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Bringing Back the Bighorn, by Lynn Bama
  
by Lynne Bama
 

The cliff is covered with patches of slick snow. Icicles sprout from a crack in the rock just below the outcrop where a bighorn ram is standing. His coat is a plushy taupe, shading darker on the belly and legs, white on the muzzle and rump. His horns curl three-quarters of the way around a circle, and show that his prime of life is near.

Now the band of ewes he is courting appears, their small bright faces materializing out of crevices and crannies like a find-the-hidden-sheep puzzle coming to life. The animals move with deliberate grace on the treacherous surfaces, picking their way delicately along ledges, or moving vertically in great, heart-stopping bounds. The ram, which carries the additional weight of his substantial horns, is as heavily muscled as a prize fighter.

That they are here at all is a minor miracle, for these animals are the survivors of a North American wildlife disaster.

Rocky Mountain bighorn ram. Photo courtesy of Bighorn Institute.In July 1835, while in the mountains southeast of the present Yellowstone National Park, trapper Osborne Russell wrote, "An eye could scarcely be cast in any direction around, above or below without seeing the fat sheep gazing at us with anxious curiosity or lazily feeding among the rocks and scrubby pines."

One-hundred fifty years ago such herds could be found, not only in rugged mountain areas, but on badlands and river bluffs in the Northern Plains and canyon walls in eastern Oregon and the Southwest. But the most alpine-and probably most abundant-of the region's six subspecies was this one, the Rocky Mountain bighorn. It ranged along the cordillera from northern New Mexico to the Canadian border.

By the second half of the 19th century, populations of native sheep were dropping all over the West. Some of the carnage was due to unregulated hunting, but a lot of bighorns simply fell sick and died. By the 1940s, U.S. herds had plummeted by 99 percent. The Audubon bighorn, which had lived in river breaks and badlands as far east as the Dakotas, was extinct; the Rocky Mountain subspecies was hanging on only in the most remote and inaccessible mountains.

Today, long after better hunting laws and wildlife management techniques have brought other big game animals back, wild sheep still seem fragile-unable to reclaim the territories they have lost, suffering from ailments carried by their tame relatives. While the species has made a modest recovery in the past 50 years, we still do not fully understand its needs, and the changing character of the West itself now further imperils these charismatic animals.

Despite their recent troubles, wild sheep are one of the planet's great success stories. Equipped with industrial-strength digestive systems that can handle wind-battered, dusty alpine plants, and an amazing ability to negotiate rough terrain, they came into their own in the Pleistocene period of the last million years. During melt-offs of the great ice sheets, these glacier followers spread from their original home south of the Himalayas all around the northern hemisphere.

In 1961, Valerius Geist, a Canadian graduate student in zoology, headed for the high country of British Columbia to study wild sheep. He quickly realized why their relatives in western Asia, which began living with people over 8,000 years ago, had been one of the first animals to be domesticated. The bighorns he studied soon became so tame-and fascinated by his camera-that he was forced to climb a tree whenever he wanted to change film. Once a band even followed him home, and had to be led back where they belonged.

"I had the head of one sheep (peeking) underneath one arm, and the head of a ewe under another ... it was just a bloody nuisance," he says.

Domestication was, according to Geist, a disaster which turned sheep into "sad, tragic caricatures of their former selves. The process did more than transform their coats into year-round winter wool; it turned them into 'virtual cripples' that had to be protected from their natural enemies, shrank their brains, and even ruined their flavor."

By enfolding it into the dense complex of people and livestock that soon formed in Asia and Europe, domestication also turned the sheep into a walking warehouse of diseases. Members of the multispecies Eurasian community traded pathogens and parasites back and forth like baseball cards, creating ailments-and immunities to them-never before seen on Earth.

Meanwhile, the wild sheep that had migrated into western North America were still immunological innocents. When the two species met at last, disaster was inevitable.

