This sound effect can be found on The Premiere Edition Volume 1, which was made by The Hollywood Edge. It shouldn't be confused with the similar-sounding sound effect, BIRDS, VARIOUS - LIGHT CHIRPING, ANIMAL which is available on the Hanna-Barbera Sound Effects Library.
Sound Effect Description
Bird, Meadowlark; Happy Chirps, Close Perspective.
Clean, Full Length and Unedited Link to the Sound Effect