Wild horses and wild horse management - Non-profit organizations wrong: chemical use on wildlife populations is flawed
A Wildlife Article from All-Creatures.org

FROM The Fund for Horses
September 2021

Donation-funded wild horse non-profit activist organizations are seemingly helping themselves by keeping a decades-old range war alive!

Wild Horses

 For the reasons cited herein below, I strongly urge that wild horse non-profit activist organizations immediately stop promoting and supporting wild horse management using porcine zona pellucida (‘PZP’).

The use of this chemical is helping to send native species American wild horses into extinction, as I explain herein below and in my recent article, incorporated herein by reference.

“Fertility control in free‐roaming wildlife populations has been associated with changes in immigration (Ramsey 2005; Merrill, Cooch & Curtis 2006), decreased group fidelity (Nuñez et al. 2009; Madosky et al. 2010), increased survival (Caughley, Pech & Grice 1992; Kirkpatrick & Turner 2007; Williams et al. 2007), altered reproductive behaviour (Nuñez, Adelman & Rubenstein 2010; Ransom, Cade & Hobbs 2010) and shifted phenology (Ransom, Hobbs & Bruemmer 2013)” ~ Ecological feedbacks can reduce population‐level efficacy of wildlife fertility control. [1]

The use of chemicals to control wild horse populations (wildlife) disintermediates evolutionary Natural Selection and leads to genetic erosion and social disruptions in wild horses (equids). And using chemicals offers no genuine long-term sustainable benefits for either side of the wild horse management debate. [1]

Via an effort by ‘Friends of Animals’ for the herd of wild horses in the Pryor Mountains, it’s likely that wild horses might soon have an initial listing under the Endangered Species Act (‘ESA’).

While such an ESA listing appeals to many as an initial segue to a larger ESA listing for wild horses, it will certainly cause escalated difficulties in the wild horse management debate and struggle across the public lands where wild horses are commingled among livestock and in competition with livestock production.

Wild horse activist non-profits organizations who are engaged in the promotion of the usage of PZP (and or GonaCon) on wild horse populations as a management solution are supporting a highly-flawed initiative that is hurrying the demise of wild horses along, and is consistent with the plan known as the ‘Path Forward’. See https://www.energy.senate.gov/services/files/0869B02B-E9C5-4F0B-9AE8-9A8A1C85293E.

The Path Forward can be argued as the planned genocide of remnant herds of native-species American wild horses, and will arguably lead to an ultimate ESA listing of native American wild horses when wild horse populations crash.

The clear outcome of the current trajectory is not ideal for the sustainable preservation of American native species wild horses, nor beneficial for the agri-production-ranching industry.

The result is an overall management failure, which has been and is currently orchestrated to some extent via the influence of the largest wild horse non-profit activist organizations on politicians, via their lobbying, leading to what we are seeing across the landscape today; the largest roundups in recent history. And this catastrophic management failure will surely continue the turmoil regarding public lands management for both wild horse and livestock-production advocates.

Both sides of the public lands debate desperately need a mutually acceptable solution, which somehow seems to elude the biggest (as in: loudest in the media) wild horse non-profit organizations.

One plausible explanation of the current dire management debacle, is that it’s by design, in order to maintain the relevance and perception of ‘need’ for wild horse advocacy non-profits, so arguably, the fight must continue in order to continue the flow of donations.

Obviously, a holistic, cost-effective and sustainable natural solution for wild horses arguably puts wild horse activist non-profits out of business.

As long as the big wild horse non-profits can remain relevant, donations continue to pour-in, which in turn pays the handsome salaries that some non-profit CEOs are paid; some of whom are being paid at scales similar-to for-profit corporate CEOs.

As an example:

According to Charity Navigator, Suzanne Roy, the Executive Director of the American Wild Horse Preservation Campaign, ‘AWHC’, which promotes the use of PZP, was paid $78,115.00 in 2019. They have a fancy website here: See https://americanwildhorsecampaign.org.

The AWHC IRS Form 990 from 2019 shows that $468,655.00 was spent on ‘salaries, other compensation and employee benefits’. The address listed on the AWHC IRS filing is that of a plush residential home with an address of 5613 Hoag Place, Davis CA. Zillow values this residence at $1.1-Million. (see image).

Based-on AWHC’s IRS Form 990 information, some people might ask the question: is Ms. Roy living the high-life when compared to some other wild horse advocate non-profit executives, who are engaged in a more altruistic manner, by spending less money on themselves, and more on the wild horses?

After 40-years and arguably over $100-Million in donations to wild horse non-profit organizations spent, what are the results? The word ‘disaster’ comes to mind.

Even after 40-years and ~$100-million in spent donations, the result is, the most aggressive and devastating roundups in recent history.

These massive roundups, coupled with using PZP (and GonaCon) on the relatively few remaining wild horses left on the range puts a cinch on their demise as I outline in this article: See https://rtfitchauthor.com/2021/09/06/moving-past-failed-wild-horse-advocacy/.

