We incubated 41 eggs from our Black Swedish ducks, the only ducks we have on the farm. All our ducks were purchased from a hatchery last year. The eggs are currently starting to hatch and one of the ducklings is solid yellow. It is not a problem, however, we are wondering how we got a yellow duckling when I thought genetically Black Swedish were only supposed to have black ducklings. I guess the obvious answer is that our ducks are not "pure" Black Swedish ducks, but I was wondering if anyone had any thoughts.