(b. Millersburg, Indiana, 5 May 1871; d. Madison, Wisconsin, 29 March 1944)
Juday, the son of Elizabeth Heltzel and Baltzer Juday, received the B.A. from the University of Indiana in 1896. He took the M.A. (1897) under Carl Eigenmann, who aroused his interest in aquatic biology. Having taught high school for two years, Juday returned to science to accept a position as biologist with the Wisconsin Geological and Natural History Survey. His work was interrupted by an attack of tuberculosis, but he returned to the survey in 1905 and remained there until 1930. At the same time, he assumed academic positions at the University of California (1904), the University of Colorado (1905), and finally the University of Wisconsin, where he collaborated with E. A. Birge in researches on Wisconsin lakes. (Their major monograph, “The Inland Lakes of Wisconsin. The Dissolved Gases,” was published in 1911.)
From October 1907 to June 1908, Juday traveled in England and on the Continent, visiting universities, biological stations, and lakes and meeting leading European aquatic biologists. On his return to the United States he began giving the courses on limnology and plankton organisms that he was to continue until his retirement from teaching in 1941. In February of 1910 he traveled in Central America, studying four semitropical lakes in Guatemala and El Salvador. In the same year Juday made studies on the Finger Lakes of New York.
From 1925 until 1941 Juday was director of the limnological laboratory at Trout Lake, Wisconsin, spending two months of each summer there. The station attracted biologists from the United States and Europe, and work done there was the subject of many important monographs. In his duties at the University of Wisconsin, Juday similarly encouraged research relations among departments whose work touched on lake studies. He was made professor of limnology, within the department of zoology, in 1931.
Juday published more than one hundred papers, including works on plankton, hydrography and morphometry of the inland lakes of Wisconsin, crustaceans, anaerobiosis, productivity of lakes, mineral content of waters and muds, hydrogen ion concentration, the effects of fertilizing lakes, and the growth of game fish and photosynthesis as indexes of the productivity of lakes. In addition to his teaching and research he worked with the Wisconsin Conservation Department, for whom he directed studies of the game fish of that state, and served as a consultant to the U.S. Bureau of Fisheries.
Juday was elected president of the Limnological Society of America upon its foundation in 1935; secretary and president of the Wisconsin Academy of Sciences, Arts and Letters; and president of both the American Microscopical Society and the Ecological Society of America. He received an honorary doctorate from the University of Indiana (1933) and the Leidy Medal of the Academy of Natural Sciences of Phildelphia (1943). He married Magdalen Evans on 6 September 1910; they had three children.
Upon his retirement from teaching, Juday was retained by the University of Wisconsin as a research associate. He died three years later, without completing the comprehensive treatment of Wisconsin limnology that he had begun.
I. Original Works. A complete list of Juday’s writings is Arthur D. Hasler, “Publications of Chancey Juday,”in Special Publications. Limnological Society of America, no. 16 (1945), pp. 4-9. Among the most important of these are three book-length reports, “The Inland Lakes of Wisconsin. I. The Dissolved Gases and Their Biological Significance,” in Bulletin of the Wisconsin Geological and Natural History Survey, sci. ser. 7, no. 22 (1911), written with E. A. Birge; “The Inland Lakes of Wisconsin. II. The Hydrography and Morphometry of the Lakes,” ibid., no. 27 (1914); and “The Inland Lakes of Wisconsin. The Plankton. I. Its Quantity and Chemical Composition,” ibed., sci. ser. 13, no. 64 (1922), written with E. A. Birge.
II. Secondary Literature. On Juday and his work, see Lowell E. Noland, “Chancey Juday,” in Special Publications. Limnological Society of America no. 16 (1945), pp. 1-3 .
Lowell E. Noland