Bureau of Land Management:
Wild Horse and Burro Herd Area
“This data set represents the spatial extent and boundaries for BLM Wild Horse and Burro Herd Area polygons. BLM Wild Horse and Burro Herd Areas have been designated by The Wild Free-Roaming Horse and Burro Act of 1971 as areas that wild horses and burros appeared to be inhabiting. Federal lands identified in 1971 but not managed for wild horses and burros are called Herd Areas.”