The findings, compiled by the U.S. Geological Survey and published in the Public Library of Science, found that areas north of Dubois, Wy. and northwest of Cody, Wy. were hot spots for brucellosis infection among large elk herds, with between 10 percent and 30 percent of the herd infected. The study analyzed blood samples from over 6,000 elk between 1991 and 2009.
The prevalence of brucellosis in elk with limited or no exposure to Yellowstone-region bison isn’t a surprise to bison advocates, who have long argued that elk are the most likely carriers of the disease to regional cattle. These herds had virtually no exposure to the 23 feeding areas frequented by both elk and bison.
No word on how any brucellosis management plans would be affected by this new piece of scientific knowledge. On the one hand, it does weaken the claim by state officials and local cattlemen that Yellowstone bison are the most likely carried of the disease, which can cause pregnant cows to abort their fetuses. (It’s also known by the name of Bang’s disease.) But it does intensely complicate attempts to lessen the impact of the disease in the region; brucellosis rates are on the rise and Montana has lost its designation as a brucellosis-free zone. If it can be determine that elk are the major carriers, a major crisis is on the horizon: there are over 100,000 elk in the Greater Yellowstone Ecosystem, and managing them is a lot more complicated than just culling some bison when they wander off the farm. This is a major finding; we wait to see whether any management changes ensue.
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