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An Overview of Wild Horse and Burro Management in the American West – 3.104   arrow

By Hailey Doucette, Dr. Leisl Carr Childers & Retta Bruegger

Quick Facts…

  • Wild horse and burro populations can grow by 20-25% per year.
  • Management of wild horses and burros falls primarily to the Bureau of Land Management and is governed by the 1959 Wild Horse Annie Act, the 1971 Wild Free-Roaming Horses and Burros Act, and the 1976 Federal Land Policy and Management Act.
  • Wild horse and burro populations are exclusively located in the American West.
  • Current numbers of wild horses on public lands in the US far exceeds the carrying capacity of these lands.
  • Aligning horse and burro populations with sustainable range management goals requires funding and personnel.

Introduction

The management of wild horses and burros is a controversial topic in the American West. Wild horse and burro populations must be managed to prevent too many animals from causing damage to public rangelands like soil erosion and loss of grasses and other forage, which negatively effects wildlife and the livelihood of those who also use these lands. This fact sheet covers the laws that protect wild horses and burros, discusses key terms and how wild horse and burro populations are managed, and what happens to wild horses and burros when they are removed from public rangelands.

Laws Protecting Wild Horses and Burros

Wild horses and burros populate areas in the arid American West that contain limited forage and water. Though their numbers grew during early history of the region, they dwindled throughout the first half of the 20th century when ranchers, hunters, and mustangers rounded up unwanted wild horses and burros for extra income, often selling them to slaughterhouses. In 1950, Velma Bronn Johnson, better known as Wild Horse Annie, and other wild horse advocates began a campaign to protect wild horses and burros (1). Their efforts resulted in the 1959 Wild Horse Annie Act, which banned the poisoning of watering holes and the use of motorized vehicles in hunting and capturing wild horses for sale and slaughter. The law did not include Johnston’s recommendation to create a federal program to protect, manage, and control wild horses and did not include burros (2). 

After a massive public campaign to grant wild horses and burros protection on public lands, in 1971 Congress passed the Wild Free-Roaming Horses and Burros Act. The act stated: “wild free-roaming horses and burros shall be protected from capture, branding, harassment, or death; and to accomplish this they are to be considered in the area where presently found, as an integral part of the natural system of the public lands (3).” 

Most wild horse and burro populations ranged on lands managed by the Bureau of Land Management (BLM), though some also could be found on Forest Service lands. As a result, the BLM is the predominant land management agency tasked with managing wild horses and burros. The BLM received its official mandate from the 1976 Federal Land Policy and Management Act (FLMPA). 

Map featuring the locations of HAs, HMAs, and
Ranges.

This mandate instructs the BLM to manage public lands for multiple uses, such as mining, energy development, livestock grazing, timber harvesting, outdoor recreation, wildlife protection, and historical resources, in addition to protecting wild horses and burros (4). This means that the BLM must manage all of these uses in relationship to each other. The BLM had managed all these multiple uses before 1976, but FLPMA made it official. This mandate instructs the BLM to manage public lands for multiple uses, such as mining, energy development, livestock grazing, timber harvesting, outdoor recreation, wildlife protection, and historical resources, in addition to protecting wild horses and burros (4). This means that the BLM must manage all of these uses in relationship to each other. The BLM had managed all these multiple uses before 1976, but FLPMA made it official. 

Wild horse, and burro populations grow rapidly if left alone. A herd of wild horses can increase by 20-25% every year. For example, a herd of 100 wild horses on public rangelands would increase to 200 wild horses within four to five years (5). The BLM limits the number and amount of time livestock spend on public rangelands and expects ranchers to adhere to those limits. The overall number of livestock on BLM rangelands has steadily declined since the 1960s, remained about constant 1980s to 2000 and declined again 2000-present (6). Similar to livestock, the BLM sets limits on the number of wild horses and burros. However, unlike livestock, wild horses and burros occupy these rangelands year-round and their populations have increased. Greater populations and their presence on rangelands year round does not always allow for regrowth of sparse forage, especially in dry years. This means it is very important to keep wild horse and burro populations to levels rangelands can support. To do this more easily, FLMPA amended the 1971 law to allow the BLM to use helicopters when gathering wild horses and burros (7).

How the BLM Manages Populations

Because of its multiple use mandate, the BLM cannot manage wild horses and burros without taking into consideration the needs of other animals that rely on the forage resources on public lands, specifically wildlife, and livestock that the BLM permits to graze on public lands. The Public Rangelands Improvement Act of 1978 required the BLM to set AMLs for wild horses and burros on public lands with respect to wildlife and livestock (8).

When wild horse and burro populations exceed their AML in an HMA, extreme damage to the rangelands can occur. Wild horses and burros, wildlife, and livestock all compete for the same forage and water. Too many of any of these animals too long in one place can deplete the available resources, which is why managing all their populations is crucial (9).

