Part I: What You Need to Know About Feral Horses in the U.S.

Written by Kylie Field and Claudia Ingham

In this two part series, author Kylie Field, assisted by Oregon State University Senior Instructor Claudia Ingham, walk us through the issues surrounding feral horse populations in the United States.

Part I

What do you know about wild horses in the U.S.? 

If you’ve ever hit the open road and travelled through any of the 10 western U.S. states, that wild horses and burros call home, you’ve probably caught a glimpse of these “spirits of the West” scattered along the landscape. Some of you may have friends who have adopted wild horses, or even have adopted one yourself.  You’ve likely heard some talk about wild horses but how much do you really know about these animals? As the landscape changes around them, what challenges do they face? What challenges do they cause?  How is their well-being? And why should you care? 

Before we get carried away, let’s get technical. Although America’s free-roaming horses are often referred to as “wild”, these horses are not native to the land. The last truly wild horses in North America went extinct over 10,000 years ago during the last “Ice Age” (BLM, 2020a). The domesticated horses that were introduced to the Americas by Europeans in the 15th and 16th centuries were genetically distinct from their wild ancestors that had previously lived here.  Many of these new horses escaped captivity and began to reproduce in the wild, creating the herds of “wild” horses we see today. Over time, the herds expanded to include lost American cavalry horses, horses belonging to Native Americans, as well as other unwanted or abandoned horses (Global Rangelands, 2021; BLM, 2020a).  Because they are the descendents of domesticated horses, we can more accurately refer to them as “feral” horses, and not as wild.  

Terminology is an important consideration because, while we may like to think of them as free-living creatures, the presence of these horses is ultimately the product of human migration and should change how we perceive and manage them. Regardless of what they are called, the free-roaming horses in our country are subjected to, and dependent on, the care and management of humans in the United States. 

Feral horse populations are growing exponentially. If we continue to manage feral horses the way our government has since 1971, the horses and the land they inhabit are in trouble. If we are to claim any right to keep these beloved horses on our soil, the people of the United States must anticipate how our management practices will affect their survival and well-being.  

Do you know what laws protect America’s feral horses? 

The relationship between horses and humans is undeniably special. Perhaps it’s the invaluable services they provide, like transportation, labor, sport, and companionship, which cause us to treat them differently than other livestock. Their grace, beauty and athleticism draw our affection. Most Americans today would never fathom causing these creatures any harm, but it wasn’t always this way.  

The first threats to America’s feral horses began as settlers in the mid-1800s began claiming territories across the rangelands. Habitats for the feral horses and other grazers, such as bison, decreased in size (Global Rangelands, 2021). The large number of expendable, free-roaming horses in the West began to draw the attention of impoverished Americans. During the economic recessions surrounding the American Civil War, World War I and World War II, horse meat was a necessity for many who would have otherwise starved. Even though most Americans stopped eating horse meat after World War II, the pet food market and the demand for horse meat in other countries caused “mustangers” to continue rounding up feral horses to sell for slaughter.  In the 1950’s, the history of feral horses began to change (Forrest, 2017; BLM, 2020a).  

After witnessing the inhumane way wild horses and burros were gathered by “mustangers” for slaughter, a Nevada native Velma B. Johnson, or “Wild Horse Annie” as she was later known, led a campaign to end their exploitation. Her cause drew the support of many Americans, shifting the general attitude towards the feral horses.  

In response to the growing public concern over the well-being of the horses, the Wild Free-Roaming Horses and Burros Act (WFRHBA) was signed by President Nixon in 1971. The law protects wild horses and burros on public lands from “capture, branding, harassment, or death” (Public Law 92-195). Additionally, under the WFRHBA, the Bureau of Land Management and the United States Forest Service are tasked with ensuring the health of the wild horses and the public land they reside on.  The Bureau of Land Management (BLM) is responsible for most of the public land where feral horses reside and is considered the primary government agency involved in the management of these horses.  

How many horses is too many horses? 

