A Sustainable Future for America's Great Plains
By Ernest Callenbach
Chapter One: The Bison Heartland
For more than ten centuries the bison, elk, deer, and pronghorn played in grasslands that covered what we now label as a dozen states, over which they ranged freely as forage and browse and water sources drew them. They were kept from overrunning their foods resources by two major kinds of predator, human hunters and disease organisms, though wolves and bears had some effect too. The sun-powered productivity of the continent's sea of grass was shared with millions of prairie dogs, with ferrels and badgers and hawks that preyed on the prairie dogs, and with billions of tiny decomposers that consumed dead organic material and sent it on its next life cycle. Thick, rich soils were held in place against the fierce Plains winds and the scouring Plains rainstorms by a deep, tough network of perennial roots; thus, erosion was minimized and streams ran clear. The bounty of the landscape immeasurable and eternal, with bison as it dominant feature.
Bison are quintessentially American animals, noble symbols of wildness, freedom, and self-sufficiency. In their heyday, when 30 to 60 million bison roamed North America, they were the most numerous grazing animals on earth, far surpassing even the great American wildebest hends.
The largest and most powerful animals on the continent, bison have a special claim on our attention. They are intimately tied to the history of America, as well as to the ecology of our grasslands. And, as we shall see, hey have a place in our future as well.
The breathtaking splendor of the bison herds of three hundred years ago was almost indescribable to the first European observers. Today, when our cattle stand meekly behind fences and bawl for their dinner, those thundering wild herds are beyond our imagining. Then, bison were a standard part of the American landscape across half the continent, as omnipresent as cars as today. The random bounty they represented was incalculable, like that of falling fruit from tropical trees--they were simply there, part of the endless plenty offered by the original garden of the continent.
In several prehistoric forms, bison had endured in North America for hundreds of thousands of years. Indeed, it may well have been in pursuing bison that hunters first crossed the Bering land bridge and populated the Western Hemisphere. During the long centuries of Native American occupation of the continent, bison provided the Plains dwellers with food, shelter, clothing, fuel, and artifacts. Later, during settlements of the Midwest and Plains, bison furnished the Euro-American immigrants with food, warm robes and coats, and clean-burning dung chips for their cooking fires--an essential in largely treeless regions. Although later whites showed little compunction about wiping out the bison, America could not have become what it is if bison had not provided a living bridge across the Plains.
The first Spaniards who spotted bison understandably called them racas, cows. But bison only superficially resemble cattle. For one thing, bison are surprisingly agile and fast: they can spin instantly on front or rear legs and can outrun the fastest horse over a five-mile chase. Bison are magnificent, muscular beasts: bulls weigh as much as a ton; cows, more than half that. Their stampedes literally make the earth tremble. They are eye-catching in their unique humped profile and shaggy coats; resourceful in finding grass, whether in dry seasons or in the teeth of blizzards; cooperative and resolute against predators.
As early observers learned, bison are wary of humans. People sometimes tame newborn bison calves, but not for long. Today's wild bison, such as those on the National Bison Range in Montana, can be herded by expert riders into enclosures for annual culling and vaccination, though a few recalcitrant bulls always elude the herders. Once driven into the corrals and chutes, many bison get hurt trying to kick or butt their way out even through 4-inch-thick timbers. The implicit motto of the bison rings with a determination we remember well from out history; Live Free or Die!
Their dominance of the American landscape rested on the fact that bison were perfectly adapted to life on the enormous grasslands of the continent. Bison are ruminants, with multipart stomachs that maintain a resident population of microbes to ferment chewed grass and render it capable of absorption. A typical bison day, whether over the long centuries or now, begins with a predawn grazing period, followed by the alternating periods of regurgitating and chewing their cud and more grazing. This process enables bison to digest cellulose, the principal solid component of plants, and explains why they could be so numerous over such an extensive range.
A basic bison group numbers twenty to fifty animals; the endless herds described in frontier tales gathered only during migration. It was once believed that bison migrated seasonally over long distances from north to south and back, but it is now thought that their migrations covered only a few hundred miles and were generally directed toward better grazing land or water. Bison also move around because of weather, as has been observed in Yellowstone National Park and historically; fierce blizzards drive them toward rougher or timbered country, where they can shelter from the wind and snow. A bison group will sometimes cross long stretches of dry country. Bison tend to visit water at least once a day, though they can, if necessary, go several days without water--far longer than cattle can. Movement over the land is led by mature females, who are widely thought to be more intelligent than males and have an excellent memory for seasonal and spatial patters of grass availability and locations of water sources. Nobody now alive has seen a really large migrating bison herd, but historical accounts describe, with perhaps some exaggeration, herds stretching as far as the eye can see, estimated to be as much as hundred miles in length.
For bison, grazing involves movement while eating, over distances ranging from a quarter mile to three miles, followed by a brief resting period--not the relatively stationary grazing of cattle. Grazing bison may appear from a distance to be moving slowly, but they often travel at a good walking pace for a human. Due to their different anatomical structure, the gait of bison is not exactly like that of cattle.
