Bison were reduced from 60 million to fewer than 1,000 by the late 19th century. Their recovery is a conservation success, but management interventions for expanding herds create important individual welfare considerations.
Wild bison welfare is shaped primarily by management decisions at the landscape scale. Brucellosis control — which requires separating bison from cattle to prevent disease transmission — drives some of the most welfare-significant interventions, including hazing by helicopter and snowmobile, culling at park boundaries, and live capture for slaughter. These interventions cause acute stress and family group disruption in a socially complex species. Bison herds that can range freely across large landscapes, self-regulate seasonal movement, and engage in natural social behaviour including the rut show positive welfare indicators absent in managed herds with restricted movement. Private conservation ranches that manage pure bison as wildlife rather than livestock, with minimal intervention, produce the most welfare-positive outcomes alongside conservation value. Translocation programs to restore bison to tribal lands also create welfare considerations around capture, transport, and adaptation to new landscapes.