Preparing for the Future:
Projecting Bison Herd Sizes, Market Potentials, and the Most Effective Management Pathways
by
Terence P. Yorks
High Level Research
Smithfield, Utah 84335, USA
and
Kathleen M. Capels
Utah State University
Logan, Utah
[Originally published as pages 384-395 in Irby, L. and Knight, J., eds., International symposium on bison ecology and management in North America. 1998. Bozeman: Montana State University.]The present set of images and text Copyright 2001 by Terence Yorks.
Abstract
The Ghost Dances of the 1880's anticipated the reappearance of bison in full measure. At that time, and to most people still, this possibility has seemed scientifically unlikely. However, a set of computer-model projections derived in 1984 have thus far been confirmed, which indicate that bison could return to their pre-Columbian numbers in as little as 30 more years if just the present herd expansion rate continues. Since the market for bison products should easily support this innate growth potential, both ranchers and marketers should be aware of this anticipated trend, along with the historical potentials and pitfalls of such a rapid expansion. If too much rugged individualism is retained, they could fall prey to the tragedies of localized overstocking and ecological collapse, to a parallel with the still recurring cattle cycle as in the U.S., or to the dilution of human health and ecosystem values by confining the animals' natural movement patterns.
Alternatively, ranchers can work together, and more fully utilize bison characteristics that maximize meat quality, land value, and overall economic return. Very large parcels of land are the effective management key, wherein the animals can retain essentially free movement for their selective foraging abilities. This also requires 1) the skillful adding back of balancing vegetation, grazing, and predator species, 2) minimal intrusion of heavy machinery and chemicals, and 3) final product brand-naming, including provable quality at all levels. These can be accomplished most effectively by cooperative ownership either by individual ranches banding together to eliminate fencing between them, by formal corporations (with updated requirements for responsibility), or by traditional co-ops in which all who work or invest have a direct, fair-share stake in the results.
The latter choice absolutely requires active cooperation among humans, throughout the growth, marketing, and processing pathways.
A Pivotal Perspective
To bison, a fence is like a government regulation to a human: if it makes common sense, it will be obeyed;if it seems otherwise, it will be ignored.
Background
One of the centerpieces of the environmental preservation movement has been our national success with the North American bison herd. Bison numbers had plummeted from as many as 70 million at the beginning to less than a thousand by the end of the nineteenth century. After being saved from looming extinction by the actions of a few courageous and farsighted individuals, recovery has progressed to include about 250,000 descendants of these noble animals roaming portions of their native habitat.
What this herd increase augers for the future could be an even more astonishing accomplishment. Ernest Callenbach (1996), in his highly readable speculation Bring Back the Buffalo, estimated that there could be 30 million bison by the year 2011. While more detailed predictive models indicate that his particular timing is unrealistic, it remains nevertheless highly possible that still within most of our lifetimes the North American bison herd could once again reach the size it was in the days before plows splintered the natural cover of the plains. Bison, fully restored, could bring with them the myriad species with whom they shared its open space. With them, too, could come dramatically diminished pollution, a greater net profit for landowners, and improved nutrition for humanity.
One basis for a better-substantiated conclusion regarding herd size is a previously unpublished computer model written ten years ago to predict bison numbers, whose results have closely paralleled what has happened since (thereby surprising even its author, Yorks). This proven-to-be-as-expected growth rate thereby creates a plausible extrapolation for the future.
Computer modeling of natural processes in general has been justly criticized for routinely missing elements of real-world complexity and uncertainty, and so failing to be accurate. The exception has been when approximation is incorporated within the models' programming, for then the outcome can point out trends worth watching carefully, as in the increasing global climatic instability which has been loosely labeled as global warming. The value of such projections increases as their initial results are confirmed over time.
Our particular bison extrapolation affirms that the exponential growth principle which many see as frightening for human numbers contains a more positive potential for other species, within a more natural context for all of us. If its predictions continue to hold true, one consequence will be a triumphant culmination for a key pioneering environmental preservation effort.
The Beginning Point
The most commonly used maximum for pre-Columbian bison, of 50 to 70 million animals, describes the situation when herds ranged freely from Virginia to Texas to northern Canada. Tracking that estimate back through its various references in scientific literature reveals that this figure originated with Ernest Thompson Seton (1909). To come up with it, he assumed that there were as many bison as the similar-sized livestock that replaced them in the same areas. Because more directly quantitative observations do not exist and more recent studies tend to contradict one another, the only thing absolutely known about the pre-pioneer bison herd size is that there were a lot of them, even if some recent debunkers are correct in hypothesizing that there were fewer than Seton concluded. On the other hand, it is quite certain that a precious few bison remained in the wake of habitat conversion and unwarranted slaughter by the turn of the present century.
