I would certainly get them off my property one way or the other. Ducks are nasty creatures as are pigeons and I don't want either of them pooping on my yard or my house.
We had a house on Galveston Bay and the pigeons were roosting on our roof and nesting in our boat shed and it was horrible. I finally got them to move to someone elses house by squirting them with the hose as much as I could. There were some domestic ducks that wandered around but they didn't impact us.
It’s sad, birds are dirty, altho I enjoy them. I have discovered that lizards are also dirty (living down here in S. FL). My golden is hell on them, she is obsessed with them. Fortunately for the lizards she is rarely outside long enough to catch them. I love to take their photos, but most of the ones we have are not native anyway.