I see you are in SA.
According to Gloria DeGrandi-Hoffman, both Africanised queens and Africanised
worker groups have been observed in the USA invading other hives, taking them
over, and displacing the original queen.
Could this be happening in the hive in question?
allen
http://www.internode.net/HoneyBee/
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No matter how cynical you get, it's impossible to keep up.
> By sheer co-incidence, or luck, I was checking out a hive with an
> extremely valuable queen and found her balled; badly balled.