URGENT: Get your comments in by midnight against using PZP on the Onaqui mares in Utah


Send in your own comments before midnight against giving the restricted use pesticide, PZP, made from slaughterhouse pig ovaries today! Email them to blm_ut_cedarmt_onaqui@blm.gov

Marybeth Devlin’s extensive comments will give you some ideas but it’s important to send in your comments using your own words. Keeping it short and sweet is fine. The point to get across is that you don’t what them to be drugged up with an EPA pesticide that sterilizes after multiple use, no roundup and no removal. Request BLM incorporates holistic management for successful management of wild horses on public land.

Comment by Marybeth Devlin

Via email: blm_ut_cedarmt_onaqui@blm.gov
March 6, 2015
Bureau of Land Management
Salt Lake Field Office (SLFO)
2370 South 2300 West
Salt Lake City, UT 84119

Attn: Pam Schuller, Environmental Coordinator
Project Name: Onaqui Mountain Wild Horse Fertility Control Plan EA

Document: Environmental Assessment

NEPA ID: DOI-BLM-UT-W010-2014-0021-EA
Dear Ms. Schuller:

I have reviewed the subject EA and associated documents regarding the plan to continue, and more aggressively apply, the contraceptive Porcine Zona Pellucida (PZP), also known as ZonaStat-H, on the fillies and mares of the Onaqui Mountain Wild Horse herd. I am submitting substantive comments and new information that SLFO would do well to consider. Other information is discussed that you already know, or should know, but on which you have failed to act. For ease of reference, below are the links to the …

News Release


Environmental Assessment — 2015


Cedar Mountain and Onaqui Mountain Wild Horse Herd Management Areas Capture, Treat and Release Plan Fertility Control with Limited Removal — 2012

Public Scoping — Notice Buried — No News-Release — Only 2 Comments

The EA claims that, prior its publication, the required public-scoping was conducted. However, instead of issuing the standard news-release, BLM restricted notification of the scoping-period to a posting on the “Utah BLM Environmental Notification Bulletin Board” (ENBB). However, how would the public know to look on this ENBB, when it is not even one of the options on Utah-BLM’s online “Information Center”?

Not surprisingly, the EA reports that only two comments were received, both in support of BLM’s intensified fertility-control plan and for “managing wild horses on the range within AML.” And who were the two parties that submitted comments in support of birth-control for the Onaqui wild horses and for keeping them within AML?

The first was Iron County, whose commissioners had threatened last July — following the Cliven Bundy standoff — to round up wild horses themselves. Advised that doing so was illegal, Commissioner Dave Miller then co-sponsored a resolution for the states to take over management of the wild horses and burros.


The second comment was from the State of Utah Public Lands Policy Coordination Office, an activist-agency whose goal is to “retake ownership” of Federal land. Here’s the link to an article about the PLPCO, aptly titled “The Wild Bunch”.


How curious that these entities were the only ones who were successful in learning about the scoping period. Did BLM staff alert them to check the ENBB — and where to find it?

What the inadequate number of scoping-comments evidences, is that BLM-SLFO did not provide proper notice but instead, buried that notice where it where it would be hard to find. There are many wild-horse advocacy-organizations that certainly would have submitted comments concerning SLFO’s proposed management-plan for the beloved Onaqui mustangs — if they had known the scoping period was open.

Corrective Action: SLFO needs to restart this process. Re-open the scoping period and properly notify the public. SLFO needs to compile an ample number of diverse comments. The Wild Horse and Burro Program is national in its constituency. Input regarding its management cannot be limited to a few local anti-wild-horse entities.

Public-Comment Period for the EA — Reduced 50 Percent

As if the secretive posting of the scoping notice were not bad enough, SLFO is providing only 14 days for comments on this EA. The standard period is 30 days. By shortening the comment-period by half, SLFO appears to be limiting public-input for a second time — now at the EA-stage of the process.

Corrective Action: This EA must be rescinded until SLFO has completed the re-opened scoping process. Then, when SLFO issues a revised EA per the scoping, a full 30-day comment-period must be offered for public-input. However, to save everyone’s time, the best action is to select the “No Action” alternative, which appears to be the correct path, as is evident by an analysis of the facts.
BLM’s Proposed Action

The EA seeks to implement a fertility-control plan through the year 2020 to limit the Onaqui herd to 160 wild horses. The current AML ranges from 121 to 210 horses; thus, 160 is below the midpoint between the low and high bounds. The EA says that the short-term goal is to reduce population-growth to “less than seven percent” while the long-term goal is to reduce the need for roundups and removals. To achieve this reduction, SLFO would use the one-year formulation of PZP, and field-dart “select mares.” The darting would be conducted on foot, the EA says, but then clarifies that 4×4 vehicles and off-highway vehicles (OHVs) would be used to “access” the Onaqui HMA. Bait-trapping would be used as deemed necessary.

This is not the first time that Onaqui fillies and mares have been subjected to PZP. Previously, however, the formulation used was PZP-22.

How the Plan Would Work

Starting in late March or early April 2015, SLFO staff would begin vaccinating yearling fillies (which BLM refers to as “mares”) with a “primer” PZP-dose. About 30 to 60 days after that initial injection, staff would administer a second “booster” shot to the fillies. The need to give the second injections within a certain time-frame suggests the fillies might need to be gathered and held captive during that interval.

From then on and for the next five consecutive years, “one-year PZP” inoculations would be given. Once a filly-becoming-a-mare reached the age of 6, PZP would be suspended until she produced “a live foal,” after which she would be contracepted “for the remainder of her natural life.” Mares that had previously been vaccinated with PZP — which was the PZP-22 formulation — would receive annual boosters in the time-frame of November through February, but would be subject to dosing at any time of year.

