Why are my bees all dead?

[Nirakaro]

Three hives - two Warre, one horizontal top bar - that were all well-stocked and apparently thriving when I checked them in November. Now still with many kilos of honey, and all full of dead bees. How do I set about figuring out what caused that?

 

[jenkinsbrynmair]

A few questions you might ask
When did you last treat for Varroa, and what did you use
What IPM do you have in place
Did you do any winter feeding
What was the purpose of the November check? what exactly did you do?

 

[Erichalfbee]

Can you post some pictures of the combs?

 

[Erichalfbee]

I think I’ll start a thread on this