“The Incredible Shrinking Bison” [1] discussed how the increase of CO2 emissions has contributed to the rise of the Great Plains’ average temperature, and how the resulting warming trend has affected the bison. The bison, on the other hand, as a key species to the survival of the plains, can also have an indirect, mitigating effect on the CO2 levels in the atmosphere.

The predominate conversation around atmospheric CO2 has centered on the elimination of CO2 production.  There is, however, another conversation underway—one involving the removal of CO2 from the atmosphere. The process of capturing and storing atmospheric carbon dioxide is known as carbon sequestration.  It is one method of reducing the amount of carbon dioxide in the atmosphere, and consists of two types: geologic and biologic.  Geologic carbon sequestration involves the storing of carbon dioxide in underground geologic formations.  The CO2 is usually pressurized until it becomes a liquid, and then it is injected into porous rock formations in geologic basins [2]. 

Biologic carbon sequestration refers to storage of atmospheric carbon in vegetation, soils, woody products, and aquatic environments. For example, by encouraging the growth of plants—particularly larger plants like trees—advocates of biologic sequestration hope to remove CO2 from the atmosphere.  Within biologic carbon sequestration there are several means by which CO2 is removed from the atmosphere.  These include peatland, wetland, forestry, agriculture, carbon farming, deep soil, and ocean-related. But of all the terrestrial (as opposed to aquatic) methods, the forests receive the lion’s share of the world’s attention.  Forgotten are the grasslands which also harbor much of the wetlands. For North America the grasslands of the Great Plains and prairies, which occupy approximately one-third of the continent, are critical to carbon sequestration.  And key to the grasslands’ vitality is the North American Bison [3].

Grasslands quickly process carbon from the atmosphere and store this carbon in the root structures, which extend 8 to 15 feet into the ground, which can store 22.5 million tons of carbon. These roots can hold the carbon for decades, and process 1.7 million tons of carbon per acre to the soil annually.  This storage accumulates over time and moves carbon from the atmosphere to the ground continuously creating massive carbon deposits over the course of centuries. Prairies have the ability to store as much carbon below the ground as forests can store above the ground. When carbon is stored below ground it remains locked there and unable to enter the atmosphere.  Compared to forests, grasslands are more reliable.  In times of drought and forest fires, the carbon stored in the wood and leaves returns to the atmosphere.  During a grass fire, however, carbon is not released since it is stored in the roots underground [4].

School of Environmental Sustainability-Colorado State University [5]

Though the Great Plains and prairies occupy a vast swath of the North American continent, this does not translate into a great CO2 scrubber.  The conversion of this ecosystem into cropland has significantly reduced the ability of this region to sequester carbon [6]. Compared to native or natural vegetation, cropland soils are depleted in soil organic carbon (SOC).  When soil is converted from its native state the SOC content in the soil is reduced by approximately 30 to 40% [7].  Further, the crops replacing the native grasses are annuals with comparatively shallow root structures which are less effective in storing carbon and holding soil.  With less carbon stored and moved to soil, and increased possibility of soil loss, the effectiveness of the plains and prairies in atmospheric CO2 removal is significantly decreased.  

Short of returning the croplands back to the natural state of the region, there are agricultural methods aimed at sequestering atmospheric carbon into the soil and in crop roots, wood and leaves.  These methods are collectively referred to as carbon farming.  Besides removing CO2 from the atmosphere, increasing the soil’s carbon content—whether by reverting to the natural condition, or by carbon farming—aids plant growth, increases soil organic matter which improves agricultural yield, improves soil water retention capacity and reduces fertilizer use which is a source of the greenhouse gas nitrous oxide (N2O) [8].

Carbon farming or recovering the native perennials, however, is not the complete answer.  The ecosystems of the plains and prairies were dependent on the large herds of bison moving over the grasslands.  The grazing, trampling and recovery patterns associated with the bison were key in building soil, maintaining biological diversity and deepening plant roots, which are crucial elements in permanent carbon sequestration [9].  The bison not only provided nutrients for plant life, but tilled the soil with their hooves, working up and trampling dung into the soil, enabling plant-life to take hold, flourish and consequently become a significant carbon sink.

School of Environmental Sustainability-Colorado State University [10]

Though sequestration, as used here, is a technical term, the concept is quite familiar. When we hear the word “sequester,” the common association is with juries as in jury trials.  When a jury is sequestered, it is removed and kept apart from contact with the public.  The purpose is to ensure undue influence on, or tampering with, the deliberations of the jury, and ensure a just verdict.  As the jurors file out of the courtroom at the end of the defense’s and prosecution’s final presentations, if the judge has ordered they be sequestered, we see the tangible form of a removal to protect the integrity of the trial by jury justice system considered critical to our legal well-being.  The notion of using an act of removal in the protection of our well-being is only part of the meaning of sequestration.  What is being removed and where it is being kept are equally important.  Originally, “to sequester” meant “…to put in the hands of a trustee…” [11]. In regard to carbon sequestration the trustee is the earth itself, or more specifically, in the context of the bison and the grasslands of North America, it is the Great Plains ecosystem.  When we think of ecosystems, we tend to think of the land, the flora and the fauna.  Often missing in our consideration is the air above.  The bison—a  keystone species in regard to the flora and fauna and the land—is a crucial element of the trustee,  instrumental in the process of CO2 removal and the mitigation of the warming trend plaguing the Great Plains.

End Notes:

[1] Schuette, Keith. “The Incredible Shrinking Bison.” November 17, 2020.Bison Witness.

[2] “What is Carbon Sequestration?” What is carbon sequestration? ( Retrieved 4/24/21

[3] Schuette. “Dung Cake and Feces Pie: Yum!” April 26, 2019. Bison Witness.

[4] Davidson, William, “The Great Plains: America’s Carbon Vault” (2016). Op-Eds from ENSC230 Energy and the Environment: Economics and Policies. 73.

[5] Lavelle, Jocelyn. Soil carbon sequestration to combat climate change—a real solution or just hype? – Sustainability ( Colorado State University—School of Environmental Sustainability. Retrieved 4/30/21.

[6] 42% of the Great Plains has been converted to cropland, leaving 53% intact.  The remaining 5% holds water or has been converted to human use.  Understanding Grassland Loss in the Northern Great Plains. 2018. World Wildlife Organization.

[7] Poeplau, Christopher; Don, Axel (February 1, 2015). “Carbon sequestration in agricultural soils via cultivation of cover crops – A meta-analysis”. Agriculture, Ecosystems & Environment. 200 (Supplement C): 33–41. doi:10.1016/j.agee.2014.10.024.

[8] “Carbon Farming | Carbon Cycle Institute”. Also, “Carbon Farming: Hope for a Hot Planet – Modern Farmer”. Modern Farmer. 2016-03-25.  And Velasquez-Manoff, Moises (2018-04-18). “Can Dirt Save the Earth?. The New York Times. Retrieved 4/30/21.

[9] Wright, Pam. Bison: The Latest in Carbon Capture Tech.12/24/2017/by Regeneration International. Retrieved 4/30/21.

[10] Lavelle.

[11] Webster’s Unabridged Dictionary of the English Language. 2001. Random House.

What’s for Dinner?

The question is: what does a 2000-lb adult male bison eat?  We may be tempted to reply, “Anything he wants.”  We would be both right and wrong.  In some sense he does eat what he wants.  His biology, however, dictates what he wants.  So what are the favorite entrees of bison?

Bison diet tends toward grasses and sedges—grass-like plants with solid stems—but are now known to consume a wide-variety of plants including woody plants and herbaceous eudicots [1]. The eudicots are a diverse and abundant group of angiosperm plants. They include over half of the species of all plants and are found in a huge variety of habitats. Being angiosperms they are seed-bearing, vascular plants that produce flowers, fruit and pollen. They are also often woody plants and can grow into giant, long-living trees [2].  Examples of eudicots include dandelions, buttercup, maple, and magnolia. 

Sources of Protein Intake for Bison—

Eating from eudicots as opposed to grasses and sedges defines a species as a browser. Browsers glean leaves, bark, and green stems from plants, while grazers clip vegetation at or near ground level.  Browsing has a distinct advantage when grasses and other ground-level vegetation are covered by deep snow. The disadvantage of browsing is that height may make vegetation inaccessible. Another disadvantage is often-times browsers eat parts of the vegetation that are low in nutrients, chemically defended, or both. Grazers, such as sheep and cattle, can, when grasses are accessible, feed on the much more nutrient-rich meristematic [3] regions of the grasses [4].

The American Bison is not just a grazer, but also a browser.  However, their preference of entrees is for the grasses and sedges, and instinctually they seek the more nutrient abundant grasses.  Efficient acquisition of nutrients, then, is a primary driving force in this selection. Apparently, the bison evolved to take advantage of the nutrient production of grasses.