Biologist Valerius Geist studying bighorn in Banff, Canada, 1964.  Photo by R. Geist, courtesy HCN.Wild sheep instantly recognized the domestic flocks as their relatives, and were understandably curious about them. Although large flocks with herders and dogs frightened them off, there were always strays to investigate; and domestic ewes in estrus were irresistible to bighorn rams. Just as whole communities of native peoples here succumbed to Eurasian diseases carried by explorers and settlers, so the American sheep were decimated as soon as their tame relatives arrived on the scene.

The link between domestic sheep and bighorn disease is like the one between cigarettes and lung cancer-logical, statistically obvious, and extremely difficult to prove.

Pioneer historians were quick to notice that bighorn epidemics regularly followed the arrival of tame woollies. The collapse of wild sheep populations all across the West was first blamed on scabies carried by domestic flocks.

In the 1970s, however, research revealed that the scabies mite carried by bighorns could not live on its tame relatives.

"For 50 years we were blamed for all the scabies epidemics," Tom McDonnell, associate director of natural resources at the American Sheep Industry Association in Englewood, Colo., says indignantly.

These days, biologists are targeting Pasteurella, a bacterial pneumonia carried by many hoofed animals. Few biologists doubt that some strains common in domestic sheep are lethal to bighorns, but what actually happens during a bighorn epidemic is still far from clear.

Dale Reed takes notes about bighorns near Fort Collins, Colorado. Photo by D. Reed, courtesy HCN.Last winter, David Hunter of the Caine Veterinary Teaching and Research Center in Caldwell, Idaho, got a rare chance to study such an event in progress, when 72 sick bighorns from a herd in Hells Canyon of the Snake River were brought to the Caine Center. The outbreak, which appears to have begun with a domestic goat, eventually killed all but eight of the sheep he studied. But according to Hunter, the organisms which that animal carried were only involved at the beginning of the die-off.

Hunter says that not only did the sick sheep carry 13 different strains of Pasteurella-most of them not uncommon in wildlife-but the animals also had viruses, lungworms, scabies mites, internal parasites, fleas, and ticks. "You name it, we found it," he says.

Once a trigger mechanism sets the process of a die-off in motion, he adds, common organisms become massive killers. And, like the pneumonia the AIDS patient finally succumbs to, "Pasteurella tends to be the final nail in the coffin."

"It's hard when the biologists call me and say 'What do we do'" Hunter says. "There are a lot of people who love these animals, and they're frustrated with us because we don't have simple answers."

The uncertainties that cloud bighorn epidemics have made it possible for the sheep industry to sidestep the issue of its impact on the wild species for years. And, since stock growers control so much wildlife habitat in the West, game agencies have been reluctant to connect bighorn disease outbreaks with domestic herds unless the evidence is airtight.

"It may damn well be true," a Colorado wildlife official comments, "but you can't just say that."

The evidence may be only circumstantial, but the numbers are compelling. Writer Ernest Thompson Seton estimated that there were once as many as two million bighorns in North America. Their numbers started crashing as soon as domestic herds arrived. By 1910, there were nearly 30 million of their tame relatives on Western ranges, and bighorns were still losing ground. In the mid-1940s, however, the changing economics of wool growing pushed the domestic herds into a long decline. Today, they are less than a tenth of what they once were.

Meanwhile, just as the sheep industry started to shrink, North America's bighorn herds, which had bottomed out at around 14,000 in the 1940s, began to recover.

The waning political clout of wool-growers may have emboldened them, but many state wildlife biologists now say openly that domestic sheep and bighorns don't mix. And even moderates like Tom Thorne, longtime supervisor of the Wyoming Game and Fish Department's Wildlife Veterinary Services branch, admit that buffer zones between the two species make sense.

Now that the great tide of domestic woollies has receded, it would appear that re-establishing native sheep in the West would be an easy matter. But putting bighorns back where they used to be is not so simple.

