Murie had been hired by the US Biological Survey as a wildlife biologist and spent much of the early 1920s studying Alaskan caribou, including their movements and populations. His work took him into the Brooks Range and Mount McKinley National Park, now Denali National Park and Preserve, where wildlife research was still in its early stages. The National Park Service describes his arrival in 1922 as the beginning of more intensive scientific research into the park's wildlife. He hoped to capture young bull caribou as part of an effort involving the possible interbreeding of wild caribou with domestic reindeer. Predator control was therefore considered a possible solution.In 1939, the National Park Service asked Adolph Murie to investigate the relationship between wolves and Dall sheep.