In the production of nutrients, and specifically proteins, plants require carbon.  The perennial grasses of the Great Plains and prairies are of two types—C3 or C4—in regard to carbon fixation (the acquisition and preparation of carbon for the production of nutrients). These terms refer to the different pathways that plants use to capture carbon dioxide during photosynthesis. All species have the more primitive C3 pathway, but the additional C4 pathway evolved in species in the wet and dry tropics. The first product of carbon fixation in C3 plants involves a 3-carbon molecule, while C4 plants initially produce a 4-carbon molecule that subsequently enters the C3 cycle.

The two pathways are associated with different growth requirements.  C3 plants are adapted to cool season establishment and growth in either wet or dry environments.   On the other hand, C4 plants are more adapted to warm or hot seasonal conditions under moist or dry environments.  A feature of C3 grasses is their greater tolerance of frost compared to C4 grasses.  C3 species also tend to generate less bulk than C4 species; however, feed quality is often higher than C4 grasses [5].

C3 grasses are more efficient fixing CO2 at cooler temperatures. However, at higher temperatures, above 90 degrees, C3 grasses have difficulty differentiating between CO2 and O2. In hot weather C3 grass can also catalyze the fixation of O2 in equal or greater portions as CO2. This is significant. When O2 is fixed, the process is called photorespiration, and the result is lowered carbohydrate production. When photorespiration occurs, growth slows, and without water, the grass will often go dormant.

C4 grasses—warm season grasses—on the other hand, are more efficient at CO2 fixation in high temperatures. This occurs because C4 grasses use a different enzyme than C3 and attach the CO2 to a different compound making up the 4-carbon compound. While it takes more energy for C4 to produce carbohydrates than C3, because of the extra steps involved, the process proceeds without photorespiration with the end result a greater carbohydrate production [6]. 

The differences between the C3 and C4 grasses become significant when considering bison dietary habits and the warming trend occurring across the Great Plains. Under the warming conditions, the nutrient production of C3 grasses becomes less efficient, and with the increased frequency of associated droughts [7], may even go dormant. The C4 grasses may then increasingly become a larger portion of the bison diet, since these grasses do well in higher temperature.  However, studies reconstructing seasonal variation in the diet of North American bison in two grasslands found the bison in the warmer grassland consumed a lower proportion of C3 grasses, but not a greater proportion of C4 grasses.   Instead, bison turned more to the N2 fixing eudicots, i.e., shrubs and forbs, which comprised as much as 60% of their protein intake.  The N2 fixing eudicots contain a higher concentration of protein than either C3 or C4 grasses, which may explain why bison turn to eudicots as a nutritional source over C4 grasses, when C3 grasses are not as abundant.  As the warming trend continues, buffalo may have to compensate through the browsing of eudicots.  Minimizing the warming-imposed nutritional stress may require the promotion of high-protein eudicots or the facilitation of increased protein concentrations of grasses [8]. 

In the previous blog, “The Incredible Shrinking Bison,” the conclusion emphasized land and vegetation management development. That effort requires an understanding of why bison turn to shrubs and forbs as opposed to consuming a greater proportion of C4 grasses under warming conditions.  In addition, research into how to promote greater protein production and concentration in grasses and eudicots is critical.

End Notes:

[1] Flowering plants with two seed leaves upon germination as opposed to monocots such as grasses and grass-like flowering plants.  Eudicots. Wikipedia. Retrieved 19-March-2021.

[2] Eudicots | Basic Biology. Retrieved 19-March-2021.

[3] Meristem. Botany.  Embryonic tissue growing, actively dividing in plants.  Webster’s Unabridged Dictionary of the English Language. 2001. Random House.

[4] Browsing versus Grazing ( Retrieved 19-March-2021.

[5] What are C3 and C4 Native Grass? ( . Department of Primary Industries. Retrieved 19-March-2021.  Also: Difference Between C3 and C4 Plants | Compare the Difference Between Similar Terms. Retrieved 19-March 2021.

[6] Understanding C3 & C4 Grasses | AgriGro®.  Retrieved 19-March 2021.

[7] Craine, J. M., Nippert, J. B., Elmore, A. J., Skibbe, A. M., Hutchinson, S. L., & Brunsell, N. A. (2012). Timing of climate variability and grassland productivity. Proceedings of the National Academy of Sciences, 109(9), 3401– 3405. Retrieved 19 March 2021. Also Martin, Jeff M., Perry S. Barboza. 06-Dec-2019.

[8] Craine, Joseph M., E. Gene Towne, Mary Miller,  & Noah Fierer. (16-Nov-2015). Climatic warming and the future of bison as grazers. Scientific Reports. Nature.  https// reports. Retrieved 19-March-2021.

The Buffalo Nation Returns

Integral to Native American cultural and spiritual heritage is the American Bison—our National Mammal.  The revival and reclamation of this heritage cannot be divorced from the recovery and preservation of the buffalo.  As the First Nations—especially the Plains tribes—rebuild their cultural foundations, restoring the bison is critical to those efforts.  Incarnations of this spiritual endeavor are witnessed by Native organizations dedicated to bringing back the Buffalo Nation, including the Inter Tribal Buffalo Council, The Tanka Fund, and The Buffalo Treaty [1].

The Inter Tribal Buffalo Council was not the first endeavor of the First Nations to bring back the Pte Oyate [2].  Prior to 1991 Native American tribes had been attempting to restore the buffalo to their respective tribal lands.  Their efforts, however, were singular which presented particular challenges.  Many of the tribes lacked sufficient experience in raising buffalo and needed guidance.  In addition, there were little or no efforts to reintroduce the traditional, cultural and ecological contributions of the bison.  Out of these challenges arose the recognition a centralized, concerted response was required.

From the Inter Tribal Buffalo Council Website

In February 1991 nineteen tribes gathered in the Black Hills of South Dakota to form a more effective means of restoring the buffalo to tribal lands.  This initial meeting was hosted by the Native American Fish and Wildlife Society in which emerged the original interest group—the founders [3].   Established during that meeting was the organization known as the Inter Tribal Buffalo Cooperative  (ITBC) with the mission of:

“…restoring buffalo to Indian lands in a manner which promotes cultural enhancement, spiritual revitalization, ecological restoration, and economic development compatible with tribal beliefs and practices.”

To advance this mission the Cooperative saw its role as:

“…to act as a facilitator in coordinating education and training programs, developing marketing strategies, coordinating the transfer of surplus buffalo from national parks to tribal lands, and providing technical assistance to its membership in developing sound management plans that will help each tribal herd become a successful and self-sufficient operation [4].”

In April of the following year, 1992, the ITBC became officially recognized as a tribal organization. It was incorporated in Colorado and headquartered the following summer in Rapid City, South Dakota.  Though the name was changed slightly to the Inter Tribal Buffalo Council, the mission statement and the role of the ITBC remained the same.

Since its establishment the ITBC has grown to include 69 federally recognized tribes from 19 different states.   To date the Council has restored more than 20,000 buffalo to Tribal lands with the member tribes–who manage more than 32 million acres—restoring bison to approximately one million of those acres [5].  The management approach has been holistic and thus, hands-off.  As such, the herds are allowed to be free-ranging as much as political and geographic locations will allow [5].  

As impressive as the numbers are, the deeper significance of the ITBC’s efforts lie in the cultural, spiritual and ecological restoration that has taken place.  The return of the Buffalo Nation has allowed the First Nations to advance the recovery of their heritage and deepen the restoration of their spiritual identity.

Restoring the bison does not just happen with dedicated people.  The resources needed to carry out the necessary activities, the transfer of buffalo, the acquisition and preparation of land, etc., require critical funding. The ITBC carries out its own funding activities to achieve its goals.  But other organizations work on funding restoration efforts outside of the ITBC.  One such organization is the Tanka Fund.

Located in Kyle, South Dakota on the Pine Ridge Reservation (Lakota), the Tanka Fund is a 501(c )(3) non-profit corporation.  Its mission is to:

“… bring back buffalo to Indian Country. We offer all people a way to participate in supporting the buffalo’s return! Tanka Fund’s mission is to direct funds from people like you who are stewards of the Earth, proponents of regenerative agriculture, and defenders of social justice to Native buffalo ranchers to support and sustain ranch planning, financing, and operations [6].”

The mission is accomplished through Tanka Fund’s Return Campaign which raises funds through donations.  These funds are then directed to Native buffalo ranchers to support and sustain ranch planning, financing and operations.  Similar to the ITBC, the Tanka Fund also provides technical assistance to Native ranchers on ranch planning, implementing and sustaining best ranching practices, and enabling them to participate in the value-added bison markets.

Placing emphasis on the cultural and spiritual aspects of the restoration efforts, The Buffalo Treaty was first signed in 2014.  The Treaty, which has been signed by many First Nations both in the United States and Canada, is an acknowledgement and expression of the special relationship between the Buffalo Nation and the First Nations.  The signers have expressed their solidarity with the Buffalo People and a commitment to work toward the cultural and spiritual restoration of their unique union [7].

From the Buffalo Treaty Website

The restoration of the bison is not just about pulling them back from extinction or preserving genetic purity or ecological preservation.  The revitalization of the First Nations is also at stake, which extends to the preservation and deepening of our country’s identity.  Despite our country’s earlier genocidal history toward the Native Americans, we have to admit their history is now integral to our identity.  The bison is not just an ecological keystone species, it is also a spiritual keystone to our society.  The actions taken by organizations such as the ITBC, The Tanka Fund and The Buffalo Treaty, are critical to all of our identities, and, as such, they deserve our support.