The EA is ambiguous regarding how treated mares would be “identified” for staff-use in the field. Reference is made to a “photo database” and to identification “by color, face, leg, and coat pattern markings.” But mention is also made of mares to be “individually marked,” and that a “number of the horses have a hip brand as well as neck brands from previous PZP treatments.” Thus, it is possible that SLFO will disfigure the Onaqui fillies and mares with huge freeze-marks on the hip for staff’s administrative convenience. If so, persons visiting the HMA will have their experience spoiled by the hideous four-inch-high brands on the fillies and mares’ coat.

The “No Action” Alternative

As required by NEPA, BLM presents a “No Action” option. Per this alternative, SLFO would defer the plan to gather and contracept the Onaqui herd to a later time. Until then, SLFO would continue to monitor the HMA’s vegetation and the herd’s population.

The “No Action” alternative is actually the best option. Suspend contraception and let natural processes function as they will. Allow a natural ecological balance to revive and thrive in the Onaqui Mountain HMA.
PZP — A Pesticide that Is Also a Bio-Hazard

It is inappropriate to treat our wild horses as pests. But that is exactly what BLM does when it injects wild mares with PZP. Rather than being a medicine, PZP — also known as ZonaStat-H — is classified as a pesticide, a contraceptive used on horses labeled “pests.”

Further, PZP is a biohazard, as reflected in the warnings, excerpted below, which are included in the Environmental Protection Agency’s fact-sheet.

Personal Protective Equipment requirements include long sleeved shirt and long pants, gloves and shoes plus socks to mitigate occupational exposure.

A warning that pregnant women must not be involved in handling or injecting ZonaStat-H and that all women should be aware that accidental self-injection may cause infertility.


Meta-Analysis Reveals the Risk of Sterilization from ZP Contraceptives

A recent study-of-the-studies — that is, a meta-analysis — was performed of the research-findings with regard to different contraceptive methods. Among the drugs analyzed were various zona pellucida (ZP) formulations. As it turns out porcine zona pellucida (PZP), from slaughtered pig-ovaries, is not the only ZP contraceptive in use. For instance, a particular ZP vaccine was derived from the ovaries of possums.

The meta-analysis disclosed that ZP contraceptives often result in sterilization, which appears to be caused by ovarian dystrophy, destruction of oocytes in all growing follicles, and depletion of resting follicles. Here are some salient excerpts [with emphasis added] that give rise to concern regarding ZP-contraceptives:

The irreversibility associated with immunization using ZP posed a major hurdle in the development of ZP based contraceptive. While irreversibility is not a major concern in case of wildlife management where long term infertility is often desirable. Therefore further development in this area resulted in production of various marketed products playing an imperative role in wildlife management.

Further studies revealed that the infertility induced in immunized female rabbits was irreversible which could not be restored even after the administration of exogenous gonadotropins. Histological examination of ovaries showed the destruction of oocytes in all the growing follicles along with the depletion of resting follicles. This observation indicated that the infertility was a consequence of ovarian dystrophy rather than inhibition of sperm-oocyte interaction.

The immunization of female bonnetmonkeys was carried out using purified porcine ZP3. High antiporcine ZP3 antibody titers were formed and all the animals were rendered infertile. Only 50% of the animals could regain fertility after the decline in antibody titers.

Significant curtailment of fertility was also observed by using recombinant possum ZP3 in grey kangaroos. Though the results were quite exciting, histological examination of ovaries of immunized animals revealed the presence of atretic follicles with degenerating oocytes.
Saunders Comprehensive Veterinary Dictionary, 3 ed. explains what an “atretic follicle” is:

Definition: atretic follicle — an ovarian follicle in an undeveloped state due to immaturity, poor nutrition or systemic disease; manifested by prolonged anestrus.


It is reasonable to conclude that PZP, whether Native PZP or PZP-22, likely has a similar effect on the ovaries, oocytes, and follicles of wild mares. Thus, permanent loss of fertility — even after one inoculation — can result.

Important: The meta-analysis’ finding that “… infertility was a consequence of ovarian dystrophy rather than inhibition of sperm-oocyte interaction” appears to disprove the theory posited by ZooMontana, which supposed that PZP “antibodies then bind to eggs in the mare’s ovaries and effectively block sperm binding and fertilization …” (cited in the EA). The new findings show that PZP works not by blocking the sperm but by degenerating the ovaries. Given these findings, PZP should be abandoned for use in wild horses.

The meta-analysis report can be accessed at the link below.


Earlier Meta-Analysis Disclosed PZP Side-Effects

The meta-analysis linked below was published in the journal Reproduction. Studies of the side-effects of different wildlife contraceptives, including PZP, were reviewed. [Once on the site, page down to the sidebar on the right of your screen next to “Abstract” and click on “Results” and then on “Discussion.”]


Listed below are the findings with regard to PZP:

1. Males lose body condition while the oft-claimed improvement in female body condition did not hold up.

2. Females experienced increased irritability, aggression, and masculine behavior.

3. Mares remained sexually active beyond the normal breeding season and had more “estrus events.”

4. The possibility of “selecting for immuno-compromised individuals” is raised.

5. Finally, the analysis questions the supposed benefit of mares living much longer than their normal life expectancy.

With regard to Finding Number 4 above, by continuing and even intensifying the use of PZP, SLFO could be selecting for immuno-compromised horses. If a disaster were to strike the Onaqui Mountain herd, fertility would need to be quickly restorable. PZP would work against saving the herd if it experienced a stochastic event.

With regard to Finding Number 5 above, interestingly, the EA cited PZP’s correlation with extended longevity of mares as if it were a benefit. Yet, for purposes of genetic sustainability, increasing the number of long-lived — yet sterile — mares would be disadvantageous to a herd, especially one like Onaqui, which is so low in population already.