The number of wild horses and burros on
rangelands compared to the Animal
Management Level (AML) based on 2020
numbers.
Exponential growth represented in tens of animals
over five years.

The BLM manages wild horses and burros differently than livestock and differently than states manage wildlife. Natural predation limits wildlife numbers and state wildlife officials supplement reductions by issuing hunting permits for certain species such as elk and deer to maintain their populations in an acceptable range. The BLM caps the number of livestock it permits ranchers to graze on public rangelands based on the average amount of forage produced in their grazing area. Ranchers given BLM grazing permits are responsible for grazing only the permitted number of animals. With wild horses and burros, the BLM sets an acceptable population range, the AML, for a particular area. When the maximum population is exceeded, the BLM is responsible for lowering those numbers. Because the population of wild horses and burros doubles every four to five years, gathers should occur often. Small gathers of 0-10 can be done using bait, which is less expensive and less stressful on the wild horses and burros. 

Larger gathers require motorized trapping operations that are expensive and stressful on the herds (10). 

The BLM does have other methods of controlling wild horse and burro populations. Currently, Porcine Zona Pellucdia (PZP) and GonaCon-Equine are drugs that suppresses fertility in wild horses and burros and are available for the BLM to use (11). These drugs are expensive, and both require the BLM to dart the mares in each herd, sometimes once, sometimes more than once each year.

The agency uses volunteers to help distribute fertility control among herds. When both fertility control and small gathers are used together, these methods can help maintain the AMLs over longer periods of time by limiting the number of animals born each year. 

BLM Photo: BLM Colorado State Director Ruth Welch
(center) joins members of the Little Book Cliffs Darting
Team to view horses at the Little Book Cliffs.

One example of successful wild horse management is in the Little Book Cliffs Wild Horse Range near Grand Junction, Colorado (12). Friends of the Mustangs, a 501 (c) 3 non-profit volunteer group, has assisted the BLM since 1982 with the Little Book Cliffs Wild Horse Range. Volunteers help improve range conditions, including bettering established water sources, reseeding burn areas, and replacing fencing. In 2002 they formed the Little Book Cliffs Wild Horse Range Fertility Control Darting Team to administer PZP to Little Books Cliffs horses. PZP administration reduces the number of foals born each year and is a large part of the reason gathers in this HMA are smaller and less frequent.

What Happens to Wild Horses After Gathers

Meeker Mustang Makeover Photo: 2020 judges (left
to right) Mindy Bower (UhOh Ranch), Steve Mantle
(Mantle Ranch), and Bridget Strang (Strang Ranch).

The BLM works to place gathered wild horses and burros into private care through the agency’s adoption program. Adoptions allow individuals to acquire a wild horse or burro, but only if they meet certain requirements and adequately care for the animal for one year. In recent years, approximately 3,000 wild horses and burros were adopted each year (13). When a wild horse or burro is over ten years old or has been offered for adoption at least three times it is eligible for sale. A sale is different from adoption because the ownership of the horse passes directly to the buyer at the time of the sale (14). 

Adoptions and sales are often facilitated by programs such as the Meeker Mustang Makeover, Wild Horse Inmate Program (WHIP) in Cañon City, Colorado, and the Trainer Incentive Program (TIP). Makeover events for wild horses such as the Meeker Mustang Makeover give trainers a set amount of time to train a wild horse. At the end of that time, the program holds a competition displaying the strengths of each horse, and buyers can bid on them for adoption (15). WHIP is a partnership between Colorado Correctional Industries and the BLM in which wild horses are trained by inmates and professional horse trainers and then can be adopted by qualified buyers (16). 

The total BLM Wild Horses and Burros program budget based on FY 2019 figures.

The Mustang Heritage Foundation, which also hosts the Extreme Mustang Makeover, created TIP “to bridge the gap between the public and excess wild horses in off-range corrals.” TIP is a network of horse trainers who train and find homes for wild horses (17).

Although adoptions and sales are important, most wild horses and burros gathered by the BLM are placed in long-term off-range holding facilities. As of the spring of 2020, the BLM estimated there were more than 95,000 wild horses and burros on public lands. The BLM has set the total AML for wild horses and burros across all the HMAs at just under 27,000. This means that 68,000 excess wild horses and burros are on public lands. An additional 47,845 wild horses and burros are being held in long-term off range holding facilities. Caring for wild horses and burros in these off-range holding facilities costs the BLM around $27.6 million each year (18).

