Black Appleyard Ducklings

[Onthefarm]

Last fall we purchased some Silver Appleyard Ducklings. We raised them and now have started hatching their eggs. Our first hatch had some black ducklings in the mix. No markings with black feet and dark bills. We ONLY have Silver Appleyard ducks on our farm and there is no way any other duck got with ours. I've read a lot about dark phase and light phase and such. Need to hear from some more experienced breeders of Silver Appleyards.