Soft shelled egg

[DukesDucks]

In one coop I have a drake with his 4 females, Muscovy ducks. There has been no changes to their feed, water, or routines, and they have a constant supply of oyster shells available. The last 3 days I have been finding 2 or 3 regular eggs in the morning, but finding a very soft shelled egg in the run in the afternoon. I have no idea which duck is laying them. I sat with the group for awhile today to observe their behaviour and everyone seems perfectly normal.
I would appreciate any advice.

 

[SmiYa0126]

Hello! I would dose all the females with calcium citrate tablet for a couple of days and see if that resolves your issues.

 

[Miss Lydia]

This can happen at the beginning or end of a laying cycle. Hopefully that's all it is.
Sure doesn't hurt to support with some extra calcium.

 

[DukesDucks]

This can happen at the beginning or end of a laying cycle.

That's what I was wondering. Cooler nights and shorter days. I'm going to start keeping better records so I remember from year to year.
As suggested, I'll add some extra calcium.

 

[DukesDucks]

Getting normal eggs again. I checked their bowls of oyster shell and discovered it was mostly the powdery stuff left. Dumped that and started over. This seems to have fixed the issue.