form in my nostrils. The chill of the cold plastic phone on my bare ear made me recoil, forcing me to hold the phone at a safe distance. On the other end of the line, the voice of a woman from the federal government repeated my name. She seemed pleased to have tracked me down in response to the application I filed the previous year to join Peace Corps. She offered a two-year contract as a biologist in the Philippines, a free plane ticket to a country I barely knew existed. I traced my mental globe to somewhere in Southeast Asia, the Pacific, somewhere warm—I did not hesitate.

• • •

In 2002, following my two years of international service and building a life as a tropical biologist, I found myself back in central Montana. Randy offered me a full-time job to help him again with black-footed ferrets, and I accepted before even getting off the plane back into the United States. He wanted me to move up to a little waterfowl refuge on the Hi-Line of northern Montana and work full-time to help him breed and rear black-footed ferrets in Montana so that they could be released there. It was a permanent job with pay, something scripted and directed, yet we knew that the outcome for the species was still far from certain—extinction loomed.

I arrived in the small town of Malta during spring, a time of hope and activity—hope that the ephemeral prairie rains would come and last into July before the grasslands dried out and returned to their more familiar and less nutritious brown. It was a time of preparation ahead of the busy summer months when ranchers must push cows out into summer pastures, fatten calves, and harvest hay before the long winter. But in Malta I was not a homeowner, not a landowner, not even a renter, more of a squatter. I was a twenty-five-year-old wildlife biologist living in a retired FEMA trailer left over from the latest Gulf of Mexico hurricane disaster that was government surplused and then hidden behind a maintenance building on the seldom-visited Bowdoin National Wildlife Refuge—a pinprick of a refuge on the larger map of federally protected areas barely large enough to justify having a full-time staff. I often imagined the poor family who had lived in the trailer before me. I created an image of a family from Alabama or Mississippi who had lost everything, cramming four kids and a grandmother into one of many white, tightly packed, federally purchased trailers in an abandoned soccer field on the Gulf Coast, each filled with a traumatized family under the government’s care. Based on the stains on the sofa and smell of the curtains, I thought that my trailer’s family must have had to stay in the encampment for months before they could find a modular house to rent with federal disaster aid checks, likely settling in a town far from the memories of the coast and where they had few relatives.

For me, the trailer was temporary living turned semi-permanent by cinder blocks under axles and power from an extension cord. The eyesore was hidden from public view by a ring of invasive, pale, stunted, and thorny Russian olive trees—few native tree species could tolerate the winter cold, summer heat, poor soil, and infrequent rain. As I cooked dinner on the cramped two-burner camper stove with borrowed pots and pans, I was given time to think, to reflect on how quickly my life became focused on a similar trailer three hundred feet away where dozens of beady eyes of baby black-footed ferret kits were still hidden from light by sealed eyelids. My list of chores for the next day accumulated in the back of my mind: clean nest boxes, weigh kits, disinfect floors, order implant tags, clean hamster colony, order new water bottles, mow preconditioning pens, feed ferrets, defrost tomorrow’s food.

In the evenings, memories of saltwater ocean and love came forward only when I finished my third bottle of beer. My thoughts and emotions of loss were likely not so different from the homesteaders from Europe who arrived in Malta more than one hundred years prior to me. Like them, the promise of the open plains drew me. I had headed west at the first chance for teenage independence to work summers on a Wyoming cattle ranch with my uncle. Spent four years at the University of Montana being trained as a wildlife biologist, and then traveled around the world once again to end up in the plains of central Montana.

Yet upon returning to Montana, the critical satisfaction I had found in its open spaces was gone. I had first met J after four months of living with hunters in the Philippine jungle. While I was digging with a pickaxe to build a hiking trail, she arrived at the wildlife sanctuary, blonde and confident on the back of a British United Nations volunteer’s motorcycle. She left with the British volunteer but came back a week later, tracked me down, enticed me to leave my post on occasion and travel the island, and made me fall in love. We had a tropical island love as only two biologists can, measuring the jungle trees, mapping the extent of coral reefs, surveying fish in the weekend market; reporting on components of natural beauty and living in thatch huts, hers on the coast, mine in the interior jungle. A life of continual motion in a corner of the world, without family so that we grew reliant on each other, yet knew there was an expiration date on our temporary lives when the two-year contract ended, a make-or-break deadline we avoided until the end, when she was first to leave. Yet nothing ended, and when forced to make a decision on the future, we made promises of finding each other back in the United States like high school sweethearts going away to college.

