Allen, and all:  The queen introduction boards (QIB) I use are of three
designs.  a) a single piece of 1/8 hardware cloth on one side of the 4x9
hole cut in the center of the  plywood or, b) a piece of 1/4 in. plywood
with 1/8 in. wide saw kerfs or, c) a piece of peg board with 1/4 in. holes.
 This ventilation is suspected to allow the movement of heat up to the
small nuc allowing for a faster build up.  I am of the current opinion that
not only does heat pass up to the small nuc on top, but I think that even
if the bees cannot communicate directly (I'm not sure how much
communication goes on through the 1/4 peg board or the saw kerfs), the bee
behavior changes resulting in a higher production.  I am at a loss to
explain the reason why a nuc on top of a piece of 1/4 solid plywood
(without any hole) results in the same honey storing behavior as those with
a screened hole.  In fact I have even removed the QIB and find that the
bees continue to store honey in the same manner i.e., more evenly
throughout the supers, vertically between the two queens.
 
I operate with three or four westerns as the bottom brood nest, and two or
three containing the top queen, depending on how good the top queen is,
with three to five westerns as supers between the two queens.  A good queen
needs three to avoid crowding before the July 5 date when I like to combine
the top colony down.  If the lower queen fails I move the top colony down
to replace her.
 
My goal with the 2-queen colony is to produce two or three more westerns of
bees to bring in the end of the honey flow after I combine the two
colonies.  Another observation I and others have repeatedly made is that if
the lower queen appears to be failing i.e. poor brood pattern, when you set
up the top nuc the bottom queen (or the bees) changes her behavior
drastically and quickly.  A poor brood pattern changes to a dense brood
pattern within one brood cycle.  I can't identify the cause of this.  Often
the lower queen disappears within 3-4 weeks after the top queen is put on.
I know this occurs because I use marked queens and track their longevity.
This increased brood production must account for some of the increased
production of the hive.
 
I theorize (emphasis here), that queen pheromone constituents are not all
tactle in nature, but indeed judging by observed bee behavior, some
constituents must be olefactory.  Further, If a second queen is added, some
elements of queen pheromone must impact bee behavior, maybe even urging the
nurse bees in the lower brood nest to better feed (?) their mother, which
may result in more egg production, or better feeding activity, which
results in increased survivability of the brood.
 
To reply to your query about the solid QIB resulting in one hive set on top
of another, I agree.  BUT, I have visited an apiary where 40 three frame
nucs (singles) were set up in early May.  I visited in early August as I
recall.  Opening a lot of the nucs I noted that most were less than three
combs of bees at the time of my visit.  Adequate food stores were in each
hive.  I observed 40 percent queenless colonies, most not having made any
attempt to supercede.  I also observed many other aberrant behaviors of the
bees.  In the center back of the apiary were two hives which were two
stories high.  Opening the hives I observed them to be crammed full of
bees, quiet in behavior, queen retinues, and all the other normal and
desirable behaviors.  Based on these behaviors I strongly suspect that bees
from the other single story nucs in the apiary had migrated to these two
attractive queens.  I and others have seen these behaviors repeatedly over
the years.
 
It is my opinion based upon a multitude of observations, that attractive
queens result in a more productive colony, and two queen systems create
this environment by increasing queen pheromone levels at both ends of the
storage chamber, and also an result in an increase in brood production.
 
James C. Bach
Yakima WA 98902-6108
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