The concept is simple and interesting, but while the game does work, it's is not in a state to be released. Going outside the playing field locks you out, and that alone disqualifies it, but hit detection is also more than a little unclear unclear, wich is a deal breaker for a game like this, the graphics are temporary at best and controlls aren't immediately obvious even with the tile slpash screen out right stating them. All of this needs fixing.
After fixing the immediate issues here are a few other pointers: the horizontal speed is quite low for maneuvering, two levels is very little, and the fact the only geometry they appear as is straight line along the bottom of the screen makes the game pretty dull. The ducks spawning randomly is workable, but I'd preffer if they were progresively getting lower, and with a bit more of a an area they can't appear in - both at the top and bottom.

i appreciate the calm music and the very clear hit detection. obviously unfinished and unpolished but it works!