Well hopefully if you can't neither can a predator because we just had a poster lose one of their ducks and eggs to a skunk because she was brooding outside. Not wanting to scare you but they really are sitting ducks. But okay yes you start the count down when they commit 24/7 .Sorry, I know I am replying to an old post but fingers crossed!! You mentioned your muscovy duck sat only at night for 5/6 nights before sitting "fulltime". That is what my girl Daffy has done - she is now about to start week 3 of 24/7 (with normal breaks - food etc). What my question is - does any part of the night only sitting get counted into the incubation period - or do I start counting from the start of fulltime? Sorry if a dumb question but I have not done this before - to complicate things she is only about 7/8 months old and decided to lay under the house which we cannot access!!!!