In the wild, bison live for an average of twelve to fifteen years, through some individuals may live to forty. They are fearsome in defending themselves against predators. Predators, of course, are essential to every healthy ecosystem as regulators of population balances. Since the 1930s, scientists have known that predator control harms rather than helps bison and other large wild species, for steady predation is necessary to weed out weaker animals and thus keep the herd as a whole strong. In Canada, wolves have been observed hunting bison successfully--though they prefer to go after the relatively solitary moose--but careful observation in Yellowstone has revealed that severe winter weather kills far more bison than do predators of any kind. Native American hunters also played a crucial role as predators on bison before the European period. Their hunting impacts did not become ecologically unbalancing until whites brought them firearms and provided markets for hides and tongues.
The condition of a bison's fur varies from the deep, thick, warm coat of late fail and winter through the ragged-looking coat of spring and summer when the heavy for is being shed in patches. Because bison eyes are set farther out on the sides of the head than those of cattle, they have practically 360-degree vision. They can detect very distant movements that are almost imperceptible to humans. However, at closer ranges they rely more on their excellent senses of smell and hearing. Like other social animals, they remain acutely aware of the locations and dispositions of nearby herd-mates, on whom their welfare and sometimes their safety depend--but who in return demand unceasing attention to dominance-submission relationships.
Whether on the move of loafing around, a bison herd is surprisingly noisy. Groups of cows and their calves, either newly born or yearlings, tend to stick fairly close together and engages in steady interchanges through reassuring grunts--not the mooing many people expert. Attention is secured and deference demanded through a variety of sounds ranging from snorts to growls, often accompanied by attitude-adjustment butting. Occasionally bison will utter a sonorous snort that bears some resemblance to sounds made by their distant mammalian relatives, humpback whales. Bulls have a wide repertoire of threatening noises, from an early-warning low rumble with extended, whitish tongue to terrifying bellows and roars, which become so loud in the mating season that they can be heard as much as three miles away.
Like other animals, including humans, bison also signal their intentions by body postures. They maintain firm and stable dominance orders, among females as well as males; moreover, a dominant cow can intimidate a subdominant bull. Rank-indicating gestures with head and horns are very common, especially among the top animals. The bison tail is also very expressive. As Milo J. Schult and Arnold O. Haugen, experienced observers of contemporary bison under all imaginable conditions, put it:
An observer can get some idea of a buffalo's state of mind by looking at the position of the tail. When undisturbed, the buffalo's tail hangs down or flicks back and forth occasionally to get rid of a pesky fly. When mildly excited, the tail is raised somewhat; the greater the degree of excitement, the higher and more rigid the tail posture. Such excitement is frequently accompanied by defecation. Finally, when fully aroused and combative, the tail is held in a rigid, upright position. It is at this time that the observer should be most wary.
The fly-whisk function is important; like other large grazers, bison are bothered by a variety of flies.
Considering their size and weight, bison are remarkably light on their hooves. They can scramble slopes quickly, and its is frequently said that they can jump over a six-foot fence from a standing start. They can scratch their shoulders or face by delicately bringing a rear foot forward. They enjoy licking and grooming themselves and other bison. And they love to frolic; young animals especially often simply run about aimlessly, mock-mating, play-fighting, and even play-stampeding.
For most of the year, bulls live on the fringes of groups of cows and calves. Individual bulls may wander deep into woodsy canyons, enjoying patches of grass too small to interest the whole herd. Only during the rutting season, in midsummer, do bulls mingle with the cows. The bison mating season is a time of much bellowing, challenging, threatening, and head-to-head butting contests between dominant bulls. Bison skulls are remarkably thick in the forehead area, which is covered with a heavy pad of fur, and the horns are curved in such a way that frontal butting does not usually involve goring. A fight normally ends with the weaker bull backing away and trotting off. Here nature seems to be aiming for genetic sorting but not death; a few dominant bulls, who intimidate all the others, mate with the cows. Only in captivity, where one bull can get cornered, do fatal fights seem to be common.
A bull who has just been dominated by another bull seems to "work off his frustration" by roaring, pawing the ground or even goring it, and wallowing--lying down and rolling back and forth vigorously, often in a dusty depression that is also used for insect-control wallowing. A dominant bull patiently "tends" a cow in whom he is interested, staying close behind or alongside her for many hours, or sometimes even several days if necessary. During this time he fends off the approaches of other bulls, occasionally rests his chin on her rump, does a certain amount of stuffing and licking, and waits until she is ready to be mounted. In this process, he smirks at her in a stylized, neck-extended grimace called the lip curl, the precise function of which nobody--except, presumably, the bison themselves--really knows.
Most calves are born in late April to mid-May following a nine-and-a-half-month gestation period. Whereas the coats of adult bison are varying shades of dark brown, the calves are bright orange-rust and remain so for about three months. Initially, they have no humps. They weigh between thirty and seventy pounds at birth and are extremely winsome. A bison cow is ferociously protective and allows nothing and nobody to get between herself and her calf.
Our Lost Companions
Among the Indians, bison and many other animals were treated in stories and in life as beings who spoke, felt, and thought much as humans do. They were an equal part of the universe, deserving of careful attention, respect, and love; they were spoken of in the same terms as were family or clan members. And animals were to be seen everywhere--close outside the villages or camps, just over the hills, coming down to drink at the streams. (Bison wore deep trails leading to riverbanks.) Not a day passed without important interactions between humans and other species. This constant contact is hand for moderns to imagine. For most of us, animals are merely an industrial resource. Cattle and poultry are produced out of our daily sight, and we consume them in processed forms that are carefully rendered unrecognizable; to acknowledge that our steaks or drumsticks come from fellow beings would be too painful.
