MILFORD, UT - MAY 31: Domestic livestock get water from private watering tanks on state land, outside federal disengaged horse management areas on May 31, 2017 outside Milford, Utah. The BLM, state officials and ranchers all over the Western United States are struggling with what to do about and how to control the burgeoning horse population in the west.  (Photo by George Frey/Getty Images)