Thanks for sharing your information Jim. 

Have you considered that the hives that swarmed had a low population of winter bees going into 
winter?  That would not directly explain the nosema but winter may have  been more stressful on 
"old" bees which made them more vulnerable to a Nosema outbreak? 

Here in Mn I have seen a correlation with wet winters and Nosema losses. Especially wet weather in 
Feb and March. 

In fact here in Mn/Wis you can draw a line SW to NE across the two states and based on anecdotcal 
reports it appears the losses were very high on the wet side of that line.  The difference in precip on 
either side of that line was significant. 100 inches plus on one side and 30 inches of so on the other 
side.   Can anyone from those states validate that theory or debunk? 
 

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