We are distantly aware of wild creatures inhabiting landscapes we seldom visit--parks and wilderness areas, where deer and bears and eagles may occasionally be seen--but those creatures do not qualify as part of our "real," everyday lives. We count ourselves lucky to experience them through nature programs on television.
Thus we modern human beings live in a landscape that is, by the standards of our long history as species on earth, deprived of our large animal companions. Yet evolved to what we are in close conjunction with these animals, over millions of years. On some deep level we must miss them, for they gave human world spiritual meaning as well as sustenance. when we came to dominate them almost completely, and subsequently wiped many of them off the planet, we lost essential evolutionary partners, and we are the lonelier for it. Their absence is our loss, psychologically,spiritually, and morally, and it is felt by many besides Indians and poets. If you go to a zoo--a melancholy in the eyes of many--and watch the human animals there, especially the children, you may see in their eyes some recognition of our fundamental comradeship with wild animals.
There are people, and I am one of them, who believe that the natural landscape with its full range of inhabitants can be restored in protected areas. There we can bring in meaningful numbers the great carnivores who evolved with humans as the top predators in North America: grizzly bears, wolves, mountain lions. Though the devoted efforts of conservation biologists and their allies we may yet manage to preserve large enough wild areas to guarantee the survival of small remnants of these magnificent species--likes us, predators who occupy the tops of complex food chains.
But in realistic terms, the bison is the only large wild animal with whom there is any prospect of sustained coexistence on mass terms.. (With bison would naturally come smaller numbers of the other species that share grasslands habitats with them, chiefly pronghorn, elk, mountain sheep, and deer.) Bison do not fear humans, and a modest level of human activity does not make an area uninhabitable for bison, as even very limited road-building, mining, or timber cutting do for bears. We can therefore, share land with bison in a way we could not with other large animals. The possibility of our coexisting with bison opens up some novel and exciting prospects for conservation biology (the new field which applies biological science to species preservation), for land management, and for ranching It also challenge us, as well will see later, to imagine new relations between ourselves and wild nature.
In about a quarter of what is now the contiguous United States, bison prevailed as the most numerous, the most impressive, and also the most useful members of the animal kingdom. We will not see huge migrating herds, but it is reasonable to predict that in fifty or a hundred years, a mere moment in the bison species lifetime, there will be millions of these mighty lords of grass again. A large ecological detour will have been completed, and one part of the United States, at least, we will have been restored to a naturally sustainable state.
Land, Rivers, and Climate "In the long run, land determines."
--Wes Jackson paraphrasing John Wesley Powell
Bison once ranged a much larger territory that the Great Plains, which many still think of as bison's sole ancestral home. All the tallgrass prairies just to the east, with better soil and more rain, were bison territory too, and the richer forage of this region must have supported the densest herds. (The general quality and particularly the protein content of grass depends directly on rains, especially springs rains.) But bison also inhabited areas where forests were dominant, since they can browse on leaves as well as graze on grass. There were bison as far east as the Appalachians, where I grew up; perhaps of some deep folk memory, my hometown baseball team in central in Pennsylvania was called the Boalsburg Bisons. When English settlers first arrived in Georgia, they encountered "innumerable" bison. There were bison in Mexico, in Texas, and on up through Canada to the Yukon. There were bison in the Rockies, as there still are--in Yellowstone National Park; at the National Bison Range in Moiese, Montana; in Grand Teton National Park; and on the Flying D Ranchin in Montana, owned by media magnate Ted Turner. However, they never spread in significant numbers through the dry and inhospitable Great Basin into the lusher country along the West Coast.
Nowadays, you can find small, thriving ranched herds of bison everywhere in the country. But their heartland remains the Great Plains, and that is where we are likely to see, in coming decades, the greatest resurgence of bison herds. There land is cheap; most of it is unrewarding for family. But it was home to the bison, and it will be again. The Plains are high, dry, gently rolling country, and until white occupation they were entirely covered with mixed native grasses, including the grama grasses which were the main sustenance for the bison. Originally the Plains were treeless except for cottonwoods and willows along the streams. In some sections, like the Sand Hills of Nebraska, the predominant impression of the region as you move through it is rather like being at sea; you think that once you crest the next rise you will gain a view of a broad vista and get your bearings, but in reality all you see from the rise is a new series of rises. In the absence of mountains or other massive landmarks, early white arrivals, like the Indians before them, relied on the rivers for orientation; without them, they would have needed to use compass and sextant, like seaborne navigators.
It is easy to confuse the Plains with the neighboring prairies to the east. The two domains do not divide sharply along some some boundary line; nor is their topography uniformly different. They are defined by rainfall and soil types, both of which have local variations. In a general way, we could say that the prairies extend through the great, mostly flat central valley that occupies the middle of the country to the edge of the eastern woodlands, which in historical times covered much of the country east of the Mississippi River. Westward, the prairies extend at least through the first tier of states west of the Mississippi and give way to the drier, sparser Plains in the Dakotas, Nebraska, Kansas, Oklahoma, and Texas. From there, the Plains run to the Rockies, and within the Rockies there are basins that have a predominantly Plains character. On both Plains and prairies, local differences in landforms, stream patterns, soil and vegetation, and temperature made life easier or more difficult for bison. But throughout this vast area, bison roamed free, occupying what ecologies call their riche--their special place in the great panorama of life.
