August 6, 2026
Editor’s Note: This essay was written by wildlife ecologist Craig C. Downer in response to a recent blog that purported to review his earlier essay on Salt River wild horses. Rather than engage in a point-by-point rebuttal, Downer addresses broader questions of scientific accuracy, site-specific evidence, and the proper role of science in wildlife management.
BY: CRAIG C. DOWNER, WILDLIFE ECOLOGIST AND AUTHOR
A recent blog post prompted me to reflect on how the scientific literature surrounding wild horses is sometimes presented to the public.
Unfortunately, the misrepresentation begins before any discussion of science even starts. The blog attributes to me a title I did not write, replacing the actual title of my essay, “Protecting the Salt River Wild Horses is an Investment in Arizona’s Natural Heritage and Eco-Tourism,” with a far more inflammatory title about slaughter and imprisonment.
It then claims that I advocated reducing the current herd target of approximately 125 horses to an even smaller number. I made no such argument. My concern was precisely the opposite: whether reducing the existing Salt River herd to a proposed target of approximately 125 would preserve a genetically healthy, socially intact and naturally functioning wild population.
The blog also repeatedly portrays me as having declared that a herd of 125 horses is definitively genetically nonviable. What I actually wrote was that, in my professional opinion, 125 would be insufficient, that such an artificially low population could interfere with genetic diversity, and that a herd reduced too far might become dependent upon continuing human intervention. I also expressly stated that no single number can determine whether a population is sustainable.
That is not a contradiction. It is the reason I called for an independent, site-specific scientific review before horses are removed.
The critique faults me for not providing the genetic analysis, population viability assessment, habitat study, and economic evaluation that I specifically urged Arizona officials to commission and disclose. My essay was not presented as a completed population viability study. It was a warning against adopting a predetermined number before that necessary work has been performed.
Scientific discussion must begin by accurately representing the position being examined. Substituting a different title, reversing my population argument, and refuting conclusions I did not state creates a straw man, not a scientific review.
Such misrepresentations do not help wild horses. They harm them by confusing the public, polarizing the debate, and diverting attention from the scientific questions that must be answered. When inaccurate claims are presented as scientific conclusions, they can be used to justify management decisions that may have lasting consequences for the herd.
The reference list presents another concern. The number of citations attached to an argument does not establish its validity. A citation is useful only when it is relevant to the question being examined and supports the claim for which it is offered. Most of the references cited were not specific to the Salt River herd, its habitat, or the proposed population target. General studies involving different landscapes, herd conditions and management circumstances do not substitute for site-specific evidence.
Several references in the blog concern free-roaming horses across broad western rangelands, cheatgrass dispersal in western Colorado, generalized questions of native status, conservation genetics at the species level, and management conditions unlike those along the Lower Salt River. Such research may contribute to a broader discussion, but it cannot substitute for evidence about this herd, this habitat, and this proposed herd reduction.
General findings about how horses can affect vegetation when present in excessive numbers do not tell us whether the Salt River horses are presently excessive, whether they are the principal cause of habitat conditions, or whether approximately 125 is an ecologically and genetically defensible target.
The blog cites a 2019 estimate suggesting that naturally available forage along a narrowly defined portion of the Lower Salt River might support approximately 20 horses. It also cites a 2025 native plant assessment. Yet the blog itself concedes that the assessment does not provide a maximum or recommended population size for the Salt River herd. It nevertheless declares that the assessment disproves the proposition that the herd can remain naturally healthy and self-sustaining.
The blog reads conclusions into the assessment that the assessment itself does not support.
A forage estimate is highly dependent upon the geographic boundaries selected, the season and drought conditions measured, the vegetation included or excluded, access to adjacent habitat, supplemental feeding, water availability and the distribution of horses across the landscape. It cannot be transformed into a defensible long-term herd target without examining those variables openly and comprehensively.
The blog also says that I minimized forage capacity. In fact, I wrote that an appropriate herd size must account for habitat, water, forage, migration, reproduction, mortality, predation and opportunities for genetic exchange. I proposed reserve design precisely because managers should begin by evaluating the amount, quality, and connectivity of habitat necessary to sustain the population rather than starting with a predetermined number and working backward to justify it.
Similarly, I did not claim that every ecological effect of horses is positive. I expressly wrote that every species affects its habitat and that any animal population can damage the land when confined in excessive numbers, restricted to an inadequate area or denied sufficient water and forage.
My argument was that the effects of the Salt River horses should be measured objectively and compared with livestock grazing, drought, recreation, development, water diversion, vehicle traffic and other pressures affecting the same ecosystem. On this point, the blog ultimately acknowledges that I was correct.
The same pattern appears in its discussion of tourism. I did not claim to have completed an economic impact study. I argued that the herd’s recreational, cultural, educational, and economic value should be evaluated before an irreversible reduction occurs. Criticizing the absence of such a study reinforces my request that one be conducted. It does not refute the demonstrated fact that people travel to the Lower Salt River specifically to observe and photograph these horses.
A scientifically responsible review would distinguish between what is known, what remains uncertain, and what research is still needed. It would not transform qualified concerns into categorical declarations, rely on irrelevant or generalized references as substitutes for site-specific evidence, or criticize an author for requesting studies that have not yet been completed.
The future of the Salt River horses should not be decided through assumptions dressed in scientific language. It should be determined through transparent data, relevant expertise, independent review, and an honest examination of all pressures affecting the ecosystem.
Science should not fear scrutiny. It should welcome it.