The extent of the work and significance of these organizations can only be hinted at in this post.  The reader is encouraged to go to the respective websites for a complete history and scope of their activities and accomplishments.

End Notes:

[1] See respective links under the Favorite Links tab for the Inter Tribal Buffalo Council, The Tanka Fund, and The Buffalo Treaty.

[2] This is the Lakota name for Buffalo Nation or Buffalo People. 

[3] Zontek, Ken. 2007.  Buffalo Nation. University of Nebraska. 76.

[4] Zontek. 76-77.

[5] Inter Tribal Buffalo Council.

[6] Tanka Fund.

[7] The Buffalo Treaty.

Pronghorn: A Bison Associate

Except for a lone red-tailed hawk flying high above, the high plains appear to be scrubbed of animal life.  Yet, a sense of being watched cannot be helped.  A scan of the surroundings does not reveal anything at first.  Suddenly, a flash of brown darts across the vista and just as suddenly stops.  Two big black orbs stare back.  The watcher is being watched.  In the distance, barely perceptible among the flora stands a pronghorn, assessing the newcomer to its territory for potential danger.  Discerning none, yet it remains still, vigilant. 

The pronghorn, commonly referred to as the American pronghorn antelope [1] or just American antelope, is not an antelope.  Its scientific name is Antilocapra Americana which means American antelope goat.  However, it is neither antelope nor goat.  The pronghorn has no close relative, being the surviving descendent of an ancient family of herbivores extending back 20 million years [2].  The more common, shortened name of pronghorn derives from the pronged horn which can grow to a foot long on males.  Different than antlers of a deer or elk, pronghorn horns grow around a bony, skin-covered core that is not shed. The horns of pronghorn are also different than buffalo horns.  For the pronghorn the outer sheath of keratin that makes up the horn is shed and regrown [3].

The Pronghorn

When Lewis and Clarke made their way across the Great Plains in their journey to the Pacific Ocean, pronghorn numbered in the millions much as the bison did.  The range of this smallest ruminant in North America, extended from the plains of south-central Canada—Saskatchewan and Manitoba—south through a large part of the western United States and into Mexico.  Great herds ranged from the Mississippi River to the Pacific Ocean lapping the shores of central California, and from the Gulf of Mexico to the Pacific Ocean in southern California.  Now, their numbers are much less, and their distribution restricted to pockets of isolated habitat within the pronghorn’s original range.  The presence of highways, railways, fencing, and other human imposed barriers prevent movement of the pronghorn [4].

Pronghorn share the same range, foraging and watering with the bison, yet they do not compete.  The bison consume mostly grasses while the pronghorn graze on forbs (broadleaf plants such as wildflowers, milkweeds, etc.) and shrubs which benefit from bison activity.  Bison disturb dominant grass communities by trampling, wallowing and grazing, which result in greater production of forbs and shrubs favored by pronghorn.

Pronghorn are picky eaters.  Small bodies need less food but better food.  The smaller a warm-blooded animal is, the more of its body warmth is lost to the air, and to compensate, the higher its metabolism must be, requiring a higher quality of food.  Grasses that have been clipped off retain the growing portion—close to the root, where most of the protein resides.  This is a source of high quality sustenance [5]. Bison do not eat grass down to the root.  Rather they clip the grass off just above the ground, which leaves the younger growing portion for other grazers such as the pronghorn.  Bison also provide for the pronghorn, as well as other species, during the winter.  In areas of deep snow, bison grazing activity push away the snow with their massive heads, exposing forage for others [6].

The forbs, however, make the life of the pronghorn possible.  Forbs contain more protein and less lignin [7] than grasses.  Since forbs grow in patches among the grasses, pronghorns have a different relationship to the grasslands than the bison’s.  For bison the grasses go on forever, which renders selective grazing rather moot.  For the pronghorn, however, grazing is much more selective, which necessitates moving from patch to patch [8]. 

Unlike the bison pronghorn are devout territorialists due to their grazing needs.  Again, it is about the grassland.  For bison the grassland is more or less grassy everywhere.  But for the pronghorn it’s about the patches of forbs.  A bison bull needs only worry about laying claim to the cows. It does not have to worry about staking out a grazing territory.   The pronghorn buck, on the other hand, needs to worry about food sources to carry on its progeny.  This small associate of the bison, then, expends much effort in marking its territory by urinating and defecating in strategic spots to ward off other bucks. 

Bucks guarding territory is not the only worry of pronghorn.  Bucks, does and fawns keep a careful eye and a watchful curiosity on their surroundings, allowing them to detect danger early on.  The most inquisitive of all the bison’s grassland associates, the pronghorn—with its large, dark eyes—has a keen, wide-ranging vision, and is able to spot predators at great distances.  Movement can be seen up to 4 miles away [9].  If an approaching predator is spotted, near-by pronghorn are signaled.  In time of danger the stiff hair on the rump bristle and rise, becoming a broad patch of white.  These rump displays telegraph signals across the terrain, warning other pronghorn of the impending danger [10]. If the danger is warranted, an adult pronghorn can break into a run at speeds reaching 55 miles per hour and sustaining that speed up to a half mile, making it the fastest land animal in North American.  In terms of peak speed, the only other faster animal is the cheetah of Africa, which can reach 80 miles per hour.  In regard to sustained speeds, however, the pronghorn can maintain speeds greater than the cheetah over longer distances.  For instance, the pronghorn is able to run several miles at over 30 miles per hour [11].    An adult pronghorn can easily outrun any of its predators.  Some scientists believe the pronghorn developed such in speed long ago to escape the American Cheetah, a fast ambush predator, which went extinct about 12,000 years ago [12].

Pronghorn Running

A pronghorn’s predators include coyotes, bobcats, mountain lions, golden eagles and wild dogs, which primarily target fawns.  The pronghorn’s main defenses include its keen eyesight and its speed.  The best defense for a fawn is to find cover, lie down and remain motionless while its mother or other adult pronghorn lure the predator away [13].

Pronghorn Fawn

Two hundred years ago pronghorn numbered in the millions but by the 1920s they had suffered the same fate as the buffalo.  Unregulated hunting, drought, and human activity had caused those numbers to plummet, resulting in less than twelve thousand pronghorn.  Since the early 19th century, however, conservation measures and the elimination of hunting seasons have brought back the pronghorn.  One measure particularly effective was the modification of fencing.  Pronghorn are highly migratory and such constructs as fencing can present a devastating barrier. Unlike other species, pronghorn do not jump fences.  Rather, they will attempt to crawl under.  In the past this resulted in getting hung up in the fencing, causing injury and possibly death.  Today, however, ranchers construct fencing which allows the pronghorn to go under and continue their migratory journey [14].

The restoration of the pronghorn, a unique species, has been a marked success in the overall efforts to preserve the Great Plains.  Their comeback is proof that concerted conservation endeavors can succeed, providing inspiration for other Great Plains restoration undertakings.

End Notes:

[1] Urbigkit, Cat. 2010. Path of the Pronghorn. Boyds Mill Press. Honesdale, PA 7.

[2] Rickel, Bryce. 2005. Large Native Ungulates. Chapter 2 in USDA Forest Service Gen. Tech. Rep. RMRS-GTR-135-vol. 2. 27.

[3] US National Park Service. Pronghorn: Racers of the Great Plains.  Pronghorn: Racers on the Great Plains (U.S. National Park Service) (  Retrieved 28-Nov-2020.

[4] Rickel.

[5] Lott, Dale F. 2002. American Bison: A Natural History. University of the California Press. Berkeley, CA. 122.

[6] Schuette, Keith.  “Bring Back the Buffalo Nation—Part 3.” February 2019.

[7] Organic polymers that form key structural materials in the support tissues of vascular plants.

[8] Lott. 120-122.

[9] Rickel. 29.

[10] McHugh, Tom. 1972. The Time of the Buffalo. University of Nebraska Press. Lincoln, Nebraska. 219.

[11] Urbigkit, 8. See also National Wildlife Federation. Pronghorn. Pronghorn | National Wildlife Federation ( Retrieved 4-Dec-2020. 

[12] US National Park Service. Pronghorn: Racers of the Great Plains.  Pronghorn: Racers on the Great Plains (U.S. National Park Service) (  Retrieved 28-Nov-2020.

 [13] Rickel.

[14] Urbigkit. 32.

The Incredible Shrinking Bison

Toward the end of the 19th century the bison faced extinction by extermination.  Today, even after more than a hundred years of restoration efforts, the plains bison is faced with another threat of extinction—the accelerated warming of the Great Plains.

The Plains Bison (Photograph by Kailyn Komro, West Bend, WI.  (

Even before the immense public attention on climate change, there has been great scientific interest in climate processes and extinction events in the Earth’s natural history.    Evaluation of fossil evidence has shown an inverse correlation between warming trends and body size and mass of large mammals.  As temperatures rise, body size shrinks over large geological time scales. Along with this negative correlation a consequent, positive correlation has been established between shrinking body size and extinctions [1].  