After dinner I went outside to smoke my next-to-last Philippine cigarette, knowing I needed to not be an addict and hoping to leave nicotine and the longings of my past in one symbolic, sweeping gesture of my body and mind. Outside the screen door of my Malta camper, I couldn’t focus on J or the tropics. I couldn’t confuse myself with the persistent question of why I chose to move to Montana, Randy, and black-footed ferrets rather than follow her to the East Coast. The mosquitoes were kept from my nose and mouth by the smoke, but they swarmed my ears, hair, arms, and legs. The mosquitoes of the Hi-Line were worse than those of any tropical forest or swamp. They swarmed on this temperate plain with the spring pulse of water to the point where you inhaled two or three with each breath. They turned the backs of white shirts grey, and then spotted with red where you had slapped one midmeal. I learned to walk fast, from door to door, car to building, home to office, to avoid the growing hemoglobin-seeking cloud from catching up to me as they honed in on my carbon signature. I finished only half the cigarette and retreated into my trailer, spending the next five minutes killing any individuals that followed me inside.

• • •

After the crash of the last wild ferret population in Meeteetse in March 1987, a captive population totaling eighteen ferrets was established at the Wyoming Game and Fish Department’s Sybille Canyon Wildlife Research facility. This included the critical late addition on March 1, 1987, of Scarface from Meeteetse, a particularly virile male who helped breed nine of the eleven females. Of the nine bred females, only two produced litters in the spring of 1987, eventually resulting in seven surviving young. It was a surprising success compared to the experiences at Patuxent a decade earlier.

In 1988, thirteen of the fourteen females produced litters, resulting in thirty-four young. There was high hope for the captive breeding program because minimum production numbers seemed to be met. It was at least a small buffer from extinction. Within a few years, the number of ferrets in captivity increased enough to allow the captive population to be subdivided. Individuals were shipped to the National Zoological Park in Front Royal, Virginia, and Henry Doorly Zoo in Omaha, Nebraska, dividing the population and limiting the risk that a disease outbreak or other catastrophic event at one site would cause extinction of the species. Eventually, ferrets were also housed and bred at zoos in Phoenix, Toronto, Louisville, and Colorado Springs.

Captive breeding was so successful that by 1991, ferrets were beginning to be released into the wild. Demand by states quickly exceeded supply, so a movement began to start small-scale captive breeding programs at the state level for those states that wanted ferrets. Captive breeding buildings and preconditioning pens were built in Colorado, Montana, New Mexico, and Arizona. By 2002, when Randy brought me back to the Hi-Line, the newly created Montana ferret facility had a couple of years of experience under its belt. Randy had already hand-picked as his captive breeding team leader Valerie Kopsco, a thin, energetic biologist from New Jersey with a soft spot for cowboys. The previous year, she had already tested the specially designed outdoor pens and indoor cages with a few trial ferrets. I was brought on as a second hand ahead of the big push to finally breed ferrets successfully and raise young kits in Montana.

We followed the husbandry protocol developed by the ferret recovery program on the basis of its success with the last eighteen individuals from Meeteetse. A sort of how-to guide for ferret keeping, this protocol had evolved over time with guidance from the Wyoming Game and Fish Department, the Captive Breeding Specialist Group of the IUCN (International Union for Conservation of Nature), and the American Zoo and Aquarium Association, and with hands-on expertise of many devoted biologists over the years at Sybille Canyon, Wyoming. By 1996, the U.S. Fish and Wildlife Service had assumed responsibility for captive breeding from the Wyoming Game and Fish Department, and the person to contact about any captive breeding question was Paul Marinari. Paul would be the first to deny the label of “Mr. Ferret,” placing credit with the teams and individuals that preceded him, but he more than any other person oversaw the quick acceleration in ferret-breeding success, and developed a smooth and effective operation that produced an annual flow of 150–200 kits.

