Quite fun, it felt pretty nice to control. I got 50 leaves before I tested dying :)
I thought it was interesting that the bubble hitbox was so much larger than the ant hitbox, making it easy to lose the bubble on accident. It would have been nice for the bubble to flash or something to warn that it was about to expire.
I liked the way it controlled, perhaps it would have been fun to add some momentum to the player character to add risk when you commit for a leaf. I also would have been interested in the difficulty ramping up the longer you play (faster birds, more hazards, etc). Basically looking for something to force you into collecting risky leaves.
Overall an enjoyable time, nice job!