The Wild Horse Conspiracy

Will There Be a Healthy Future for Americas Wild Horses by Craig C Downer

Will There Be a Healthy Future for America’s Wild Horses and Burros IN THE WILD?
PZP or Reserve Design? You Decide!

By Craig C. Downer, Wildlife Ecologist, Wild Horse and Burro Fund, P.O. Box 456, Minden, NV 89423-0456.
September 24st, 2016

On September 7th, 2016, I participated in the National Wild Horse and Burro Advisory Board rangeland tour of the Antelope Valley Wild Horse Herd Management Area (HMA); and on September 8th, I again participated in this board’s official meeting at the historical Stockman’s Hotel in Elko, Nevada. Though both tour and meeting provided for some public input, these were “one slick operation” by BLM officials and certain members of the board. This event aimed to convince all board members as well as the public of a “wild horse overpopulation crisis” with a pre-meditated selection of sites to visit and points to make. And I can well understand why a person with little knowledge and background on wild horse and public lands issues or with a pre-existing selfish agenda could be easily stampeded into accepting the over-population myth.
Indeed, on Friday, September 9th, the board voted 8 to 1 to recommend disposal of ca. 44,000 wild horses and burros currently in holding throughout the United States. If accepted by the BLM, such a recommendation would result in the cruel killing of most of these national heritage animals.
Being all too aware of how wild horses and burros have been set up to fail, all too aware of how they have been used as scapegoats for ecological problems that overpopulated humans have basically caused, I was relieved that BLM officials did not – at least for now – accept their appointed board’s advice. I was also pleased to learn that BLM recently cancelled certain surgical sterilization experiments on over 200 captured wild mares in Oregon and others in Wyoming for which over $11 million dollars had been allocated.
The board’s recommendation would have been tantamount to murdering nearly all of the 44 thousand horses and burros in holding. This proposed bloodbath created an enormous national and international outcry, becoming a global bone of contention. And I find it heartening to see evidence that so many people care about the wild ones and their right to live freely and naturally.
Horses and their burro cousins are highly-evolved beings, fellow sojourners on planet Earth, companions who have lived and labored alongside us humans for many generations –even several millennia! What horses and humans have experienced together concerning Life’s unfolding story is truly awesome! Could this be why the cavalier disposal of the lives of so many horse souls rankles so deeply and with so many?
Today a great moral challenge stridently calls for us humans to more fairly and justly treat our fellow inhabitants of planet Earth. We must give these fellow conscious beings the life they deserve for a change! In the case at hand, horses present highly evolved beings present here on Earth for millions of years of free and natural living, often in wide-open spaces. In diverse ecosystems, they have developed intricate relationships with an astounding diversity of plants and animals and in a way that is truly splendid. As an ecologist, I realize that they are mutually complemental to the other species of fauna and flora. And that they are extraordinarily beautiful should give us some clue as to why they are pleasing to Heaven.
Such realizations occurred to those who established the Wild Free-Roaming Horses and Burros Act of 1971 (WFHBA). This was one of the first times Americans decided to do something major that was genuinely good for a fellow species. And it defied centuries, even millennia, of human self-absorption, thoughtlessness, cruelty and greed. For rather than merely continuing to take from, we humans actually chose to give back to horse kind something of true worth and excellence: their natural freedom to live on their rightful natural land, or home. In other words, to be themselves!
Along with the Wilderness and similar acts, the WFHBA was a “great forward leap for mankind.” Yet, an “all-points bulletin” today concerns our government’s emerging plans for America’s last remaining wild horses and burros. As a wildlife ecologist and even more as a human being who appreciates horses in the wild, I perceive their enemies not only among those traditionally opposed to them, but in our very government and even among people who claim to be wild horse advocates yet who are quick to overly compromise the future of these wild horses and burros as naturally living Earthlings! Why are the latter buckling under to the wild horses’ and burros’ traditional detractors and enemies? It seems that they are being duped into conceding to plans that will only ensure the decline of the wild herds. Many of us believe that this pusillanimous position must not pass! (No pasara! as we speakers of Spanish say.)
Core to what’s wrong are the so-called “Appropriate Management Levels” (AMLs) that have been assigned to the legal wild horse and wild burro herds on their legal lands throughout the West, both on BLM and US Forest Service lands. And along with these, the failure to fairly allocate natural resources for truly viable populations. These AMLs are simply much too low! They are genetically non-viable and would result in under-populated herds.
Any group of creatures that senses itself to be underpopulated usually “struggles to survive,” as Charles Darwin so aptly stated. Herd numbers as well as the locations and sizes of Herd Management Areas (HMAs) have been too arbitrarily set to fit the demands of cattle and sheep ranchers, big mining corporations, expansion-hooked land developers, ORV rippers up of the land, and the kill-focused hunting establishment. As is so typical, the root of the problem lies with that thoughtlessness and greed that infects too many humans today. The consequence has been many millions of acres of zeroed-out, though still legal, herd areas, and herd sizes and the sizes and habitat composition of HMAs (BLM) and Territories (US Forest Service) that are simply not adequate to the long-term survival needs of those wild horses and burros who still remain. To my very bones I feel that we humans must rise to the great moral challenge concerning the horses and burros and their right to live free. And this also has to do with our own success as a species, for it concerns obeying the laws of Higher Justice that govern the universe.
Truly realizing and living the noble intent of the WFHBA will make America great again, allow it to stand uprightly on solid moral ground. We shall learn to share the land and freedom with the wild ones, and this lesson shall be our salvation. We shall no longer restrict and exploit such “paragons of Nature” as the horses and their rightful lands in such a way that denies them their true place in the world we share with them as home. Today we have arrived at a crucial crossroad, a critical turning point:

