Okay. So I just checked them again at bath time. And while I was toweling them off one by one, I note that three of my 12 Rouen ducklings that are all out of one pair of ducks have feathering on the legs. One has about 5 cream-colored feathers starting on the right ankle, but only about 3 feathers on the left. The other two only have one or two cream-colored feathers on each ankle. But you gotta look pretty hard to find any of them, and if their feet weren't black, I doubt anyone would notice them. Strange.