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
[log in to unmask]
[log in to unmask]