I do about 50% humidity throughout incubation adjusting as needed based on the size of the air cell/the weight the eggs lose. If the air cells are too small through the second half of incubation, you can mist the eggs with warm water daily which will help them to lose moisture. If too large, you can increase humidity. At lockdown, this humidity rises to about 65-70%.
To adjust humidity, you can use a dish or container of water (with a grid of something over at lockdown to prevent babies falling into it), though most incubators have compartments to put water in.
You will need a calibrated hygrometer in tbe incubator and this will tell you what the humidity is. You can adjust it from there, but remember it isnt the depth of the water that matters much, its the surface area. The larger the surface the higher humidity.
Temperature is 37.5 Celsius throughout incubation and lockdown, that doesnt need to change.
Unless hatching muscovies, lockdown is day 25. 3 days before hatch. That is when you remove the turner, set the eggs down and increase humidity. Then you leave them be and wait for the hatch.
If hatching calls, they often hatch at around day 26, so you would keep an eye on them and perhaps lockdown a day or two early if they start rocking or internally pipping.
During lockdown after day 25:
Internally pipping is the first stage of the hatch, there is an internal membrane blocking off the air cell, when the duckling is ready and in position, they will pierce this membrane and begin to breathe.
It can be a while later that they then externally pip (break) the shell.
If after 18-24 hours there is no external pip, the baby could be at risk of running out of air in the shell- and may need a pin hole in the air cell. But you must be very very careful doing this-you can resort to this
Assisted hatching article
But beware, ducks take a very long time to complete hatch. After the external pip, the duckling may stop progress for up to 48 hours. Then, once its yolk and blood vessels are absorbed, they will zip.
This is where the duckling rotates in the egg, breaking the shell in a circle. Then they will pop the top off and hatch out!
Zipping shouldnt take more than a couple hours but in my experience they can take longer, especially if they get stuck.
Again, the hatching article will tell you all you need to know about how to help if you choose to if any of them gey stuck.
Good luck