Running down from the northern border of Wyoming is a range of mountains the natives called the Bighorns because of the abundance of wild sheep there. The animals they were named for vanished decades ago, and in a state famous for its wildlife, the empty promise of the Bighorn Mountains has long been something of an embarrassment.

A bighorn release in Wyoming. Photo by D. Huber, courtesy Wyoming Game and Fish Department.Until Geist began his Canadian studies, no one understood why native sheep never found their way back to the Bighorns. He discovered that while bighorns may wander great distances under natural conditions, they are generally moving between places they know. He theorized that during the glacial periods when sheep were spreading around the world, every melt-off of the ice exposed huge areas of grassland ready to be occupied, continuous habitat that sheep could spread through freely. But under recent climatic conditions, tree-lines climbed the mountain slopes, and the animals-which generally dislike entering timber-were restricted to now-isolated open patches. They survived by passing the knowledge of such usable spots from generation to generation.

Young wild sheep are not great explorers. They are hero-worshippers that follow the impressive older animals about, in the process learning the locations of the seasonal grazing areas they use. "It's a primitive form of culture," Geist says, "a living tradition."

When the animals' near-annihilation at the end of the 19th century left parts of their former habitat vacant, however, those very traditions made it impossible for the animals to reinhabit them. "Sheep as a species have no meaningful response to this new situation," Geist wrote.

The first effort to bring wild sheep back to the Bighorns took place in 1934, when the Sheridan Sportsmen's Club released 20 animals from another Wyoming herd there. (According to one version of the story, their pelts were found the following spring near a poacher's cabin.)

Between 1959 and 1994, there were 13 more releases of wild sheep there. Most of the animals have disappeared, and only recently have wildlife biologists begun to understand why. Most herds were too small; it was not until 1990 that a Nevada wildlife biologist discovered that herds of fewer than 50 bighorns invariably disappeared within 50 years.

Another problem was habitat. In the beginning, game managers simply put bighorns back into the places where they had existed in the old days. Whether those areas could still support wild sheep was seldom investigated. It was not only that domestic animals were eating the plants bighorns had once used. After decades of fire suppression, shrubs and trees were growing ever thicker, blocking migration routes and forcing bighorns to stay closer to their cliff refuges.

Says Kevin Hurley, a Wyoming Game and Fish Department wildlife biologist who is also executive director of the Northern Wild Sheep and Goat Council (an organization of sheep managers and specialists), "A lot of sheep have been poured down a hole because the proper evaluations weren't done beforehand."

The most recent effort to bring native sheep back to the Bighorns took place in the early 1990s at Wyoming's Shell Canyon. Determined to avoid mistakes, biologists measured the forage, set fires to increase grass and open paths to the high country, and released, over a two-year period, more than 100 animals.

Shell Canyon is traversed by a main route to Yellowstone National Park and is a perfect showplace for a transplant. A recently erected sign at the Shell Falls visitor center announces, "Bighorn sheep once again roam the mountain range that was named after them."

The legitimacy of that claim is fading fast. When asked how many sheep are left in the herd, local Wyoming Game and Fish biologist Tom Easterly says, "I'd like to think 30 to 50, and that's optimistic."

What happened to the Shell Canyon sheep is not clear, although biologists have several theories. One is that, since more than three-quarters of the transplanted animals came from a herd that had recently suffered a pneumonia epidemic, they may not have been in good health to begin with. Another theory is the bighorn's old nemesis, the domestic sheep.

"You have to devise some sort of Berlin Wall between domestic and wild sheep," bighorn authority Geist says. In the case of Shell Canyon, the wall was probably not high enough. Although no domestic sheep use the canyon itself, there is a grazing allotment with 1,400 of them just beyond its south rim. From what biologists can gather, some of the bighorns found their way to them. "We flat underestimated where those transplanted sheep would go," Hurley says.

And if wildlife biologists' suspicions are correct, the future for bighorns in these mountains does not look bright-over 28,000 domestic sheep graze there each summer. The best habitat for bighorns, unfortunately, sometimes is also the last best wool growing country.