A better management paradigm for wild horses and burros

Management of Wild Horses using the plan ‘Wild Horse Fire Brigade’ (‘WHFB’), which is a proven model and based upon empirical experience and research, saves taxpayers about $100-million annually in regard to costs for roundups and long-term off-range housing, and that’s just the immediate benefit of WHFB.

WHFB doesn’t require donations or government funding to be sustained (maybe the reason why it’s not supported by non-profits?). In fact, it’s a cash-positive natural management paradigm that would benefit taxpayers! And over a short period of time would save taxpayers hundreds of millions of dollars annually.

America has about 100-million acres of what is called ‘critical wilderness’ areas under the management of government agencies, primarily the Bureau of Land Management (‘BLM’), U. S. Forest Service (‘USFS’) as well as states to a much lesser degree. About 20-million of those critical wilderness areas are located in the far western states of California, Oregon and Washington.

These critical wilderness areas containing forests, wildlife, watersheds and fisheries, which are not part of the currently designated Herd Management Areas (‘HMAs’), are at grave risk from catastrophic wildfire due to depleted native species large-bodied herbivores (deer, elk wild horses). Unlike the desert landscapes where wild horses face water and forage shortages, these areas are rich in water and forage.

For time immemorial (prior to humankind’s activities depleting large native herbivores) evolved native-species large-bodied herbivores, especially wild horses, had naturally managed grass and brush fuel loading across the landscape, thereby sustainably and cost-effectively, managing the key ‘1-hour class wildfire fuels.

Unlike invasive species ungulates, cattle, sheep and goats, which did not co-evolve with North American flora, co-evolved wild horses manage native vegetation in a manner that is symbiotic to all the flora and fauna within the same ecosystems. Ungulates strip-off native plants, gasses and forbs via the digestion of their seeds due to their complex digestive systems.

Ungulates (cattle, sheep and goats) imported from Africa to American starting in the 15th century, do not share any evolved ecological mutualisms with North American flora. This is a process that requires tens of thousands of years of co-evolution on a given landscape. And given that all wild horses in the world evolved in North America, starting 55-million years ago, they have indeed co-evolved with American native flora.

As such, wild horses uniquely have co-evolved mutualisms with North American flora and fauna. This is of critical importance in regard to wild horse management, as well as to sustainable land and forest management, and especially as it relates to wildfire fuels.

Wild horses are native species ‘keystone herbivores’

Wild horses have simple digestive systems that allow native seeds to survive when consumed and to be subsequently distributed across the wilderness landscape, thereby propagating the native flora of wilderness areas. [2]

The published study “Impact of Wild Horses on a Wilderness Landscape and Wildfire” contains empirical evidence of the foregoing and is also well-supported by leading published science that is peer-reviewed.

America’s ‘critical wilderness areas’ are manifestly unsuited for any livestock production due to:

a) Laws that limit uses and also impact transportation and management logistics in such extremely remote areas (no motorized vehicles); and

b) Are comprised of very remote and extremely difficult terrain with no viable road systems (many roads are single-track 4X4 roads) for at-scale livestock hauling or logistics; and,

c) Critical wilderness areas maintain full complements of Apex predator populations.

The combination of the foregoing and other issues, make the costs of livestock production in such areas cost-prohibitive.

Re-populating critical wilderness areas with native species American wild horses provides great value.

Settled, published science shows that reestablishing the native species herbivory on the landscape reduces both the frequency and intensity of wildfire! [3]

The current annual combined costs related to wildfire suppression plus socioeconomic losses is now in the realm of $100-Billion! And with the year-over-year increases in numbers and intensity of catastrophic wildfires, this already enormous cost will continue to grow.

Each wild horse deployed into a ‘critical wilderness area’ provides taxpayers with $72,000.00 (each horse) in wildfire fuels reduction services over the course of its average life span.

The cash difference between the off-range costs of warehousing a wild horse over its life ($46,000) and the value each wild horse rewilded or located into a ‘critical wilderness area’ in a wildfire fuels reduction role, provides a positive benefit of $118,000.00 in value per wild horse deployed.

The 1971 Act can be properly amended, to allow the rewilding and relocating of wild horses, without losing its intent or protections, by adding a short paragraph to Section 1339 that allows new options of ‘rewilding and relocating’, instead of roundups, off-range warehousing and slaughter:

Here is the current language that must be addressed: § 1339. Limitation of authority:

“Nothing in this Act shall be construed to authorize the Secretary to relocate wild free-roaming horses or burros to areas of the public lands where they do not presently exist.”

Proposed amended language (by William E. Simpson II), for § 1339. Limitation of Authority:

“Nothing in this Act shall be construed to authorize the Secretary to relocate wild free-roaming horses or burros to areas of the public lands where they do not presently exist, with the exception that; in Wilderness Areas managed by the United States Forest Service (USFS) and/or the Bureau of Land Management (BLM) containing forests and/or other natural resources at risk of catastrophic wildfire; the BLM and the USFS shall under this Act have authority to re-wild American wild horses and burros from off-range holding facilities and/or relocate wild horses and burros from existing Herd Management Areas into such Wilderness Areas where it is ecologically and economically appropriate.”

