Intelligent Bees Remove Varroa Mites?

[picton farm]

Sorry about the fantastic headline but this seems too good to be true so i wanted to share.......
I was talking to an elderly beekeeper a few days ago and he told me his bees had for the last 3 years been removing all the early drone brood until May. After that they leave it alone. He also mentioned that he found the levels of varroa to be higher at the time they were doing the clear out and that subsequently the colonies seemed more or less free of mites.
Is it possible that the bees have worked out that there are a lot of mites in the drone brood and are removing them? Is this common?.......

.........Running for cover now.......ok safely in my bunker......open fire!

 

[Midland Beek]

If the workers did not want to raise drones I think they would ordinarily destroy the eggs rather than investing all the effort into rearing them only to then kill them before they emerge.

I am inclined to suggest workers would only abort brood - worker or drone - if it has died and/or is highly infested with varroa.