Aretas Saunders attended Yale University and Yale School of Forestry, graduating in 1907. He then joined the U.S. Forest Service, spending several years in the Lewis and Clark, Gallatin, and Deer Lodge National Forests in Montana. As a result, he published "Birds of Montana". In 1912 Aretas left the Forest Service and began his career as a teacher in New Haven, Connecticut, teaching general science, geometry, physics, and trigonometry. In 1914 he began teaching biology at Central High School in Bridgeport, Connecticut, where he taught until 1949. During World War I, Aretas became a Sergeant in the Home Guard. In 1921 he began summer work at the Roosevelt Wildlife Forest Experiment Station in the Allegany State Park and as a result published "Birds of Allegany State Park". During the summers of 1927 to 1940, he was instructor of ornithology at the Allegany School of Natural History. He retired in 1949. Saunders became an Associate of the American Ornithologists Union in 1906, a Member in 1920, and a Fellow in 1950. In 1954, he was a guest lecturer in ornithology at Cornell University. The National Audubon Society established an Aretas A. Saunders Memorial Fund in 1972.