Shell Canyon may be a worst-case scenario, but it illustrates a number of the problems wildlife biologists encounter when managing bighorns. Transplants, especially when they have to be repeated again and again, are expensive.

The actual capture, which involves luring the animals under a net with apple pulp and alfalfa, then dropping the net on them before handling each sheep individually, costs $180 to $200 a head. Add to that radio collars, aircraft time, veterinary services, laboratory analyses, and so on, and the investment per animal rises into the thousands. In Wyoming, where all the money for wildlife management comes from license fees, bighorns don't bring in enough to cover such costs.

Where does the money come from? From hunters like Jerry Fletcher, an Arizona man who paid $310,000 for a Montana sheep license in 1994. He didn't find the ram he wanted that year, and returned in 1995 to spend another $281,000. The second time around, he got his trophy. "He is worth every day and every dollar," he commented.

There is big money in bighorns. In 1996, Wyoming (which may have more Rocky Mountain bighorns than any other state) had over 7,500 resident applicants for its 199 available bighorn sheep licenses. A nonresident license in that state now costs $1,500.

Add to that the $6,000 to $10,000 cost of a guided hunt, and that trophy on the den wall becomes a sizable investment. It is also the centerpiece of a small industry of outfitters, taxidermists and manufacturers of outdoor equipment and weapons.

There are a number of hunter organizations dedicated to wild sheep, and in the past 19 years, they have generated at least $20 million for bighorn programs in the United States, Mexico and Canada.

Most of that amount was raised by the Foundation for North American Wild Sheep (FNAWS), a hunter organization based in Cody, Wyo., which funds programs ranging from land acquisition and transplants to advancement of sportsmen's rights, and has an almost mystical attitude toward bighorns.

The friendly wild sheep Geist encountered lived in an area protected from hunting. But the same rams that nibble on a biologist's camera and eat salt from his hands become supremely elusive after they have encountered rifles. And the terrain they take refuge in-often well over 9,000 feet high-is the most rugged country in the West.

"You have to be in good shape," says Karen Werbelow, executive director of FNAWS. "You spend days glassing. For those that are successful, it's a moment that cannot be expressed."

Although policies are now beginning to change somewhat, most states have traditionally focused their sheep harvests on the trophy ram. Werbelow does not feel this practice has a bad effect on the species. "Big rams are past their reproductive years," she says.

But Steven Buskirk, head of the Department of Zoology and Physiology at the University of Wyoming, says trophy hunting exerts "a pernicious kind of selection" on bighorns. "There's no great virtue in removal of the most robust animals," he says.

Rodney Honeycutt, a conservation geneticist at Texas A&M University, concurs. Any time people apply any kind of selection, he comments, the frequency of a trait can be altered. As for the way harvest strategies have historically been set, he says, "Very little real biology goes into that."

Aside from genetics, there can be other worrisome effects of an obsession with trophies. The largest wintering concentration of bighorn sheep in the U.S. is found at Whiskey Basin, at the northern end of Wyoming's Wind River Mountains. This indigenous herd had for decades been steadily growing and overusing parts of its winter range in spite of land acquisitions and range improvements. Since there was no demand for the excess ewes, managers tried to keep the population in balance by transplanting surplus animals elsewhere. Between 1949 and 1995, nearly 2,000 bighorns were shipped out of this area to new spots in Wyoming and the West.

But in the late 1980s, according to Tom Ryder, the Wyoming Game and Fish Department biologist who was managing the herd at the time, the number of bighorns was underestimated. In late 1990, after a two-week cold period with wind-chill factors of more than 100 degrees below zero, and at the height of the rut and hunting season, the Whiskey Basin sheep started dying. By the time the episode ended, between a quarter and a third of the herd of 1,500 to 1,600 had succumbed.

What had caused it? There were no domestic sheep in the area. "We pretty much decided it was a stress-induced pneumonia," Ryder says. And the stress was at least partially the result of overcrowding and poor nutrition.

