William Rowan FRSC (1891–1957), was a Canadian biologist and ornithologist best known as a founder of photobiology for establishing the link between the length of daylight and bird migration. Rowan was recognized for his findings with the Flavelle Medal in 1946. In 1993, Marianne Gosztonyi Ainley wrote Restless Energy: A Biography of William Rowan, 1891–1957 detailing his life.