I have a female duck that randomly let's out a series of 4 or 5 extremely loud quacks, it almost sounds like she is stressed about something! I have not found any of her eggs in several weeks, I'm not sure if something is eating them or if she's not laying? How would I know if she is egg bound? I moved to a new home and built a new coup but she has layed in the new coup so I don't believe it has anything to do with it.