The Soil and Under the Soil
To people who thinks that grass is just grass, the Plains and the prairies offer an unknown new universe. Short (six to twelve inches tail) buffalo grass, hairy grama, and blue grama grow on the driest, short-grass Plains. On the rainier eastern prairies, Indian grass, big bluestem, and switchgrass reach heights of six to twelve feet. The mixed prairie in between has western] wheatgrass. little bluestem, and sideoats grama. All these grasses intermix in some extent, depending local conditions of soil and moisture, so there is no rigid division of grass types. An undisturbed grassland is a thing if underappreciated beauty. As Lynn Jacobs write,
Prairie grassland usually contains an average of 125-150 plant species and numerous animal species. Here one finds many different grasses and flowering plants. Perennial forbs [nonwoody but nongrass plants] are widespread, especially members of the sunflower and legume families. Annuals typically comprise less than 5 percent of plant species. Thick stands of bushes and trees commonly line drainages.... While generally less biotically diverse than the bunchgrass community, prairie grassland usually has many more individuals and as much greater biomass per unit of area.... Indeed, grassland generally has the deepest, most fertile and productive soil, highest erosion resistance and water retention, and greatest biomass of animals of all the major bioregions.
Plains and prairie soil, like soil everywhere on the planet except in the driest deserts, is home to countless small organisms whose total subsurface mass is much greater, for any given natural area, than that of the most visibly imposing large mammals is aboveground. Studies carried out on the prairies have counted nematodes, which are small roundworms with teeth, and found that they number a half million per square foot, they consume more of the region's basic biological productivity than do the cows or bison that tramp over them. (Subsoil life thrives better, research shows, when the grasses are grazed.) But even these amazing numbers are dwarfed by the numbers of microorganisms more than 2.5 billion bacteria; 400,000 fungi; 50,000 algae; and 30,000 protozoa. It is these microscopic beings that convert nitrogen, phosphorus, and sulfur in the soil into forms that higher plants such as grasses can utilize. Thus, without these microorganisms there could be no plants, no bison, and no humans. Moreover, they decompose organic matter such as dead grass leaves and stems and animal droppings, releasing carbon dioxide and water into the soil and leaving a residue of fine particles that we call humus, the buildup of which has, in fact, created the deep prairie soils. Thus, in a full biological perspective, life under the soil surface is more critical, complex, and massive than is the life visible to us. This is particularly true of Palins and prairie native grasses, which have larger parts underground than aboveground.
Once the bed of an inland sea, the Plains owe their basic slope and elevation to sediments washed down from the Rocky Mountains. Their nearest counterparts is the Russian steppes. Rainfall is skimpy an erratic, averaging around 20 inches or less per year in recent years it has averaged 13 inches in northwestern Montana, 16 inches in west-central 19 inches in Oklahoma. But multiyear droughts are the norm, and attempts to plow the land, which was originally protected by a thick cover of remarkably deep-rooted, dense grasses, have sooner or later led many farmers to disaster. The soil itself is fertile, and wheat is still a major crop, along with a drought-resistant songhum called milo; indeed, the Plains still produce most of America's wheat exports. But plow agriculture using annual monoscrops like wheat and corn leaves the soil between plants unprotected and is a permanent invitation to erosion.
Throughout the world, erosion by wind and water has been dangerous depleting overgrazed grasslands, causing desertification and lower productivity for human purposes. In America, just as in less-developed countries, we "mine" soil by letting it washed downstream to the oceans. This erosion process is far advance everywhere in the country, including the deep-topsoil area of the Midwest. It is also severe on the dry, winblown Plains grasslands. Even in those extensive. Plains areas that have hardly been plowed, where most of the grasslands are used for cattle raising, degradation due to overgrazing is depleting the land. As we will see, bison are part of the solution to erosion problems.
Bison and Grassland Ecology
"Grazing large herds of bison in large pastures represents a cost-efficient method of cropping native vegetation, maintaining a functional ecosystem, providing local employment in an industry that is indefinitely sustainable, and providing a healthier meat."
-- Craig J. Knowles, wildlife consultant
It is the working theory of The Nature Conservancy's preserves in Nebraska and its just-opened preserve in Oklahoma that bison grazing, together with the effects of occasional fires, will tend to bring back native grasses and lead to a stable ecosystem. The process has also been the subject of research at Custer State Park in South Dakota, at the Konza Preserve of Kansas State University, and elsewhere. In recent years, small, museum-like preserves of native grasses, harbingers of more extensive future restoration, have been established through the persistent efforts of volunteers. The most remarkable of these preserve "islands" is within the giant circle formed by the nuclear accelerator at the Argonne National Laboratory outside Chicago. Another lush example is found on the grounds of the Kauffman Museum in Newton, Kansas. These precious areas nurture an incredible richness of species compared with the desolation to which most Plains and prairie grassland has been reduced. One writer noted their "scintillating interdependence that constitutes a single living a whole."
Devoted souls who care about bringing back the native grasses can be found everywhere. In Chicago, they have banded together in a loose organization called the Wild Onion Alliance. ("Chicago" comes from the Indian name for a wild onion, and the city and its surrounding have a surprising number of vacant spaces suitable for restoration.) Such people set a powerful example and issue effective appeals for physical labor and vigilance from a large force of concerned citizens. Each community, they say, must develop its own "prairie consciousness" in order to push back the concrete, the alien bluegrass lawns, and the cornfields. After ten years of hard work, they have brought back a forest preserve north of Chicago to its ancient state of viability through persistent seeding amid existing vegetation, a method they have found to work better than plowing and planting anew.
