At Smithsonian, Jimmy Stamp posted a brief history of bird automata. And yes, I know that Bubo from Clash of the Titans, above, isn't real. But... Bubo! Clash of the Titans! From Smithsonian:
The earliest example (of an avian automaton) dates to 350 B.C.E. when the mathematician Archytas of Tarentum, who some credit with inventing the science of mechanics, is said to have created a mechanical wooden dove capable of flapping its wings and flying up to 200 meters, powered by some sort of compressed air or internal steam engine. Archytas’ invention is often cited as the first robot, and, in light of recent technological advancements, perhaps we could even consider it to be the first drone; the very first machine capable of autonomous flight. Very few details are actually known about the ancient mechanical dove, but it seems likely that it was connected to a cable and flew with the help of a pulley and counterweight. This early wind-up bird was chronicled a few hundred years later in the pages of a scientific text by a mathematician, Hero of Alexandria."A Brief History of Robot Birds"