Stephan Braun on the island La Palma in the Canary Islands shows us how he has aquired resistant bees against the Varroa mite. Read his website and learn how he is doing. He works with the native Canarian bee, which might is a variety of the Iberian type.
After he took his bees down on small cell size, 4.9 mm, the bees behave in a more harmonius way and they behave in a much more calm way, so he doesn’t need all the protection utilities he needed before. Of course selecting and breeding have made contributions here.