Potential Adverse Effects of PZP on a Developing Embryo or Fetus

Recall the EPA’s warning that pregnant women must not be involved in handling or injecting ZonaStat-H. If a mare is administered PZP when she is pregnant, might not her unborn foal be adversely affected by the drug even if the pregnancy itself continued? If the embryo or fetus were female, might the vaccine negatively impact the baby’s reproductive system pre-birth? Might her developing ovaries experience dystrophy? Might she become masculinized as a result? Might she never produce foals, thereby eliminating any genetic contribution on her part? If the embryo or fetus were male, might his reproductive system be affected, considering that the testes correspond to the ovaries?

Until these questions can be answered definitively, PZP should not be used on wild horses, whose numbers are already so low that they could qualify as an endangered species.

Potential Adverse Effect of PZP on Yearling Fillies

At one year of age, fillies are just reaching puberty. Is it ethical to subject them at that tender age to a vaccine that will wreak havoc with their ovaries, perhaps sterilizing them permanently? Is it right to masculinize a herd’s fillies?

PZP — Unintended Consequences and Social Disruption

BLM’s proposed action would treat both fillies and mares with the Porcine Zona Pellucida (PZP), a 95-percent-effective contraceptive pesticide. This misguided plan endangers the Onaqui Mountain herd’s long-term survival. The PZP contraceptive is not without risk and can have unintended consequences, such as:

If fillies and mares are in excellent health and condition at the time they are treated, PZP can cause too strong an immune-response, resulting in long delays in restoring fertility or outright sterilization after even the initial treatment. Multiple injections are likely to result in irreversible loss of fertility. That could be one reason why PZP is not used in humans. Note that SLFO intends to administer multiple, consecutive injections.

Ironically, PZP works less well in mares that are in ill health or poor condition — they are likely to conceive despite PZP treatment. Thus, the fittest mares don’t reproduce while the least fit ones — the immuno-compromised — often do. Ironically, PZP selects for horses with a weak immune system.

PZP does not prevent ovulation and does not change mare behavior toward stallions. As a result, mares suffer repeated, stressful, futile breedings while the band-stallions have to battle continuously to keep their always-in-estrus mares.

Out-of-season pregnancies and births occur due to the wearing off of the drug at inopportune times. Foals born at the wrong time of year may not survive, and the mares’ health may be endangered as well.

There are reports of mares treated with PZP becoming masculinized. Previously, the reason for this effect was unknown. But in light of the new finding that PZP causes ovarian dystrophy, that would explain the masculine behavior. Much-less-than normal amounts of estrogen would be produced by the mares’ withered ovaries. Ironically, even though PZP is touted as a non-hormonal contraceptive, it appears to result in hormonal imbalance.

Mares on PZP are less faithful to their family-band, changing allegiance over and over. Such chaos disrupts normal behavior and band-membership continuity. Band-fidelity is crucial to the survival of its members, particularly the foals.

The EA indicates that BLM is aware of these adverse effects. However, by merely describing the findings of various studies, and by failing to abide by the findings that disagree with the proposed plan, BLM shows itself to be ignoring the science.

Body-Condition Improvement Could Lead to Gender-Ratio Imbalance

The EA cites a study that noted the improved body-condition of mares whose reproduction had been curtailed via PZP. This effect is cited as if it were a good thing. However, a study of mares’ body-condition and their subsequent foaling-record, showed that mares in good or improving condition tend to foal colts, while mares in poor or declining condition tend to foal fillies. The difference is significant. The researchers found that 97 percent of mares who were losing condition at time of conception foaled a filly, while 80 percent of mares who were gaining condition when they conceived foaled a colt. Therefore, PZP may correlate with an improvement in body-condition but lead to a lopsided gender-ratio favoring males


Coincidentally, a visitor to the Onaqui HMA in 2013 remarked on the obvious gender-imbalance of the horses. “It seemed to me that the sex ratio of the herd was quite skewed with many more males than females ….”


However, other studies have not found that PZP helped mares be in better body-condition. Those studies found a decline in body-condition for stallions with no improvement in body-condition for mares.

Slow Return to Fertility Acknowledged in EA

The EA cites two studies, both by the developer of PZP, that reported the average time it takes PZP-treated mares to recover their fertility. The mean is 3.7 years, but could be as long as 8 years. Because SLFO plans to contracept fillies and mares for five consecutive years, if those mares do regain fertility, they would, on average, be about 10 years old, but they could be as old as 14. This long delay could result in their perishing of natural causes before ever giving birth.

The EA goes on to note, apparently with curiosity but not concern about the risk of sterilization:

The same study demonstrated that mares treated from one to five consecutive years returned to fertility, but mares treated for seven consecutive years did not. There could be some differences seen with the Onaqui horses as they have received the experimental drug PZP -22 and the mares in the study on Assateague Island have been given just the liquid form or ZonaStat–H.
Pumas instead of PZP

What population control is superior to PZP? Pumas. There can be no “thriving natural ecological balance” without apex predators. Mountain lions, wolves, and other such carnivores effectively control wild horse populations by targeting the weak, the sick, the young, and the old. Predators ensure survival of the fittest, as Nature intends. Therefore, the best approach is for BLM to concentrate on promoting and then protecting native predators to permit natural control of the wild horse population on the range.

A puma-conservation program would tend to strengthen the herd, and it would save costs. Concerned livestock operators and nearby residents could use guardian-dogs to protect their animals. There are several specialty-breeds that have been developed just for this purpose, and they are reportedly effective. BLM might even consider buying a number of trained guardian-dogs which, per a neighboring rancher’s request, could be placed with herds or flocks experiencing attacks.

Mountain Lions Are Effective Population-Control Agents for Wild Horses

Many studies have established that mountain lions prey on wild horses more frequently than previously believed. Canadian biologists found that cougars tended to kill younger animals, especially when preying on feral horses. Nearly all of the cougars’ predation-events (86%) involved animals less than 2 years old. That would take care of those six unwanted foals.


