I have 4 Khaki Campbell females who have all been laying for a while. I get anywhere from 1-4 eggs a day. Yesterday I got none. Looked all over the coop, around the yard, nothing! This morning I went out to let them out and there were 8 eggs in the coop. Is this normal, something that can happen from time to time? It's our first year for ducks and I love them, and am always amazed!!!!