The total herd's post-1900 increase, after a start for altruistic and somewhat romantic reasons, has been driven by the animals' steadily increasing commercial value. Journalist Richard Manning's arguable-in-detail, but still generally reliable, 1995 book Grassland reported that the bison herd has recovered to 150,000, while the most recent advertizing flyer from the Denver Buffalo Company, a high-end meat and hide purveyor, touts 250,000. The most commonly visible herd members may be within public parks, but much larger numbers now are found on private land, with their growing presence being justified by their meat and other saleable products. The number of buffalo in these private herds, in groups from one to several thousand, has more than doubled in the past ten years.
Our own bison model (described below) anticipated the last decade's herd recovery rate. If its projections hold as well into the future, within the next 40 years the animals' breeding capability will allow the number of bison in America to once again reach their multi-million pre-Columbian level. Yet, in an era of vanishing open spaces, are there sufficient resources to sustain that many large native animals?
Whether its source is native grassland or agriculture, sufficient feed for 70 million bison is not even much of a theoretical problem. Buffalo convert forage into meat at least as efficiently as cattle do, and properly-managed forage production notably exceeds that of grain on any given plot of land (Yorks, 1976). Therefore, if they are substituted for domesticated animals, bison numbers could be at least as great as those of similar-sized livestock, which currently total roughly 120 million, if the same land used to produce petroleum-assisted feed for those livestock was made more directly available to the bison. A primary question then becomes: is that substitution realistically achievable, given how rare bison still seem to be?
The Bison Model
All models, including this previously unpublished one projecting the regrowth of the American bison herd, are dependent on the assumptions that drive them. Figure 1 depicts the bison model's herd structure, which assumes that these animals begin breeding at 3 years of age.
After this point, adult females have a 70% success rate in bringing calves to weaning age. This choice represents a compromise between results for private breeders, who have achieved weaned calving rates of better than 90%, and natural herd observations of 50 to 60%. Other key baseline assumptions are that one bull is kept for each ten cows; that the unneeded male calves are sold for meat and other products after reaching 3 years of age; that adult death losses equal 3% annually; and that the remaining herd bulls and cows are culled when they reach 11 years of age.
Based on these assumptions, Figures 2 and 3 portray the herd's potential for regrowth over a 50-year period that began 10 years ago, with this regrowth plotted in three separate increments for accuracy of scale and ease in interpretation.
This projection does not change much even if one varies the model's central assumptions, which were assigned conservatively. Setting the calving percentage to a more likely 85% success rate (since most animals would be privately managed) reduces the time needed to reach maximum herd size by 5 years. Doubling the animals' longevity within the herd, which is also quite possible (and almost certainly desirable) with bison, has about the same impact. Together, these practical choices would shrink the potential full recovery time for the herd to just 30 years from now.
Once a desired herd size is reached, the number of bison culled for sale would rise dramatically, just to keep the animals within bounds of their feed supply. At that point, roughly 90% of the 3-year-old females, in addition to excess males, would be sold. At that point, some substantial economic adjustments would be required, as happens routinely within supply/demand cycles among contemporary livestock herds. Whether those corrections are successfully orchestrated or painfully uncontrolled depends on the choices made by producers as a group.
Factors Affecting Herd Expansion
Given the relatively short time frame predicted by the model, why has this seemingly explosive herd growth not occurred sooner? In the early years of recovery, when the management goal was simply species preservation, bison numbers were restrained by the limited resources available for them as simple curiosities. Only recently has there been an economic motivation for herd expansion, an incentive which can allow that growth to come closer to its full potential. Further, at the heart of exponential growth itself is an at least visibly very slow start, and then an apparently sudden, massive response. The bison herd is now approaching this latter stage.
Whether or not the current rate of expansion will be sustained lies in a balance of factors too complex to be fully followed here. Some arguments in favor of bison (relative to cattle) include:
Each of these points leads to greater production profit margins.
