Born in Kalispell, Montana, Bird developed a love for the art of animation at an early age and was mentored by Milt Kahl, one of Disney's reputed Nine Old Men. He was part of one of the earliest graduating classes of the California Institute of the Arts with John Lasseter and Tim Burton. Afterwards, Bird begin his career as an animator for Disney in the films "The Fox and the Hound" and "The Black Cauldron" and wrote the screenplay for "Batteries Not Included". He also served as a creative consultant on "The Simpsons" during its first eight seasons, where he helped develop the show's animation style.