The warming trend, which began at the end of the last Ice Age, has been accelerating in recent decades. [2].  Since the beginning of the 21st century the northern Great Plains’ average summer temperature increased by 0.8˚C while for the southern Great Plains the mean summer temperature rose by 0.4˚C with winters rising by 0.25˚C for both the southern and northern Great Plains [3]. Consequently, the IPCC (Intergovernmental Panel on Climate Change) Working Group 1 predicts a 4˚C increase in global temperatures by 2100 over the 20th century—a period of 100 years.   This rate of temperature change is much greater than for the Bolling-Allerod period [4]—a warming period 14,700 to 12,500 years ago with a mean temperature 6˚C cooler than that for the 20th century.

The evolutionary history of bison has shown an absolute increase of 4˚C is not unprecedented.  However, the time frame in which the bison has had to adapt needs to be considered. From the end of the Last Glacial Maximum (approx. 14,700 years ago) to the 20th century the earth warmed 6˚C. During the Last Glacial Maximum, bison mass was, on average, approximately 910 kg. (2006 lbs.). The greatest decline in body size of 26% occurred between 12,500 and 9250 years ago. Given a generation time between 3 and 10 years, the change in body size occurred in 325 to 1080 generations, producing an average rate of change of 0.2 to 0.7 kg per generation.   If the current warming trend continues as predicted for the 21st century, bison body mass will likely decline from 665kg (current average body mass) to 357kg.  It is unclear whether bison can adapt their body size to a 4˚C temperature increase within 10 generations [5].

Changes in body size and mass of animals have long been used to indicate large-scale environmental processes over geological time scales, and have become predictors of extinction risk in mammals [6].  In regard to bison B. antiquus and B. occidentalis, these species did go extinct, but through phenotypic [7] and morphologic [8] adaptation to changing climatic conditions, they evolved into what is known today as the North American bison (Bison bison) which has existed throughout the Holocene epoch-the current geological epoch. The importance of body size in dictating extinction proneness is likely due to the fundamental association between size and other key life history traits such as fecundity, longevity, mating system, trophic level (step in a nutritive series, or food chain), dispersal ability and energetic requirements [9].

Bison Size Comparison (from

Fossil bison shrank with global warming probably because large-bodied grazers are disadvantaged both by heat dissipation and by the phenological [10] shifts in plant quality and abundance in warming conditions [11].  Impacts of climate change, then, are two-fold: 1) direct effects of temperature on the animal, demanding energy to compensate for heat, and 2) indirect effects of temperature on the animal’s food supply [12].

Maximum body size of endotherms–an animal that is dependent on or capable of the internal generation of heat; a warm-blooded animal—depends on optimal maintenance for the efficient production of tissues.  This is especially true in seasonal environments when food availability and environmental demands constrain the annual windows for growth.   Optimal maintenance is dependent on thermal loads (amount of heat energy).  High thermal loads increase cost of body maintenance to balance internal and external loads through thermoregulation, which reduces energy for growth.

Thermoregulation is the mechanism by which heat balance is achieved.  It affects the use of energy, water and nutrients such as electrolytes and organic nitrogen which affect resting and foraging behaviors. Thermoregulatory processes usually increase energy use by increasing heart rate and blood flow.  In hot weather thermoregulation increases the flow of body water because water is used for evaporative cooling (e.g., panting, perspiration).  In cold weather thermoregulation generates body heat through such efforts as shivering, increased metabolic heat production, and muscular activity in an effort to conserve core body heat through control of blood flow to the periphery [13].

The negative climate-body size correlation, then, reinforce feedbacks that may increase extinction rates [14].  Both excessive heat (> 40˚C) and excessive cold (< -30˚C) directly increase demands for energy, water and nutrients because thermoregulation outputs increase, whereas indirect effects of rising temperature decrease forage quantity and quality—ultimately affecting the supply of energy, water and nutrients [15].  Smaller body size, then, is more efficient in regulating increased thermal loads due to rising temperatures.

Conceptual model of the direct and indirect effects of elevated ambient temperature on body size of Bison bison from Martin, et. al., 2018.

In regard to food supply, climatic warming tends to exacerbate nutritional stress and reduce weight gain in large mammalian herbivores by reducing plant nutritional quality.  Warming trends have the potential to not only reduce the nutritional quality of plant species, but also by decreasing the relative abundance of nutritionally critical plant species.  For the North American plains bison this is likely to result in an increase protein stress, reducing bison growth and reproduction [16].

Compounding the issue of decreased nutritional quality of grasses, the warming trends have resulted in an increase of droughts in the Great Plains.  The lack of water availability reduces the availability of critical plants necessary for bison growth.  Consequently, droughts cause declines in the number and body size of bison [17].

One of the driving factors in the rising temperatures may be the increasing CO2 concentrations which reduce plant protein concentrations in grasslands [18].  Increasing atmospheric CO2 concentrations have been causing Nitrogen to become progressively more limiting to ecosystem productivity.  Nitrogen is a crucial element for many structures and metabolic processes in plants. Plants are required to manufacture the complex molecules by use of minerals from the soil that contain nitrogen such as nitrate ions. Plants too, like animals, need some important macro and micro nutrient elements including nitrogen, oxygen, hydrogen and carbon to keep them healthy. The wellness of plant parts (leaves, roots, trunks, etc.) depends on the availability of essential nutrients like nitrogen to enhance the plant’s biological processes including growth, absorption, transportation, and excretion [19].

Science has offered information and theories concerning the effect of warming trends on the size and survival of bison.  The question for us is: how do we respond?   The Great Plains are predicted to warm, resulting in longer, hotter summers accompanied by more severe droughts.   The anticipated warming and drying along the Great Plains will shift the distribution and protein efficacy of vegetation types by mid-and-late century, altering the supply of digestible energy and digestible nitrogen to bison, native wildlife and domestic livestock [20].  Bison are very good at adapting to shifts in environmental processes given the rates of change in the past.  But with the acceleration of warming rates, their adaptive ability comes into question.

With decreasing body mass life history traits that are dependent on body mass will also shift. Age of maturity, reproduction rates and growth rates will be reduced.  Preliminary data already indicate a decrease in the life span of female bison, reducing reproductive rates [21].

In response, there are ways to mitigate the observed effects of the climate shifts on bison according to Dr. Jeff Martin— an integrative conservation ecologist.  Prescribed burns to the land to boost available energy and protein in grasses are one example.   More generally work is needed to determine how best to create landscape heterogeneity for bison to select the best available forage [22].

To achieve such a goal, management questions arise.  For instance, bison diet remains poorly understood which limits the ability to determine the plant species most critical, and consequently prohibits a full understanding of the required management of dietary needs.  Plains bison are considered strict grazers.  This implies they primarily consume grasses and grass-like flowering plants—such as sedges—as opposed to browsing on forbs, shrubs or trees (woody species).  Being strict grazers would suggest that climatic warming may reduce bison performance by altering the productivity and nutritional quality of different grass species. However, earlier analyses may have overemphasized the contribution of grasses and underemphasized the amount of herbaceous and woody species in their diet.  Recent studies have suggested that bison utilize eudicot species to some degree.  If eudicot species constitute a critical component of bison diet, then managers will need to take into account the relative abundance of these and their nutritional quality when considering mitigation strategies [23].

Bison have been wonderfully adaptive to environmental and climatic changes over the course of their history. Until recent times, though, they have had great expanses of time to acclimate to new conditions.  The recent accelerated warming trends have placed another hurdle in their evolutionary path—a shortened time frame in which the species has to respond.  It is unclear whether the species will be able to offset the induced biological stress with a shift in body mass in the allotted time. It is highly unlikely the climate shift underway can be halted or reversed.  Mitigation efforts, then, need to focus on land management to provide the requisite forage.  This will, however, require additional studies and the implementation of known effective practices. 

Simply restoring bison numbers is not enough. To ensure the survival of this keystone species, land and vegetation management practices which will mitigate the current climate effects need to be developed.  

End Notes:

[1] Isaac, Joanne L. 22-May-2008. Effects of climate change on life history: Implications for extinction risk in mammals.  Endangered Species Research. Vol. 7:115-123, 2009.

[2] See IPCC-AR5, 2013; USGCRP, 2018.

[3] Martin, Jeff M. Perry S. Barboza. 06-Dec- 2019. Decadal heat and drought drive body size of North American bison (Bison bison) along the Great Plains. Wiley. Retrieved 19 Oct 2020.

[4] The transition of from the last Glacial Maximum (12,500 years ago) to the Holocene

[5] Martin, Jeff M., Jim I. Mead., & Perry S. Barboza. 10-Apr-2018. Bison body size and climate change. Wiley.

[6] Isaac.

[7] Pertaining to the appearance of an organism resulting from the interaction of the genotype and the environment—Webster’s

[8] Pertaining to the form and structure of an organism considered as a whole—Webster’s

[9] Isaac

[10] Pertaining to the influence of climate on the recurrence of annual phenomena of animal and plant life—Webster’s Unabridged Dictionary of the English Language. 2001. Random House.

