American bison were reduced from 60 million to fewer than 1,000 individuals by the 1880s through mass slaughter. Their recovery is a conservation success, but individual welfare challenges remain from disease management, habitat restriction, and human-wildlife conflict.
Wild bison welfare is affected by the management consequences of their recovery. Bison that leave protected Yellowstone boundaries face capture, disease testing, and sometimes slaughter - acute welfare events driven by livestock industry concerns about brucellosis. The capture and handling of large, naturally fearful animals causes significant stress. Bison remaining in Yellowstone experience a naturally regulated population with winter mortality from starvation and cold - natural but representing individual suffering at scale. Bison in commercial herds face conditions ranging from extensive ranching with adequate space to semi-intensive operations that restrict natural grazing and social behavior. The conservation success of bison recovery masks ongoing welfare challenges in how recovered populations are managed.