WILD HORSE AND BURRO DESCRIPTIVE FACT SHEET EXPLAINING THEIR
REAL PLACE IN NORTH AMERICA with references (January 26, 2011)
By Craig C. Downer, Wildlife Ecologist, P.O. Box 456, Minden, NV 89423-0456
ccdowner@yahoo.com
1. Origin: The entire horse family Equidae, including the three major branches:
zebras, asses, and caballine horses, have their origin and long-standing evolution
in North America. This includes the many branches and side branches over the
past 60-million years with no significant absence up to the present. The genus
Equus, including the modern horse Equus caballus, originated upon this
continent, the latter nearly two million years ago. The burro also has its roots in
North America and some paleontologists consider it to be the same species that
originally migrated over the Bering Straits from North America to Asia and
thence to Central Asia and Africa.
2. Equids’ Ecological Contribution: Given the fact that equids have played such a
major role in North America for so long a time, they have developed many
mutualistic relationships with the plants and animals upon which they depend.
The reason is simple: members of the horse family are a different type of
herbivore from the prevalent ruminants in North America, be they cattle, bison,
sheep, or the several members of the deer family Cervidae. Unlike these
mammalian ruminant digesters, equids are post-gastric, or caecal, digesters, who
do not decompose their plant food nearly as much as does a ruminant. Because of
this, equids are great fertilizers of the soil wherever they roam and spread their
droppings. And for the same reason, equids also disperse many more intact seeds
of a greater variety of species when compared with ruminant herbivores. Given
the wide-spread and frequent movements of equids, this seed dispersal is very
broad for a given horse or band of horses covering hundreds, even thousands of
square miles. In other words, there is an augmenting of natural seed banks
because of them. Another important factor here concerns the bolstering of the
food chain or web that incurs due to the input of nutrient-rich droppings. These
feed anyone from tiny beetles and microorganisms to birds, lizards, rodents, and
larger predators such as bobcat that feed on the latter. Our challenge as humans is
to learn to appreciate a wild-horse/burro-containing ecosystem and to grant it
sufficient protection in terms of habitat space and generational time so that it can
establish its own internal harmony. This is bound to ensue judging from all the
amazing past evolutionary history on our planet – but we must allow it to do so,
and we must learn to be a part of this wonderful inter-species harmony by living
in a non-damaging way with it and allowing it the freedom to establish itself. The
benefits of this just wild-equid-containing ecosystem would help restore the living
Earth in so many known and yet-to-be-discovered ways.
3. Wild Horse and Burro Tours: It has been shown time and time again that many
people both in America and abroad greatly enjoy observing wild horses and
burros who are free-living in their natural habitat. Successful eco-tours have been
mounted in several states throughout the West and proven themselves profitable.
If these equid ecotours were to be promoted in a way that is sensitive to the wild
horses and burros and the ecosystem they inhabit, a great mutual benefit could
result between humans and equids, uplifting to both. But these tours should be
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rest-rotated among a great variety of herds so as not to overwhelm any one herd
or its habitat. This could be accomplished by proper organization among the tour
operators in conjunction with conscientious oversight from government agencies.
It is doable and would be a great boon to all involved.
4. Equids as Moderators of Global Warming: Along with zebras, horses and burros
are perfect species to reduce dry flammable vegetation that is becoming
increasingly prevalent throughout the West due to Global Warming. Again, their
post-gastric digestive system makes them perfect for this role. This is due to their
not having to as thoroughly decompose the vegetation they consume as a
ruminant would. Hence this drier food would not require so much metabolic
energy as a ruminant cow for example – who would literally burn itself up trying
to subsist on this dry diet. Also, the semi-nomadic nature of the wide-ranging
horses and burros lends itself well to this role. They practice a natural rest
rotation where fences do not impede this -- fences that are all too prevalent and
really illegal within their legal herd areas on BLM and USFS lands. Again the
question is whether we people will allow the equids to realize their very healing
life style by removing fences and other impediments to their natural freedom. We
should learn to appreciate the benign process that is taking place with the
restoration of wild horses and burros within their very cradle of evolution: North
America. – Remember too that through their droppings, the wild equids will
recycle the dry vegetation they consume converting it into vital humus for the
rebuilding of soils. This will redound in more moisture-retaining soils, higher
water tables, restored watersheds, and more nutrient-rich soils capable of fostering
a greater abundance and diversity of plant and animal species, naturally balanced
and healing to the living Earth as a whole. Then our human challenge will be a
most welcome one: to discover a way to live harmoniously with this wild-horseor-burro-containing ecosystem, even if this is to be just as a visitor, an appreciator
of such. –Surely we can do this with God’s help. This is the right way to proceed.
