Modification of the Sexual Cycle in Trout by Control of Light

Abstract

THE work of Rowan (1926, 1930), Bissonnette (1930, 1932, 1935) and others on the manipulation and control of sexual cycle in birds by the use of light is well known. Bissonnette (1935a, 1935b) further extended his work to include mammals, and Bissonnette and Csech (1936a, 1936b) used night-lighting in a practical manner to procure eggs from game birds during the winter. As far as known, fish have not received any similar attention experimentally, but as early as 1926 Rowan, from his work on birds, pointed out that the migrations of anadromous fishes might be influenced by the length of day. Hoover (1937) in a preliminary note of which this paper is a full discussion reported some light effects on trout.