Interesting game! Is the bird just a regular critter? It doesn't seem to react to the music. The achievements are a great addition, but I couldn't find any clues about how to unlock more of them. Good work overall!
The bird reacts if you have two or more items attached to environmental objects playing automatically, at which point they will start to sing along.
Oh, I din't know I could do that :D
Yup! Every item you can pick up can be attached to Windy Trees, Drippy Branches, or Bubbling Brooks to make its own musical loop!
I really wish I'd had time to add a tutorial!