[11] Craine, J. M., Towne, E. G., Joern, A., & Hamilton, R. G. (2009). Consequences of climate variability for the performance of bison in tallgrass prairie. Global Change Biology15(3), 772– 779.  See also

Martin, Jeff M., & Perry S. Barboza. 06-Dec-2019. Decadal heat and drought drive body size of North American bison (Bison bison) along the Great Plains. Wiley.

[12] Martin, Jeff M., Jim I. Mead., & Perry S. Barboza. 10-Apr-2018. Bison body size and climate change. Wiley.

[13] Martin, Jeff M. Perry S. Barboza. 08-Jul-2020. Thermal biology and growth of bison (Bison bison) along the Great Plains: examining four theories of endotherm body size. ESA Journals.

[14] Isaac.

[15] Martin 2019.

[16] Craine, Joseph M. E. Gene Towne, Mary Miller & Noah Fierar. 16-Nov-2015. Climatic warming and the future of bison as grazers. Nature.

[17] Craine, J. M., Nippert, J. B., Elmore, A. J., Skibbe, A. M., Hutchinson, S. L., & Brunsell, N. A. (2012). Timing of climate variability and grassland productivity. Proceedings of the National Academy of Sciences109(9), 3401– 3405. Retrieved 19 Oct 2020. Also Martin, Jeff M., Perry S. Barboza. 06-Dec-2019.

[18] McKauchlan, K.K., Ferguson, C.J., I. E. Ocheltree, T. W. & Craine, J.M. 2010. Thirteen decades of foliar isotopes indicate declining nitrogen availability in central North American grasslands. New Phytol, 187, 1135-1145.

[19] Tajir, Amir. 02-Nov-2016. What’s the function of Nitrogen (N) in plants? Greenway Biotech.  Retrieved 19-Oct-2020.

[20] Martin, 2020.

[21] Martin,, 2019.

[22] Kobilinsky, D. 16-Dec-2019. Droughts and high temperatures are shrinking bison. The Wildlife Society.  See also Jeff Martin’s website

[23] Craine, et al., 2015.

A Town of Two Tails: Apologies to Dickens

In the midst of the prairie the taller grass gives way to a small expanse of cropped grass interrupted by numerous dirt mounds. Grazing this neatly trimmed lawn, a herd of buffalo watch our approach unconcerned.  However, looking closely, tiny sentinels raise up on their rear haunches to signal an alarm at our intrusion.  We have just come upon a prairie dog town, the residents of which have seen their best times come and go while their worst of times are upon them. This is the tale of the two most notable tailed-dwellers of the prairie dog town—the prairie dog and the American bison.

Picture from Smithsonian National Zoo & Conservation Biology Institute

                Like the buffalo the prairie dogs blanketed the Great Plains and the surrounding prairies by the hundreds of millions—with some estimates as high as 5 billion—up into the 20th century. Human intervention, though, has decimated the prairie dogs just as it did to the American bison. The conversion of the rich soil of the prairies to the “true religion” of agriculture tore up and turned over these sculptured underground dwellings.  Those who did not die from the apocalyptic loss of their habitat were hunted down and eradicated by farmers and ranchers who saw these rodents as just another destructive varmint. Prairie dog populations have also declined due to bubonic plague—an indirect human intervention—for which they have no natural immunity.  Sylvatic bacterium, the cause of bubonic plague, was brought to the North American continent by rats which sailed the Atlantic along with the European immigrants. Generally, once infected, an entire colony may be lost.  Another keystone species sacrificed to the god of Manifest Destiny.

                Prairie dogs, a seeming weakling, weigh in at about one-and-a-half pounds. Their numbers, however, more than make up for their small mass providing a significant impact to the prairie economy.  Prairie dogs live in colonies consisting of smaller family units called coteries.  The uniqueness of these rodents lies in their engineering ability to build towns. Not really a town, this unique residential area is a system of burrows engineered and excavated by these furry little rodents.  “Build,” then, is perhaps an incorrect term.  Rather they dig, excavating burrows, constructing complex systems containing sleeping quarters, nurseries, food pantries and even a cemetery of sorts.   A single colony may cover thousands of acres [1].

                Their burrows are wonderfully constructed. The genius lies in how the openings are constructed.  There are actually two openings, one at the front and one in the rear, allowing air flow.  The flow of air is regulated by mounding the excavated dirt at the front entrance.  The mound is usually a few inches—though can be as high as two feet–above the entrance.  The wind across the top of the mound is much faster than at the ground-level of the entrance since the friction caused by the ground and the grass slow the wind.  The faster wind speed at the top of the mound draws stagnant air out of the tunnels thus providing a steady flow of fresh air into the soil-level rear entrance [2]. This lowly ground squirrel utilized the wind as a renewable source long before the thought entered our magnificent brains.

Prairie Dog tunnel-housing also serve as a safe space, providing security against most predators. Too small to withstand many predators the prairie dogs use borrows to evade the horror of being dinner.  The openings, which are too small for most predators—such as foxes, coyotes and wolves—provide a convenient escape route.  However, the openings do not restrict other predators such as the prairie rattle snake or ferrets.  In the case of the prairie rattle snake the prairie dogs do not rely on their burrows for protection.  Instead they “gang-up” on the snake.  Since the snake cannot hide in the cropped grass of the prairie dog town, it is easily spotted and surrounded by the residents of the burrows, quickly turning the tables.  The hunter becomes the hunted.  The prairie dogs fling dirt in the snake’s face, by turning their backs on the predator and kicking up dirt with their hind legs.  Others may dart to the snake’s tail, biting harshly into its tail, and then dart away to escape the answering strike [3].

                Ferrets, on the other hand, are not so easily evaded. Since the ferret can easily enter the burrows—and often will seize occupancy—the prairie dog’s only hope is to out run the ferret.  The Black-Footed Ferret is the natural enemy of prairie dogs, depending almost entirely on prairie dogs for its sustenance, constituting 90% of a ferret’s diet.  With almost a 95% loss of the prairie dog’s habitat, the extermination efforts of ranchers and farmers, and introduction of bubonic plague, the prairie dog has become a threatened species, with the dependent ferret becoming an endangered species [4]. 

Black-footed Ferret

These underground architects are key, then, to the survival of other species, not just as prey, but as providers of affordable housing.  Abandoned or otherwise unoccupied burrows become shelter for prairie rattlers, burrowing owls, toads, jack rabbits, and spiders. And, as in the case of ferrets, the burrows are simply taken over.  With the decline of the prairie dogs, these species have subsequently loss habitat. 

Adept engineers these squirrelly diggers are also wise landscapers.  The prairie dogs transform the landscape around their colonies.  The surrounding grass and other plants are kept closely cropped to the ground, both for eating and for providing a clear view of potential predators.  This well-manicured yard also provides habitat for other species—for instance, birds that live in short-grass environs.

                The mounds of dirt and the cropped grass are also invitations to the largest denizens of the prairie—the bison.  Short grass is a bison’s dream diet.  The closer the blade is to the roots  the higher the percentage of protein and the lower the percentage of cellulose.  By grazing the same ground every day prairie dogs keep the grass short, inviting the bison to a culinary delight.  Closely cropped grass is a necessity to a prairie dog, but it is a treat for buffalo. 

                The bison do not just come for the grass, however.  The mounds of dirt are another attraction.  The excavated soil is perfect to fill their hair, which drives out insects and provides a coolant for hot days.  So the little chimneys of dirt erected in prairie dog town are a venerable day-spa of wallowing for the behemoths of the plains. 

A bison wallowing

                The relationship between prairie dogs and bison is not one-sided, though.  Bison also bring something to the table, or rather, leave something behind.  This other keystone species provide re-purposed grass.  That is, grass processed into fertilizer.   The longer the bison hang around the more they spread their contribution, and the greener the grass becomes.  Buffalo chips are gifts that keep on giving [5].

                Finally, bison make prairie dog towns possible.  Everywhere except in the western short-grass regions, prairie dogs depend on bison grazing to provide short enough grass for the prairie dogs to establish residence there.  This ground squirrel will not live in tall grass since it is less nutritious and hides predators [6].

                 The ending of the tale of the town of two tails is still being written.  The recognition of the prairie dog and the American bison as key to the survival of the Great Plains and the prairies has sparked concerted efforts to restore this excavating rodent and the grass-processing behemoth of these ecosystems.  As prairie dog habitat recovers, a return of other species is seen.  Homes become available for the burrowing owl and the prairie rattler.  Meals become available for the black-footed ferret enabling a retreat from extinction.  Bird populations of short-grass environs recover.  Where the buffalo roam and the prairie dog digs, the Great Plains see a renaissance.     

End Notes:

[1]  Boyce, Andy and Andrew Dreelin. Jul 02, 2020. Ecologists Dig Prairie Dogs and So Should You. Smithsonian National Zoo and Conservation Biology Institute. Retrieved 22 Aug 2020. .

