Here is an interesting read, supporting limited or non-treatment of bees for their various parasites and how treating can slow down genetic change allowing the honeybee to deal with them. It scientifically shows how the honeybee has adapted faster with no treatments than with medication.
They talk about “unmanaged bees”, I wonder what that means really, what is their definition of a “natural” honey bee. One assumes that the hive is not medicated or treated. I did not see a discussion of whether or not they are using foundation, what the cell size might be, or if they are using natural comb. I would love to ask them that question! It does look like they are hanging a good chunk of colony collapse disorder on the varroa and the associated vector diseases. I hope that they come out with further studies.
Good find Paul!
I am not convinced that cell size by itself is the key. I think that several factors in combination seem to be the reason. There also seems to be a tipping point you reach in the number of hives and bees where cell size and treatment free no longer works - much like the famous experiment with the rats in the sealed box. At that point you cross the line from small scale to an industrial operation and lose control and have to treat.
I am also more and more convinced that the "wild" nature of certain strains of bees plays a big part of parasite control, and by eliminating feral colonies for fear of "AHB" we are actually harming the future of our honeybees. It's a losing battle not worth fighting and simply slows evolutionary progress.