Sparsely spotted dead brood

[GSF]

A friend of mine sent me some pictures over to look at. Looking at the pictures I'm wanting to say chalk brood. About 2-3 out of 10 pupa are dead stuck to the side of the cell. They look somewhat deflated as in about half flat. They're still white. She did the rope test and got nothing. This isn't one given area in the hive, just sporadic.  Plenty of bees in the hive, stores, pollen, ect, ect, ect, all else looks good. Before the discovery we only had maybe 3 nights down in the upper fifties, which quickly warmed back up the next morning. We're in a drought, they are being fed. Goldenrod and fall flowers are blooming. Could it be that they decided to keep these to nibble on? If they died or were diseased wouldn't they have gotten them out of the brood nest? Thoughts, guesses?

[Oldbeavo]

Sound s like chalk brood, whether or not they clean out the dead ones depends on the Hygienic nature of the hive. Very hygienic bees will throw them out the front.
One of the things with chalk brood is to change queens, which is to improve the hygiene of the hive.

[Acebird]

Our club observation hive always had a problem with calk brood.  The hives hardly overwintered.  Maybe it was because they remain active but they can't go out and forage, I don't know.  An active bee only last a few weeks where a winter bee can last 6 months.  Maybe it was a dwindling effect.

[Hops Brewster]

I saw chalk brood in a hive at my friend's apiary.  It was a dink hive and he was considering replacing the queen anyway.  This was in late spring (when CB usually comes apparent), and after replacing her the chalk brood disappeared and the hive became a boomer.
Chalk brood actually look chalky because they are covered in fungus.
https://www.daf.qld.gov.au/animal-industries/bees/diseases-and-pests/chalkbrood

[BeeMaster2]

Our club observation hive always had a problem with calk brood.  The hives hardly overwintered.  Maybe it was because they remain active but they can't go out and forage, I don't know.  An active bee only last a few weeks where a winter bee can last 6 months.  Maybe it was a dwindling effect.

Brian,
I have an observation hive in my house.
Bees staying active in the hive during the winter is not causing the problem. All hives are active all winter long to keep the hive warm.
They may be trying to fly in weather that is too cold to allow them to return to the hive. That was one of the problems that Dadant had when he tried to keep his hives inside in a heated area.
Do they keep dwindling down in numbers or do they suddenly die off at some point?
Jim