Faulty PZP-type Choice for America’s Wild Horses and Burros
Shall we only continue to restrict and distort the true natures of the horses and burros and to ever greater degrees, as well as their proper habitats here on Earth? Shall we only continue to deny them genuine freedom here on Earth by condoning marginally productive, water-deprived, and un-whole habitats that have been carelessly and deviously assigned for them? Shall we be cornered into accepting the application of harmful, FDA-classified pesticides such as Porcine Zona Pelucida, or PZP, GonaCon, SpayVac, etc.? These drugs, vaccines, inhibitors of healthy horses – call them what you like – only distort and suppress the true health and well-being of vigorous wild horses and burros! And then do we expect the wild horses and burros so violated to fit into unfairly small and inadequate habitats that do not provide their long-term survival needs? No! Such marginal habitats, substandard population numbers, and biologically compromised individuals are simply unacceptable! They would not be genetically viable and would only set the horses and burros up for inbreeding suppression while at the same time preventing their filling their ecological niches in a harmoniously adapted way. And these animals already face enough survival challenges without having to deal with the violation of their most intimate parts!
Is PZP really a solution that works for the horses/burros?
I have participated in many wild horse and burro meetings and heard talks given by experts describing PZP and its actions on wild horses, including by PZP’s inventor Dr. Jay Kirkpatrick and by Dr. Daniel Rubenstein, a behavioral zoologist who has studied PZPed wild horses in nature. I have also perused many scientific and popular articles about the effects of PZP upon wild horses, both short- and long-term, and both upon individuals and their social groups. Here are some of the major proven damages to wild horses caused by PZP:
(1) PZP weakens immune systems of individuals and their herds since it inhibits reproduction in horses with stronger immune systems. Horses with weaker immune systems are precisely those who reproduce in greater numbers in PZP-treated herds. Eventually, PZP weakens wild horse herds’ overall immune systems. (Reference: Gray, M.E. & Cameron, E.Z. 2010. Does contraceptive treatment in wildlife result in side effects? Reproduction 139: 45-55.)

(2) Increased stress is experienced by mares who have been successfully darted by PZP and by other members of their social bands. This is because of PZPed mares’ frustration in completing their natural reproductive cycle, which affects the other members of their bands. Ironically, it is precisely the mature and stable, more content and non-PZPed bands that do, in fact, cause a slowing of reproductive rates, as years of research by the International Society for the Protection of Mustangs and Burros (ISPMB) and others abundantly proves. (Reference: Sussman, Karen. 6/6/2015. Suspicious deaths with use of anti-fertility drugs. ISPMB Journal.