In an interview with the Billings Gazette, the above study’s lead researcher, Kyle Knopf, described observing a cougar that brought down a feral horse in less than 30 yards from where it attacked.


Other research confirms that mountain lions are quite capable, all by themselves, of keeping wild horse populations in check. Longitudinal studies have shown that mountain lions alone successfully controlled the wild-horse population of California’s Montgomery Pass Wild Horse Territory (Turner and Morrison, 2001) and the Nevada Wild Horse Range (Greger and Romney, 1999).

Interestingly, mountain lions also used to keep the Pryor Mountain herd in check until BLM had the lions exterminated in order to experiment in managing the herd using a contraceptive pesticide.

Here is more information in regard to the research on mountain lion predation on wild horses:

The Montgomery Pass Wild Horse Territory, on the California/Nevada border, has had its ppopulation managed by cougars alone. An eleven-year study concluded that the growth of this herd was limited by cougar predation. In fact, the population actually decreased over the course of the research.


The Nevada Wild Horse Range (current designation) averaged negative population growth due to cougar predation from 1989 to 1998 (Greger and Romney, 1999).


Per The Cloud Foundation, the Pryor Mountain herd averaged no population growth over a four-year period due to predation by mountain lions. Only when those lions were killed — so that BLM could continue practicing management of the herd with PZP — did the wild-horse population begin to grow.

Healthy Predators, Healthy Ecosystems

Minimum feasible management means letting natural selection do its job. Mountain lions, wolves, bears, and coyotes should be allowed to carry out their role of population-control agents. Predators will cull the weak, and a thriving natural ecological balance will ensue. Conservation Researcher Dr. Corey Bradshaw emphasizes “… just how important predators are for healthy ecosystems. Long story short – if your predators are not doing well, chances are the rest of the ecosystem is performing poorly.”

Due to pressure from livestock and hunting interests that mistakenly view predators as pests, it has been the Federal government’s practice to exterminate native predators outright or to allow them to be hunted on a massive scale. That policy is wrong. Predators function to keep the ecosystem in balance. Without them, prey species decline, as do the forage-production species on which the prey-animals feed. Dr. Bradshaw warns: “Without predators, our feeble attempts to conserve ecosystems are doomed to fail.” Here’s the link to his timely article:


Predator Protection

The HMA should be a safe-haven for predators, which will serve as wild-horse population-control agents.

There can be no true “thriving natural ecological balance” without predators. Therefore, BLM should ensure the protection of native predators, instituting a prohibition on hunting them. Conservation measures will work to enable the right number of predators to establish themselves. Large carnivores will keep the wild-horse population in check. Such an approach would favor survival of the fittest, the best genetic adaptations, and keep the herd-populations in equilibrium with minimal human-interference, just as the Wild and Free-Roaming Horses and Burros Act envisioned. Predators are the “no-cost” option.

Recommendations: SLFO should concentrate on promoting and then protecting native predators to enable natural control of the wild-horse population on the range. A puma, bear, wolf, and coyote-protection program should be implemented. BLM should collaborate with the Utah Division of Wildlife Resources to prohibit hunting of predators in the HMA. Concerned livestock operators and residents of the surrounding area should be advised to use guardian-dogs to protect their animals. There are several specialty-breeds that have been developed just for this purpose, and they are reportedly effective. Protecting one’s herd is just part of the cost of doing business.
Onaqui Herd — Gene-Pool Changed by Introduction of Mustangs from Other Herds

The EA describes and later reiterates how SLFO has intervened over the years to inject new bloodlines into the Onaqui herd’s gene-pool:

To ensure the genetic diversity of the herd, the Salt Lake Field Office in 2005 released approximately 10 stallions and 10-15 mares from other HMA’s outside the state and from within the state. Since the large release in 2005, we have every 3-4 years released another 3-5 horses into the HMA.

Past actions that have affected the genetic diversity of the herd are: from 2005 to 2011 the SLFO has released horses from other HMA’s to ensure the genetic diversity of the herd is not lost and/or increased. In 2005 there were approximately 10 stallions and 15 mares released. Since then we have also released 3–5 mares every 3–4 years. The released horses came from other states as well as other HMA’s within Utah.

These practices evidence that SLFO’s population-management-approach is a failed strategy. If transplantation / translocation of wild horses from other HMAs — and even from other states — is necessary to support genetic viability, then the Onaqui herd is not genetically self-sustaining but is instead BLM-sustaining. Thus, SLFO is in violation of the Act and its implementing regulations by failing to provide for a self-sustaining herd.

The solution is to allow a higher population, per scientific guidelines.

BLM — Too Involved in Selecting Horses to Go, Horses to Stay

Natural selection is the way a wild-horse herd should be molded. Human-directed selection of which horses will be allowed to breed, when, and how often, interferes with natural processes. Therefore, it is cause for concern that the EA states

In the future SLFO would be proposing to do selective removals with bait trapping. While doing the bait trapping we may gather horses that we don’t want to remove. Salt Lake Field Office staff will be on site to determine if the horses caught in the trap should be removed or not.

Thus, BLM is essentially running a breeding program instead of letting Nature determine those horses best-suited for survival. This is not — and should not be — BLM’s role. Further, the projection of future removals, in spite of the ongoing, massive contraception that SLFO proposes to use on this herd, evidences that PZP does not prevent wild horses from losing their freedom.

Genetic Analysis of the Onaqui Mountain Herd

Per Section 6.1 “References Cited,” the most recent genetic analysis on the Onaqui Mountain herd was conducted seven years ago — in 2008. There have been two gathers with removals and fertility-control actions taken since then. Now, SLFO is planning intensified contraception in the absence of genetic data.

