More information is needed. How long has the colony been in the hive? How
large is the colony? Do they appear to be quietly organized as a colony?
Do they sound queenless?
It is quite likely that a swarm moved into the equipment. The queen may be
a virgin and so small that you didn't see her. In a week or so she may get
mated and start laying.
It is unlikely that bees moved into the hive without a queen, but it is not
impossible.
James C. Bach
Yakima WA
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