The Cooper Ornithological Society (COS), formerly the Cooper Ornithological Club, was founded in 1893 in California. Its name commemorates James Graham Cooper, an early California biologist. It publishes the ornithological journal The Condor and the monograph series Studies in Avian Biology (formerly Pacific Coast Avifauna). It makes the annual Loye and Alden Miller Research Award, which is given for lifetime achievement in ornithological research. It is a member of the Ornithological Council.