In American Wild Horse Campaign v. Raby, the Tenth Circuit Court of Appeals reviewed a Bureau of Land Management (BLM) plan aimed at managing wild horse populations in southern Wyoming. The BLM’s plan included reducing certain horse populations to zero, a measure challenged by the plaintiffs. The court found the plan to be arbitrary and capricious because it failed to adequately address the ecological balance implications of such drastic population reductions.

As a result, the Tenth Circuit reversed the BLM’s decision and remanded the case, requiring the agency to provide a more thorough analysis of how its management strategy would impact the ecosystem. This ruling emphasizes the necessity for federal agencies to consider ecological factors comprehensively when making wildlife management decisions.