Conclusion

Wild horses and burros are a fundamental part of the BLM’s multiple use mandate. But the BLM is faced with a difficult situation. The number of wild horses and burros on public rangelands far exceeds established AMLs and there are tens of thousands of additional animals in long-term off range holding facilities that the BLM funds. For management to work well, the BLM has to create a situation in which the numbers of wild horses and burros on public rangelands are commensurate with AMLs and there are minimal animals in long-term holding facilities. To do this, the BLM needs to conduct more gathers and fund more long-term off-range holding facilities in the short term to reduce populations on the rangelands. 

Over the long-term, the BLM needs more funding and personnel to conduct more frequent, smaller gathers, and pay for and administer fertility control treatments. The BLM receives the least amount of federal funding of all the public lands management agencies and has the smallest staff. This means the agency relies on volunteer groups and working partnerships with organizations like Friends of the Mustang and Piceance Mustangs (19) to help manage wild horses and burros both on and off public lands. Wild horses and burros have a place on the nation’s rangelands, but the BLM needs the funding, volunteers, and popular support to manage them well.

Key Management Terms

Wild horses and burros are protected in specific areas and according to specific management plans. Below are some key terms the BLM uses in its management. 

Herd Area (HA): 

HAs are federal lands that had wild horse or burro populations when the 1971 Wild Free Roaming Horses and Burros Act passed. HAs have multiple uses, but for a variety of reasons, the BLM may not be able to manage them for wild horses and burros.

Management Area (HMA): 

HMAs are areas within HAs where the BLM manages wild horses and burros in balance with other uses such as livestock grazing, which the agency also manages, and wildlife, which states manage. HMAs are areas that can support the long-term management of wild horses and burros. In HMAs, the BLM applies specific laws and regulations pertaining to the management of wild horses and burros. 

Wild Horse Range: 

Wild horse ranges are HMAs the BLM manages principally for wild horses. There are only 3 wild horse ranges in the United States: the Nevada Wild Horse Range in Nevada, the Pryor Mountains Wild Horse Range in Montana, and Little Book Cliffs Wild Horse Range in Colorado. Livestock grazing does not occur on wild horse ranges. 

Appropriate Management Level (AML): The AML is the number of wild horses or burros in an HMA that the BLM determines the land can support in balance with other multiple uses. The BLM sets AMLs between a minimum and a maximum number. 

Animal Unit Month (AUM): 

AUMs are the number of animals relative to the feed available in a particular area over the course of one month. The BLM calculates AUMs based on the amount of forage a single animal needs to thrive in a single month. 

Multiple Use: 

The BLM’s mission established by the 1976 Federal Land Policy and Management Act instructs the agency to manage public land resources for a variety of uses, such as wild horse and burro protection, mining, energy development, livestock grazing, timber harvesting, outdoor recreation, wildlife protection, and historical resources. Multiple uses are not necessarily equal. Rather, they are balanced in relationship to each other. 

Citations

1. Alan Kania, Wild Horse Annie: Velma Johnston and her Fight to Save the Mustang (Reno, Nevada: University of Nevada Press, 2012), 7. 

2. The Wild Horse Annie Act, American Wild Horse Campaign, Accessed August 7, 2020,  https://americanwildhorsecampaign.org/wild-horse annie-act 

3. Wild Free Roaming Horses and Burros Act of 1971 (Public Law 92-195) s. 1331, https://www.blm.gov/or/regulations/files/whbact_1971. pdf 

4. A Multiple-Use and Sustained Yield Mission, Bureau of Land Management, Accessed August 7, 2020, https://www.blm.gov/about/our-mission James Muhn and Hanson Stewart, Opportunity and Challenge: The Story of the BLM, September 1988, Accessed August 7, 2020, https://www.nps.gov/parkhistory/online_books/blm/hi story/chap4.htm 

5. Subcommittee on Public Lands, Forests, and Mining, Senate Energy and Natural Resources, U.S. Department of the Interior, Bureau of Land Management, Deputy Assistant Director Resources and Planning, Steve Tyron, Wild Horses and Burros: Long Term Management Options for the Bureau of Land Management’s Wild Horse and Burro Program, July 16, 2019, Accessed August 7, 2020, https://www.doi.gov/ocl/wild-horses-and-burros 0#:~:text=Since%20wild%20horses%20have%20virtu ally,remove%20them%20from%20the%20range 

6. John E. Mitchell, “Rangeland Resource Trends in the United States: A Technical Document Supporting the 2000 USDA Forest Service RPA Assessment,” Fort Collins, CO: Rocky Mountain Research Station, 2000 (64-68). Accessed October 29, 2021, https://www.fs.fed.us/rm/pubs/rmrs_gtr068.pdf. Tay Wiles and Brooke Warren, “Federal-Lands Ranching: A Half-Century of Decline,” High Country News, June 13, 2016. Accessed October 29, 2021, https://www.hcn.org/issues/48.10/federal-lands grazing. 

