I put up 2 Wood Duck houses on a small Southeastern Wisconsin lake about 3 years ago. I've had Woodies use them every year, though one of the them always turned out to be a "dump" nest and no hen ever brooded the eggs. This year one box turned out to be a dump nest and the other one was actively brooded by the hen. She laid 14 eggs and just yesterday (July 4th) did the chicks hatch and leave the box. 7 hatched and 7 were infertile. I checked the box on the 3rd and the eggs were just starting to pip and I could hear the chicks in the egg, so I knew hatching would occur in the next 24 hours. She must have called them out very early on the 4th as I didn't see them jump. I have 2 observations and wonder if anyone else has any input. First of all, this is quite late for a brood hatching but I know Woodies are the only duck that will attempt 2 broods in a season, and secondly, how does the hen know when the last chick is out of the box. She doesn't return to the box to check. It's like intuition or something. Anyone with an opinion?