U.S. DEPARTMENT OF THE INTERIOR  BUREAU OF LAND MANAGEMENT  
ePlanning DOI-BLM-ORWA-B050-2018-0016-EA (Spay Feasibility and On-Range Behavioral Outcomes Assessment and Warm Springs HMA Population Management Plan)  
> NEPA Register > DOI-BLM-ORWA-B050-2018-0016-EA > FAQs
  
Find Whole Words Only
Home
Documents
Contact Information
How to get Involved
    Meetings
Maps
    Data
Links
FAQs
Last Updated:
09/12/2018 15:16:04 MDT
FAQs 
FREQUENTLY ASKED QUESTIONS
FREQUENTLY ASKED QUESTIONS - Last updated: September 12, 2018

Describe the project.
Burns District Bureau of Land Management (BLM) is proposing a wild horse “Spay On-Range Behavioral Outcomes Assessment” research project under an assistance agreement with the United States Geological Survey (USGS). The Burns District BLM proposes to evaluate the safety, complication rate, and feasibility of ovariectomy via colpotomy (spay) on wild horse mares and to allow the USGS to evaluate the impacts of spaying on mare and band behavior once returned to the range as compared with an untreated herd. A 10-year population management plan is also included in this EA.

What is the BLM’s decision on this project?
The BLM’s decision is to implement the following actions as described in the EA:
1) The Spay Feasibility and On-Range Behavioral Outcomes Assessment (2018-2022), and,
2) The portions of the Population Management Plan that provides direction on gathering wild horses in 2018.
 
The spay study will allow BLM to evaluate the safety, complication rate, and feasibility of ovariectomy via colpotomy on wild horse mares and USGS to evaluate the impacts to mare and band behavior once returned to the range as compared with an untreated herd.
 
When will this decision be implemented?
Due to escalating conditions related to limited water availability in the HMA and deteriorating conditions of the natural surface roads presently being used for hauling water, implementation of the wild horse gather will begin in early October 2018 followed by the spay study. 

Can I observe the gather?
Observation will likely be held daily, on a first come, first served basis. Every effort will be made to accommodate everyone interested each day, however, participation may be limited and/or some days of the gather may not provide a viewing opportunity due to variable circumstances such as moving the trap location (not gathering), no safe area to view activity or disguise vehicles, rainy or windy conditions (not gathering), poor vehicle access, etc. Notice on the days where no viewing opportunity exists will likely be given on short notice – perhaps the day before or the morning of the gather operation. You may attend multiple, consecutive observation days as long as you are within the first come, first served maximum (if one is set). 

Observers must first attend a pre-viewing briefing at the BLM Burns District Office, 28910 Hwy 20 West in Hines. The date and time of this briefing will be announced on the gather web site as soon as it is determined. Observers arriving at the viewing area without first attending the briefing shall not participate in the observation day. 

Access to and distance from the capture site location will be determined jointly by the Contractor and the BLM's Contracting Officer's Representative prior to gather operations. Safety of the horses, crew and public, is our top priority.


Why is the BLM proposing this project?
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.
 
What is the difference between the 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.
 
Why is the BLM moving forward on the project after CSU withdrew?
On August 8, Colorado State University withdrew from the proposed project to evaluate a safe and humane method of spaying wild horses in Oregon’s Warm Springs herd, where the wild horse population is rapidly outgrowing the available water resources and is faced with a growing risk of death from water starvation. In confronting the challenge of chronic overpopulation in the Warm Springs herd, the BLM remains committed to implementing a variety of management practices that include a safe and humane way to spay wild horses. We look forward to partnering with U.S. Geological Survey to assess behavior impacts of spayed mares after they have been returned to the Warm Springs herd management area.   
 
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.
 
Can I observe the procedures as they occur?
Public observation of the collaring/tagging and spaying will be available at the Oregon Wild Horse Corral Facility. Those interested must contact Burns District BLM Public Affairs Specialist, Tara Thissell (tthissell@blm.gov or 541-573-4519) after October 15 to be added to the viewing list. Observation will be offered to those on the viewing list on a first come, first served basis, in the order interest was expressed in attending (starting on October 15). The actual dates for spay viewing will be announced as soon as they are determined.
 
The spay viewing area in the working barn only provides space for five observers at a time.  If additional observers are interested in viewing per day, viewing could occur in shifts with observers rotating through every two to four hours. Visitors will be escorted at all times and prohibited from the working area while horses are present.


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. (Collins and Kasbohm 2016 – Population Dynamics and Fertility Control of Feral Horses).
 
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:
https://www.blm.gov/programs/wild-horse-and-burro/herd-management/science-and-research
 
How long will it take to review the comments and issue a decision?
 A decision was issued September 12, 2018.
 
How soon could the project begin? 
The project could begin as early as mid-October.
 
Do public comments and decision determine if the project takes place?
Comments do not determine if a project will take place or not. Comments are meant to convey public support or concern and the specifics of those opinions, as well as evidence suggested alternatives or other means to accomplish the project needs. The decision, which is issued by the BLM, will articulate how we intend to move forward with the project. That decision could be appealed by a person or group in opposition of the project. If this happens, the timeline of project implementation could be determined by the courts and/or agency policies depending on the nature and content of the appeal.
 
Is there a breeding season for wild horses (a time of more conceptions that other times of the year)?
A majority of mares are pregnant when gathered after July 1 of any year. The average mare gestation period ranges from 335 to 340 days (Evans et al. 1977). There are few peer reviewed studies documenting the effects of ovariectomy on the success of pregnancy in a mare. A National Research Council (NRC) committee that reviewed research proposals in 2015 explained, “The mare’s ovaries and their production of progesterone are required during the first 70 days of pregnancy to maintain the pregnancy” (BLM 2015). In 1977, Evans and others stated that by 200 days, the secretion of progesterone by the corpora lutea is insignificant because removal of the ovaries does not result in abortion (p. 376). “If this procedure were performed in the first 120 days of pregnancy, the fetus would be resorbed or aborted by the mother. If performed after 120 days, the pregnancy should be maintained. The effect of ovary removal on a pregnancy at 90–120 days of gestation is unpredictable because it is during this stage of gestation that the transition from corpus luteum to placental support typically occurs”
(BLM 2015). 
 
For those pregnancies that are maintained following the procedure, likely those past approximately 120 days, the development of the foal is not expected to be affected. However, because this procedure is not commonly conducted on pregnant mares the rate of complications to the fetus has not yet been quantified. There is the possibility that entry to the abdominal cavity could cause premature births related to inflammation. However, after five months the placenta should hormonally support the pregnancy regardless of the presence or absence of ovaries. 
 
It will be important to understand how gestational stage affects the surgical procedure and how the surgical procedure affects maintenance of pregnancy.  
 
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.
 
 
 
No content is currently available for this page. Please click the links to the left for more project information.