I like the graphics. I agree with the other comments that the game is too luck-based, and thus the player's action becomes inconsequential to the outcome. Maybe you could add a lightning graphic just in the cloud, that is constantly moving horizontally in a certain pattern, and it will only strike down at random timing. (Like in the real life, the lightning appears inside the cloud too; only once in a while it strikes down.) This way, the player can see the pattern and try to choose different birds that's far away from the potential lightning strike. If you feel that's too easy, then may be try two lightnings moving independently at different speed and changing direction at random time; and there are clouds (could be moving randomly) in front of the lightning and thus the lightning may be obscured by these clouds sometimes. The movement of the potential lightning will give the player some kind of pattern to anticipate and the clouds in front could momentarily take away the player's ability to anticipate, but at least the player can make their action accordingly. Hope this makes sense.