They're dead!

[Jon]

More information on acarine.

Acarine disease shortens the lives of adult bees, affects flight efficiency, and causes a large number of crawling bees that are unable to fly. In extreme cases, colony populations often dwindle and, ultimately, the colony dies. Infested colonies may not develop normally and may exhibit symptoms of dysentery and exhibit an excessive swarming tendency. Often, however, severely infested colonies appear normal until their death during the winter. Colonies are most affected during winter confinement and early spring as with other stress diseases. Mite infestations are at a maximum in the early spring when the population is comprised of primarily older bees. Only old and heavily infested honey bees are killed by the mite. Whole colonies that have more than 30 percent of the individuals infested are often destroyed during late winter.

http://msucares.com/pubs/publications/p1753.htm

[GRIZZLY]

Interestingly,Gavin,the "newly"emerging bees have all got protruding tongues which suggests starvation,your brown gunge/scale is probably the end product of the sac brood in the colony earlier.I had a colony die out and looked like your photos-I put this down to being very small and therefore getting chilled.Mine also had lots of sealed stores very close to the bees but I think far enough away to allow them to starve in the exceptionally cold winter we've just had.If you remember I raised a question concerning Acarine on another forum but got "shot down" and "poo pooed" by the learned folk - such suggestions as "Varroa treatment will kill-off Acarine " etc.etc. The K wing I had spotted in my apiary was put down to "Varroa.,virus " and other pathogens - I'm not convinced and intend to 'scope a sample later on when there are a few young bees about.I think there well might be an upsurge in acarine especially as Folbex has been outlawed from our armoury.