Bibliography with notes
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This elaborate study shows how another equid, the Zebra, complements a variety of
grazers, including the Thompson’s Gazelle and the Wildebeest by eating coarser, drier
grasses. The removal of these allows other types of vegetation to grow. The study
describes the movement patterns of the zebras in relation to the other herbivores and how
this relates to an elaborate natural system that has evolved over thousands of generations
in Africa. Undoubtedly, a similar system existed between equids in North America and
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other sympatric species of herbivores. Many of the observations of this elegant study
apply to the wild horses and burros in North America, including the West, for the horse,
far from being a misfit, restores and enhances the native North American ecosystem, and
given the right setting, much the same can be said of the burro.
Benton, Michael. 1991. The Rise of the Mammals. Crescent Books, New York. P. 135.
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with some of the key players.
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Dallas, Peter. 1987. Wild Horses of the Nevada Desert. A film by Peter Dallas of
Sacramento, CA, produced for Nevada Commission for the Preservation of Wild Horses.
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Downer, Craig C. 1977. Wild Horses: Living Symbols of Freedom. Western Printers
and Publishers, Sparks, NV. 73 pages. Illustrated account by author based on studies
undertaken while earning M.S. at University of Nevada-Reno and including many first
hand observations in the Pine Nut Range of western Nevada. Photos by author. Later
reprinted in 2007 with some new digital photos of wild horses from Western Nevada.
Forward by Wild Horse Annie, i.e. Velma Bronn Johnston.
Downer, Craig C. 2005 (Dec.). Wild and Free-Roaming Horses and Burros of North
America: Factual and Sensitive Statement – How They Help the Ecosystem. Natural
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Downer, Craig C. 2008 (July-August)). Conservationist with a Heart: A Brief Sketch of
the True Lady Wild Horse Annie, Velma B. Johnston. Natural Horse 10(4):22-24. Also
presented at convention of Nevada Women’s History Project in Carson City, Nevada and
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Fazio, Patricia Mabee (Ph.D.). 1995. The Fight to Save a Memory: Creation of the Pryor
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1971.” Ph.D. Dissertation. Texas A & M University. Excellent and thorough-going
treatment of the wild horse preservation/restoration movement, factually based.
Ferguson, D. & N. Ferguson. 1983. Sacred Cows at the Public Trough. Maverick
Publications, Bend, Oregon. 250 pages. Excellent documentation and discussion of
livestock monopolization of public lands.
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General Accounting Office. 1990 (August). Rangeland Management: Improvements
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Receipts Vary Depending on the Agency and the Purpose of the Fee Charged. Document
# GAO-05-869. Washington, D.C.
Grzimek, Bernhard. 2004. Grizimek’s Animal Life Encyclopedia – 2nd Ed. See
sections on horse feeding ecology on pages 141, 220, 228 & surrounding pages.
To quote from page 141: “The ruminant is faced with being more selective in its feeding.
In contrast, the hindgut fermentors, such as some perissodactyls (e.g. modern horses) are
able to increase the rate that food passes through their gut, so they extract only the most
readily digestible fraction of the food and excrete the indigestible material. As a result,
although they must feed almost continuously, they can be much less selective in what
they eat. This allows horses to survive on poorer-quality food than artiodactyls are able
to do” [i.e. dry flammable vegetation such as cheat grass].
