In 1936, the Arizona Boy Scouts mounted a statewide campaign to save the bighorn sheep. The scouts first became interested in the sheep through the efforts of Major Frederick Russell Burnham. Burnham observed that fewer than 150 of these sheep still lived in the Arizona mountains. The National Wildlife Federation, the Izaak Walton League, and the National Audubon Society also joined the effort. On January 18, 1939, over of land were set aside to create the Kofa National Wildlife Refuge and the Cabeza Prieta National Wildlife Refuge.