Hatching duck eggs - first timer!

[Tmarie2020]

I put 9 silver appleyard eggs in the incubator (Brinsea Maxi Adv) on Feb 13.
I stopped turning on day 26, temp 98.5, humidity 65-73%.
Half started pipping on day 28.
One has hatched as of 3/13, with several rocking today.
I am curious about the two eggs I have that are super dark (photos below). What is that? One has definitely pipped and the other I can’t confirm.
At this point I’m planning to leave all eggs alone until this evening, possibly tomorrow AM before moving them to the brooder.
Really just reaching out for tips, advice in general.
It seems like their hatching process has been pretty drug out, I’m welcome to tips that would make it easier on them.

 

[Yardmom]

Ducks take a bit of time to hatch. Not unusual for it to take a few days. I would have guessed the eggs that were dark to not be good but you mentioned one piped? How many ducklings so far?

 

[Tmarie2020]

Ducks take a bit of time to hatch. Not unusual for it to take a few days. I would have guessed the eggs that were dark to not be good but you mentioned one piped? How many ducklings so far?

I have two ducklings, one just hatched with the belly button protrusion (I understand this means it hatched too early??) and there are two more still in the egg.

I’m wondering if the 28 days was simply too short for this breed. If I hatch again, I will definitely plan on another 4-5 days before lockdown. What’s your experience?

 

[Tmarie2020]

Ducks take a bit of time to hatch. Not unusual for it to take a few days. I would have guessed the eggs that were dark to not be good but you mentioned one piped? How many ducklings so far?

To clarify, should I have budgeted more time for incubation, or just the hatch in general?

 

[New duck mommy 2021]

I have two ducklings, one just hatched with the belly button protrusion (I understand this means it hatched too early??) and there are two more still in the egg.

I’m wondering if the 28 days was simply too short for this breed. If I hatch again, I will definitely plan on another 4-5 days before lockdown. What’s your experience?

28 days is by the book
But like any other baby that hatches the book isn’t always perfect
I don’t use day 25 lockdown
I watch my eggs
When I see shadowing pushing on the air cell. The eggs rocking around the bator and the air cell jumping forward fast
That’s my signs for lockdown
It can be say 23 or 27 I go by my eggs
As for what causes later hatches
Higher humidity during incubation and lower heat
Even being off a little can cause delays
The high humidity gives smaller air cells as egg looses less weight and baby’s aren’t forced to hatch with the extra room
Running higher heat and lower humidity has the opposite affect
Air cells get way big and baby’s develop faster
Then you will see earlier hatching as they run out if room faster. Hope this helps
Calibrating both thermometer and hygrometer helps to get more accurate results
Often the bators readings are off