Many Issues Unresolved in Yellowstone Bison-Cattle Brucellosis Conflict
RCED-93-2: Published: Oct 21, 1992. Publicly Released: Nov 25, 1992.
Pursuant to a congressional request, GAO examined the controversy on the possible transmission of brucellosis from Yellowstone's free-roaming bison and elk herds to cattle grazing on lands outside the park boundary.
GAO found that: (1) the likelihood of transmission of brucellosis from bison and elk to cattle in the wild is not clear; (2) the most recent study of Yellowstone bison showed that brucellosis was found in about 12 percent of the bison killed in the area; (3) a study of 151 Yellowstone elk showed that the organism was found in none of them; (4) the National Park Service (NPS) and Montana wildlife officials are unaware of any documented cases of brucellosis transmission from wildlife, including bison and elk, to livestock in the wild; (5) the Montana State Veterinarian estimates that the cost of testing cattle exported from Montana for brucellosis would have been $438,000 in 1989; and (6) alternatives for managing the bison-cattle controversy include establishing bison management areas outside the park to provide winter range for bison, preventing bison from migrating from the park through various methods including shooting, and attempting to eradicate the brucellosis organism, which would require trapping and testing bison, as well as slaughtering, neutering, or temporarily sterilizing them.