The correct answer: Teton herd in Grand Teton National Park
A 2018 survey by the National Park Service found 131 sheep living within Yellowstone National Park. The population has been increasing steadily, even as they face more competition from the growing wolf population. In Jackson, there are two herds of sheep: one in Muller Butte in the National Elk Refuge, and the Teton herd in Grand Teton National Park. The Teton herd is small and genetically unique, and unlike the Yellowstone population has dropped in numbers by 50% in the last 10 years, making them extremely vulnerable to local extinction.