The final effect of trophy hunting on Whiskey Basin has been disastrous. In the five years since the pneumonia outbreak, not enough lambs have survived to keep the herd from shrinking. "That's the sad part of this whole deal, and what has us more concerned than anything," Ryder says. Trapping has stopped, and hunting licenses have been cut drastically. As a transplant source, he adds, "It's gone."

With the demise of Whiskey Basin as a source of sheep to take elsewhere in the West, FNAWS's emphasis is now shifting to Hells Canyon of the Snake River, in the process raising some questions about the wisdom of having a hunters' organization at the center of wild sheep management.

Rocky Mountain bighorn ram. Photo courtesy of the National Bighorn Sheep Interpretive Center.Hells Canyon, which lies between Idaho and the states of Oregon and Washington, was once home to numerous bighorns. By the 1940s, however, they had vanished.

In the 1970s, the three states around the canyon began reintroducing wild sheep to this former range, part of which was designated a National Recreation Area in 1976. At the time, the link between domestic sheep and disease in bighorns was not fully understood, and the first group was put onto a sheep-grazing allotment. The bighorns died out immediately.

Until 1995 the transplants continued-and so did the die-offs. The final one reduced the canyon's population of 600 wild sheep by over a third.

It was not until a coalition composed of local hunting and environmental organizations and the Nez Perce tribe filed suit against the U.S. Forest Service, which manages the National Recreation Area, that the situation began to change. The suit challenged U.S. Forest Service authorization of domestic sheep-grazing there.

FNAWS was not a party to the lawsuit, and in fact initially sided with the wool growers, demonstrating that they are no more anxious to confront the livestock industry than state game agencies have generally been-and for similar reasons. Ranchers control too much access to game for hunting organizations to antagonize them.

"They fall for the ranchers' line," says Mary O'Brien, ecosystem policy analyst for the Hells Canyon Preservation Council.

As a result of the controversy, sheep allotments in Hells Canyon have now been drastically reduced, and FNAWS, in what the group calls "the greatest privately funded wildlife project of this century," has pledged to raise $10 million over the next 10 to 20 years to put enough bighorns back in the canyon to serve as a nucleus for future transplants.

Hells Canyon appears to be a place where hunters and environmentalists could work together toward the common goal of bringing the area's wild sheep back. But that hasn't happened yet. Part of the problem may be cultural.

To the businessmen and outfitters who dominate FNAWS, environmentalists in general seem like extremist tree-huggers better at hatching court cases than doing anything "constructive" for animals. "What projects have they funded for wildlife?" asks Werbelow.

O'Brien, on the other hand, says that a lot of FNAWS members are too naive to realize the importance of maintaining habitat for wild sheep, "so they don't just throw money around." While she is glad to have them at Hells Canyon-"it's exciting for the animals, for people's spirits"-she asks, "Are they going to let biology come first?"

Meanwhile, the local groups and tribe whose court action has made the Hells Canyon bighorn project possible are not part of the interagency management team FNAWS joined. The reason is money.

But what questions of public policy are raised when a private organization contributes so many millions to the upkeep of a species? Will the bighorns released in Hells Canyon over the next few decades have strings attached-strings held by the hunters who have bought and paid for them?

Rocky Mountain bighorn sheep range - in 1997 and historically. Graphic courtesy HCN.Rocky Mountain bighorns are not an endangered species. Now almost 25,000 strong in the United States, they have been reintroduced into all the states they once ranged. But although many people are enthusiastic about transplant programs, the question remains: Do the programs help?

Transplants appear to have succeeded in several states, especially where they are far from domestic flocks, but in Wyoming and Colorado, which together account for almost half of all the Rocky Mountain bighorns in the West, the picture is not bright.

According to a 1990 study done for the Colorado Division of Wildlife, only two of 25 Colorado transplants have produced herds of over 100 animals. Almost half either failed or have fewer than 50.

