The million-acre Cibola-Trigo HMA extends from the Imperial Dam, west of the Colorado River, to Walters Camp in California’s lower Sonora Desert. After the BLM rounds up and removes 350 burros from Cibola Trigo, it will move across the Colorado River into California’s Chocolate-Mule HA. There the agency will target so called “nuisance burros” who reside on private land that was once a part of the HA, for removal.