18.1 cubic feet, 2 audio tapes, 27 audio cassettes
The papers of a wildlife field biologist for the Missouri Department of Conservation. They include correspondence, field diaries, maps, reports, studies, publications, and photographs. Christisen specialized in the study of native prairie ecosystems, prairie chickens, squirrels, and mast (forage nuts). The papers also include railroad time tables, accident reports, photographs, worker's logs, publications, maps, and blueprints documenting his interest in railroads.