Relaxing game,
it takes a couple of tries to understand what's going on, but once you do is quite fun.
I'd add some UI to say how far we went + how high we went, maybe with some leaderboard system including maybe the number of other birds you found along the way. This would add some replayability to the game. I also think the collider/trigger to "collect" other birds is a bit too small, maybe make it a bit larger or make other birds in the flock also able to trigger the "collection"
The art looks nice and the music fits well. Good job!