Wild Horse Fire Brigade – A Novel Wild Horse Management Paradigm [4]

The proper, naturally sustainable management solution for wild horses involved a combination of two actions:

1) Relocating:

Wild horses from herd areas where they are presently commingled with livestock, where apex predators have been largely eliminated to enhance livestock production; and relocating wild horses into ‘critical wilderness’ areas, which are manifestly unsuited for livestock production for many reasons and where the evolved natural predators of wild horses remain intact. This allows for ‘natural selection’ by the co-evolved predators of wild horses.

Natural Selection is what maintains genetic vigor of the species and also keeps populations in balance.

The reductions (elimination) of apex predators from most Herd Areas over the past 400-years has created a fatal problem for native species wild horses when they are commingled in such areas.

It’s unnatural and highly undesirable to separate any prey animal species from its co-evolved predators, and such management action conflicts with evolutionary biology, which is the case in many present-day BLM and USFS operated Herd Management Areas in regard to wild horses. Using PZP and/or GonaCon chemical contraception is a dangerous temporary band-aid that employs ‘selective breeding’ (artificially controlling which animals breed via contraception), which also leads to genetic decline.

PZP works best on mares with good immune systems. Mares with poor immune systems can and do still foal, and their offspring carry the mare’s genes for poor immunity. This results in a selective breeding program for bad genetics, resulting in progressively weaker herd immunity and increased vulnerability to pathogens.

2) Rewilding:

Instead of housing wild horses off-range at the cost of about $46,000 over the life of each horse, these horses can also be released into the same remote ‘critical wilderness’ areas, where they can join the bands of relocated wild horses (mentioned above). The same natural evolutionary dynamics apply in this action.

Aside from the social breakdown of family bands, genetic erosion and selective breeding that are all part of using PZP on free-roaming native species American wild horses, we find:

“Even on a large animal struck correctly, the dart (contraceptive PZP and GonaCon darts) can cause hemorrhage and hematoma. Misplaced shots can break bones or even kill the animal” (Thomas and Marburger 1964). Report–Muzzle report can cause problems in darting either captive or free-ranging animals. In captive situations, the noise can be more disturbing to animals than getting struck with a dart. Disturbed animals are then more difficult to approach, or the entire group of animals may run away” ~ Page 32; Overview of Delivery Systems for the Administration of Contraceptive to Wildlife”, by Terry J. Kreeger

Violating the intent of the 1971 Wild Free-Roaming Wild Horse and Burro Protection Act

Stalking and shooting wild horses with powerful gas-powered firearms is in itself a ‘harassment’ of wild horses and is an arguable violation of both the intent and codified specifications of the 1971 Wild Free Roaming Wild Horse and Burro Protection Act.

Based-on Terry J. Keeger’s study, by promoting the use of PZP, non-profit organizations are arguably using donation funds to encourage harming wild horses.


1. ‘Ecological feedbacks can reduce population‐level efficacy of wildlife fertility control’

‘Consequences of porcine zona pellucida immunocontraception to feral horses’

‘Genetic variation, inbreeding and chemical exposure—combined effects in wildlife and critical considerations for ecotoxicology’

‘Immunocontraception in wild horses (Equus caballus) extends reproductive cycling beyond the normal breeding season’

‘Effects of porcine zona pellucida immunocontraceptives in zoo felids’

‘Is Wildlife Fertility Control Always Humane?’

2. ‘Influence of ruminant digestive processes on germination of ingested seeds’

‘Ruminant Digestion’:

3. ‘Collapse of the world’s largest herbivores’:
“By altering the quantity and distribution of fuel supplies, large herbivores can shape the frequency, intensity, and spatial distribution of fires across a landscape”. William J. Ripple1, Thomas M. Newsome1,2,Christopher Wolf1, Rodolfo Dirzo3, Kristoffer T. Everatt4, Mauro Galetti5, Matt W. Hayward4,6, Graham I. H. Kerley4, Taal Levi7, Peter A. Lindsey8,9, David W. Macdonald10, Yadvinder Malhi11, Luke E. Painter7, Christopher J. Sandom10, John Terborgh12 and Blaire Van Valkenburgh13 http://advances.sciencemag.org/content/1/4/e1400103.full

4. ‘Can Wild Horses Help Prevent Wildfires in the West?’

William E Simpson
Wild Horse Ranch Productions
+1 858-212-5762
email us here

According to many the plan that could combat the danger of wildfire lies in the complicated history and present role of the wild horse.

Featured Image: Author, Naturalist William E. Simpson II is greeted by a wild mountain stallion in the Soda Mountain Wilderness area.

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