Adverse impacts to wild horses primarily result from management that reduces the forage, health, and free-roaming nature of wild horses. The expansion of the McCullough Peaks HMA under alternatives B and D, would result in beneficial impacts to wild horses by adjusting the HMA boundary to more accurately correspond to the range the resident herd uses, rather than continued attempts to recapture and move horses. Alternatives B and, to a lesser extent, Alternative D implement proactive management and constrain resource uses and disruptions (e.g., restrictions on organized special recreation permits [SRPs] in HMAs) in ways beneficial to wild horse forage and health. Alternatives A and C would result in similar impacts to wild horses, with the implementation of Alternative C causing more adverse impacts to wild horses than Alternative A, especially in the short term. Under all alternatives, wild horse populations may be brought into balance with available habitat and resources needed to sustain genetically viable herds.