Hi:

Use of 1 versus 2 queens is often hotly debated - mostly in the absence of
hard data.

The following is personal opinion based on 30 yrs of experience, both from
our research and observations of 1 and 2 queen hives in commercial and
hobbyist operations.

1.  Although colonies usually tolerate only one queen, we have seen many
colonies with two queens, both nucleus and full-sized commercial - with no
elxcluders and no intent by the beekeeper to run a two queen colony.

2. We expect 20-30% or more of the queens in colonies to supercede before
the end of the summer (most of the colonies that do this, do so when the
queen excluders are put in place or when extra supers are dropped on the
hives).  And , we have the numbers to back up this observation.

3. Colony management varies greatly from one part of the U.S. to another.
What works for you may not work for someone else.  The most successful 2
queen operations that we have seen, start with two queen colonies, then go
to 1 queen by end of season - 2 queen colonies have split clusters and
often don't overwinter well.

4.  My guess is that reports of better production with two queen are simply
a reflection that the colony will always have at least one queen present
during the growing season.  Queen less colonies stop thermoregulating,
often stop gathering pollen, and even if a new queen is produced, you have
a lengthy brood break - which slows down the colony dynamics.

5.  If you tightly manage colonies and quickly replace failed or lost
queens, 2 queen system probably are of little or no benefit.  If you can
only occasionally get to your colonies, 2 queens may be a form of insurance
policy.

Cheers

Jerry
Jerry J. Bromenshenk, Ph.D.
Director, DOE/EPSCoR & Montana Organization for Research in Energy
The University of Montana-Missoula
Missoula, MT  59812-1002
E-Mail: [log in to unmask]
Tel:  406-243-5648
Fax:  406-243-4184
http://www.umt.edu/biology/more
http://www.umt.edu/biology/bees