Dr. Cothran’s 2008 report was not included as an attachment, and the EA is silent as to his findings. The fact that SLFO has repeatedly imported wild horses from other HMAs and other states to increase the Onaqui herd’s genetic diversity suggests that Dr. Cothran’s analysis showed a decline in genetic variability. In such cases, Dr. Cothran typically recommends an increase in the population. However, if resources do not permit an increased population, then injecting new bloodlines is a last-ditch resort. Although the resources of the Onaqui Mountain HMA should easily accommodate a viable population, SLFO has opted to truck in horses from other HMAs. Surely this is an example of maximum meddling instead of minimal management.

Recommendations: SLFO needs to conduct a 100-percent evaluation of the Onaqui Mountain herd’s genetic health per DNA samples tested by the Equine Genetics Lab. Per those results, and per guidance from Dr. Cothran, and per consultation with wild-horse-and-burro advocates, BLM must then develop best management practices to restore and maintain gene-pool diversity via a robust population-level. An AML is valid only if it provides for an optimal population — one that can easily self-sustain its genetic viability and bounce back from random catastrophic events. Saying that the Onaqui herd must be kept “within AML” is not a meaningful statement because the current AML does not provide for a self-sustaining, genetically-viable herd. Therefore, BLM has no valid justification for contracepting any fillies or mares in the Onaqui HMA. It is not scientifically valid to contracept in ignorance — without regard to the herd’s genetics. Submitting DNA samples after-the-fact is out of order. The correct order is:

Sample first.
Sample large — 100 percent
Sample regularly — every year
Test samples.
Manage per test-results.

There should be no management-decisions made without knowledge of the genetic profile for each herd-member.

No Impacts to Genetic Diversity?

The EA makes the following claim about the effects of its PZP-plan: “No possible impacts to the genetic diversity of the herd as all horse would have a chance to reproduce.” A chance? SLFO evidently has not thought through its proposal because the PZP-plan would likely diminish genetic diversity to the point of causing the Onaqui herd to go extinct.

Half of wild foals perish before their first birthday (Gregg et al., 2014). So, the chances are 50:50 that a mare restricted to one live foal would lose her genetic contribution. If her foal were a colt, and if he did survive to adulthood, he might never sire an offspring, resulting in both his own and his dam’s genetic contribution being zero. If the foal were a filly, and if she managed to survive to adulthood, she might well already be sterile from multiple, consecutive PZP injections, resulting in both her own and her dam’s genetic contribution again being zero. At the herd-level, genetic diversity would decline steadily, as has been the case for years now. BLM’s plan constitutes management-to-extinction.

BLM — Wrong Assumptions regarding Wild-Horse Reproduction

The EA assures itself that …

Due to the relatively long time between generations (~10 years) and the long reproductive life-span of individual horses, the loss of genetic material from the herd is relatively slow and able to be monitored and mitigated by management.

Equine reproduction is indeed a slow process. If she’s lucky, a mare may produce one foal a year. Living in the wild, a mustang-mare will likely lose that foal before it reaches its first birthday. She herself may perish. All that is bad news for genetic viability at the herd-level. Hence, an optimal population is necessary. A self-sustaining herd should not need monitoring and mitigation by management.

AMLs Should Provide for Better Than MVP, but Must Provide for At Least MVP

BLM is required by law to manage the wild horses in self-sustaining herds. To be self-sustaining, a herd must be genetically viable. To achieve viability, sufficient population is necessary.

A scientifically-valid AML needs to comply with the recommendations of the International Union for Conservation of Nature (IUCN) regarding minimum-viable population (MVP) for equids. An “appropriate management level” (AML) should have a baseline — a starting point — of at least 2,500 horses. This level is the recommendation of the IUCN, the world’s oldest and largest global environmental organization. The IUCN is a neutral forum for practical solutions to conservation challenges and a leading authority on the preservation of genetic diversity in wild equids, including feral horses and burros. The IUCN notes that the selective pressures wild equids have endured in the wild are likely shaping them genetically to be hardy stock that could prove useful as a genetic resource.


Because neither the present AML nor the most-recent population-figure reaches the minimal threshold of 2,500 individuals, the Onaqui herd is under-populated. The number of horses must be increased accordingly.

Onaqui HMA — Utah — AML, and Acres per Wild Horse — Current

AML: 121 to 210 — Below minimum-viable population

BLM acres: 206,878 — which is approximately 323¼ square miles

Acres per wild horse: 1,063 – 1,610 — about 1⅔ to 2½ square miles per horse
Onaqui HMA — Utah — AML, and Acres per Wild Horse — Recommended

AML: 2,500 — Meets minimum-viable population per IUCN

BLM acres: 206,878 — which is approximately 323¼ square miles

Acres per wild horse: 83 — about 8 horses per square mile

Restore Original Onaqui Mountain Herd Area

The current HMA was carved out of a much larger herd area (HA). In that process, BLM took away 168,969 acres of wild-horse habitat. The HA needs to be reinstated as Onaqui herd habitat. The restored acres will easily support the needed increase in herd population.

Restored Herd Area acres: 375,847 — which is about 587¼ square miles

IUCN-size minimum population: 2,500 wild horses

Acres per wild horse: 150 — about 4 horses per square mile

BLM’s National Authorized Livestock AUMs

But can a restored HA of 375,847 acres sustain 2,500 or more wild horses at 150 acres per horse? Can the current HMA of 206,878 acres sustain 2,500 or more wild horses at 83 acres per horse? BLM’s approach to authorizing appropriate levels of livestock-grazing suggests the answer to both questions is “Yes”.

Below are the National statistics for authorized commercial livestock-grazing on BLM lands per animal-unit months (AUMs). Note the stocking rate: One cow or calf per 38 acres.

157,000,000 acres of public lands on which BLM allows cattle

1,033,333 cow+calf pairs that BLM permits to graze = AUMs annualized

2,066,666 cow+calf pairs per typical 6-month permit = annual AUMs x 2

4,133,332 cows and calves = pairs x 2

38 acres per cow or calf

HMAs Must Be Managed Principally for Wild Horses and Burros

HMAs are wild-horse habitat-zones. Wild horses must enjoy principal use of their HMAs. This requirement is stated plainly in the Wild and Free-Roaming Horses and Burros Act, which stipulates that their land is to be “devoted principally but not necessarily exclusively to their welfare ….” Thus, HMAs do not necessarily have to be managed exclusively for wild horses … although they can be. However, HMAs must be managed principally for the welfare of our heritage-horses.

