I don't sell my duck eggs and I only give mine to my friends and family at this point, but I will tell you that I don't have the heart to leave my duck eggs looking so poopy and muddy, so I take an old magic eraser- you know the ones for scrubbing the wall- and rinse out any cleaning agents in...
Well my little picket fence around my patio has worked after all, I guess they feel like it's a hassle to jump over-in and out of the patio so they've given up. My porch is now poop free :) yay!
You know I started searching the internet today with the same question and all of the situations and suggestions really resonate with what has happened to my small flock mentioned in this forum.. My ducks started inhabiting my concrete patio about a week ago and now that I think about it...