- lower fat, better-tasting meat especially when grass-finished that also has potential human health benefits;
- stronger leather, which can be even more valuable with its three-fold greater hair cover; and
- lower production costs, especially when natural foraging characteristics are fully utilized, through their:
- ability to utilize land and plants where cattle will not;
- more efficient digestion of low-nitrogen forage;
- dramatically improved unassisted winter survival;
- effective self-defense against predators and many diseases; and
- higher potential to effectively co-utilize the land with other potentially profitable animals.
Against bison must be balanced:
- the brucellosis controversy (which cattle probably passed on to bison in the first place, but such blame does not make the problem disappear);
- the behavioral unpredictability inherent with bison wildness, as it leads to wandering and violent confrontation with humans;
- increasingly well-publicized philosophical anxieties about eating meat and other uses of animal products;
- technical difficulties in re-establishing the plant and animal communities among which bison best thrive, since nearly all have been seriously disturbed in the interim and seed reserves are limited;
- past and present problems with unscrupulous or simply careless distributors of products, which can be substandard, mislabeled, or flat-out dangerous;
- lack of general knowledge about how to properly care for, and best prepare, meat and other bison products;
- the continuing locally-spotty product supply, with its consequent problems for would-be wholesalers and retailers, until the herd size can fully meet potential demands; and
- during the herd expansion phase, competitively higher brood-stock prices than for cattle.
Further, as long as most bison are being held back for breeding, a shortage of directly marketable meat and hides will continue. That raises price competition for these products, which puts pressure on marginal operators to slow their own herd growth rates in favor of immediate profits, a step which, in turn, can restrain overall herd expansion rates.
Social Feasibility
The over-arching limit to bison expansion, however, is these native animals' requirement for quite large unfenced areas to operate most efficiently and effectively. This productivity question is deserving of considerably more research attention than it has received. Its wider confirmation would, in turn, require social adaptations on the part of humans which are difficult for most people to imagine at the scale required. In purely practical terms, the most effective expansion of the bison herd entails substantial human transportation and active living site restructuring, because existing arrangements rarely consider biological system optimization, either for nature or ourselves.
In the more immediate term, there will continue to be great opposing pressures from today's dominant mechanized-farm oligopolies and their suppliers, which arise from fears for their future place in the scheme of things. There have also been some poorly chosen words from proponents, some of whom have pressed for, or at least seemed to suggest, a top-down imposition of a wholesale property ownership shift, rather than an emphasis on the increased profit potential that could result from more efficient sharing, and on cooperation evolving upwards from many highly local beginnings among neighbors. Anne Mathews (1992) has detailed how Frank and Deborah Popper quite literally needed to bring armed guards to some plains communities when they presented their conceptual fully open "buffalo commons", which was perceived by some as potentially government-imposed, rather than agreed-upon from the grass-roots up, as they intended.
The familiar is always heavily defended, no matter how obviously inappropriate it may be in the general case, because of its apparent convenience and comfort in particular instances. Most humans have a hard time clearly imagining better circumstances, whether or not we currently "have it good". Accordingly, better communicators are vital, particularly among those who have a more hands-on role in expanding the bison herd. Individual landowners need to be able to fully visualize that change to bison, to naturally complex vegetation instead of grain, and to cooperative land management all have more direct positive economic and lifestyle benefits than do continuing present land use patterns.
In the not-so-much-longer run, native animal herd growth is ultimately circumscribed by beliefs that human population growth rates (and/or material and/or energy use) do not yet need restraint. Bison would have little place on a planet that resembles Isaac Asimov's fictional Trantor, i.e., metallically roofed over and densely packed with nothing but people. Some limited progress in restraint in human population growth has occurred in some parts of the United States and Europe, but worldwide this increase continues on a frighteningly upward exponential curve.
The Question of Bison Distribution
To return more closely to accessible science, in the more than 20 years that we have been reading almost everything published about the ecology and the human utilization of bison, as well as actively watching the animals directly, we have encountered a great many arguments about the way that these animals distribute themselves across the land. Many of those often diametrically opposed contentions, varying from massive seasonal migrations to essentially randomized stasis, have been presented persuasively. We will not try here to resolve that specific question, but to just briefly put it in comparative context to domestic livestock. Cattle may nearly always be found within one mile of open water (and usually even closer to it), while bison range at least five times further, with less damaging use of difficult terrain. Sheep movements must be actively constrained by fences or human herding, since selective breeding has caused them to lose, as with cattle, their independent ability to survive. Both domestics focus tightly on a relatively few plant species within those bounds, which, if not very carefully managed, results in an ecosystem shift towards dominance by the less desirable alternatives (Heitschmidt and Taylor, 1991).
