Not bad as a concept, but a far cry from a a game. no difficulty increase, way to easy. The music loop becomes annoying very fast. I stopped because I got bored.
So you have a concept, not very original, but ok. now develop it. You can also improve the boundaries (sometimes although you fall right in the middle of the tree you still land in the ground. Sometimes you fall almost outside but you don't fail...
Add more birds, other obstacles in the trees, trees further apart, some kind of boss that appears behind you and tries to catch you, I don't know. There is a ton of possibilities.