Moreover, multiple-use does not mean every-conceivable-use. Incompatible uses can be excluded, as Secretary Jewell testified during her Senate hearing after being nominated. Some examples of incompatible uses appear obvious — mining and off-road vehicles. HMAs should be designated “no surface occupancy” (NSO) areas — to preserve aesthetic and recreational values and to avoid disturbing the horses’ natural behavior. HMAs should also be declared “off-limits” to off-highway-vehicles (OHVs) — to protect the peace-and-quiet of the range and the cleanliness of the ambient air.

Onaqui Mountain HMA is not being managed according to the Law because the wild horses are not allotted principal use of their habitat. Livestock — like locusts — devour the HMA’s resources. The wild horses have been displaced by encroaching livestock.

This inversion must be righted, and SLFO must employ the right mechanisms to do so. First, SLFO needs to rescind this EA. Then, it must amend the Land-Use Plan (LUP), Resource Management Plan (RMP), the Final Multiple-Use Decision (FMUD), and the Herd Management Area Plan (HMAP) to conform with the Law.

Disproportionate Allocation of Forage Must Be Corrected

What is wrong with this picture?

12,097 — Monthly grazing units (AUMs) allotted to livestock in the Onaqui HMA

2,252 — Maximum AUMs allotted to wild horses in the Onaqui HMA

Livestock have been awarded nearly 5½ times more grazing slots than the wild horses have been within the HMA. (Data on livestock AUMs found on pdf-page 17 of the 2012 Cedar Mountain and Onaqui Mountain Wild Horse Herd Management Areas Capture, Treat and Release Plan.) This proportionment is obviously inverted. It must be corrected. The Onaqui wild horses must receive the majority of the grazing slots — the animal unit months (AUMs) — within their HMA.

Authorized v. Actual Livestock Use

BLM may argue that actual livestock use is lower than authorized or permitted use. But because actual use is whatever the permit-holders report on Form 4130-5, and because BLM essentially takes the permit-holders’ at their word and bills accordingly … eventually … after-the-fact … maybe … or maybe not — see Bundy, Cliven — the actual-use number is unverified and likely grossly under-reported.

And what has Mr. Bundy been up to lately? Since the Federal authorities backed down, he has “really enjoyed some liberty and freedoms out here.” Translation: He continues grazing his cattle on the same public lands where he hasn’t paid grazing fees in 20 years. Reportedly, those unpaid fees are now up to $1,200,000.


Actual Grazing Use Report — Form 4130-5

As alluded to above, permittees are required to submit an annual report of how many livestock they put out on their respective allotments and for how long. Form 4130-5 “Annual Grazing Use Report” is used for this purpose. It’s a one-page document that BLM estimates to take 15 minutes to complete “… including the time for reviewing instructions, gathering and maintaining data, and completing and reviewing the form.”



Form 4130-5 is the basis on which BLM bills the permit-holders. It is also the basis for the claim of reduced-use. Thus, grazing-use is a self-reporting, self-certifying system that is rarely verified. The ease with which permittees could game the system is obvious. Consequently, the veracity of the reports is suspect.

Bundy-Supporting Permittee Grazed His Livestock beyond Authorized Use

In neighboring Nevada, permit-holder Kevin Borba, whose allotment includes land inside the Fish Creek HMA, engaged in unauthorized livestock-grazing “consistently for six months” outside the permitted use. He had his cattle out there year-round. He owes $29,410.62 in fees and fines for willful trespass, but has subsequently sued BLM over the loss of his “rights” and to stop BLM from returning any wild horses to the range following the recent gather.

Such abuses by permittees are likely widespread. Cliven Bundy and Kevin Borba are not alone in this regard. Utah has its share of rogue-ranchers too, as events last summer demonstrated.
Historical Perspective on the Onaqui Herd’s Foaling-Rate

A Google-search to find background information on the Onaqui Mountain herd happened across an entry by kbrhorse.com. The article posted at the kbr site mentioned that, in 1991, a population-survey had been conducted. That census counted 169 horses — 158 adults and 11 foals. These results suggest a foaling-rate of 6½ percent.


No PZP was used back-in-the-day, yet the natural birth-or-survival rate was below SLFO’s goal for today’s Onaqui herd. Moreover, the herd has been contracepted since 2005 with powerful and long-lasting drugs. Yet, SLFO continues to estimate its population per growth-rates that are many times higher than was the case without the drugs.

Longitudinal Study Demonstrates Growth-Rate of Five-to-Ten-Percent

The International Society for the Protection of Mustangs and Burros (ISPMB) recently completed a 14-year study of wild-horse population-growth. The ISPMB herds have been managed per the “hands-off” minimum-feasible level specified in the Wild and Free-Roaming Horses and Burros Act.

Results: Although the ISPMB alludes to a 10-percent-per-year growth-rate, to be precise, the average annual growth-rates for ISPMB’s “White Sands” and “Gila” herds were, respectively, 5.08 percent and 8.73 percent. Herd-stability and the presence of older horses appeared to be key-factors in limiting each herd’s growth-rate. It is significant that, during the study-period, there were …

No removals
No predators

Here is the link to the letter sent in this regard from ISPMB to the Department of the Interior and Bureau of Land Management.


Below is the link to a recent post by ISPMB, citing the low population-growth of the Gila Herd. From a starting-population of 31, after 14 years, it reached 100 members. That growth reflects an average annual increase of 8.73 percent.


Per this study, BLM’s assumption of a consistent 20-percent annual growth-rate is questioned.

