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Washington Office Division of Public Affairs
Release Date: 10/07/11
Contacts: Tom Gorey , 202-912-7420  

BLM Announces Fall-Winter Wild Horse and Burro Gather Schedule

The Bureau of Land Management today announced its tentative fall-winter schedule for gathering wild horses and burros from overpopulated herds on Western public rangelands. The gathers are needed to bring herd sizes into balance with other rangeland resources and uses, as required by Federal law and approved land-use plans. Along with removals, the fall-winter gathers will be used to apply a fertility- control vaccine during the ideal time (from November through February) for maximum efficacy.

In the new fiscal year (2012), which began October 1, the BLM plans to apply several population growth-suppression techniques to approximately 2,000 wild horses. Methods to be analyzed in gather-related environmental assessments will include applying the fertility-control vaccine porcine zona pellucida (PZP); adjusting sex ratios in some herds to favor males; and incorporating geldings as components of breeding herds. All of these measures are aimed at reducing the number of on-the-range pregnancies.

The public and media are invited to observe the gathers. Observation points will be determined by the BLM in a manner that recognizes the need for good viewing sites, along with the need to ensure viewer and animal safety.

All helicopter-driven wild horse gathers will be completed by Feb. 28. The tentative dates of the fall-winter gathers can be accessed at

The BLM estimates that approximately 38,500 wild horses and burros (about 33,000 horses and 5,500 burros) are roaming on BLM-managed rangelands in 10 Western states based on the latest data available, compiled as of February 28, 2011. Wild horses and burros have virtually no natural predators and their herd sizes can double about every four years. As a result, the agency must remove thousands of animals from the range each year to protect rangeland resources, such as wildlife habitat, from the impacts of overpopulation. The 1971 Wild Free-Roaming Horses and Burros Act mandates that once the Interior Secretary “determines...that an overpopulation exists on a given area of the public lands…he shall immediately remove excess animals from the range so as to achieve appropriate management levels.” 

The BLM manages more than 245 million acres of public land, the most of any Federal agency. This land, known as the National System of Public Lands, is primarily located in 12 Western states, including Alaska. The BLM also administers 700 million acres of sub-surface mineral estate throughout the nation. The BLM's mission is to sustain the health, diversity, and productivity of America’s public lands for the use and enjoyment of present and future generations. In Fiscal Year 2015, the BLM generated $4.1 billion in receipts from activities occurring on public lands.

Last updated: 10-07-2011