(3) PZP adversely affects mares’ hormonal systems and consequently the social groups to which they belong. PZPed mares become irritable, aggressive, and more masculine, causing disharmony in their bands. PZP lowers estrogen and increases testosterone in mares and also produces ovarian cysts. Cysts increase testosterone levels. (Reference: U.S. National Library of Medicine. National Institutes of Health. Ovarian overproduction of androgens. (Reference:

(4) Auto-immune oophoritis, aka ovaritis or inflammation of ovaries, and also stillbirths result from PZP. Autoimmune oophoritis can lead to the development of other autoimmune diseases. (Reference: Kaur, K. & Prabha, V. 2014. Immunocontraceptives: New Approaches to Fertility Control. BioMed Research International, Vol. 2014, Article ID: 868196.)

(5) PZP-darted herds in Little Book Cliffs, McCullough Peaks, and Pryor Mountains wild horse legal herd management areas gave birth nearly year-round, i.e. 341 days, rather than in the normal spring season. This exposed PZPed wild mares and their offspring to extremes of temperature, and, consequently, to suffering and death. (Reference: Ransom, J.I. et al. 2013. Contraception Can Lead to Trophic Asynchrony between Birth Pulse and Resources. PLoS ONE 8(1): e54972. Doi: 10.1371/journal.pone.0054972.

(6) It is quite disturbing that PZP antibodies transfer to foals from the mare through the placenta while they are in the womb as well as through mare’s milk. These antibodies react with and bind to the zona pellucida of female newborns. Yet, BLM regularly administers PZP to pregnant and lactating mares in spite of these published scientific findings. (Reference: Sacco, A.G. et al. 1981. Passage of zona antibodies via placenta and milk following active immunization of female mice with porcine zonae pellucidae. Journal of Reproductive Immunology. 1981, December; Vol 3, Issue 6: pages 313-322.)

(7) Weakening of immune system subjects wild horses to mal-adaptiveness to unforeseen major changes such as are occurring due to Global Warming, or catastrophes such as epidemics or wildfires. (Reference: Gray & Cameron, 2010, op cit.)

(8) PZP causes the immune system to attack and destroy the ovaries and produces a large variety of adverse effects. (References: Gray & Cameron, 2010, op cit.; Kaur & Prabha, 2014, op. cit.)

(9) By extending the lifespans of PZPed mares, PZP creates abnormal numbers of aged, sterile mares. This disadvantages younger horses, who continue to be taken away by BLM roundups to reach arbitrary AMLs. This appeases livestock or other wild-horse-adverse interests on the public lands, rather than respecting the General Public, whose majority values wild horses and burros and wants them to be fairly treated. (Reference: Knight, C.M. & Rubenstein, D.I. 2014. The Effects of Porcine Zona Pellucida Immunocontraception on Health and Behavior of Feral Horses (Equus caballus). Princeton University thesis, Dept. Ecology & Evolutionary Biology.)

(10) PZPed mares are no longer reproductively active in the wild horse population, thus diminishing the genetic viability of the herd. The resources they consume would otherwise contribute to reproducing adults and their offspring and maintain the vigor of the herd into ongoing future generations that adapt to ongoing environmental changes, thus assuring their long-term survival. (Reference: Ransom, J.I. et al. 2013, op. cit.)