There are now such fragments of restored prairie in many states--too small to support bison, but inspiring examples of what can be done. Unfortunately, the extraordinarily labor- and money-intensive work that has gone into these experimental and educational plots is too expensive and demanding to be applied on a regional scale. But The Nature Conservancy hopes that the cropping of grasses by bison, who tend to bite off the top parts of grass rather than tear away the near-ground growing shoots as do cattle and sheep, may aid the recovery of native grass species that cannot survive under livestock.
Native grasses are adapted to occasional heavy grazing, and many grasses actually grow more vigorously when grazed. A free, nomadic bison herd might graze a given grass area one year but not return to it for several years. The constant pressure of fenced and maximum-stock grazing, however, has tended to favor grasses of European origin.
The effects of fire were also undoubtedly crucial to maintenance of the original grasslands. Some fires were induced by lightning and others were set by Indians. Periodic fires, though many researchers like to classify them as disturbances, clean out dead grass materials that do not decay rapidly in dry climates and return them as ash to the soil nutrient cycle. They also create ecological mosaics--spotty patterns where different plant species offer different habitats to different animal inhabitants. Fire stimulates the germination of certain seeds. It is well documented that after a fire, a new round of more productive growth begins, offering new, protein- and energy-rich shoots that please grazers. Fire may even help to prevent outbreaks of pests and plant diseases.
Scientists like Al Steuter, who is in charge of the bison at The Nature Conservancy's Niobrara Valley Preserve in Nebraska, have worked out the sequence of what they call patch dynamics. An area that bison have been lightly grazing accumulates more dead grass and is thus prone to fire. After a fire, helped by increased penetration of sunlight and warmer soil temperatures, a new round of growth begins; bison may be particularly attracted to burned areas for two or three years. Gradually, however, they turn their attention elsewhere, and dead grass begins to build up again, setting the stage for the next fire.
Indians certainly employed fire, and it seems likely to Al Steuter that their influence altered the grasslands to favor species that could support a wider range of grazing intensives. Without fire, he says, woody plants tend to take over grasslands. Steuter points out that since most lightning-induced fires occur in the growing season, when grass is greener, they are naturally less fierce than dormant-season fires and produce a characteristically small burn patch. Ninety percent of lightning-caused storms in the West burn out or are rained out before reaching an acre in size. The human-set fire regime at the Niobrara Preserve tries to replicate the impacts of Indian- and lightning-set burns.
Bison's observant and great speed meant that they were seldom endangered by the relatively erratic and mostly small-scale fires of presettlement days. Fires are less perilous to fast, alert animals in open country than viewers of Bambi might expect. The fires at The Nature Conservancy preserves should thus be compatible with bison, especially when their free-range area is expanded and there is little possibility of their being trapped by fences.
In short, there is a remarkable match between bison and their ancestral grassland home. The hardiness that enabled bison to survive the severe climate of the Plains is especially impressive compared with cattle's vulnerability. Bison can even reduce their metabolic rate when exposed to intense cold and are much better than cattle at finding sheltered places to wait out storms. One bison ranger and researcher, even though he favors using cattle along with bison on small areas of public lands for ecological maintenance, says flatly, "Clearly, bison are relatively better suited to a continuous year-round presence on a northern mixed prairie natural area than are cattle."
Particularly in the tallgrass prairies east of 94 degrees west longitude (a north-south line passing just east of Kansas City), the abundance of vegetation is astounding, particularly the number and seasonal variety of brightly colored wildflowers. The Buffalo Gap National Grassland in South Dakota distributes guides to forty-six species of grasses that can be seen on its nearly 600,000 acres-from crested wheatgrass to buffalo grass to little bluestem to something known as stinkgrass--and displays dried samples of the major grasses in its visitor center. A similar list contains eighty-nine wildflowers: western yarrow, white prairie aster, cutleaf goldenweed, nipplewort, prairie coneflower, miner's candle, lambsquarter, and dozens more. Some of these plants are extraordinarily well adapted to a dry climate: Barr's milkvetch develops a root deep and strong enough to anchor and sustain it for forty to fifty years.
Bird and small mammal populations are extremely diverse on the Plain. Hawks and owls, turkeys, pheasants, flycatchers, flickers, and dozens of other birds are common in grassy areas, while a surprising variety of waterbirds (especially herons, geese, and cranes) frequent rivers and lakes. Crouse, once unbelievably common, are now rare.
The diversity of grasslands is particularly significant for bison. Polycultures, such as the mixed grasses and forbs that bison eat, turn out to be more productive than monocultures. In other words, an acre of mixed prairie grasses produces more biomass--food for humans or animals--than does an acre planted solely in corn or wheat. In a sense, this should hardly be surprising, since peoples in the Western Hemisphere have been planting beans and melons among their corn for thousands of years. But it is only recently that a trend in the social sciences, called rational peasant analysis, has dared to assume that indigenous people who have survived for millennia just may know what they're doing. Unfortunately, our style of development is almost always at their cost. We could surely have learned much about bison from the Plains tribes, but we killed off long ago the hunters who were the keepers of bison lore.