In Wyoming, over two-thirds of the areas seeded with wild sheep between 1949 and 1994 are now empty, or have fewer than 50 animals left. Only three transplants here have produced healthy populations.

Reintroductions often multiply encouragingly for the first few years, only to crash and then stabilize at much lower levels. Few such herds ever learn to make the characteristic seasonal migrations. Typically relocated onto winter range, they refuse to travel through the timber that lies between them and the summer grass of the high country.

Geist has long thought that wildlife managers should use a different method to reintroduce bighorns to their former ranges. Since mountain sheep learn from their elders where to go at various times of the year and are so easily tamed, he thinks biologists should raise lambs on the bottle, then guide them.

"You stitch together a halfway decent habitat, and then you walk your mountain sheep through this country," he says.

Although he first suggested this technique over 20 years ago, no one has tried it yet. "This is not a macho-type thing, with net guns going off, and men wrestling panic-stricken sheep," he comments.

The fate of many transplants remains obscure, in part because the hunters who so readily put up the cash for them are not so generous when it comes to following newly released bighorns around to see how they fare. Some biologists feel that FNAWS is too addicted to media-friendly projects like releases and water tanks, and needs a more coherent research strategy. But few of them dare to say so openly, for when it comes to wild sheep, FNAWS holds the purse strings.

If there are any heroes in this story, they come from the ranks of these field biologists, modestly paid and often overworked people, who seem genuinely dedicated to bighorns. While trying to improve the management of wild sheep, they must tiptoe carefully around the interests of both ranchers and hunters. And lately, many of them are watching changes in the Western landscape with dismay.

Jack Hogg, a wildlife ecologist who studies bighorns for the Craighead Wildlife Wildlands Research Institute in Missoula, Mont., worries that wild sheep are losing their winter habitat to subdivisions and other development. "Science is telling us we need large landscapes, not just little samples," he says.

Mike Welch, big-game coordinator for the Utah Division of Wildlife Resources, says that historic bighorn habitat along the Wasatch Front, which went downhill when livestock grazing converted it from grass to shrubs, is now coming back. But when wild sheep come down onto the winter ranges these days, they encounter people-suburbs and "backyard sheep." "Is there a future for bighorn sheep here?" he says. "Probably not."

Tom Lytle, recently retired from the Colorado Division of Wildlife, reports that bighorns in that state are being so harassed by year-round recreational use of the mountains that they have taken to hiding in the woods.

It is hard for most people to realize that a wild sheep that looks outwardly calm may be a bundle of anxieties inside. Even mild alarm raises a bighorn's energy expenditure, and it can take as much as 72 hours for the physiological effects of stress to dissipate. Since chronic stress depresses its immune system, a sheep that sees a backpacker, a photographer, or an ice climber as seldom as once in three days may be at risk for disease.

O'Brien observes, "It appears that it is really hard to be a bighorn in today's world.... We need to give all kinds of room to them."

Whether these remarkable animals will get such room remains to be seen. It would be a sad irony if the Rocky Mountain bighorn, which symbolizes the remotest, most inaccessible mountain wildernesses in the West, survived 100 years of adversity, only to fall victim to the current American love affair with its home.

  

Lynne Bama is an essayist, journalist, poet, and dedicated gardener who lives in Wapiti, Wyoming.  Her work has appeared in Sierra and Orion, and she has recently published in two anthologies: Ring of Fire and Thunder of the Mustangs.

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Resources.
 
 

Bighorn Institute

National Bighorn Sheep Interpretive Center

Foundation for North American Wild Sheep

Rocky Mountain Bighorn Society

Craighead Environmental Research Institutute

Hells Canyon Preservation Council

Bighorn Sheep in Rocky Mountain National Parks, National Biological Service, U.S. Geological Survey

Restoration of Bighorn Sheep in Metapopulations In and Around National Parks: Conservation of a Severely Fragmented Species, National Park Service
 

 
     
    
  
 
   
    
  
 
   

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