(11) PZP is a safety hazard to humans, especially to females who administer it. (Reference: Devlin, M. 2015. Fact Sheet: The Truth about PZP.
For these and related reasons, I believe that PZP will seriously harm and undermine the vigor of wild horse and burro populations that our nation’s laws mandate us to protect and preserve, as well as to manage. The restoration and maintenance of herd vigor is essential to the ongoing ecological adaptation and long-term survival of each herd. Healthy reproduction is key to healthy wild horse and burro individuals, bands and herds. Tampering with reproduction produces a variety of aberrations that lead to dysfunctional and disordered wild horses. This results in a decline of the herds.
I have heard from many people who closely observe and/or live near wild horses treated with PZP. They describe many still-born or defective foals produced by mares in whom the effects of PZP have worn off, permitting them to again try to reproduce. Also please consider that after a few to several years of yearly application, PZP generally produces total sterility in mares, depending upon the strength of their individual immune systems. This calls into serious question the proclaimed “reversibility of PZP” to enable mares to reproduce again! To reiterate: of great concern is the fact that PZP is less effective in those mares with weakened immune systems. Hence, the wide-spread use of PZP among America’s last wild horse/burro herds – nearly all below minimum viable population (MVP) level – will seriously undermine their long term survival.
But thankfully there exists an honorable alternative to PZP, and similar horse-disrespectful “quick fixes”. As a wildlife ecologist, I have formulated a sound alternative to PZP and similar invasive proposals. This Reserve Design strategy would restore long-term viable, ecologically well-adapted, and naturally self-stabilizing populations of wild horses and burros throughout the West. (References concerning Reserve Design: Peck, S. 1998. Reserve Design. In: Planning for Biodiversity: Issues and Examples. Island Press, Washington, D.C. Pages 89-114; Soule, M.E. & Terborgh, J. 1999. Continental Conservation: Scientific Foundations of Regional Reserve Networks. Island Press, Washington, D.C.; Downer, C.C. 2010. Proposal for wild horse/burro reserve design as a solution to present crisis. Natural Horse Volume 12, Issue 5, pages 26 to 27; Downer, C.C. 2014. The Wild Horse Conspiracy,, look up “Reserve Design” in Index.)

