ePlanning DOI-BLM-ORWA-B050-2019-0013-EA (Spay Feasibility and On-Range Outcomes Environmental Assessment)  
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05/30/2019 14:52:39 MDT
FREQUENTLY ASKED QUESTIONS (last updated May 10, 2019)
Describe the project.
The EA analyzes a proposed action to evaluate the safety, complication rate, and feasibility of ovariectomy via colpotomy (spay) on wild horse mares and to allow the United States Geological Survey (USGS) to evaluate the impacts of spaying on mare and herd behavior once returned to the range as compared with an untreated herd.  The study would use wild horses gathered from Warm Springs Herd Management Area (HMA) in October 2018.
This proposed action is very similar to one proposed in the Spay Feasibility and On-Range Behavioral Outcomes Assessment and Population Management Plan for Warm Springs Herd Management Area EA from 2018 (DOI-BLM-ORWA-B050-2018-0016-EA). A Decision Record to implement portions of that EA was vacated in November 2018. BLM, through this new EA, is now analyzing an updated approach to addressing the horses gathered in October 2018.
The main difference between the proposed action from the 2018 EA and the proposed action in this EA is that the mares being treated with ovariectomy via colpotomy for the study would not be pregnant. Otherwise, all aspects of this proposed BLM spay feasibility study and USGS on-range behavioral outcomes assessment would be the same as those proposed in 2018.
Why is the BLM proposing this project?
In a June 2013 report, the National Academy of Sciences found that no highly effective, easily delivered and affordable fertility-control methods were currently available to manage wild horse and burro populations; the NAS urged the BLM to use better research tools. On March 6, 2014, BLM issued a public request for applications for research proposals “aimed at developing new or refining existing techniques and establishing protocols for the contraception or permanent sterilization of either male or female wild horses and/or burros in the field. This project is one of those proposals.
Since receiving Federal protection in 1971, wild horse and burro populations on public lands have soared, far exceeding what is healthy for the land and the animals. With virtually no natural predators, herds can double in size in just four years.  As of March 2018, the BLM estimated public rangelands were home to nearly 82,000 wild horses and burros, which is more than three times what the land can sustainably support in the long term (the recommended number is 26,690 animals). In 2017 alone, the population grew by more than 9,000 animals.
The adverse impact of these soaring populations is tremendous. Not only does overgrazing damage the land, but more animals are susceptible to starvation and thirst. Public safety is also put at risk as animals move onto highways and private property in search of forage and water. This project is part of BLM’s efforts to achieve long-term sustainable populations on the range in a humane manner.
Didn’t the BLM already try this project with Oregon State University in 2016, and then again with Colorado State University in 2018?
Following BLM’s 2014 request for proposals, BLM awarded funding to Oregon State University (OSU) to investigate the safety and efficacy of three separate methods of surgical sterilization of wild mares previously removed from the range. This project was to occur at the wild horse corrals on Burns District in Oregon. Burns District received several district court lawsuits and administrative appeals upon issuing the decision record to implement the research project with OSU, including a plaintiff’s claim they had the right to observe the surgeries under the First Amendment of the U.S. Constitution. Ultimately, the OSU researchers withdrew from the project as BLM was advised to provide public observation of all aspects of the research. This project was subsequently cancelled.
Colorado State University withdrew from the 2018 proposed project, stating: “After careful consideration of multiple factors during the 30-day public comment period for the Warm Springs, Oregon, mare spay project, Colorado State University is withdrawing our partnership on the surgical spaying of mares. The project is led by the Bureau of Land Management and USGS. The decision to withdraw was made with the support of our involved researchers. Although we withdraw from this particular effort, wild horse and burro overpopulation is a critical animal welfare issue that must be solved through objective, collaborative and transparent research. Our efforts include multiple approaches to solving this problem. Examples are the just released results of an eight-year study that provides initial, promising information about a birth control vaccine protocol for use in wild mares, and our ongoing research in observing wild horse behavior among overpopulated bands across the West. As an academic institution, we are committed to exploring this important animal welfare concern. We will continue to pursue alternatives that address wildlife welfare issues, leaving the door open to our future work.”
What is the difference between the current proposed project and the project proposed with CSU?
The goals of the proposed projects remain the same – to assess the feasibility of using the procedure ovariectomy via colpotomy to spay wild horse mares, and to assess the behavior impacts on the individual, band and herd of spaying wild mares and returning them to the range. The BLM intends to conduct the spay procedures using the same safe and humane methods as were originally proposed and approved through CSU’s Institutional Animal Care and Use Committee. The main difference between the proposed action from the 2018 EA and the proposed action in this EA is that the mares being treated with ovariectomy via colpotomy for the study would not be pregnant. Otherwise, all aspects of this proposed BLM spay feasibility study and USGS on-range behavioral outcomes assessment would be the same as those proposed in 2018.

