I know this has been asked a bazillion times, but how long should it take ducklings to pip through the outer shell once they've opened the inner membrane? It's been a couple of days since I noticed shadows in the air sac on candling and locked down the incubator, and I haven't seen any indication that they're starting to hatch yet. I know they were progressing as of yesterday because I checked two of them and heard them munching, but with all my recent reading about shrink-wrapped and drowned birds I'm getting nervous. I really expected to see some sign of pipping or movement of the eggs this morning, and there's still nothing visual happening at all, though we hear occasional faint chirping. I don't have a hatch date because these eggs were given to me partially incubated by a duck whose then-owner didn't even realize she had been setting on them. This is my first time trying to hatch ANYTHING artificially, and I coincidentally already had chicken eggs in the bator due the 13th. I figured they were all due to hatch within days of each other, but now I'm thinking the chicks may beat the ducklings out after all. Is there a time frame I should be aware of when the situation starts to enter the danger zone? If I could see even one little pip I would be so encouraged and relieved!