Hi
 
As regards this, my gut feeling would be that something disturbed
your bees.
 
In my area it never gets cold enough for bees not to be able to
defend themselves, but  I have had rats come in and chew frames out
of weak/cold beehives. When their brood is disturbed they become a
bit odd at times.
 
What shapes were the white things in the cells between capped brood?
Are you sure they were not eggs which had undergone shape changes
from desication etc?
 
Another possibility is that your hive lid was slightly lifted for
some reason and the bees were then 'frozen' slowly, as to me it seems
unlikely that they would die so suddenly if hit by varroa.
 
I have had nuc attacked by rats on a number of occasions. young rats
(that have not been taught about bees yet) crawl into a hive with too
little brood to be aggressive and eat brood. The bees then just crawl
away. In my case they abscond. In yours I would think the cluster
would move up into the honey higher up. Honey is quite a good heat
sink, and warming the new living area may have been impossible
leading to them freezing??
 
Just some ideas
 
Keep well
 
Garth
 
---
Garth Cambray       Camdini Apiaries
15 Park Road        Apis melifera capensis
Grahamstown         800mm annual precipitation
6139
Eastern Cape
South Africa               Phone 27-0461-311663
 
On holiday for a few months     Rhodes University
Which means: working with bees 15 hours a day!
Interests: Fliis and bees
Disclaimer: The views and opinions expressed in this post in no way
reflect those of Rhodes University.