>>you need extra bees to get a cluster through the winter. death is part of the cycle of life in keeping bees upnorth...
Is anyone checking for or trying to control tracheal mites? I think I have tracheal mites which ground a good number of bees in March. The barely flying weather can bring a 50% drop in population (it seems the bees are [barely?] alive as long as they stay in the hive). It seems to me the perishing bees take a lot of t. mites with them. The colonies build up nice otherwise and go through the season with good results.
This sort of steep 'spring dwidling/cleansing' cleansing is ok. 4-5 frames of bees at the end of March will get the hive ready for the flow on May 1st.
I have heard that bees have more resistance of tracheal mites. Through the selection from the strongest colonies, I hope to get more and more resistant bees to tracheal as well as varroa mites.
Waldemar
PS. I am working with a friend of mine who has access to a microscope to verify the presence of t. mites.
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