You might also want to consider cold winter flight as being instinctual
behaviour.
What I mean is bees tend to prefer to die away from the bee nest during
times of good flight weather. They get old, they fly off to die. I
figure they do also during winter as they get a chance to break cluster.
I often find bees several hundred meters away from the bee yard laying
dead ontop of snow banks mid winter. I really doubt they are flying that
far to releave themselves. It has to be releated to something more
instinctual.
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