Neat little game with a good variety in levels. Hope the ducklings were not too dizzy :)
I especially liked the “BOING” sound effect and the gentle screen fade between levels. Nice touch!
I’d appreciate if there was an in-game way to tell how many levels were left. The simplest solution would be to just display a number after each level. Also, to reduce the waiting periods when hunting the last stray ducklings, you could make the level spin slightly faster for each duckling collected to give the level a nice flow.
But good job overall! Very charming :)