This is my first try at hatching a duck egg. I actually wasn't even sure if it was fertile. What day do I need to lock down my bator and what does the humidity need to be? Right now the temp is a steady 100 and the humidity 60-65. It's day 8 today and it's developing fine. I wasn't sure if my baby boy Puddles finally figured out that he was a boy duck and NOT a chicken. Apparently he did. I got the girls in August and it was over a month before he quit being scared of them and running away from them. I really hope this egg makes it cause I can't wait to see what this duckling looks like...it's a mutt duck. Puddles is a Khaki Campbell/Rouen cross and the hen is a Blue Swedish.