[2] Lott, Dale F. 2003. American Bison: A Natural History. University of California Press. Berkeley. 127-128.

[3] Lott. 131.

[4] Anderson, Chamois. Nov. 14, 2019. Ferrets and Prairie Dogs and Bison,  Oh My! Retrieved 30-Aug-2020.,birds%20such%20as%20mountain%20plover%20and%20burrowing%20owl.

[5] Lott. 128. See also the posting dated 26 April 2019, “Dung Cakes and Feces Pie: Yum!”

[6] Lott. 128.

Good Elk Woman

In 1898 a Scottish immigrant, James “Scotty” Philip, purchased a small herd of buffalo from D.F. “Dug” Carlin who was the estate administrator of his brother-in-law, Peter Dupree (Dupuis).  Under Philip’s management the herd grew to more than eighty.  Unlike other ranchers of his day, who sought to interbreed buffalo with cattle seeking financial gain from the venture, Philip did not like mixed blood bison.  Consequently, his efforts were dedicated to weeding out the mixed-blood and establishing a pure-blood herd.

                Scotty died in 1911, leaving the herd to his sons, Stanley and Roderick.  By that time the herd had numbered around 400, but financial problems developed and the sons had to sell off 36 bison—six bulls, eighteen cows and twelve calves.  They sold the buffalo to the state of South Dakota in 1914.  In that same year the South Dakota legislature had designated 60,000 acres in Custer County as a state game preserve.  The 36 bison from the Philips’ herd became the nucleus of the herd now found in Custer State Park today [1].

                James “Scotty” Philip has been given much credited in the preservation efforts of bison, and rightly so.  Raising a sizable pure-blood herd from a small mixed-blood one, and from which came the starter herd for one of the biggest herds in the United States, is to be lauded.  The initial preservation efforts from which this herd originated, however, were expended by Peter Dupree and his parents, Frederick and Mary Ann—also  known as Good Elk Woman.  Further, the vision and impetus to save the bison most likely came from her. 

                Frederick Dupuis (Dupre, Dupree) was a French Canadian fur trader who came to Fort Pierre, Dakota territory in 1838. Eventually, he left the fur trade and became a rancher until his death in 1898. He married a Minniconjou Lakota woman named Good Elk Woman who took the name Mary Ann Dupuis.  Good Elk Woman (Hehake-waste-win) was born in 1824 near Cherry Creek, Nebraska and was the daughter of One Iron Horn and Red Dressing [2].

Good Elk Woman with husband Frederick Dupuis and son Xavier(from Native Heritage Project-

Together they had nine children:  Xavier, Edward, Pete, Fred Jr, Maggie, Esther, Armaine, Josephine and Marcella.  Frederick and Good Elk Woman established a ranch on the north side of the Cheyenne River approximately 35 miles west of where the Cheyenne empties into the Missouri River.  The ranch hosted a camp for Native American activity with at least 50 people served supper daily [3].

                During the 60 years they shared together, the Dupuis’ witnessed the severe transformation of the Plains Indian culture, the Black Hills gold rush, and the demise of the great buffalo herds.  Under the influence of Good Elk Woman, her husband and son, Peter, embarked on an expedition to save the buffalo sometime in the early 1880s. She was not just the visionary, however.  Good Elk Woman was instrumental in attending to the camp and guiding the family. The details of the hunts involved are unclear, but the result was the Dupuis family had managed to capture a few calves and initiate a herd which consisted of 5 cows, 4 bulls and 7 mixed-blood catalo by 1888.  The catalo did not result from any intentional effort on the part of the Dupuis’s management of the herd.  Most likely, the mixed-blooded catalo resulted from the ranging of bison with cattle [4]. 

                That Good Elk Woman was the visionary and impetus for an effort to save the bison from extermination should not come as a surprise.  Being Lakota she would not have perceived her existence and fate as separate from that of the bison ranging across the Great Plains.  The Lakota’s fight to protect their homeland was a fight to protect the Buffalo people’s homeland as well.  Her people were one with the Buffalo Nation (Pte Oyate).  Her authority as matriarch in the family and her prophetic role in the salvation of the buffalo was in accord with White Buffalo Calf Woman—the spiritual mediator between the Pte Oyate and the Lakotas [5]. 

Good Elk Woman (from Native Heritage)

                Today we enjoy the Custer State Park herd—one of the largest in North America.  The credit for seeding this herd has gone primarily to James Philip with perhaps ancillary credit going to Peter Dupree.  Except for Zontek, sources focus on the contributions of Frederick and Peter Dupree and James Philip.  Good Elk Woman is only been mentioned in passing as either Peter’s mother or as Mary Ann, wife of Frederick Dupree/Dupuis [6].  Her contribution, though, is arguably,  the most significant.  The origins of what has become the Custer State Park herd emerged from the vision and inspiration of a Lakota woman—Good Elk Woman.

End Notes:

[1] Dary, David A. 1989. The Buffalo Book: The Full Saga of the American Animal. Ohio University Press. 231-232.

[2] Geni My Heritage Company. Elk Woman. Retrieved 19-Jul-2020.

[3] Zontek, Ken. 2007. Buffalo Nation: American Indian Efforts to Restore the Bison. University of Nebraska Press. 48-49.   See also Looking Back Woman—Suzanne Dupree Blog. . Retrieved 19-Jul-2020.

[4] Zontek. 50.

[5] For an account of the story of the White Buffalo Calf Woman see Walker, James R. 1991. Lakota Belief and Ritual. University of Nebraska Press. 109-112.

[6] Zontek has perhaps honored her most [Zontek. 50-51].

“Werewolf? There Wolf”[7]

The largest North American mammal has only three predators: the grey wolf, the grizzly bear, and the human being.  The First Nations hunted bison for perhaps a millennium until their replacement, the Europeans, arrived with their style of killing frenzy, driving the bison into near oblivion in the 1870s and ‘80s—ironic how the scrawniest predator became the greatest threat.  These days killing by the human denizen is restricted to commercialization and licensed hunts.  In addition, something wonderful happened in human consciousness, a great awakening.  Humans had discovered ecosystems, and how those environmental realms were integral to a human’s well-being.  Further, they discovered that the bison was a keystone species to at least one of those ecosystems.  Will miracles ever cease!  The human predator has been significantly mitigated.

 Grizzlies, the polar opposite of scrawny, have been known, according to historical accounts, to kill bison.  A grizzly taking down a bison may still occasionally occur in Alaska where bears are more numerous.  A buffalo killed by a grizzly, however, is rare.  Typically, grizzlies prey during the spring melt on thawing carcasses of bison that had died over the winter [1].

The wolf is another matter.  It is designed in body and behavior to kill hoofed animals. Though the grey wolf is small compared to the buffalo, its numbers more than compensate for size.  Wolves hunt in packs from as small as six to as large as a dozen.  Essentially, wolves are opportunists, able to capture and eat meat from mice to moose.  As such, they will follow buffalo herds until the right opportunity comes along.  Following a buffalo herd will often provide the pack’s needs without the necessity of a kill since small mammals are often flushed out by the bison’s feet.  But the wolves will watch and target the calves.  So adept are packs in taking down calves that the survival of a small herd of bison can be thrown into doubt.  

Grey Wolf

 Calves are defenseless by themselves. A cow or bull, though, can easily injure or kill a wolf.  A wolf pack may be able to kill a cow or bull in the winter when the bison is in a weakened state, however.  A calf only survives a wolf attack with an alert and aggressive mother and/or help from others; though probably not another cow.    A bull may be recruited in the defense by the mother leading the calf to the bull, or the calf, on its own, may run to the bull.  Typically, the bull will be young, too young to breed, rather than a mature bull.  The older bulls are most likely not present.  They are probably off somewhere grazing, building up energy for the rut.  The primary purpose of a mature bull is to produce as many off-spring as possible.  Natural selection, then, has favored the inattentive father so the maximum number of calves will be born.

When the pack’s hunt is successful, the killing is a gruesome affair. Cats kill large prey by suffocation or biting through the skulls of their prey.  Dogs do not have this mouth power to kill quickly.  Instead, dogs, such as wolves, chew their prey to death, literally eating the prey alive. This is difficult for one wolf to do, but not a pack.

A romantic view, held among some of the supporters of the wolf reintroduction movement, was that of a caring and adorable family life.  This is only a projection of human proclivities, however. Life among a wolf pack is not a canine version of the ideal nuclear family, in which mom and dad tenderly care for the young.  They are not cute.  The wolf-pack life is ruthless and relentlessly structured. Each member lives within a certain pecking order with an alpha male or female at the top. Attempts to reorder the pack are severely treated, even to the point of death.  Cruel despotism is perhaps a more apt description, egalitarianism does not exist.  Yes, wolves are family oriented, but the structure is about survival and reproduction with each member also having a specific function. The wolf family is also territorial, and will challenge any trespassers with pursuit or death.