Reserve Design: the Intelligent and Caring Choice for America’s Wild Horses and Burros
If followed correctly, the unanimously passed WFHBA would have set aside somewhere between 54 million and 90 million acres for the preservation of wild horses and burros in the wild. Lamentably, the rights of these animals—and their human supporters—have been undermined by wild horse and burro enemies, including officials charged with their protection. Current policies toward these “national heritage species” are thinly disguised plans for reducing the herds to cripplingly low, non-viable population numbers. These levels would be unable to sufficiently and adequately reproduce so as to survive into the long-term future. Too often the plan has been to simply eliminate them from their legal areas, i.e. “zero-out”. Indeed, anywhere from 22 million to 40 or more million legal acres have been declared officially empty and “not for” the wild horses and burros or simply ignored at the onset of the WFHBA in the early years of this act (see Downer, C.C. 2014. The Wild Horse Conspiracy).
Some wild horse advocates and observers say there are only 33,000 wild horses and burros remaining on America’s public lands as independently estimated for mid-2016 (Louise, Katia, wild horse documentary filmmaker, pers. comm.). Even if the official BLM figure of 67,027 wild horse and burros remain on the public lands (55,311 horses & 11,716 burros [BLM report of March 1, 2016]), either level would be out of step with the amount of ecologically appropriate habitat where these animals have a legal right to live. The small number of horses and burros our government intends to leave on each of the ca. 179 remaining BLM-designated areas is a sure prescription for the over-fragmentation and isolation of wild horse/burro populations. This would only jeopardize their long-term survival, compromising their true vigor in the wild.
The nationwide population of wild horses and burros that our government plans to allow as the high end Appropriate Management Level is only 26,715. This would be composed of only 1,676 individual wild horses and/or burros in Arizona; 2,200 in California, 812 in Colorado, 617 in Idaho, 120 in Montana, 12,811 in Nevada, 83 in New Mexico, 2,715 in Oregon, 1,956 in Utah, and 3,725 in Wyoming. (Source: Herd Area and Herd Management Area Statistics as of March 1, 2016. BLM, Washington, D.C.) These assigned population levels are very unfair and cater to wild horse and burro detractors while largely disregarding the General Public that strongly support this Quality of Life issue.
Our government’s current goal of and plans for drastically reducing small and genetically vulnerable wild herds include the partial—and very possibly total—sterilization of mares through PZP injection. These plans also include the unnatural skewing of sex ratios to establish excess males, even in the naturally harem social structure of naturally living horses in which females are usually more numerous. And even more invasive measures have been planned in the past and are likely to crop up again, including painful—often lethal castration of stallions and the ovariectomies (removal of ovaries) of mares (thankfully recently cancelled in Oregon and Wyoming), as well as the individually deranging and socially disruptive injection of sterilization drugs or vaccines, such as PZP.
Clearly, our wild horses and burros are in a very critical situation today. I judge them to be more imperiled than they were in 1971 just before the passage of the WFHBA when they were “fast disappearing from the American scene”—and I used to work with Wild Horse Annie. We must quickly respond with a well-conceived plan for reforms that will restore the true rights of wild horses and burros upon our public lands. These lands belong to all Americans, not just to resource exploiters, whether officials of corporations or private individuals. As a wildlife ecologist and deeply rooted native Nevadan personally familiar with many of the West’s wild horse and burro herds, I strongly urge the restoration of these deeply rooted North American native species. Their return to North America should be as genetically viable and naturally self-stabilizing herds that are allowed to adapt ecologically to each specific region where they have legal right. This can be accomplished by following the sound principles of Reserve Design. Such a plan would end cruel, disruptive roundups and reproductive manipulations – practices that mock the true intent of the 1971 WFHBA by causing untold suffering and death to these beautiful and highly evolved, sensitive, wise, and freedom-loving creatures.
Reserve Design combines ecological, biological, social, and political considerations in order to achieve desired results. Basically, it involves setting aside areas of complete year-round habitat where human intervention is buffered against and where natural processes are allowed to reestablish natural checks and balances. Reserve Design will achieve internal harmony for the diverse, yet interrelated, species living within each wild horse/burro-containing ecosystem.
Critical steps for realizing Reserve Design in wild horse and wild burro habitats are as follows:
[1] Properly identify the long-term survival requirements for viable equid population levels to be accommodated in each reserve. Our chief focus would be to promote wild horse/burro-containing ecosystems of adequate size and condition to sustain viable equid populations and where plant and animal species are allowed to adapt naturally over the generations and in inter-balanced fashion. The level of 2,500 individual has been recommended for the viability of an equid population by the IUCN SSC Equid Survival Group (Equid Action Plan, IUCN SSC ESG, 1992).
[2] Conscientiously identify appropriate ecological areas suitable for the implementation of wild horse/burro-containing reserves. This would involve travel to, on-ground inspection of, flights over, and GIS analysis of a wide variety of places throughout the West. This would also entail setting up Cooperative Agreements under Sections 4 and 6 of the WFHBA in order to achieve complete habitats around the federally designated wild equid lands and involving both private and other government lands such as state and local.
[3] Wherever possible, wisely incorporate natural equid predators (such as puma, bear, and wolf) that would both limit and tone/strengthen, wild horse and burro populations.
[4] Wherever possible, wisely incorporate natural barriers that would limit the ingress and/or the egress of certain species, including the wild horses and burros. This would avoid conflicts and set up conditions for the natural self-regulation of populations.
[5] Identify where buffer zones, artificial barriers, or other means of impeding movements in and out of a reserve should be established in order to keep the species in question from coming into conflict with humans. Buffer zones possibly involving non-injurious means of “adverse conditioning” could be employed as well as “positive reinforcement” as a means of encouraging the wild equids to stay within the reserve, as for example, by providing all of their habitat needs. Also, “semi-permeable barriers” that do not restrict most species but do prevent equids from passing out of the reserve may be used. These means would be described in practical detail and as tailored to fit each specific reserve area.
[6] Identify the presence and abundance of necessary food, water, shelter, mineral procurement sites, elevation gradients for seasonal migrations, etc., that will accommodate the long-term habitat needs of long-term viable wild equid populations. Such will also allow the natural rest-rotation of foraging between the natural subdivisions of the reserve. Fences within the reserve that impede the free-roaming lifestyle of the wild equids will be located and their removal accomplished. The intrinsic Carrying Capacity of the land in question will also be estimated as closely as possible. Such will be based upon the Productivity of forage adequate to at least a minimally viable population of wild horses/burros. Besides food, this determination will take into account other survival factors such as water, minerals, shelter, breeding and nurturing habitat, seasonal migrations, and needed protection from existing threats to the wild equids.
[7] Identify geographical regions whose human inhabitants are benignly disposed toward the creation and long-term implementation of extensive, ecologically balanced wild horse/burro-containing reserves. This would involve traveling to different areas and setting up meetings with pertinent individuals, town and government officials, etc. This also relates to the setting up of Cooperative Agreements under Sections 4 and 6 of the WFHBA, as mentioned above.
[8] Identify ways of and benefits from implementing Reserve Design that result in win-win relationships centered on the presence of wild horses and burros. Ecotourism is one major possibility here, and wild horse/burro viewing tours have already proven to be successful in several states, including Craig London’s tours to the Montgomery Pass wild horses of eastern California. Restoring native ecosystems, including soils and native species, would be a major ecological benefit. The reduction of flammable vegetation through equid grazing and the restoration of hydrographic basins through the enrichment of soils, would be other major, positive contributions by wild horses and burros. Another major benefit concerns the prevention of catastrophic wildfires that over-burn vegetation, sterilize soils and denature their stored seed banks. Such fires can set the life community back to very primitive evolutionary stages. Indeed, it can be strongly argued that the restoration of wild equids in North America is crucial to combating life-disrupting Global Warming itself.
[9] Of key importance is informing the public concerning the many ways that horses and burros, as ecological “climax” species, self-limit their own populations once their respective ecological niches are filled in any given bounded area. This knowledge is key to realizing a humane relationship with these animals, a relationship that does justice to and demonstrates respect for them. And it is this respect and appreciation on the part of us humans that is key to allowing the horses and burros to fulfill their important natural roles within the life community.

