Small cluters of bees outside the hive in cold weather

[dhabliston]

We have been fondant feeding two strong hives that are protected with a roofed open structure for the last month.  This last week in 40 F weather I found several small clusters and individuals on the outside of the hive body.  They are near motionless but apparently still alive.  The main colony is foraging normally and bringing back Hazelnut pollen.  The second hive has not shown any abnormal behavior.  Does anyone know why these bees are congregating outside in cold weather?  How to correct the problem.

[FRAMEshift]

Where are you located?

[dhabliston]

Eugene, Oregon USA