Dark Spot on Egg

[joneschickenmama]

Hi, I hope this is allowed. I'm asking about duck eggs. I went out & got eggs this morning out of my duck coop & found 4 eggs in their nest with dark spots on them. I'm fairly new to raising ducks. I have no idea what the spot is? Does anyone know or have any suggestions? Thanks in advance.

 

[Weeg]

Who long have the egg been sitting out there, what temp is it where you are? What does 1 look like cracked?

 

[joneschickenmama]

They were just there overnight. It's in the 60-70's during the day & 50's in the evening. I haven't cracked one yet.

 

[joneschickenmama]

I have 9 eggs like this total.

 

[aart]

Is the bedding wet?
How do they look inside?
Does the dark spot have a thinner shell?