When I first met Paul in 2002, he was single and lived alone in Sybille Canyon with the ferrets while the technicians that worked with him commuted the two-hour round trip up from Laramie each day. Upon first shaking his hand, I noticed that he had the sharp personality and watchful eye needed to ensure the conditions and care for such a sensitive animal. Originally from Philadelphia, Paul completed his master of science degree from the University of Wyoming by studying ferret behavior in South Dakota and evaluating the detectability of ferrets via night spotlighting surveys. Like a field biologist, to succeed at his job of overseeing captive breeding of black-footed ferrets, Paul dedicated and set the rhythms of his life to ferrets. He lived in a small home on the captive breeding site because caring for ferrets in captivity was not a 9-to-5 job. It required continuous attention and ability to respond to emergencies at all hours of the day and night. Ferrets had to be monitored and fed, and their cages had to be cleaned daily throughout the year. In springtime, monitoring of females was required to determine when they were in estrus to pair them with mates. Then, forty-five days later, they had to be monitored for births and the status of litters. In the summer, there was a need for monitoring and caretaking of vulnerable kits and their mothers. Then, in late summer and fall, kits were preconditioned and transported for release on reintroduction sites from Mexico to northern Montana. After the kits were shipped out to sites by October or November, planning for next year commenced as pedigrees were assessed and potential mate pairings were mapped out for February and March of the coming year based on a formula that aimed to maintain the greatest possible genetic diversity of the captive population. There was little time for vacation, and even less time for a personal life.

• • •

To rear the rarest mammal in the world required specially designed equipment. In Malta we built plywood nest boxes to Paul’s specifications for female birthing. A nest box was a small, sturdy, two-chambered box with a four-inch entry door from the top that could be locked with a latch. At the bottom of the box, a hole was drilled and four-inch-diameter black corrugated tubing was tightly connected that led to a larger plywood box with a Plexiglas front and screen top to resemble above ground exposure. All boxes were kept sterile and painted bright white. Outside, sixteen adjacent pens, each thirty-two feet long by thirty-two feet wide, were erected directly into and onto the prairie. Prairie dogs captured on local cattle ranches were brought in by the hundreds, quarantined, killed, gutted, organized into individual plastic bags, and frozen for a year’s worth of ferret food. Valerie had already established a colony of more than one hundred hamsters housed in metal bins in a nearby garage bay that would be used to feed young kits and train them to kill live animals. This was a gentle introduction to predation, as the small puffball hamsters were less likely to hurt young naïve kits than would the larger prairie dogs with strong jaws and razor-sharp teeth.

The delicate cycle of captive breeding began in earnest in March, when we became novice reproductive physiologists. Pairing normally solitary male and female ferrets together for extended periods of time can be dangerous. Long canines and muscles built for taking down prey nearly twice their size when used on each other can result in severe injury or even death. Thus, we carefully monitored the precise timing of when individual females entered estrus, using pipettes of water and microscope slides to perform vaginal washes. Counts of more than 90 percent of cells being keratinized indicated that a female should be ready to be bred successfully. We then placed a sexually active male with the female in an outdoor nest box for three days, hoping they didn’t instantly fight and listening for a struggle in the plywood box as we shut the door.

Following a pairing, we rested the male for three days prior to pairing him again with another estrus female—allowing his seed to restock. We similarly let the female rest, conducting an additional vaginal wash seven days after the initial pairing to determine whether ovulation had occurred. Given that all black-footed ferrets give birth around six weeks post-conception, using this initial pairing date we were able to fix the time when the females were likely to give birth or whelp.

Using this recipe, by June 2002 we produced eight litters totaling thirty-four kits. Thirty-four pinky-finger-sized young with their eyes closed wiggled in a pile of thin fur and pink skin. We left them alone in their indoor whelping boxes with lids closed tight. Just as we were nervous in pairing males and females, we were nervous of the mother rejecting or killing her young. To avoid tipping them into an infanticidal killing frenzy, we kept disturbance to a minimum; at first we opened a nest box lid only to change the bedding every five days. Despite this sensitivity, by July we had lost three kits. Two of the kits, when found, had been largely cannibalized by their mother. Was it a natural death of the kit and the mother simply ate the available carrion, an instinct to take what she could get to continue producing milk for the others? Or was it confusion by the mother, and infanticide as we had feared? Elsewhere in the animal kingdom the non-nurturing urge to kill off another mother’s kits to limit competition is fairly common. In this strange captive setting, did she not realize the kits were her own? Whatever the reason, with so few litters to raise, we hoped it was an isolated event. In another nest box, where one kit appeared to have died from an airway blocked by eating a small square of cardboard bedding material, we blamed ourselves.