Bison's famous roaming, like that of other wild grazer's on the Plains and on the great grasslands of Africa and Asia, was not merely an inborn predisposition. Bison and other grazing animals become visibly stimulated, in ways we do not yet understand, on entering a new, rich pasture area, and, of course, roaming gave access to continually new forage. Roaming also helped minimize encounters with predators, who more easily concentrate on a sedentary herd, and moving in bends promoted ready self-defense against predators when they appeared. Roaming presumably was also a response to the eventual fouling of a grazed area by urine and dung.
Grazing by millions of bison and other species not only did not degrade the Plains and prairies by promoted coexistence and coevolution of animals and grasses in a remarkably rich and productive symbiotic relationship. The crucial role of the frequency of grazing, as opposed to overall intensity of grazing, went unrecognized during most of the history of the Plains. Received ideas about how many grazing animals can be supported by a plant community have nothing to do with wild species such as bison. This previous thinking derives from rainy European areas, where domestic animals were kept on the abundant grass of small, fenced pastures and a simple rule of thumb sufficed: do not overstock (that is, have too many animals for the total grass available). But an observant and thoughtful former Rhodesian game official named Allan Savory has recently extended our understanding of how wild and domestic animals interact with grasses in dry environments. The inventor of the term "short-rotation grazing," Savory has applied a systematic ecological analysis to the problems of ranching, and we will see later how his ideas are being put into practice by bison ranchers. But his thinking also bears on the history and future of wild species such as bison.
Savory's fundamental was to study closely what occurs at the soil's surface over time. Grass looks relatively healthy, he found, can still be in trouble if the plants are widely spaced and the soil in between is bare and hardened, offering no foothold to new young plants. Conversely, grass that looks severely nibbled down may actually be capable of good recovery if it is composed of numerous young, vigorous plants spread uniformly over the whole pasture. (Unlike leafy plants, grasses grow from the bottom; that is why mowing a lawn does not destroy it.)
Bison grazing in historical times was often intensive in local areas and its impacts were considerable, especially when combined with the bison's wallowing and trampling. However, herds would soon move on to other areas while an affected area recovered. Savory contends that such temporary, intense impacts are in fact essential, whether the grazers are bison or livestock, for they stir up soil and push seeds into the ground so they can germinate successfully.
Jack Norland, a researcher in range science at Montana State University, has concluded from his own work that "bison naturally exhibit short duration grazing behavior when grazing large pastures." Thus, if large enough pastures are available, building a lot of internal fencing and moving animals around among different pastures is unnecessary. Left to themselves, bison move constantly, not staying in any one place for more than a day. Both herds and individuals distribute themselves over all of an area, and bison come back to regraze areas at varying time intervals. Norland argues, "Just leaving the bison alone in an adequately large are (with suitable habitat) is the grazing system would be easiest, most efficient, and would offer the least chance of damaging the pasture. This would also probably be the most productive. Of course proper stocking rates [numbers of animals per acre] are needed for this to work."
We may see for ourselves that an unmanaged herd will prosper on ample acreage by observing the healthy bison in Yellowstone National Park--now about 4,000 animals and likely to grow to some 20,000 before the 2.2 million acre park becomes overpopulated. As we shall see, management of public lands for true multiple use, combined with expansion of bison herds on Indian reservations, could add many more millions of acres for bison. However, on the relatively small areas where bison ranchers have been operating, Savory's novel management strategies can substitute for natural grazing patterns. Yet even on public lands, some managers continue to follow traditional agricultural practices rather than learning to rely on simulating major ecological processes of fire, bison grazing, and natural plant succession.
Although Savory's general analysis of the grazing process and its relation to the health of grasslands is an important advance, his management recommendations are restricted to limited-acreage situations. For the future of bison, we must give priority to Norland's conclusion that bison grazing in large, unfenced areas provides ecologically satisfactory natural rotation. The ultimate bottom line is this large herds of bison can be sustainably (and profitably) kept on suitably large unfenced ranges on the Plains. As long as land remains divided into small parcels, the always precarious micromanagement of grazing impacts becomes necessary; yet cattle raising, burdened by the costs of internal fencing and intensive management, will continue to degrade the land and, if left without subsidies, to cause ranchers to go broke. Nature is giving us a signal that in our current land-division practices we have been thinking like real estate agents and that we must instead learn to "think like bison."
It appears that the only way to replicate the ecological symbiosis that free-roaming herds once had with grasslands is to put bison, elk, pronghorn, and deer back on large territories, along with their appropriate predators (including humans, hunting on a year-round basis), and let the reestablish coexistence with the grasses and the myriad other forms of life there. With bison and their companion grazers, it seems almost certain that the best management is no management. A few large ranches, following the Ted Turner operation's lead, will be able to implement this policy, but for the most part the task will fall to our public lands. Full implementation will probably require a century and will test to the utmost our temptation to imagine that, with our limited understanding, we can do things as well as nature.
