Wild Bison Brucellosis Management and Livestock Conflict

Brucellosis in wild bison creates ongoing conflict between wildlife conservation and livestock industry interests, affecting bison welfare and management.

Key Facts

Brucellosis (Brucella abortus) infects approximately 50% of Yellowstone bison based on seropositivity testing
Transmission from bison to cattle has never been documented in free-ranging wild conditions, though transmission via elk has been documented
Fear of brucellosis transmission has been used to justify lethal removal of thousands of bison leaving Yellowstone
Bison-to-cattle transmission requires direct contact with aborted fetuses or birth materials
Vaccination programs using RB51 vaccine reduce brucellosis prevalence in bison but require capture
The bison population is managed to stay within politically determined limits despite adequate habitat outside Yellowstone
Most lethally removed bison are sent to slaughter, raising questions about the ethics of wildlife-livestock policy interactions

Welfare Considerations

Bison lethally removed at Yellowstone boundaries undergo capture, transport, and slaughter stress that represents a significant welfare burden. Calves may be separated from mothers during hazing operations. The conservation and welfare costs of brucellosis-motivated culling programs fall disproportionately on wild bison, while the actual disease transmission risk to cattle remains scientifically disputed.

What You Can Do

Support science-based bison management policies that challenge assumptions about brucellosis transmission risk
Advocate for expanded bison habitat on public lands that reduces boundary conflict
Donate to organizations working on bison conservation and brucellosis vaccination alternatives
Learn about the scientific evidence on bison-to-cattle brucellosis transmission
Follow ongoing advocacy for Yellowstone bison as a wildlife management case study