I think Varroa is going to be blamed for a lot of the heavy winter losses,
when tracheal might be the real culprit. I have three hives and lost one
and the other two are weak but should recover. Since I have not lost a hive
in five years, I thought I was doing great. Two years ago there was not a
trace of Tracheal. Figured I had resistant bees. So no more crisco.
My guess is that there can be changes in the tracheal mite population which
would overwhelm even resistant bees. Give the mite even a slight advantage
and its geometric growth could easily tip the balance.
The larger problem here is that many beekeepers cannot tell the difference
between a winter kill by Varroa and one by Tracheal. It does require some
careful inspection. And since Tracheal has been relegated to the dustbin of
history by many, resistant Varroa is blamed where it may not be the
problem. If so, we can expect heavy winter kills next winter for the same
beekeepers who think their problem is varroa.

Bill Truesdell
Bath, ME