Robert Sterling Ridgely (born 14 January 1946) is an American ornithologist, specializing in the neotropics. He is the co-author of three books on neotropical ornithology: the field guide The Birds of Panama (with John Gwynne), The Birds of Ecuador (with Paul Greenfield), and The Birds of South America (with Guy Tudor), of which two monumental volumes (out of four), covering the passerines, have appeared. He was long affiliated with the Academy of Natural Sciences in Philadelphia, then  Vice-President at the American Bird Conservancy until 2006.
Robert Sterling Ridgely is an American ornithologist specializing in neotropical birds. He co-authored three books on neotropical ornithology: The Birds of Panama (with John Gwynne), The Birds of Ecuador (with Paul Greenfield), and The Birds of South America (with Guy Tudor). Two volumes from four total have been published, focusing on passerines. Prior to his role at the American Bird Conservancy as Vice-President until 2006, he was affiliated with the Academy of Natural Sciences in Philadelphia.