I encourage readers to examine my original essay alongside the blog response and determine for themselves whether my positions were represented accurately and whether the cited references truly support the conclusions drawn about the Salt River herd.
The future of the Salt River wild horses will not be secured by the loudest voices, the longest bibliographies, or the most confidently stated assumptions. It will be secured by scientific integrity, transparent evidence, and the courage to follow the facts wherever they lead.
About the Author
Craig C. Downer is a wildlife ecologist, author, and longtime advocate for the conservation of wild horses, wild burros, and other free-living wildlife. For more than four decades, he has conducted field research involving wild equids and grazing mammals in North and South America, with an emphasis on ecology, behavior, habitat, population sustainability and conservation biology.
Downer earned a Bachelor of Arts degree in biology, with an emphasis in ecology, from the University of California, Berkeley, and a Master of Science degree in biology from the University of Nevada, Reno, specializing in wildlife ecology. His graduate research examined the movement patterns of grazing ungulates and included field study of the wild horses of Nevada’s Pine Nut Range. He later completed doctoral-level studies in systematics, ecology, and biology at the University of Kansas and Durham University in the United Kingdom.
He is the founder and president of the nonprofit Andean Tapir Fund and its Wild Horse and Burro Fund. His work has included ecological field surveys, habitat assessments, population observations, conservation proposals, public presentations and consultation with government agencies, conservation organizations and policymakers.
Selected Wild Horse and Burro Research and Publications
Downer’s work on wild equids includes field studies and ecological reports concerning the Salt River horses, the Heber horses and numerous federally managed wild horse and burro populations throughout the West.
Among his principal publications and reports are:
Heber Wild Horses of Arizona’s Apache-Sitgreaves National Forests with 40 Ecological Transect Results and Herd Description, a 124-page, photo-illustrated and peer-reviewed study published in 2022 by Cheiron: The International Journal of Equine and Equestrian History. Available at https://trivent-publishing.eu/home/149-cheiron-vol-2issue-2-2022.html or click on this link: https://thewildhorseconspiracy.org/heber-asnf-mustang-report-11-2022/
Ecological Report on the Salt River Wild Horse Herd and Associated Ecosystem, prepared following field research and submitted to the Tonto National Forest.
Observations and Ecological Evaluations of Wild Horse and Burro Herd Areas, 2016–2018, examining herd conditions and habitats across multiple western management areas. . https://thewildhorseconspiracy.org/wp-content/uploads/2019/07/OBSERVATIONS-EVALUATIONS-WILD-HORSE-BURRO-HERD-AREAS-2016-2018-FINAL.pdf Also published on scientific websites.
Report on Wild Horse Herds and Habitats in Western Utah and Eastern and Central Nevada, with particular attention to the Sulphur and Conger herd management areas. https://thewildhorseconspiracy.org/2021/04/17/report-on-wild-horse-herds-and-habitats-in-western-utah-and-eastern-and-central-nevada/ Also published on scientific websites.
*https://thewildhorseconspiracy.org/2015/12/30/report-on-salt-river-ecosystem-tonto-national-forest-arizona-with-focus-on-wild-hors… Also published on scientific websites.
The Horse and Burro as Positively Contributing Returned Natives in North America, published in the American Journal of Life Sciences. http://www.sciencepublishinggroup.com/j/ajls) doi: 10.11648/j.ajls.20140201.12
Another link for the above article: https://www.researchgate.net/publication/274006946_The_Horse_and_Burro_as_Positively_Contributing_Returned_Natives_in_North_America
Proposal for Wild Horse and Burro Reserve Design as a Solution to the Present Crisis, published in Natural Horse and presented to the Bureau of Land Management and the National Wild Horse and Burro Advisory Board. And recently in early January of 2025 he gave a strong critique of BLM and US Forest Service wild horse and burro conservation program with suggestions for its reform. Here’s the link: (5) National Wild Horse and Burro Advisory Board For the board’s meeting at The Officers’ Club Ballroom
He is also the author of The Wild Horse Conspiracy, first published in 2011 & new edition 2014. Illustrated. Index and Bibliography. 313 pages. www.amazon.com/dp/1461068983 and Wild Horses: Living Symbols of Freedom, published in 1977, Western Printers and Publishers, Sparks, NV. Illustrated.
His articles and commentaries on wild horse ecology, public-land policy, reserve design and conservation have appeared in publications including the Reno Gazette Journal, The Nevada Independent, Reno News & Review, Environmental News Service, The Record-Courier, Horseback Magazine, Natural Horse and Horsetalk.
Conservation and Scientific Experience
In addition to his work with wild equids, Downer has conducted extensive research on the endangered mountain tapir of the northern Andes. His scientific and conservation publications have appeared in the Journal of Zoology, Oryx, Mammalian Species, Wildlife Conservation, BBC Wildlife and publications of the International Union for Conservation of Nature.
His mountain tapir research has addressed habitat use, diet, geographic distribution and the conservation of tropical montane ecosystems in Ecuador, Colombia and Peru. He has contributed to international conservation reports, scientific reference works and species action plans.
Throughout his career, Downer has emphasized the importance of field observation, site-specific ecological analysis, habitat connectivity, viable population levels and reserve design. His work advocates management decisions based on transparent evidence, comprehensive ecosystem evaluation and the long-term preservation of naturally functioning wildlife populations.
Organizations and additional information
Andean Tapir Fund and Wild Horse and Burro Fund
Minden, Nevada
andeantapirfund.com
thewildhorseconspiracy.org