Independent Research Discloses a Ten-Percent Foal-to-Yearling Survival-Rate

A study of BLM roundup-records for a representative sample of four herd management areas was recently published (Gregg, LeBlanc, and Johnston, 2014).


The researchers found an effective foal-to-yearling survival-rate of just 10 percent. No matter the birth-rate, what counts is survival. The same pattern likely holds true for the Onaqui herd. Yet, SLFLO’s data painted a picture of a burgeoning population.

Onaqui HMA — Population and Gather Reports — Data Sources

Per a review of the …

HMA and HA Statistics reports for the Onaqui herd from 2005-2014,
Completed Gathers reports from 2009-2014, and the
Gather-and-PZP figures reported in the EA and associated documents,

discrepancies were found.

Onaqui HMA — Utah — Herd Population Changes — 2005 to 2015

The following chart merges the yearly population-estimates with the gather and contraceptive data to reveal how the numbers were calculated and where errors were made. The beginning-of-the-year figure for 2015 — the pre-gather estimate — is per the BLM’s News Release.

January 1
Max Beginning Month
Year AML Estimate R-up Done Foal-Crop and Other Figures, Estimates
2005 210 275 August ??? No data on foal-crop even
though a post-season gather
256 Rounded up
97 Released
56 Mares inoculated with PZP-22
41 Stallions and others
159 Must have been removed
19 Assumed to have escaped
9 Tacked on for reasons unknown
125 Post-gather estimate = 97+19+9
38 Number added. Late foals?
Correction for not counting them
before the gather? Who knows.
PZP would not affect mares
already pregnant when inoculated.
163 End-of-year estimate = 125+38

2006 163 + 3 BLM estimated foal-crop @ 2%
But PZP would not affect mares
already pregnant when inoculated.
Would have contracepted mares
that were “open” in August 2005.
166 End-of-year estimate = 163+3

2007 166 + 24 BLM estimated foal-crop @ 14½%
PZP-22 at maximum effect or
still in effect, depending on mare.
190 End-of-year estimate = 166+24

2008 190 + 38 BLM estimated foal-crop @ 20%
PZP would have had residual effect.
228 End-of-year estimate = 190+38
2009 228 + 80 BLM estimated foal-crop @ 35%
October 308 Pre-Gather estimate = 238+80
218 Rounded up
184 Removed, including 2 fatalities
14 Mares given PZP-22.
9 mares retreated
5 mares treated for first time
20 Stallions, untreated mares released
90 Assumed to have escaped
124 Post-gather estimate = 14+20+90
+ 12 BLM tacked on another 12,
resulting in a combined
growth-rate of 45%.
136 End-of-year estimate = 124+12

2010 136 + 23 BLM estimated foal-crop @ 17%
… but that was per the added 12.
Foal-crop estimate per 124, with
12+23=35, would have meant 28%.
PZP would not affect mares
already pregnant when inoculated. ————————————————————- 159 End-of-year estimate = 136+23
2011 159 + 47 BLM estimated foal-crop @ 29½%
PZP was at maximum effect and
would have reduced the foal-crop.
————————————————————- 206 End-of-year estimate = 159+47

2012 206 February 186 Pre-Gather Estimate — lower by 20
155 Rounded up
34 Removed
1 Fatality
57 Mares vaccinated with PZP-22
22 mares retreated
35 mares treated for first time
63 Stallions or geldings (?) released
31 Assumed to have escaped
151 Post-gather herd per the math
57+63+31 = 151
179 Post-gather herd per 2015 EA
206 Post-gather herd per gather-report
+ 96 BLM estimated foal-crop @ 63½%
per 151 post-gather OR
+ 68 BLM estimated foal-crop @ 38%
per 179 post-gather OR
+ 41 BLM estimated foal-crop @ 20%
per 206 post-gather
PZP-22 still in effect, however.
————————————————————- 247 End-of-year estimate

2013 247 + 17 BLM estimated foal-crop @ 7%
PZP-22 at maximum effect.
264 End-of-year estimate = 247+17

2014 264 No other information available
2015 ??? No information available

The discrepancies identified herein cast doubt on the validity of the population-estimates. These errors must be reconciled before any decisions regarding birth-control or removal-actions are considered.

Societal Impact of Inflated Population-Data

The population-estimates for the Onaqui HMA are flawed, exaggerated. The political fallout of this error has been to keep the public in an uproar over an “overpopulation” that BLM’s faulty figures portrayed.

Recommendations: BLM needs to correct these errors and, more importantly, acknowledge them to the public. You must correct the record and make genuine efforts to stop this phony-story-gone-viral of a wild-horse population-explosion in Utah.

Mistakes Cost Wild Horses Their Freedom

The planned removals appear to have been hurriedly scheduled to placate the seditious elected officials and their rogue-rancher constituents, who are making a play for taking over the Federal lands in Utah. However, the wild horses must not lose their freedom merely so that BLM can kowtow to rebellious elements in the human population. If you “come clean” and admit your errors, it will tend to deflate the “head-of-steam” that the officials and ranchers are building due to the false appearance created by false figures.

Neither the First Nor the Second Time Estimates Were Found to Be Flawed

In May 2014, I submitted comments regarding the environmental assessment for Bible Spring Complex, which is located in Utah but is not under SLFO’s jurisdiction. Cedar City Field Office administers it. For the three HMAs and the one HA that compose the Bible Spring Complex, major discrepancies were disclosed — one-year growth-rate-estimates of 125%, 131%, 153%, 157%, and 249%.

Last week, I submitted comments on Cedar City’s “public health and safety” gather of over 100 wild horses from the Sulphur HMA. A review of the population-estimates for that herd disclosed that BLM had assumed an 87-percent herd-growth rate for a particular year in which PZP would have been at maximum efficacy.