Bison affect other features of grasslands besides grass, particularly streamside vegetation. A large herd of bison visiting a water hole or riverbank tramples it severely. In times past, however, when bison had access to unbounded expanses of land, their visits were intermittent, a fact that mitigated their impacts. Certainly bison do not display the predilection for sticking close to water that cattle have, perhaps because of their origins in wet southern Asia. Sharman Apt Russell says it well:
The effect of cattle on riparian areas is well documented. Unlike wild ungulates, cows tend to stay near water, to wallow in it, to lounge on the stream banks, and to trample the same ground over and over. As they lounge, they eat--grasses, tree shoots, whatever they find. On the John Day River, they eat, steadily, the willow and red-osier dogwood than act to slow the force of floods and protect the banks. They eat the grass that shields the soil from sun and wind, keeping soil temperatures low and reducing evaporation. They eat the sedges that are filtering out sediment, cleaning the water, and building up banks at the same time. When this kind of vegetation is overgrazed, the look of a stream changes drastically. Trees such as willow, aspen, alder, and cottonwood disappear as mature trees die out and the young shoots are consumed. In areas with deep alluvial soil, the stream begins to downcut, creating deep channels that result in a lowered water table.
Bison, on the other hand, tend to drink and then move on--far and fast. Bison do wallow, both in dry depressions to dust their coats and in wet depressions to cover themselves with a layer of mud for protection from insects. Nevertheless, they wallow mostly on high, level areas, and their wallowing produces bare, depressed areas that promote species diversity because they become tiny wetlands after rains.
Bison Digestion
Bison consume a greater range of plants than do the cattle that have replaced them. They respond flexibly to forage quality and abundance. Moreover, bison seem to digest what they eat more efficiently than cattle, perhaps because of different digestive-tract bacteria and protozoa; they can certainly achieve protein and energy intake equal or superior to those of cattle.
Bison ferment their cud more than cattle do, and perhaps for this reason, along with their superior nitrogen recycling, they have a higher digestive coefficient--that is, they get more out of the dry matter and fiber they eat. Actually, the nutritional needs of bison may be slightly different from those of cattle, although herd managers tend to treat them alike and rely on cattle rules of thumb in critical matters such as how many acres to allow for each bison. (On the high, dry Plains, a bison may need fifty acres.)
Bison diets tend toward grasses and sedges [grasslike plants with solid stems], though they will eat forbs and shrubs (like willow) if they have to. It intrigues scientists that bison can subsist on low-quality, high-fiber diets, whereas cattle require finer fare. In fact, bison digestions are rated between 3.7 percent and 6.1 percent more efficient than those of cattle. Nature has equipped them well for survival on the Plains.
Like other ruminants, bison emit large quantities of methane, a gas that is a major contributor to the greenhouse effect. In this meat-eating epoch, there are more than a billion cows aboard the planet, producing some 15 percent of the methane in the atmosphere. Methane is also produced in voluminous quantities by the flatulence of a human population explosion nearing 6 billion, by decay processes in rice paddies and swampland, and by the digestive processes of the planet's staggering population of termites. Thus, it seems likely that the bison population's methane output, whether that of the past or that of bison brought back to the Plains in the future, is not a significant factor in the global methane level.
Indians and Bison
Even before they had houses, Indians hunted bison successfully. On hands and knees, their human identity concealed with wolf skins, they stalked and killed individually bison with bows and arrows. They surrounded small groups of bison, confused them by shouting and waving, and finished some of them off with bows and arrows. Most dramatic of all, they drove whole herds off cliffs that the Sioux call pishkun and whites call buffalo jumps; people waiting at the bottom clubbed and butchered the fallen animals, leaving deep deposits of bones over the centuries.
Some Plains tribes who lived in settled villages along rivers, and practiced extensive gardening to produce much of their food--the Pawnee, Arikara, Mandan, and others--also hunted bison on semiannual hunting expeditions. However, in traditional tribal life, whether settled or nomadic, the bison provided for an impressive proportion of the people's needs. In fact, Plains Indian life would have been unthinkable without bison. Both Indian traditional stories and later white writings conjure up the thrill of the bison hunts; riders galloping bareback after the dangerous racing animals, shooting arrows faster than a gun could be reloaded. As whites later remarked, the bison was the Indians' general store. Shirts, leggings, dresses, belts, and moccasins came from the hides, as did tipi covers. Bison bladders made good water containers, and rope could be braided from rawhide strips. Spoons, ladles, and cups could be fashioned from horns, which were also important in headdresses.
Bison robes were a basic household resource, used for keeping warm, sleeping on, and sleeping under. Tanned hides were used for storytelling artwork. Knives, arrowheads, shields, and personal ornaments came from bone and hides; bones also made scrapers and hoes. Bowstrings and arrow wrapping came from sinews. Harnesses for horses and dogs, pouches for carrying things on horseback, lariats, snowshoes, sled runners, even covers for balls used in ball games--all came from the bison. So did ceremonial objects like masks, rattles, and winning sheets for the dead. (Even the rails found use--as fly whisks!)
