The field notes, correspondence, and photographs documents Helmut Buechner's observations of bighorn sheep in Arizona for the Bighorn Sheep Project, 1955 - 1956. There is a hand written notebook that lists plants collected (date, specimen number, type, sometimes numbered plot and abundance), photographs of bighorn sheep on geological formations (sometimes with captions including location and date). There are typed field notes for April 3 - July 4, 1955, detailing observations of flora and fauna (sometimes notes on abundance) with time of day, colleagues with whom worked, work completed, and travel routes, as well as lists of birds and plants seen. There is also a table summarizing bighorn count on Kofa Game Range, 1955, and excerpt of report on Cabeza Prieta Game Range. Locations include Yuma and other sites in Arizona.