> A few days ago I was inspecting the broodchamber, when I noticed a few black
> bees inside. I assumed these to be robbers and closed up the entrance again.
> However, since then I have seen black bees bringing in pollen and fanning.
> This does not seem like robbing so what is going on?

The mating of the queen with different coloured drones is one possible
explanation, but drifting is also quite normal if there are other hives nearby.

Bees often get confused about the location of their own hive on windy days or
when a beekeeper parks in front of the hives for a few minutes.  I also think
individual bees sometimes decide they do not like their native hive and emigrate
to the neighbouring hive.

In times of plenty, any bee that arrives may be accepted by most hives.  This
includes queens, workers and drones.  Drones in particular may come and go over
wide areas without hassle, but as many as 10% of workers normally drift in
apiaries -- depending on layout.

Another possibility is trucks with bees going by on the roads and losing bees
along the way.  Some time back Jerry mentioned some observations showing that
many bees find any local hives within miles in a very short time when lost off
trucks in good weather, and are accepted by them.

allen
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