On the other hand, two scientific concepts normally used in other contexts give an apt description of how bison distribution differs from that of domestic grazers. From a practical functional perspective, the long-term unrestrained presence of bison on any particular piece of ground approaches randomness, with an intensity of use proportional to the availability of food resources on it, and the reasonable availability of water. Their short-term distribution is most likely to be predicted by chaos theory, where small, localized perturbations (generally not noticed by us) create large changes in distribution. This unpredictableness is an effective response to the vagaries of weather and other patterns that affect plants, and to the broader range of spatial and species choices in grazing made by bison. These result in an increase in system diversity with bison present (Hartnett et al., 1996), instead of the decrease that tends to follow domestic animal grazing. Most importantly for the current discussion, this positive effect increases with the area over which the bison are allowed to range without restriction.
In the simplest terms, bison are a keystone product of 4 billion years of evolutionary experimentation (i.e., nature's genetic engineering, with its winnowing process having been carried out on a scale that human plant and animal breeders could never even hope to approach) on how best to produce meat from North American soils and climate. Wherever we compromise this native ability to function, we correspondingly will reduce both production potential and the long-term health of the ecosystems that support it.
Selective breeding for various attributes has already been tried, at great expense, with what have become our domestic livestock. These started out long ago as well-adapted species themselves, but had many vital survival values bred out of them. As good university animal breeding classes teach, whenever one attribute is selected for (such as conformation or quick weight gain), something else is inescapably not included in that animal's genetic makeup. What is lost thereby inevitably turns out to be important in some situation unanticipated by the breeder. Those who seek to selectively breed bison need to keep this history in mind, while routinely reminding themselves of the meaning of the Greek word hubris, and of why bison have been able to do as well as they have.
The Broader Ecological Picture
Bison cannot regulate the whole ecosystem by themselves. Prairie dogs and other burrowers aerate and circulate the soil. Antelope and deer help keep the plant species balance by their concentration on shrubs and forbs, while elk, bighorn sheep, and rabbits have seasonally mobile pressures and other appropriate selectivities. Predators keep the smaller grazers' numbers in check, and weed out the diseased. As a basic rule, the more of these coworking species there are, the more stable the system is likely to be, as the more obvious parts, in turn, provide for the needs of the still smaller animals, whose invisible (to us) effects are in sum even greater.
The same principle, of course, applies to the plant part of the life spectrum, upon which both bison and soil stability depend. Human activity has greatly disrupted the complex makeup and interactions that were present two centuries ago across the bison's range. Tremendous quantities of soil (or at least functional soil structure) and deeply stored nutrients have been lost in the interim. Hardy, invasive species have been introduced into the damaged environment, while vital native components have been reduced to isolated enclaves. Recreating the full potential of the web of interacting species, which can so much better respond to vagaries of climate, disease, and animal utilization, will require an intense effort by generations to come.
Almost certainly there was and is a readily harvestable, sustainable surplus available for humans from fully-functional natural systems. It is possible for us (as our ancestors did for thousands of years) to satisfyingly nourish ourselves from this surplus, albeit with shifts in eating and other habits. Modern refrigeration and sanitation knowledge, and its reduction of spoilage waste, makes it possible for a far larger human population to be maintained from the same plant and animal production pool than was possible in the distant past. Tragically, just how large this once and potentially valuable surplus could be has never been adequately studied. However, there are many positive feedbacks integral to fully-functional natural systems. Complete natural systems make available a larger net gain than is possible from fossil-fueled attempts to supplant them. This comparison becomes increasingly valid as secondary as well as primary costs are considered, and especially as time horizons longer than one year are factored into the accounting.
If that practical underlying expectation, which is generally overlooked by the agricultural industry, is taken as fact, then the question of allocating that potential surplus becomes a more important one to confront. Our present land management structure, from land use to the distribution of products from that land, was determined by property borders that evolved from very different locations and expectations. Those European small farms, as they evolved out of the feudal system and which are still used as the theoretical American model, arose in a period where neither comparative productivity calculations nor technological advances in particular freezers, electronic communication, and ready transportation were available. Practices applicable to intensive vegetable culture in consistent precipitation climes hardly seem the proper paradigm to continue to cling to in the harshly variable environment of central North America, especially when a better meat production model, one provided by millennia of natural evolution, is available.