Hump meat was considered a particular delicacy, along with tongue, brains, heart, and liver; dried and crumbled jerky pounded into a cake with berries and fat produced pemmican, a portable, preserved high-energy food. Bison were by no means, however, the sole item in tribal diets. Reading explorers' accounts gives the impression that Plains tribes ate nothing but bison meat, perhaps because the early mountain trappers and explorers themselves, lacking Indian knowledge of the region's plant resources, had to depend entirely on game. It is now recognized that so-called primitive peoples ordinarily enjoyed a much wider, richer, and healthier diet than humans now consume--dependent as we are on just three seed-bearing cultivated grasses (wheat, rice, and corn) for most of our caloric intake. Thus, it should not be surprising that Indians ate not only large amounts of bison but also quite a number of plants. During the winter, particularly, people without sources of carbohydrates could not have survived on bison meat alone because it is so low in fat. Indeed, the limits on Indian populations on the Plains may have been set by the amount of nonmeat foods available not by the supply of bison. It appears that tribal groups may have nomadically followed the development of prairie turnips (or Indians bread-fruit), succulent roots that they tracked more intently than they tracked the bison herds and dug up with sticks made of sharpened elk antlers. And buffalo-below plant flowered at rutting time, signaling people when it was time to head for the hunting grounds. Indians also ate the scarlet buffalo berry. Prairie chickens (pinnated grouse) were a tasty staple, as they were for the whites, who later examined them in many areas; they survive now only in rare places where traditional rotation of crops is still practiced. The grouse depended on seasonal grazing by bison to "open the grass," so they declined with the herds--a correlation that inspired a sad Indian lament, "O come back too, prairie chickens!" Surveying the fate of the species, William Least Heat-Moon reflected, "As goes the prairie chicken, so goes the prairie and its people."
Anlelope were another staple food over much of the Plains, as were elk in some places. Ian Frazier gives a much more exotic list of Indian foodstuffs, which included geese, ants, dogs, grasshoppers, beaver tails, wild peas, chokecherries, rose pods, wild plums, turtle eggs, wild artichokes, morning glory roots, wild onions, juneberries, and cottonwood bark. All in all, then, the diet of the original Plains inhabitants was rich, varied, and without question more healthful than the current American diet heavy in beef, salt, sugar, and fat.
The Balance Upset
The size of the herds that existed when whites first landed on the continent began to diminish early in the nineteenth century. A great drought struck the Plains in 1840, and another drought in 1867 supposedly starved millions of bison on the southern Plains. Diseases from introduced Euro-American livestock probably also contributed to some decline. Nonetheless, the bison-centered ecological balance that had prevailed on the Plains since the last ice age was not fatally disrupted until the arrival of whites. The first few trappers, explorers, and fur traders seemed to pose little threat. But after them came buffalo hunters, preying on the bison. Then came traders, making their living off the hunters and trappers and Indians. Then settlers took possession of the land to extract the accumulated richness of its soil, and gold miners invaded the Black Hills, Bandits, gunfighters, lawyers, and storekeepers arrived to live off the townsfolk and settlers. Finally, the military and its civilian helpers killed or rounded up the remaining Indians.
The water and land were at first exploited by open-range cattle barons and their hired guns, but then came "the plow that broke the Plains." Wave after wave of farmers built sod houses, plowed, planted, watched their crops shrivel or blow away, and went bust. So in time a new variety of predator appeared on the Plains: not carnivore, not even human, but nonetheless voracious. Banks gobbled up the farms, giant grain-trading corporation learned to manipulate commodity prices, producing waves of bankruptcies. Seed companies, fertilizer companies, and equipment companies racked up sales to failing farmers. These new predators were mostly legal fictions called corporations: self-replicating organisms driven by an ineluctable need to maximize profits, protected by law from personal liability claims. They steadily sucked money from the farmers, driving them to try ever harder to squeeze money from the land. For a time, the farmers fought back through populist political organizations. They even formed a new party and sent a few representatives to statehouses and to Washington, but their uprisings were soon beaten down.
As Ian Frazier sums up the situation in his book Great Plains:
This, finally, is the punch line of out two hundred years on the Great Plains: we trap out the beaver, subtract the Mandan, infect the Blackfeet and the Hidatsa and the Assiniboin, overdose the Arikara; call the land a desert and hurry across it to get to California and Oregon; suck up the buffalo, bones and all; kill off nations of elk and wolves and cranes and prairie chickens and prairie dogs; dig up the gold and rebury it in vaults someplace else; ruin the Sioux and Cheyenne and Arapaho and Crow and Kiowa and Comanche; kill Crazy Horse, kill Sitting Bull; harvest wave after wave of immigrants' dreams and send the wised-up dreamers on their vary; plow the topsoil until it blows to the ocean; ship out the wheat, ship out the cattle; dig up the earth itself and burn it in power plants and send the power down the line; dismiss the small farmers, empty the little towns; dry up the rivers and springs, deep-drill for irrigation water as the aquifer retreats....
The Bison Heritage
When historian Frederick Jackson Turner declared in 1893 that settlement from sea to shining sea had closed the American frontier, only a few hundred bison remained, almost all in vestigial herds maintained by a handful of preservationists. There were some in Texas, a few in Montana, some that poachers missed in Yellowstone, a few dozen in (remarkably) the Bronx Zoo. By the 1920s, most Americans believed that the bison had vanish entirely, along with the Indians--both remembered only by their presence on the nickel coin. Nonetheless, during the latter decades of the twentieth century a sustained recovery program, with both private and public support, has had great success. In 1995, there were some 200,000 of these impressive animals in the United States and Canada, and their number is growing rapidly. The species is no longer endangered. Bison are steadily gaining new friends among the public at large, among wildlife biologists, among conservation organization, among Indian tribes (including some with no historical connection to bison), even among politicians. The greatest of American animals is coming back.
But bison restoration on a significant scale will not be easy. Bison are wild, freedom-loving beasts. These weighty symbolic virtues also pose difficult problems--conceptual and practical, economic and political, cultural and ecological. Indeed, if we are to let bison be bison, we will have to modify some of our current ways of being human. These changes will benefit us as well as bison, but they will be profound.
No comments:
Post a Comment