Contact: Tom Gorey, BLM Public Affairs (202-912-7420)
Updated as of July 7, 2015
The BLM manages, protects, and controls wild horses and burros under the authority of the 1971 Wild Free-Roaming Horses and Burros Act (as amended by Congress in 1976, 1978, 1996, and 2004). This law authorizes the BLM to remove excess wild horses and burros from the range to sustain the health and productivity of the public lands. The BLM also manages the nation’s public lands for multiple uses, in accordance with the 1976 Federal Land Policy and Management Act. The Bureau manages wild horses and burros as part of this multiple-use mandate.
Below are key statistics related to the Wild Horse and Burro Program. More complete information, including historical figures, can be found on our data page. In addition, more information on how the BLM obtains wild horse and burro population estimates can be found on our Rangeland and Herd Management and Science and Research pages.
Wild Horse and Burro Population Estimates
As of March 1, 2014
As required under the Wild Free-Roaming Horses and Burros Act of 1971, the BLM conducts an annual population inventory to estimate the number of wild horses and burros roaming on Western public rangelands. The Appropriate Management Level (AML) is the number of wild horse and burros that BLM has determined can exist in balance with other public land resources and uses. Click here to learn more about how the BLM estimates wild horse and burro populations.
Population Growth-Suppression Treatments
In a June 2013 report, the National Academy of Sciences (NAS) found that no highly effective, easily delivered, and affordable fertility-control methods were currently available to manage wild horse and burro population growth; the NAS also urged the BLM to use research better tools. The currently available fertility control vaccine, known as porcine zona pellucida (PZP), is limited in the duration of its effectiveness – up to 22 months for a formulation that must be hand-injected into a wild horse. A second formulation of PZP can be deployed via ground-darting, but is effective for only up to one year. This formulation is not a viable fertility-control option for most wild horse herds because of the animals’ propensity to avoid human contact, along with the vast size of their ranges, which make it difficult to locate and track individual horses. Learn more here about BLM's fertility control efforts for wild horses and burros.
Video Clip: Below is a two-minute video from June 2012 of the BLM's second annual tour of a pasture holding facility in El Dorado, Kansas. To view a larger version of this video, select this link.
Wild Horse and Burro Acreage
In 1971, when Congress passed the Wild Free-Roaming Horses and Burros Act, these animals were found roaming across 53.8 million acres of public land, known as Herd Areas, of which 42.4 million acres were under the BLM’s jurisdiction. Today, the BLM manages wild horses in subsets of these Herd Areas, known as Herd Management Areas (HMAs). Under the 1971 Act, horses and burros may not be re-located to other public lands where they were not found roaming when the law was passed.
Total Number of Herd Management Areas
Total Acreage of Herd Management Areas
31.6 million acres
Herd Management Area Acreage Managed by BLM
26.9 million acres
Wild Horse and Burro Population in BLM's Off-Range Corrals and Pastures
All wild horses and burros in holding, like those roaming Western public rangelands, are protected by the BLM under the 1971 Wild Free-Roaming Horses and Burros Act, as amended. The BLM maintains a monthly facilities report, which can be found by clicking on the desired fiscal year: FY-2015, FY-2014,FY-2013, FY-2012, FY-2011. The total capacity of all BLM off-range holding facilities is 50,929 animals.
(As of June 2015)
Total Off-Range Population
Wild Horse and Burro Removals
Wild horses and burros have virtually no natural predators and their herd sizes can double about every four years. As a result, the BLM removes thousands of animals from the range each year as part of its efforts to control herd sizes.
About 8,400 wild horses and burros immediately became eligible for sale under the December 2004 sale-authority law (the so-called "Burns Amendment"), which directs the BLM to sell "without limitation" to any willing buyers animals that are either more than 10 years old or have been passed over for adoption at least three times. Since 2005, the BLM has sold more than 5,500 horses and burros. It has been and remains the policy of the BLM, despite the unrestricted sales authority of the Burns Amendment, not to sell or send any wild horses or burros to slaughterhouses or to "kill buyers."