I think those are great hatch numbers! Do you think it strung out because it started late, and do you attribute that to slightly low temps?
I have one that shrink wrapped that was one of the first two pipped when I moved eggs to the hatcher for today's hatch (26 Production Reds and 2 Silkies). I still think the temp in my Brinsea is a hair high, and will adjust down a tick again. At bedtime I had 5 hatched, this morning at 4 I had 8 hatched and 3 pipped, now 3 more have pipped. Since they are not due until today I think they incubated a little high. Silkies hatching early never surprises me but these egg layers laid within 30 miles and maybe a few hundred feet elevation should have been right on time, or at least I thought so, but then again it might be the low air pressure too. If I go lower to get them to hatch later, do I run the risk of letting the chicks get too large before they try to hatch and decrease the possibility of live hatch?
The main reason it strung out is because (like a big dummy) I set eggs on 3 consecutive days. And yes, I do think the temps were low because even fresh eggs hatched slightly late. I'm still trying to understand exactly how my incubator functions even though I designed it. I keep taking notes and will eventually write up my owners manual.
It's a unique design but it has had lots of tweaks, redesigns and remodels after each attempt. Accurate thermometers really did the trick this time around.
Perhaps it would have been better if I was better about egg collection and storage techniques. I carry eggs in thinking I may set them and then don't separate, date and mark their pedigree.
I'm pretty pleased with the fertility of untested roosters, especially this time of year. I keep them confined till after 8 AM to give the neighbors a break. I can't even hear the roosters if they're outside when I'm in the house. My 2 closest neighbors told me they didn't even know I had chickens, much less roosters.
I was going to suggest that your temps were probably a little high.
I would think there are two primary issues, pressure and lower ambient oxygen.
I'm not an expert at high elevation incubation but hope to become one.
I'm not sure I could take the stress! There seems like a lot to it. How in the world does a hen EVER hatch a single egg. LOL. It seems like a great science project for the kids though. My sister has an incubator, so I could give it a whir I guess. Again, it was very interesting to see the progress/results of everyone hatches. Thanks!
The stress is WAAAY lower with a hen.
I think they do it well because they've been doing it for thousands of years - it's just nature. We just started in the last couple hundred years so we humans are still trying to learn.