I am wondering if I should be satisfied with that, or if I should tweak my incubation practices to try and improve it. I set 13 duck eggs and hatched 9, of which one may end up deformed (although it seems to be improving). That's a hatch rate of 60-69%. Here are my incubation conditions: Hovabator circulating air, with egg turner for the first 25 days 99.5 degrees F 50% (ish) RHumidity for the first 25 days 75-80% RH for the remainder Sprayed more-or-less daily from Day 7 to Day 25 with warm water Hatched in egg carton Eggs are from my own ducks, most were extremely dirty when collected and then washed gently. One egg quit before lockdown. Two appeared to have quit between Day 21 and lockdown, but I left them in just in case--neither has hatched. One egg seemed fine at last candling (Day 25), but has not pipped by Day 31. Incubator was opened once on Day 30 to remove day-old ducklings. Opened again that night to remove a deformed, stuck & distressed duckling for treatment. At the first opening, no humidity was noticeably lost--I sprayed with warm water upon opening, worked quickly, replaced the damp towel with a clean, wet one, then sprayed again and closed. At second opening, I may have lost some humidity, but I opened, grabbed, closed very quickly. This hatch and a previous one (also a 60% hatch) both were late and took a total of three full days to get everyone out. I can't think of anything else pertinent. Should I play with the humidity? Or be content with 60-69% hatches (I'm giving a range because I don't know whether to include the potentially deformed baby).