From the time they pip the shell to the time they get around to doing anything can sometimes be more than 24hrs. Usually once they start zipping they are out in 20-60mins but occasionally You get slow ones that just make the hole a little wider or longer every couple hours. Occasionally you also get ones that finish zipping and then just sit there for awhile before they decide to push the end off the egg. Chickens are slow to finish hatching. That's why I don't help based on how long an egg has been pipped or the chick has been working on hatching. I go based on how far behind the others it is. If all the others have finished and that one has made no progress in 24hrs then I'll think about checking on it. Exception for completely zipped ones. I'll knock the end off those when I pull the dried chicks out because they are nearly always ready to come out and just haven't gotten the right position yet or the membrane is too dry and they got a bit stuck.
Internal pips into the air sac happen about 24hrs before you see pips on the outside of the egg. You won't see that though cause your eggs should be sitting in the incubator or hatcher undisturbed at that point. You might hear peeps if your lucky. I tend to have quiet hatches though and I've never heard a chick peep before it's broken through the shell.
Thanks, Gabrielle. Holly, do you mean it can take more than 24 hrs from external pip? I heard him/ her chirp about 6 hrs ago. two hours ago an external pip appeared (really tiny) and no action that is apparent from my window seat.
No one told me how surprising and beautiful that first chirp is!
Thank you Akane. Very well put. I know you've explained this to others before, but I couldn't find the post. I appreciate you taking the time to explain it to me. It sounds like it's doing fine, then, which is good, because I have no intention of assisting on my first hatch- I just totally lack the skill set at this point.
If he's made a hole in the outside of the shell he won't run out of air. Now that he has some air he'll rest for quite awhile absorbing the yolk and blood vessels. It will probably at least be hours if not tomorrow evening before the chick actually hatches.
It's possible the membrane underneath didn't break but odds are there's at least a tiny tear so the chick has stopped pushing on it. Sometimes they'll make an obvious hole but sometimes the pips are so minor it's driven me nuts looking from various angles trying to determine if that's actually a pip. Once they get the shell broken I think they can get some air through the outer membrane anyway because I had one nearly completely zip without breaking the membrane and after I raised humidity it pushed the end of the shell and tore through the membrane to finish hatching.