To quote from page 228, Feeding Ecology and Diet: “Equids are primarily grazers and
have dental adaptation for feeding on grasses. Their high-crowned molars with complex
ridges allow them to effectively grind grasses with higher-fiber content. Though
individuals will select the most nutritious and low-fiber forage, they can process
senescent [dying] and higher fiber grasses. Equids also have a single stomach and
hindgut fermentation. This allows them to digest and assimilate larger amounts of forage
during a 24-hour period. By contrast, ruminants with a four-chambered stomach are
limited in the volume of forage that can be digested in a 24-hour period. Equids are more
effective in assimilating forage and can tolerate and survive on a greater breadth of diet in
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High Plains Films. 2001. El Caballo: Wild Horses of North America. The Fund for
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Horsetalk. 2009 (April 5). http://www.horsetalk.co.nz/news/2009/08/054.shtml News
item regarding BLM’s obstinant stance on zeroing out of West Douglas wild horse herd.
Hudak, Mike. 2008. Western Turf Wars: The Politics of Public Lands Ranching. A very
timely expose of the livestock industry’s monopoly of the U.S. public lands.
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seasons of the year.
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capable of thriving in what would be to other herbivores very marginal ecosystems, such
as the desert valleys and ranges of Nevada, especially compared with ruminants evolved
in moister, more lush and verdant biomes, such as Hereford or Black Angus cattle.
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Kent News. ? date. www.kentnews.co.uk/kent-news/Rare-wildlife-helped-by-wild-horses
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America’s last wild horses by award winning producer George Knapp. Aired on CBS
Channel 8 TV, Las Vegas. Recognized by Edward R. Murrow top award for region.
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M
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through the stomach, so the passage rate of vegetation is not as limited as it is in the
ruminant grazers, enabling equids to consume large quantities of low-quality forage and
to sustain themselves on more marginal habitats and on diets of lower quality than
ruminants. Even when vegetation grows rapidly, equids forage for about 60% of the day
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out Chapter 12: Population Dynamics, Behavioral Ecology, and “Paleoethology” and also
page 112.
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population numbers, etc.
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harm and death incurred due to helicopter chase roundups of wild horses by a
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mountains and adjacent valleys they inhabit.
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holdover that enriches ranchers and degrades the land. San Jose Mercury News, San
Jose, California. Another excellent expose with many facts and figures.
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Ryden, Hope. 1999. America’s Last Wild Horses. 30th Anniversary Edition. The Lyons
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helped pass the Wild Horse Act in 1971. A must read.
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Trippett, Frank. 1974. The First Horsemen. IN The Emergence of Man series. Time-Life
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University of Wyoming. 1979. Proceedings of the Symposium on the Ecology and
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Webpages, various. References for Chapter IV regarding bills, etc., concerning wild
horses: www.thecloudfoundation.org, www.wildhorsespirit.com,
www.wildhorsepreservation.com, www.wildmustangcoalition.org,
www.wildhorsesummit.org, www.fund4horses.org, www.naturalhorsesense.com,
www.americanherds.com, http://homepage.mac.com/john.brian ,
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Subsidized Destruction of the American West. Island Press, Washington, D.C. 346 pp.
Excellent documentation and illustrations proving livestock’s very damaging effect.
Wynne-Tyson, Jon. 1989. The Extended Circle: A Commonplace Book of Animal
Rights. Paragon House, New York. 436 pages.
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Zimov, S.A. 2005. Pleistocene park: return of the mammoths’ ecosystem. Science
308:796-98. Indicates great importance of horses to establishing and maintaining tundra
grassland that has a cooling effect on the Earth’s atmosphere. Their reintroduction in
parts of Siberia is proposed as a way of preventing further Global Warming, especially
given accelerating melting of the permafrost. This would apply to northern North
America.
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