Herd Management Areas
In 1971, Congress passed legislation to protect, manage, and control wild horses and burros on the public lands. The Wild Free-Roaming Horse and Burro Act declared these animals to be "living symbols of the historic and pioneer spirit of the West."
Congress further declared that "wild free-roaming horses and burros shall be protected from capture, branding, harassment, or death..." and that they are "...an integral part of the natural system of the public lands." Furthermore, Bureau regulation requires that wild horses and burros be considered comparable with other resource values within the area.
The Bureau of Land Management maintains and manages wild horses or burros in herd management areas (HMAs). In the ten states where BLM manages horses, there are 270 HMAs. In Wyoming, about 3,000 horses are managed within 16 different HMAs scattered across the state. Wyoming has no wild burros.
The Bureau establishes an appropriate management level (AML) for each HMA. The AML is the population objective for the HMA that will ensure a thriving ecological balance among all the users and resources of the HMA, for example, wildlife, livestock, wild horses, vegetation, water, and soil.