Due to their protection and lack of natural predators (Scully et al., 2015) the population of feral horses on federal land has rapidly increased past manageable levels. The BLM oversees maintaining  “appropriate management levels” (AML) of free-roaming horses to ensure their population density does not exceed the grazing capacity of the land which they live on, preventing damage to the landscape and depletion of resources for other species (BLM, 2020). There are an estimated 95,114 feral horses and burros on U.S. rangelands, far exceeding the Bureau of Land Management’s AML of 26,715 (BLM, 2020a).   

 Due to the laws and demands of stakeholders, BLM has been required to attempt reducing the number of feral horses by controlling their fertility via contraceptive methods, sterilization, and live removals to new areas or holding pens for adoption (BLM, 2020a). The number of feral horses populating the rangelands of the West has created significant ecological, social and economic problems for the country, and poses a risk to the well-being of the horses themselves.  

Why can’t we all agree on how to manage these animals? 

There has been much concern from stakeholders such as animal rights activists, feral horse advocacy groups and the public regarding the wellbeing of feral horses under the management of BLM (Lawton, 2017). When slaughter and surgical sterilization were considered by BLM for large scale population control, public backlash came in the form of petitions, letters and lawsuits (Morell, 2016; TVP, 2019). Most of the public supports the use of reversible fertility control and adoption for population management because these methods are seen as being more humane than permanent methods such as sterilization or euthanasia (Morell, 2016). Still, certain animal rights groups oppose any contraception use and believe that it is in the best interest for the welfare of the horses to live freely without human intervention (HSUS, 2020).  

Stakeholders in favor of more immediate and permanent methods for population reduction include many BLM employees, ranchers, hunters, and ecologists concerned with the health of the soil and vegetation in areas populated by horses. The massive horse population deteriorates the land and causes resource scarcity not only for the horses themselves, but for other animals such as grazing cattle and wild game as well (Lange, 2017; Munoz et al., 2020). Most herd areas are in semi-arid climates (think sagebrush steppe ecosystems of the Wild West). These landscapes are particularly sensitive to disturbance by large herbivores that roam here. It’s been shown that grazing animals alter the vegetation in these regions mainly through 1) soil compaction, 2) selective plant consumption, and 3) trampling and rubbing. When grazing is uncontrolled, these actions result in diminished foliar cover, shrub size and species diversity (Beever et al., 2008). Frustration for many stakeholders arises from the fact that the timing, duration and intensity of grazing by livestock is heavily regulated on public land, and wild ungulate (deer, antelope, elk, etc.) populations are maintained at appropriate sizes by hunters. Feral horses, who share the same land, water sources, and diet as the wild game and livestock, aren’t controlled in the same way (Masters, 2017). Pressure from stakeholders, as well as from BLM’s obligation to protect the species and the landscape, cause a real need for a practical solution for humane population control.  

What are we doing about the feral horse problem? 

In Part 2 of this article, we will walk you through the methods that BLM has implemented for the population control of feral horses, including live removals, adoptions, and contraceptive methods. You’ll see what is working, what is not, and what still needs to be done for these free-roaming horses of the West.  

Read part II of this article, here.


Kylie Field graduated from Oregon State University in 2021 with a Bachelor of Science degree in Animal Science. She plans to attend veterinary school and continue studying equine science. In her free time, Kylie enjoys riding horses and spending time with her pets at home.  
Claudia S. Ingham, PhD is a Senior Instructor in the Department of Animal and Rangeland Sciences at Oregon State University where she teaches ethics related to domestic animal use and rangeland ecology including the management of grazed landscapes.  Her research on targeted grazing to manage Himalaya blackberry and English ivy with goats is published in Invasive Plant Science and Management.

Claudia holds lifetime certification with the American Riding Instructors Association (ARIA) in the disciplines of Recreational Riding, Eventing and Dressage and teaches clients near her home in Marion County, Oregon. For riding and pasture consulting questions, she can be reached at: Eco.Ag.Consultation@gmail.com
Literature Cited in This Article (Parts I & II)
Provided by Kylie Field

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