Herding
As pastures become more optimally extensive, producers must deal with the issue of herding. Currently, the advantages in long-term production values from fence consolidation are being negated on many ranches by increased off-road vehicle utilization to manage animals. Overall damage to vegetation resources may quickly be calculated by multiplying length and the number of passages times vehicle width and weight (Yorks et al., 1997). Such abuse can be dramatically reduced by recent technical advances that can be applied to herding practices, such as satellite-computer-GPS monitoring of herds (and even individual animals), and ultra-light aircraft delivery of veterinary services. These innovations can be cost-effective in comparison to the full sum of expenses for land-based vehicles, round-ups, and intensive fencing, even without considering the longer-term costs of soil and vegetation impacts that are caused by current vehicle-use practices.
Marketing
Problems have occurred in the past because broadly scattered bison producers did not have access to consistent markets, and because chefs and cooks rarely knew how to handle the extremely lean bison meat properly. The sale of buffalo products also has been dogged by unscrupulous distributors, who have passed off the meat of sick twenty-year-old bulls as prime quality, or have not taken proper care in product processing or storage. A memorable personal example was the purchase of a buffalo tongue that had been packed still covered with rumen fluid, which was annoying to cooks knowledgeable about what had happened (the apparent foulness could simply be washed off), but which might have turned almost anyone else away from the meat source. Each such incident holds back potential herd growth rates by constricting the repeat-customer market.
Paralleling the history of beef, as the bison market matures, brand names and more dependable quality preservation procedures should assure consumers that they will get what they pay for, while producers will be more consistently able to reach the right customers when the animals are ready. Stricter inspection procedures are becoming more common. However, this does not mean that a steep growth-curve will not be leveled from time to time as other abuses occur, so that consumers will be turned away from the products not through inherent problems, but following chicanery or carelessness during distribution.
Central to present market limitations is the dichotomy between the theoretically lower production costs for bison and the three-times-higher-than-beef prices typically found in the market place, at least for the premier cuts. Part of this problem lies with the intrinsically higher costs for slaughter and distribution that result from a relatively low volume of animals being processed. Much more of it comes with the difficulty of selling the now-perceived-to-be lower-quality cuts (e.g., the "trim", as opposed to steaks and roasts), and the variable tastes that can result from grass finishing. Based in part on personal experience, this problem can be overcome through the explosive growth of interest in cuisine, as opposed to just cooking. The industry needs to work more closely with top chefs as a part of getting the word out about just how much tastier bison meat is, including the braisable portions of the animal, and of how variation can create more interesting dishes. Lean bison's tendency to make comparatively dry-tasting hamburger need not be thought of as a limitation. Grinding meat dramatically reduces its keeping and safety quality anyway, while only minimal additional effort in cooking the unground meat results in more appetizing products.
The beef and pork industries have, albeit painfully and grudgingly (having listened first-hand to some of the acrimonious protestations of poverty), collected a penny per pound at the time of slaughter, and used this money for consumer education. This has, after the inevitable latency period, been paying off handsomely with a turn-around for what was a declining market. The bison industry has a far more interesting product, with a better story to tell. Where are that tale's effective tellers, and why are producers not remembering how the phrase "penny wise and pound foolish" become an aphorism?
Because bison still have a relatively small place in the overall meat marketplace, there is a greater potential to create a more rational distribution system than the one now in place for beef. The optimal harvest time both from a meat and hide quality standpoint, and from over-wintering weight losses, is in the late fall or early winter. Further, practical marketing vagaries make fresh meat a wasteful process, through spoilage in mismatches between immediate demand and supply. This mismatching is particularly an issue for an effectively new product such as bison meat, where customer caution at first reigns, and supplies are inconsistent.
In an example calculated for beef, the feed cost and weight loss during wintering, combined with spoilage losses during fresh distribution, resulted in an overall higher energy efficiency for carefully frozen products from a fall harvest than from a year-round meat supply (Yorks et al., 1980). Bison hide quality and overwintering stress losses should be comparably improved by fall-only versus year-round harvests. Further, the inherent fresh-meat spoilage factor is great enough that averaged final product quality tends to be higher via a well-managed frozen distribution pathway. The key problems with frozen meat (historically contributing to consumer resistance) are initial freezing care and subsequent temperature maintenance. Older home freezers (and some less expensive current ones) tend to vary greatly in their internal temperature, and distributors have often been less than effective in frozen storage quality control. For example, package tell-tales, which irreversibly change color if the temperature has risen high enough to damage quality after the product has been frozen, are commercially available, but are not commonly being used. A primary need is for consumer education about the comparative value of frozen products, once the quality issue has been fully understood and acted upon by producers and distributors.