What does ovariectomy via colpotomy mean?
Ovariectomy via Colpotomy directly translates to removal or the ovary or ovaries by way of an incision in the vagina.  
  • This technique has been in use for over 100 years on domestic horses.
    The procedure takes approximately 15 minutes per mare.
    It is performed under standing sedation.
    There are no external incisions that could increase the risk of infection.
    Only the ovaries are removed.
    Only approximately one week of recovery time is needed before the mare can be returned to the range.
    Previous use on feral mares shows less than 2% mortality rate associated with the procedure.
    The cost per mare is less than one dose of PZP-22 (less than $300).
    No follow-up treatment is necessary for the life of each mare.
What does it mean to “spay” a wild horse mare?
The term “spay” is readily understood by the American public as a way to prevent pregnancy in female animals. A typical “spay” involves abdominal surgery to remove the ovaries and uterus. An ovariectomy via colpotomy is less invasive than a typical “spay” in that it includes only one small internal incision and removes only the ovaries (not the uterus).
What steps will BLM take to ensure the procedure will be safe and humane?
Licensed veterinarians experienced in ovariectomy via colpotomy and standing sedation on wild horse mares will conduct the procedures. The same procedure protocol would be conducted that was previously approved by CSU’s Institutional Animal Care and Use Committee. Mares will be sedated (standing) and receive local anesthesia and pain relief medication. The BLM will follow veterinarian guidance to ensure that the areas near surgeries are clean. To minimize the risk of infection, no external incisions will be made. Animals will be monitored after the procedure for signs of discomfort for up to seven days. Any mare showing signs of post-operative complications will receive treatment as recommended by a veterinarian.
Why sterilize mares instead of gelding stallions?
BLM has mainly relied on a female-based contraception and sterilization approach because there is a direct relationship between the number of fertile females and the number of foals. Each adult mare typically has a foal every year or every other year. Every year that a mare is successfully contracepted translates to approximately one less foal being born. Permanently sterilized mares would be prevented from giving birth to many foals over their lifetime.
With vasectomy or gelding, there is little to no expected reduction in growth rates until a critical threshold in the percentage of stallions treated has been reached – although this exact number is unknown, according to one peer-reviewed research paper, 80% or more of stallions may need to be treated in order to stabilize wild horse populations just due to the fact that a single stallion can impregnate many mares on the range. Logistically and financially, this is not practical. In one well-studied herd, about 14 percent of stallions with a harem were 4 years old or less when they first held their harem. Therefore, to reliably prevent males from impregnating mares, BLM would need to conduct gathers every 3 years just to geld or vasectomize nearly all the young males.
Can’t the BLM just reduce or remove livestock from the range to allow room for more horses?
Wild horse populations increase at an average of 20 percent annually, causing the herd to double in size within 4-5 years. Simply removing authorized livestock would not solve the problem of reducing the annual population growth rate of wild horses. Our arid to semi-arid western rangelands can only produce so much forage and provide limited water for all uses; livestock, wildlife and wild horses and burros. BLM must manage for healthy populations of wild horses and burros in a thriving natural ecological balance (WFRHBA 1971) and multiple-use relationship (FLPMA 1976) on public lands.
Because they have no natural predators capable of controlling herd sizes, wild horses and burros will always need to be managed on public lands in order to stay healthy, regardless of whether there is livestock in a given area or not. Even in areas where there is no livestock grazing, we have found that wild horse herds grow at 15-20 percent every year and still need to be managed so herds do not grow too large for the available water and forage. Simply removing other users of the range, including livestock or wildlife would only make the challenge even bigger down the road. 
Who is/are the veterinarian(s) completing the ovariectomies?
The veterinarians involved with this proposed project are extremely experienced with large animal surgery, with decades of experience. In keeping with the Privacy Act of 1974, the government is not authorized to release the names of private individuals involved with this proposed project.
Do spayed mares lose their natural behavior?
This procedure was conducted on 114 feral horse mares at the Sheldon National Wildlife Refuge between 2008 and 2014. The research report showed treated horses maintained group associations and there were no differences between survival rates for released animals with treatment compared to those untreated. 
There is little other scientific analysis of the behavior effects of spaying a portion of a wild herd. This project would provide BLM with valuable information on the behavior effects of having spayed mares in a wild horse herd as compared to a non-treated herd. Spaying a portion of a wild horse herd could be a viable tool to manage population growth on the range. By developing better tools to manage population growth on the range, fewer horses would need to be removed to control population growth and maintain ecological balance on public lands. A similar study evaluating the effects of neutering (gelding) a portion of a wild herd is currently taking place in Utah.