• • •

By August, when the kits were well along toward feeding for themselves, Valerie and I began to alternate weekends off and I visited my parents, who had recently relocated for work at the newly created U.S. Geological Survey Northern Rocky Mountain Science Center in Bozeman. My father and I took my mother out to dinner for her birthday. Bad Thai food at a strip mall still tasted good because it was the first restaurant meal I had in a long time. I was at home, but I still felt restless without the ferrets to care for. They had become my crutch, my reason for leaving J, the only justification for a life away from a woman who loved me. I needed something, anything to give me a home, a peace of mind that reaffirmed that I was living a useful life and that I was not just passing through a cycle of travel trailers and temporary jobs. I needed something to give me traction when all idle thoughts seemed to slide toward loneliness. In an act of desperation, I went to the dog pound and adopted a red heeler, named her Abby, bought a sack of dog food, and headed back north to the Hi-Line.

FIGURE 5. Prairie dogs captured in live traps for transport.

When I got back to Malta on a Sunday evening, Valerie had left me a message that an entire litter of six kits died over the weekend. I wondered how, why, and if somehow I was to blame for taking two days off. We shipped the bodies down to the Wyoming State Veterinary Lab in Laramie, uncertain of what went wrong and anxious for the results. We worried that other litters could similarly collapse, so we once again cleaned the cages and disinfected the building, only with a new vigor. In the end, however, we could only leave the mothers to rest and care for their young.

Resigned to the will of the ferret mothers, we knew we could not disturb them with more attention, so we buried ourselves in the work of trapping prairie dogs for ferret food north of Malta. Saving the landowner the time and money of poisoning prairie dogs, in a single week we collected 516 individuals and placed them in elevated cages in an old tin shed with a concrete floor for a two-week quarantine. That was the set period of time during which a disease such as sylvatic plague would have run its course, and if they survived we could reasonably declare them disease-free ferret food.

While the prairie dogs were in quarantine, we spent the following weeks preparing the outdoor pens for ferrets. We checked for breaks in the first or second level of our fences that kept the ferrets in and predators out, and measured the voltage and cleared grass away from the electric fence wires strung to keep raccoons, skunks, badgers, and any other ground predators from climbing into our compound. Within each pen, we blew smoke from smoke bombs down into burrow systems with a leaf blower to check for escape burrows and filled in any breaches with gravel or concrete. We trimmed the grass down to the ground to resemble the closely cropped vegetation of a wild prairie dog town in the dry, clear days of midsummer. Last, we scrubbed out underground nest boxes that we hoped ferrets would use to spend the daylight hours and thus allow us to easily trap them for checkups. The nest boxes also made it easier for us to clean out their feces to prevent bacteria buildup and infections and to remove the accumulation of prairie dog fragments that attracted blow flies. These small flies were the bane of animal caretakers because on any scratch or wound they would lay eggs that would turn into flesh-eating maggots that burrowed just under the skin of our little brood of multi-thousand-dollar animals.

Once the prairie dogs passed quarantine, we selected a lucky few to pretend again to be wild and free. We released two or three into each cleaned-out pen to excavate the old burrow systems, performing prison labor outdoors after two weeks in a suspended square metal cage. Previously, the only boundaries for these animals were social divides between families on flat prairie. A lifetime of only imagined boundaries was replaced by real boundaries and confinement with strangers. I watched the selected few prairie dogs quickly readjust to the view of the sky, taste of fresh grass, and feel of dirt between teeth and toes. I silently urged them to enjoy their time in this semi-captive state, perhaps even escape, wishing I could relate to them that they had only a few days before they were to be recaptured and soon after butchered and put to use as ferret food along with the rest of their captive cohort.

While the captive prairie dogs were declining toward a feeble state on a diet of dried grain and alfalfa pellets, the ferret kits were getting feisty and outgrowing their indoor plywood boxes. Despite their size, which nearly equaled their mothers’ so that the nest box was crammed with writhing bodies, we stuck with Paul’s strategy of keeping families intact and indoors until fifty or sixty days after birth. We defrosted prairie dogs from our line of large chest freezers, quartered their bodies, and fed the torsos to the females and kits that devoured the tender, marble-sized dark red organs inside. I left the tougher hind legs for adult males that sat alone in their pens, useless until the next breeding season.