7. James Muhn and Hanson Stewart, Opportunity and Challenge: The Story of the BLM, U.S., September 1988, Accessed August 7, 2020, https://www.nps.gov/parkhistory/online_books/blm/hi story/chap4.htm 

8. National Research Council, Using Science to Improve the BLM Wild Horse and Burro Program: A Way Forward. Washington, DC: The National Academies Press, 2013, https://doi.org/10.17226/13511. 

9. Ben Masters, Wild Horses: The Consequences of Doing Nothing, National Geographic, February 7, 2017, Accessed August 7, 2020, https://www.nationalgeographic.com/adventure/featur es/environment/wild-horses-part-two/ 

10. Bait-Trapping Questions and Answers, U.S. Department of the Interior, Bureau of Land Management, Accessed August 7, 2020, https://www.blm.gov/sites/blm.gov/files/wildhorse_201 7AdobeTownGather_QAs.pdf 

11. Kate Schoenecker, Counting America’s Wild Horses and Burros: Better Estimates for Population Management, U.S. Geological Survey, Accessed August 7, 2020, https://www.usgs.gov/centers/fort/science/countingamerica-s-wild-horses-and-burros-better-estimatespopulation?qt-science_center_objects=0#qtscience_center_objects; Ben Masters, Can Fertility Control Keep Wild Horse Herds in Check?, National Geographic, February 8, 2017, Accessed August 7, 2020,  https://www.nationalgeographic.com/adventure/features/environment/wild-horses-part-three/; Theodore Roosevelt National Park, Fertility Control Produces Potential for Feral Horse Management in Park Units, National Park Service, Accessed May 5, 2021 https://www.nps.gov/articles/horse-fertility control.htm.

12. BLM Colorado Featured Partnership, Department of the Interior, Bureau of Land Management, Accessed August 7, 2020, https://www.blm.gov/programs/wild-horse-and burro/partnerships/little-bookscliff#:~:text=Just%20outside%20of%20Grand%20Junc tion,BLM%20in%20the%20early%201980s. 

13. Wild Horse and Burro Adoption Program Data, Bureau of Land management, Accessed October 20, 2020, https://www.blm.gov/programs/wild-horse-and burro/about-the-program/program-data 

14. Wild Horse and Burro Adoption Requirements, Bureau of Land Management, Wild Horse and Burro Program, Accessed August 7, 2020, https://www.blm.gov/sites/blm.gov/files/wildhorse_ad optionsandsales_generalreq_9.11.19.pdf 

15. About the Meeker Mustang Makeover, Meeker Mustang Makeover, Accessed August 7, 2020, https://meekermustangmakeover.org/about-the event/. For more information on the Meeker Mustang Makeover, see https://meekermustangmakeover.org/. 

16. Wild Horse Inmate Program (W.H.I.P), Colorado Correctional Industries, Accessed August 7, 2020, https://www.coloradoci.com/serviceproviders/whip/in dex.html?intro 

17. Mustang Heritage Foundation, Bureau of Land Management, Accessed August 7, 2020, https://www.blm.gov/programs/wild-horse-and burro/partnerships/mustang-heritage-foundation

18. Program Data, U.S. Department of the Interior, Bureau of Land Management, Accessed August 7, 2020, https://www.blm.gov/programs/wild-horse-and burro/about-the-program/program-data Congressional Research Service, Wild Horse and Burro Management: An Overview of Costs, October 14, 2020, Accessed May 5, 2021, https://www.everycrsreport.com/files/2020-10- 14_IF11060_cb752465d91df4573d759f1465428f7fa5a 952eb.pdf. 

19. Friends of the Mustang and Piceance Mustangs are 501(c) 3 non-profit, non-political organizations that work closely with the BLM on wild horse 

management. For more information on Friends of the Mustang, see http://www.friendsofthemustangs.org/. For more information on Piceance Mustangs, see https://piceancemustangs.org/. In addition, Wild Horse Warriors of the Sand Wash Basin is an emerging non profit. For more information, see https://wildhorsewarriorsforsandwashpasin.com/

Rangeland in northwestern Colorado near Sand Wash. While horse populations grow exponentially, grass production on rangeland changes year to year in response to precipitation, and is projected to decrease overall with climate change on western Colorado rangelands.

H. Doucette, Master of Arts Program, Department of History, Colorado State University 

L. Carr Childers, Associate Professor, Department of History, Colorado State University 

R. Bruegger, Regional Range Specialist for Western Colorado, CSU Extension.

Colorado State University, U.S. Department of Agriculture and Colorado counties cooperating. CSU Extension programs are available to all without discrimination. No endorsement of products mentioned is intended nor is criticism implied of products not mentioned.