I have a slight issue one of my ducks is not laying and possibly responsible for some soft shells I have seen around the yard. I don't know who it is but they are on layer feed and have oyster shell in a separate food bowl. All of my ducks are around 2-3 years old and there is one drake for 3 females. This whole season I have only gotten 2 eggs a day consistently. Is there anything I can do to help my ladies?