This year winter kill is higher than usual (15%) in Alberta. it is too early to get an average but I do not expect that will be like other years (30%). Our winter was harsh; 40% more snow than average and over 120 days with temperature less than -30 C. Some beekeepers reported high winter kill though they used various methods  for varroa control. However I reviewed with them treatments, but treatment time was too late. Therefore, varroa caused already its irreversible damage.  Treatment by that time did not help. Other beekeepers treated and winter kill was not bad. One new thing, I learned this year that is some wintering systems could not withstand our winter. Those beekeepers have to improve the system. It is not good to hear about bee kill. However, it is important to learn why!  Keeping records in our surveillance program helped us to answer many of these questions for some bee operations. The bottom line "Bees can't tolerate a short cut in management".  We also still have other possible causes of bee kill that are not fully known or understood.

Medhat    

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