In 1872 or 1873, Yount was hired as a seasonal guide, wrangler and packer for geological survey expeditions with the aim of mapping broad swaths of the Rocky Mountains. The Hayden Survey, led by Ferdinand Vandeveer Hayden and funded by the Department of the Interior, was one of several regional survey projects that were combined to form the United States Geological Survey in 1879. Hayden had been one of the leading advocates for the creation of Yellowstone National Park, which President Ulysses S. Grant signed into law on March 1, 1872.