Whom to Contact to Help Wild Horses and Burros:
Please contact your Senators and Representatives, the President, the Secretary of Interior and its Bureau of Land Management; and the Secretary of Agriculture and its US Forest Service. Both of these agencies are mandated by the WFHBA to preserve and protect as well as to manage the wild horses and burros and their legal lands and resources for the benefit of the former.
Also contact your state governor and state, county, and municipal officials concerned with wildlife and natural resources. Get in touch with the media: newspapers, magazines, TV and radio stations. Make all of the above aware of what is needed to stop the over-reduction or zeroing-out of the herds and the cruel abuse of wild horses and burros, whether through drugging, vaccines, surgeries, or other unnatural and invasive methods. Rather, persist in the restoration of the wild horse and burro herds and their habitats to viable levels, healthy conditions and sizes. This will be to restore the pure intent of the law.
A key committee to contact right away is the U.S. House of Representatives’ Appropriations Committee, particularly its Interior, Environment & Related Agencies Subcommittee. The telephone number of the latter is (202) 225-3081. Emails of staff to contact are and This subcommittee is now deciding which direction to take in regards to the wild horses and burros. It has been hearing too exclusively from traditional wild horse and burro enemies. Those of us who value and appreciate the wild horses and burros and their rightful place in the world of nature must set the record straight for these wonderful and ancient presences on Earth. We must not allow their enemies or those ignorant of their worthiness prevail!
The spirited and intelligent horses and burros are depending on you and me! In addition to contacting the above, be sure to contact the President of the United States and the White House staff at (202) 456-1111 (TTY/TTD: (202) 456-6213). Switchboard (202) 456-1414. You can also do this by email at or
You may contact your Senators and Congressmen/State Representatives (federal and state) by linking on internet with “Elected Officials / USA Gov”. This will provide you with the contacts you require for federal, state, and local offices. The link is:
Also contact the natural resource and public lands committee and subcommittee in the U.S. Senate.
On behalf of our wonderful wild horses and burros, I sincerely thank all of you for your caring and for your effective action. Together we can assure their rosy future, one they surely merit.

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