Well, I know this is an old thread, but we have ducks for the first time ever (13 years) and THEY ARE NASTY - poop all on the bottom of the pool. I was just checking to see what everyone else did. I saw some floaty crocodile heads (blow-up) that supposedly will scare them off and just read tonight about floating snakes (blow-up). Guess I'll go get both and try them. We also, for the first time ever, have Mourning Doves in our garage! We've accommodated them this time, but a fake owl is going on that shelf as soon as those two babies fly out! I tore the nest down before they even finished it, but the next morning, the garage door wasn't even all the way up when they rushed under, the mama parked her little feathered... and she never moved again for a month. We have grand-birdies!!