The nature of the wolf evolved as a competitor to large predators such as the short-faced bear, the American lion, the American cheetah, the saber-toothed cat and the dire wolf, sharing the North American Plain.  The grey wolf was the smallest of these, and the only one to survive the Pleistocene extinction approximately 10,000 years ago.  It developed to become a prominent selection factor for diverse characteristics of large mammal fitness.  Wolves are highly sensitive to symptoms of weakness in their prey.  Victims tend to be debilitated by age, disease or accidental injuries which render them susceptible to the pack.  Thus wolves facilitate natural selection by detecting and removing the effects of deleterious genes, and removing the most virulent strains of a pathogen from a prey population [2]. 

As the grey wolf was sharpening its hunting skills over the millennia, bison were not idle, however.  Buffalo were also evolving their defensive arsenal, including cooperation, defense, escape, and synchronized birthing.  The bison herd is a “selfish herd.”  Individual animals cooperate with and use other animals to improve their own survival and reproduction odds, ensuring possibly the survival and reproduction of genetically related kind.  Bison, then, cooperate to the benefit of all in the herd. 

The primary weapons for defense are the horns and the head.  Using its powerful neck muscles a bison can hook, lift and toss an opponent.  This strategy works best in large herds.  By itself, a bison cannot challenge several wolves all at once.  For a cow and her calf, alone she is not likely to defend her calf using her head and horns, as the wolves will separate her from the calf, occupying her attention away from the calf.  In the herd, however, the bison will form a tight formation with the calves either in the midst of the herd or behind it.

Buffalo Tossing Wolf-from Sky Animals–youtube

Escape is exactly what it implies.  It is the “RUN AWAY!” strategy.   Escape involves outrunning and outlasting predators.  Bison have adapted physiologically and anatomically for this behavior.  Even new born calves are on their feet within 10 minutes and able to run within two hours of birth.   Buffalo can challenge all but the fastest horses, yet can out last them, running for many hours over dry, hard prairie ground.  There is a selfish component to escaping, though.  It’s not just about outrunning the predator.  A buffalo only needs to outrun its neighbor.  Escaping exposes the weakest individuals, those who lag due to injury, age or disease.  Predation selects against the least fit, favoring the evolution and maintenance of strength, agility, endurance and disease resistance.  The extreme form of escape is the stampede [3].

A characteristic of social ungulates such as the buffalo in facing predators is synchronous birthing, which has the dual purpose of predation evasion and optimum utilization of high quality forage for lactation.  Due to the behavior of wolves there is little flexibility in the bison gestation period, which leads to a synchronous breeding period.  Predators focused on bison calves must take time eating and digesting the hapless prey and spend time traveling to locate the moving herd.  Additionally, the number of wolves in an area may be limited by territorial behavior.  The number of calves, then, that can be killed by the pack during a short period of time is limited.  Bison reproduction has adapted to take advantage of this window of opportunity.  The larger the cow herd and the shorter the birthing period, the greater is the probability newborn calves will survive.  A cow that breeds during the peak of the rut and calves during the peak of calving, provides the calf with a greater chance of escaping predation [4]. 

Wolves not only have the effect of culling buffalo herds through food usage. The reintroduction of the grey wolf in Yellowstone has actually enhanced the growth of buffalo herds.  Since the reintroduction of wolves, elk population has declined, opening greater forage and releasing bison from interspecific competition and resulting in higher bison densities [5]. Elk are easier prey for wolves, resulting in lower elk densities and a decreased tendency for wolves to use bison as a food source.  The combination of opening more grazing opportunities, and decreasing the predation of bison has allowed for a significant growth in bison populations [6]. 

Predation, especially by wolves, has not only enabled bison population growth.  Co-evolving with the bison, predation has facilitated the natural selection.  Removing deleterious genes and virulent pathogens, the wolf has enhanced the bison’s strength, agility, endurance and mechanisms for preservation.  Just as the bison is a keystone species to the Great Plains and the surrounding prairies and forests, so the wolf is key to the health and survival of the bison.

End Notes

[1] Callenbach, Ernest. 1996. Bring Back the Buffalo! A Sustainable Future for America’s Great Plains. University of California Press. Berkley. 90.

[2] Lott, Dale A. 2002. American Bison: A Natural History. University of California Press. Berkley. 100-104.

[3] Bailey, James A. 2016. The Essence of Wildness: Lessons from Bison. Self-published by James A. Bailey. 24-25.

[4] Bailey, James A. 2013. American Plains Bison: Rewilding an Icon. Sweetgrass Books. Helena, MT. 63-66.

[5] Ripple, William J, and Painter, Luke. Effects of bison on willow and cottonwood in northern Yellowstone Park. 15-Jan-2012. Forest Ecology and Management. Vol. 264. 150-158

[6] White, P. J., and R. A. Garrott. 2005. Yellowstone’s ungulates after wolves–expectations, realizations, and predictions. Biological Conservation. 125. 141-152. See also Ripple, W. J., and R. L. Beschta. 2012. Trophic cascades in Yellowstone: The first 15 years after wolf reintroduction. Biological Conservation. 145. 205-213.

[7] A line from the movie Young Frankenstein, 1974.

Additional Resource:

Blakeslee, Nate. 2008. American Wolf: A True Story of Survival and Obsession in the West. Broadway Books. New York.

Rosalie Little Thunder—Giving Voice to the Voiceless

For the bison herd of Yellowstone the winter of 1996-97 was deadly.  Heavy snows had made it difficult to plow through to the forage underneath.  Survival meant finding other grazing land, leading the buffalo to wander down from the mountains in search of grass.  Going north out of the Park was a death sentence.  When the bison crossed the Montana State line, they were met with gunfire.  The only witness to record the atrocity was Mike Mease, videographer and environmentalist.  The video was sent to a Sicangu Lakota woman who, in response, came to Yellowstone National Park to witness the atrocity inflicted upon the buffalo nation, and offer prayers.   That winter, under the leadership of Mease and this Lakota elder, Buffalo Nations was formed (original name of the Buffalo Field Campaign), a nonprofit, grassroots coalition of Native and Non-Native environmentalists with the support of the Seventh Generation Fund, providing a permanent defense along the Yellowstone Montana border [1]. That Lakota elder was Rosalie Little Thunder. 

Rosalie Little Thunder (from Indianz)

When Rosalie prayed over the bodies of the slaughtered buffalo that winter, she was part of a cloud of witnesses who had survived to attest to senseless horrors.   She saw, however, the bison as survivors, as she was a survivor—“Just as I am a survivor of massacre, so too are the Yellowstone buffalo survivors of massacre [2].” She was a direct descendent of survivors of both the 1855 Little Thunder Massacre and the 1864 Sand Creek Massacre.  Her own grandfather had survived the 1855 massacre, saved by his mother covering him with her body when she had been struck by a bullet [3]. 

Born 18-Sep-1949 in Old He Dog Community on the lands of the Sicangu Lakota people (Rosebud Sioux Reservation) to William and Margaret (Good Shield) Little Thunder [4], Rosalie became an avid activist promoting her people, the Lakota, and her brothers and sisters of the Pte Oyate (Buffalo People/Nation).  She served on several non-profit boards including the Buffalo Field Campaign, Owe Aku  International [5], Seventh Generation Fund [6], and South Dakota Peace and Justice.  Rosalie was also an honorary member of Honor the Earth [7], Indigenous Environmental Network [8], Wolakota Foundation [9], and Brave Heart Society [10]. In addition to these, she was an active member of Kat’ela Okalakiciye—a traditional Lakota Elderly Women’s Society—and participated in the Sicangu Constitutional Convention.

As if these activities were not enough, Rosalie was an adjunct professor at Black Hills State University, American Indian Department, teaching the Lakota language and working with the Lakota Bible Translation Department. 

Central to this life dedicated to the Native way, was the well-being of the Pte Oyate, which Rosalie held dear.  She worked to protect the buffalo from the mid-1990s until her death in 2014.  The last wild, free-roaming bison is the Yellowstone herd.  To have witnessed the decimation that winter of 1996-97, must have torn her heart apart.  She did not want the last of the wild buffalo to disappear, and wanted Native peoples to have more say in the buffalo’s fate—“After I am gone, I want there to be buffalo on this Earth. Maybe the buffalo will help us be here a little bit longer. Maybe they will help us survive. [11].”  To bring attention to the killing of the Yellowstone bison and the need to protect the herd and its natural grazing grounds, Rosalie, in 1999, led a group of Lakota Sioux on a 500-mile walk from Rapid City, South Dakota to the Gardiner basin in Montana, carrying a sacred pipe.  The journey was a form of prayer for the bison and a protest against the wanton destruction of the last wild herd of the majestic animal.  In honor of Rosalie, and to keep her memory alive, the Buffalo Field Campaign has continued this prayer practice by instituting an annual Rosalie Little Thunder Walk [12].

Such heinous acts that have been inflicted on the Buffalo Nation can overwhelm and numb a person into a silent resignation. But atrocities not heard breed more atrocities.  A voice must be given to these acts of cruelty and destruction to break the silence and prevent a numbed acceptance.  Rosalie Little Thunder was such a voice.  Even though she has passed, her spirit and voice continue speaking.  Many others, including the Buffalo Field Campaign and the organizations mentioned above, carry her spirit in their hearts and echo her voice through their words and actions.  By offering us an alternative reality to a culture of death, she was truly prophetic.