Why doesn’t BLM just use more PZP for population growth suppression?
Two versions of the PZP vaccine are currently in use. One version, known as Zonastat-H, is implemented through ground-darting programs and is only effective for approximately one year. The second version, known as PZP-22, is effective for 1-2 years but must be hand-injected into a captured wild horse. A majority of HMAs across the West are extremely large (500,000+ acres), have limited access during late winter or early spring (when the vaccine should be applied to be effective), and do not have horses that are approachable by humans within 50 yards for darting of fertility control vaccine – these reasons make remote delivery (darting) of individual mares in most herds technically infeasible.  Longer lasting formulations of PZP (PZP-22) have not proven effective at population growth suppression on a majority of HMAs where it has been applied. Annual gathering of the entire herd for application of fertility control vaccine is economically infeasible due to associated gather costs (nearly $3,000 to catch-treat-release one mare and associated stallion). In addition, repeated captures could increase the risk of injury or death to individual animals.
Are there other research projects proposed or in progress regarding wild horse population management?
The BLM is currently developing and studying a variety of methods to support wild horse population management, including contraceptives and other procedures. Details are here:
How can I submit a comment?
The EA and unsigned FONSI are available at https://eplanning.blm.gov/epl-front-office. This link takes you to BLM’s ePlanning website.  To search for the EA and unsigned FONSI you can either use the map to locate Burns District, Oregon or click on the “Text Search” tab.  In the “Text Search” tab select from the drop down menus:
            State: Oregon/Washington
            Office(s): ORWA – Three Rivers FO
            Document Type(s): EA
            Fiscal Year(s): 2019
            Program(s): Wild Horses and Burros
            Click “Search”
If you have comments on the updated EA or unsigned FONSI, submit them postmarked by May 25, 2019, to Spay Project Lead, Burns District Office, at 28910 Hwy 20 W, Hines, Oregon 97738.  Email comments should be sent to: blm_or_bu_spaystudy@blm.gov
What is the cost of spaying vs. say PZP treatment?
Ovariectomy via colpotomy costs approximately $250–$300 per mare. The cost includes the expense of the antibiotic ($30 per dose), the sedation drugs, and the veterinarian’s labor and travel. PZP-22 fertility treatment costs approximately $500 per mare treated. This includes the costs of one dose liquid primer (similar to ZonaStat-H used for remote darting) and one dose time-release pellets; plus holding and application costs – approximately $5 per day per horse.  ZonaStat-H (used for remote darting) costs approximately $35 per dose.  
Could this be a “test” case for other HMAs?
This project will evaluate the safety, complication rate and feasibility of ovariectomy via colpotomy on wild horse mares and the impacts to mare and band behavior once returned to the range as compared with an untreated herd. Ovariectomy via colpotomy could be an effective tool for managing population growth on the range. This study represents a feasibility approach, and the results are not policy setting for BLM. Any future proposal by BLM to utilize the spay method analyzed in this EA would be subject to NEPA compliance.
What are the long-term expectations for genetic diversity with a slower-growing and more limited population?  
It is true that spayed mares are unable to contribute to the genetic diversity of a herd, but that does not lead to an expectation that the Warm Springs HMA would necessarily experience high levels of inbreeding because 1) there would continue to be a core breeding population of mares present, 2) there was high genetic heterozygosity in the herd at the last measurement, 3) horses could always be introduced to augment genetic diversity if future monitoring indicates cause for that management action, and 4) there is an expectation of continued positive growth in the herd. The Warm Springs HMA would have only a low risk of loss of genetic diversity because the proposed action incorporates BLM's management plan for genetic monitoring and maintenance of genetic variability.
** It is worth noting that, although maintenance of genetic diversity at the scale of the overall, population of wild horses is an intuitive management goal – there are no existing laws or policies that require BLM to maintain genetic diversity at the scale of the individual HMA or complex.
Would there be any chance of selective breeding in this plan?
The Three Rivers Resource Area Management Plan (1992) directs the BLM to enhance and perpetuate the special or rare and unique characteristics that distinguish a particular herd. Color, type, conformation, distinctive markings, size and weight of members are characteristic of the historic background of horse herds and it is highly desirable to retain this important linkage. Horses in the Warm Springs Herd Management Area are historically saddle-type in a variety of colors, but with emphasis on Appaloosa, between 14 – 16 hands and 950 – 1,300 lbs. High quality mares and stallions of or near this description will be selected for return to the range. This management practice has been in place and effective for decades.   

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