These basic technical quality problems can be neatly addressed, along with some key social parallels, by fully-inspected mobile slaughtering, whereby the bison, which respond even less well to handling than cattle, would not be stressed by transport and holding prior to processing. By carefully distributing the consequent release of inedible portions of the processed bison back to the pastures from which they came, system-level nutrient balances would be more easily maintained, and these by-products would remain as nutrients, not become concentrated pollution sources. From the mobile slaughter centers, the immediate distribution of meat and allied products would be to local communities for storage in controlled centers where more efficient freezing could be maintained until the final sale of products, which should be shortly before consumption. Completing value-added processing locally, before the products reach urban markets, could bring many more dollars to the rural communities that now stand in so much need of employment sources.
As a paradoxical market potential, updating native processing techniques may have just as large an outreach as frozen distribution. The characteristics of bison are inherently attractive to the burgeoning health-through-food, organic perspectives consumers, especially when the animals are grass finished in areas where chemical weed controls are eschewed. The backpacking and travel markets are just a portion of the groups who could be attracted to smoked and other naturally dried or preserved bison products made with full attention to the best contemporary understanding of requisite sanitation controls.
Society's appreciation of the advantages of low-fat, disease-resistant bison meat should increase with the products' availability, if quality control and getting the message out can be sufficiently assured. With world markets included, given the current and anticipated rates of human population growth, the potential demand for bison products exceeds the absolute capability of North America to produce it.
The Future Foreseen
Growing grain for selectively-bred and fed cattle has had impressive cash flows, but the overwhelming bulk of that money has ended up with the suppliers of fuel, machinery, and chemicals, and the banks behind them. Heavy mechanization has not provided an improved net return to farmers (Kraybill, 1989). Some within the bison industry want to follow this same highly questionable path. Although the definitive scientific comparisons remain to be completed, the interacting complexities of natural systems clearly provide a mechanism for a higher total nutrient capture per land unit without expensive, destructive, and wholly unsustainable subsidies. Projecting a once-again-dominant bison herd links us to a more golden past, bringing with it a great potential for dramatically increasing associated species numbers (of both native plants and animals), and reducing fossil fuel use, pollution, and soil loss by decreasing the role played by mechanized agriculture. Each of these, in turn, can lead to better quality products, decreased production costs, and increased net profits. These factors should furnish sufficient reason for putting up with any associated pain that large-scale change brings, especially if those profiting particularly well from the current system realize that they can gain the most by going with a more reasonable flow than the one most follow now.
The capitalist principle still operates in the United States. Therefore, because bison have a greater profit margin available than cattle, we can expect that increment to provide the primary impetus to make the changeover from the latter to the former. Repeated alerts that a switch from cattle to bison is both possible and likely, particularly if this advice is widely appreciated, should furnish a parallel motivation to much more seriously examine responses to its social implications.
All of this started with a few dedicated, but practical, environmental preservationists. With a change from cattle to bison, and with the benefits associated with this transposition, we could regain a large part of what can be visualized as Eden, in what could be an amazingly short time. In just the past ten years, without many being aware of the movement, one little model together with the more substantive support extant for the factors used in evaluating its projections indicates that we have reached nearly one-third of an extremely realistic possibility.
The largest remaining challenge is to develop the management and marketing pathways that will avoid past mistakes, and take fuller advantage of human, plant, and animal potentials for cooperation. The ecological and economic potentials provide the impetus to do so. The bison are coming back. Will we reach out and give them back the world they deserve, as they, in turn, provide a better world for us?
Acknowledgments
To Neil E. West at Utah State University, who provided the support that got us to South Dakota to begin re-exploring the bison question, and the equipment to further this study, including final production of much of this presentation. To Fred DuBray (Brings Back Buffalo), the Cheyenne River Sioux (Lakota) Tribe, the Bureau of Indian Affairs, and the U.S. Department of Agriculture, whose support furthered the development of these ideas during the completion of parallel projects. To High Level Research, which paid for the time to get the job both begun and done.
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Slightly revised, converted to HTML, and posted on-line 20 November 2001
Reformatted 12 November 2002.