A review of this EA disclosed many discrepancies that falsely made the Onaqui herd appear to be growing at implausible yearly rates. Numbers were increased arbitrarily and in spite of contraception being at full effect.

Thus, the errors uncovered across these BLM-Utah field offices regarding wild-horse population-estimates are not isolated instances. These disparities point to a systemic problem.

Recommendations: BLM needs to correct its mathematical errors and acknowledge those mistakes to the public. Elected officials, local permittees, and ordinary taxpayers need to know that the population-estimates previously announced for the Onaqui HMA were wrong. BLM must take responsibility and inform the public that it inadvertently portrayed an incorrect picture — an exaggerated picture — of the herd’s population.

1. Abandon the use of contraceptive pesticides such as PZP on the Onaqui Herd.

2. Amend the land-use plans to provide a robust AML whose low-bound is 2,500.

3. Conduct a 100-percent evaluation of the Onaqui Mountain herd’s genetic status.

4. Conserve and protect native predators, especially mountain lions.

5. Restore the acreage of the original Onaqui Mountain Herd Area.

6. Adhere to the mimumim-feasible-management requirement of the Act.

7. Administer the Onaqui HMA for the principal use of its wild horses.

8. Correct the population-estimates and advise the public how much they were inflated.



Marybeth Devlin

Miami, FL 33155

13 thoughts on “URGENT: Get your comments in by midnight against using PZP on the Onaqui mares in Utah

  1. Leave them alone PZP kills there life.If they can’t give birth then they die, I as a American citizens that pays taxes and everthing else the BLM does out of those taxes,I say HELL NO ! DON’T GIVE THE MARES OR ANYOTHER HORSE PZP IT KILLS. Thank you, founder of Wild Freedom Federation…

  2. Stop the use of PZP on our wild horses in the Onaqui herd, this is POISON AND CREATES STERILITY IN OUR MARES. Please let these magnificent horses remain free on their original AHA’s. These wild horses are a NATIVE SPECIES PROTECT THEM DON’T ERADICATE THEM!

  3. Wow! The BLM are duch sneaky liars. They are running scared. They never keep their word. PZPis meant to kill off the wild horses. It ruins the maes making them more masculine and bitchy by atrophy of their ovaries. This is ridiculous. We need our natural predators returned to the land. THEY KiLL THE WEAK AND SICK AND SOME FOALS. WHY ARE WE SPENDING MILLIONS OF dollars o f taxpayers money when the return of wolves and mountain lions could do this for free. It makes no sense. At the time the horses are not overpopulated. Between PZP and shipping them off to slaughter houses in Mexico and Canada there will be no wild horses. PZP will finish them off. Environmentally this is a huge mistake. Big money talks. The horses can not.
    We can and must. Please join this and stop the end of the Onague wild horse herd. Before

  4. I read the plan and made extensive comments but they bounced – it says there is no such email address at the BLM. Is anyone else having the same problem? Any suggestions?

  5. If PZP were used we have no chance of getting or seeing another CLOUD THE STALLION, or any other wonderful wild ones with special characteristics or markings!

  6. This is the biggest farce I believe I have heard come out of the BLM yet! I think they purposely come up with this shit and then sit back and watch us come unwind about it. They have way to much power they are not animal lovers and they are on a mission to destroy our Western Heritage by eliminating our Wild Horses. I just want to know why? What will be gained when they are gone we are close to losing them and the people in charge just don’t give a damn!!!!

  7. PLEASE!! Stop using the PZP on our beautiful WILD Horses.
    They are America’s heritage…..they are meant to be FREE!!


  8. America we don’t have a over population of Wild Horses because the Cruel BLM is still removing them as we speak. We started out with over 2 million Wild Horses, now there is only 13 thousand Wild Horses left, they are nearing complete extinction! We all must take a stand to save the only Wild Horses we have left! They never should have been tortured and removed from OUR Public Lands, the Government made a big mistake trusting the BLM to care for our Wild Horses, now they are nearing extinction and using PZP Drugs on them and this will put a end to our Wild Horses forever. PZP Drugs causes weight loss, birth defects, sterilization and it causes so much fighting within the herds.as they want to breed and the mares don’t want to, they can really hurt each other fighting and many times the baby foals get accidently kicked and killed. Why are we even using PZP when the BLM mentioned they could not even hardly afford it because it was very expensive, our tax dollars at work again!! The use of PZP is also another scam the BLM is using to buy more time to finish off all their evil plans of more roundups. The BLM is busy buttering up the Wild Horse Advocates, creating a bond with them as it is a good way to distract the negative attention away from the BLM so they can continue to torture and finish up with their Abomination of America’s Wild Horses!!!! Let them be!!! No more drugs, No more cruel BLM Roundups!!!!
    Tina Wooten for saving and restoring our Wild Horses and returning to their rightful freedom!!! STOP BLM NOW!!!!

  9. What will we leave our children? McDonalds instead of wild horses? Stop this please!

  10. Whenever human beings try to control nature for their own purposes, it is a disaster. The key is to leave the horses, the predators, the land alone. Remove the cattle, the frackers, the oil rigs, etc. This world will survive without us and not even miss us.

  11. Welfare over heritage? Forcing sterilization and violent round ups of an iconic national symbol? Is this what America has become? Cruel destruction of our wild horse family’s for greedy corporate sourcing of cheap welfare rancher meat? How twisted and sick is the priority? Ranchers can buy land, own a ranch and sell a product for a premium. Stop giving access to public lands for welfare ranchers and having the so called blm clear our land on our fine for welfare ranchers. This is not management, this is abuse and corruption against the will of Americans and our horses belong on this land. Leave our horses alone and stop giving our land and iconic beautiful wild horses death sentences for welfare meat. Sending our horses to slaughter and sterilizing them is criminal, and this is absolutely against the will of this nation. The blm is a dirty little organization full of dirty practices. It manages with one purpose only, clear the lands of horses.

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