Dave I get the feeling that you believe that your evidence of CCD are these bees with cabin fever 
who are making cleansing flights and freezing up on the ground? 

how many years of experience do you have in over wintering your hives ? 

speaking from over a decade of wintering bees in central MN and sharing info with other 
stationary beeks up here I would say that anyone who keeps honeybees in the north with 3-5 
months of winter has seen this behaviour time and time again. IMO this is normal behavior during 
winter. 

From the FAQ's on CCD on the MAAREC website question number 1

"What is CCD? 

Colony Collapse Disorder (CCD) is the name that has been given to the 
latest, and what seems to be the most serious, die-off of honey bee colonies across the 
country. It is characterized by, sudden colony death with a lack of adult bees in/in front of 
the dead-outs. Honey and bee bread are usually present and there is often evidence of 
recent brood rearing. In some cases, the queen and a small number of survivor bees may 
be present in the brood nest. It is also characterized by delayed robbing and slower than 
normal invasion by common pests such as wax moth and small hive beetles. "
 
dead bees from cleansing flights in mid winter has nothing to do with the CCD symptoms 
described above.
 
i wrapped 280 hives before winter and every single yard has dead bees on the ground right now 
as they do every winter that we have "normal" subfreezing temps for months. as i mentioned last 
week I'd be very concerned if my yards were free of dead bees on the ground. 

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