Horses have limited binocular (forward-facing) vision and rely on head movement and reduced speed to accurately judge depth and terrain.

During helicopter gathers, wild horses are driven at sustained speeds across unfamiliar landscapes and are unable to stop, lower their heads, or visually reassess obstacles.

Under these conditions, reduced depth assessment increases the risk of misjudging terrain features such as washes, drop-offs, fencing, and trap wings, which can result in falls, collisions, and musculoskeletal injuries.