His position as a 24-year old zoology student in comparison to the others was remarkable and Jurgen Haffer notes that this work acted as a springboard for his future career. Stresemann had eminent peers and mentors in Ernst Hartert, Carl Zimmer, Otto Kleinschmidt and Carl Eduard Hellmayr. The "Aves" work continued to be updated until 1934 and Stresemann produced one of the most comprehensive treatises on birds. It covered anatomy, morphology, behaviour, physiology, and evolution in ways that no other work had done before. It was not until the 1960s that anything comparable was produced in the English language in the multi-author work edited by A.J. Marshall (1960-1961) and later in the multi-volume series on "Avian Biology" edited by Farner and King. In 1920 he succeeded the Anton Reichenow (in his seventies) as curator of ornithology at the Zoological Museum in Berlin, a position he stayed in until his retirement in 1961. The surprise appointment was through Kükenthal's influence. He attended meetings of the Deutsche Ornithologen-Gesellschaft where he was known for his argumentation. He proved himself as a person of wide reading and immense knowledge. His first student was Bernard Rensch. This was followed by Theodor Elsässer who studied iridescent feathers for his doctorate. This was followed by Ernst Mayr on zoogeography, Ernst Schüz on the evolution of powder down, Wilhelm Meise on systematics, Emil Kattinger and Fritz Frank. They pursued diverse topics in ornithology. He was made professor in 1930 and from 1946 to 1961 he was tenured professor at the Humboldt University of Berlin. In November 1935, Stresemann was invited to Yale University by Leonard Cutler Sanford and was offered a position there. Stresemann however felt that he belonged to Berlin. He wrote that he could have worked there but could not live there. During the war years from 1941, he ensured that the 40,000 bird skins and rare books were safely stored in an underground locker. They were safely restored after the war. He also kept up communication with European ornithologists who became German prisoners of war such as David Bannerman. He ensured that they obtained the latest research papers as well. During his career, he worked continuously on several areas of ornithology and maintained a broad interest that allowed him to produce a major treatise on the history and development of the field of ornithology.