End Notes:

[1] Buffalo Field Campaign, History.  Retrieved 06-Apr-2020. Also see Basile, Tracy. Unbound Project. 16-Jul-2019. Retrieved 06-Apr-2020.

[2] Rosalie Little Thunder in Rethinking Columbus, which was banned by Tucson Public Schools.

[3] Brister, Daniel. 2013. In the Presence of Buffalo. West Winds Press. Portland, Oregon. 36-37.

[4] Rosalie Little Thunder obituary.  Osheim & Schmidt Funeral Home.  Rapid City, South Dakota.

[5] Owe Aku International is an organization dedicated to protecting our water sources against the effects of oil pipelines and tarsand.  Visit their website at

[6] Seventh Generation Fund for Indigenous Peoples is dedicated to providing support to grassroots Native communities’ projects.  Visit their website at .

[7] Honor the Earth’s mission is to “…create awareness and support for Native environmental issues and to develop needed financial and political resources for the survival of sustainable Native communities.”  Visit their website at .

[8] Indigenous Environment Network “…was formed by grassroots Indigenous peoples and individuals to address environmental and economic justice issues…[including] building the capacity of Indigenous communities and tribal governments to develop mechanisms to protect our sacred sites, land, water, air, natural resources, health of both our people and all living things, and to build economically sustainable communities.”  Visit their website at .

[9] Wolakota Foundation “…is a grassroots non-profit organization emerging from the needs of traditional Lakota (Dakota/Nakota) people to maintain their cultural and spiritual lifeways for the sake of future generations.”  Visit their website at .

[10] Brave Heart Society, formed by a community of grandmothers from the Yankton Reservation of South Dakota, works for the revival of a traditional cultural society for women.  Visit their website at .

[11] Baisle.

 [12] Third Annual Rosalie Little Thunder Walk. Buffalo Field Campaign. .  Retrieved 07-Apr-2020.

William T. Hornaday: From Preserver of the Lifelike to Preserver of Life

In May of 1886 Miles City, Montana was visited by a small expedition from the Smithsonian.  Led by the chief taxidermist of the Institution, William T. Hornaday, the group was in search of the last remaining buffalo.  The impetus for the venture arose out of alarm over the condition of the current buffalo specimens at the museum.  The museum had a very poor assortment, consisting of one mounted specimen, a couple of mounted heads, two skeletons and assorted fragmentary skulls.  After Hornaday brought this sad state to the attention of Spencer F. Baird, secretary of the museum, an expedition was quickly arranged [1].  The venture marked the beginning of the transition from taxidermist to restorer for Hornaday.

William T. Hornaday

William Temple Hornaday, born in Avon, Indiana in December of 1854, was educated at Oskaloosa College, Iowa State Agricultural College (today known as Iowa State University).  He married Josephine Chamberlain in 1879 remaining married for 58 years until his death in 1937.  Together they had a daughter, Helen [2].    

After graduating in 1873, Hornaday was hired by Ward’s Natural Science Establishment of Rochester, New York where he worked as a taxidermist.  He was only in Ward’s employ for a brief time when he headed off to India and Ceylon in 1877-78 and then moved on to Malaya and Borneo, collecting specimens.  This journey inspired his first publication, Two Years in the Jungle (1885) [3].  In 1882 he was appointed as chief taxidermist of the United States National Museum, the Smithsonian, a position he held until he resigned in 1890.  During that time, Two Years in the Jungle and The Last Buffalo Hunt (1886) were published [4].

In his position as chief taxidermist at the Smithsonian, he became aware of the decimation of the buffalo, which led him to inventory the Smithsonian’s collection, and to conduct a census of the remaining bison to estimate  the number of these majestic beasts still alive.  The results were alarming, prompting Hornaday to quickly notify Dr. G. Brown Goode, Hornaday’s immediate superior.  These actions promptly led to the expedition to the Musselshell River region of Montana—a region still occupied at that time by the Crow, Paiute, and Blackfoot—to collect bison specimens for the Smithsonian’s exhibit.  The irony in the decision was the Faustian bargain often faced by science—a few specimens would have to be sacrificed to preserve some vestige of a vanishing species for the sake of future generations [5]. 

The initial expedition in May of ‘86 was a failure.  When the expedition team arrived in Miles City, they were told their chances were next to nothing in finding any buffalo.  Besides the best time for buffalo hides was in November and December.  Though he expected to see evidence of the decimation of the herds, he was stunned by what he actually observed—no live buffalo, only skeletons as far as the eye could see.  He would have to return three months later to collect the specimens he needed [6].  When he returned in September, Hornaday fortunately had run into rancher Henry Phillips who reported that buffalo were still roaming around his ranch.  This time the expedition was successful.  Hornaday returned to Washington, D.C. with 24 hides, 16 skeletons and 51 skulls [7].

The impact of near-extermination was not lost on Hornaday, however.  He resolved to not only preserve the bison in museum exhibits, but also as a living herd in captivity.  His goal was to educate Americans and perhaps atone, in some way, for the atrocity that had been committed.  With this in mind Hornaday launched a plan with the Smithsonian’s Department of Living Animals to establish a breeding program to save the buffalo.  The Smithsonian acquired 6 buffalo, and from that the plan was executed. 

Hornaday’s efforts did not rest there.  He went on to advocate for a National Zoological Park for the conservation and study of wild animals sacred to the national heritage.  In 1889 this became a reality with Hornaday appointed as the Park’s head.  He soon left that position to become the founder and director of the Bronx Zoo.  It was during this time Hornaday’s work Extermination of the American Bison was published—considered to be the first important book of the conservation movement [8].  During his tenure at the Bronx Zoo, Hornaday published almost two dozen books and hundreds of articles advocating for the conservation of wildlife, stirring up public support which moved Congress and aided his efforts.  In addition, he lobbied tirelessly for protective legislation, national parks, wildlife refuges, and international treaties to conserve and protect wildlife [9]. 

The Extermination of the American Bison by William Hornaday

Hornaday was not alone putting forth ideas for preserving the buffalo.  Ernest Harold Baynes, a naturalist, presented the notion of an organization dedicated to the preservation of the bison to Hornaday.  Hornaday embraced the idea and along with Pres. Theodore Roosevelt cofounded the American Bison Society in 1905.  Just prior to the formation of the Society, Hornaday offered, on behalf of the New York Zoological Park, to give a small number of buffalo to the federal government if the government agreed to start a herd on the National Wichita Forest Reserve in Oklahoma.  Then once the American Bison Society was established, work was initiated to create another reserve.  The Flathead Indian Reservation in western Montana was proposed.  Within two years Congress had purchased the necessary land and by 1909 the National Bison Range had been established, being populated with bison purchased by the American Bison Society with a few donated by Mrs. Alicia Conrad of Kalispell, Montana and rancher Charles Goodnight of Texas.

Bison on the National Bison Range in Montana—picture from the US Fish and Wildlife Services

The establishment of the herds on the National Wichita Forest Reserve and the National Bison Range marked the beginning of serious efforts by the federal government to preserve the American Bison.  The Society, though, continued working to establish other reserves.  In 1913 the Society helped create a herd on the Fort Niobrara Reservation in Nebraska, and a few months later, a herd on the Wind Cave National Game Reserve in the Black Hills of South Dakota.  The last herd the Society helped establish was near Ashville, North Carolina in the Appalachians, but this herd did not prosper and eventually died out.  The Society continued to be active into 1930s primarily involved in educational efforts, and unfortunately, it, too, quietly died out by 1940.  But the original mission set out by Hornaday, Roosevelt, Baynes and others was achieved [10]. 

Always a lover of wildlife and dedicated to conservation, William T. Hornaday was a critical player in the preservation of the American Bison.  His singular vision of establishing herds on reserves was instrumental in averting the near-extinction of the majestic creature that once blanketed the Great Plains and the Prairies.  A proven crusader for wildlife, Dr. William T. Hornaday died in 1937 at the age of 82 in Stamford, Connecticut.

End Notes:

[1] Dary, David. 1989. The Buffalo Book: The Full Saga of the American Animal. [Swallow Press/Ohio University Press]. 198.

[2] Betchel, Stefan. Mr. Hornaday’s War: How a Victorian Zookeeper Waged a Lonely Crusade for Wildlife That Changed the World. 2012. Beacon Press. 3-10.

[3] William T. Hornaday.  Wikipedia.  Retrieved 16 March 2020.

[4] Betchel.

[5] Betchel.

[6] Kurn, Richard. American Bison: A Story of Near Extinction and Conservation. July 26, 2017. The Great Courses Daily.  Retrieved 6 March 2020.

[7] Dary. 199.

[8] Kurn.

[9] William T. Hornaday. Portraits and Museum Notes. The American Museum Journal. 15 (5): 202, 260. May 1915.  American Natural History Museum Digital Library.  .  Retrieved 22 March 2020.

[10] Dary.  234-240.