It was December 2009, and I was probably just longing to have some contact with my precious bees, even dead ones, and decided to look how many mites I could find in hive bottoms.

I had no plan whatsoever for the future. After counting thousands of bees found out that they had in average 11% infestation. Wrote some notes.

Time passed and I had forgotten all about this incident in 2009. Date was December 2017 and I, for some unknown reason, found myself again counting mites in dead bees. Thousands of them.

 While doing I faintly started to remember “Haven´t I done this before?”  

And my surprise was big when, after going thought my notes, found out that infestation in 2017, 4,3%, was 60% less than in 2009.  Can this be a sign of breeding efforts succeeding?

In December 2020 my curiosity had risen so much that I had to do the same experiment again. I checked 942 dead bees. They had 2,4 % infestation level, 45% less than 3 years earlier!

I want to firmly point out that this is no science, nothing near, but in my mind something better than nothing.

If average infestation in bees flying out to die is greater than among living bees still in winter cluster, one could argue that infestation in varroa resistant bees is somewhere from almost zero to 2%.  

Juhani Lundén