This musing was authored by a beekeeper friend (Dave Cushman) who is not
yet fully up to speed with the Net and wished me to post it on his behalf.
Any replies may be sent to myself.
Cheers
Graham

Dave wrote:-

Two Queen cells?
 When queen cells are raised under supersedure impulse, they vary in
number between  2 & 6. (I have never seen less than 2 or more than 6  in
over 20 years and about 300 cases).
 Two is the most common...I guess about 60% of cases.
 The average is somewhere between  2 & 3.
 Two would seem to be significant to the bees for this purpose.
Possible Benefits:-
A, 2 could be a hedge against faulty development in either Q cell.
B, 2 Virgins could have the same or different fathers.
C, 2 gives the opportunity to choose one or the other by some criteria
that may be important to the bees.
D, It is possible that the option to swarm with one of the emerging
Virgins is kept 'in the back of the mind' by the bees. I do not think this
is the intention of the bees as swarming only happens in less than 5% of
cases and it is more probable that the case was not supersedure but was in
fact swarming impulse. The error being that of recognition by the beekeeper.
E, Other reasons as yet unthought of.
Questions:-
 If C, is valid then what characteristics do the bees favour?
 Do the bees value the same qualities as the beekeeper?
 Are the bees consciously maintaining or bettering their own
breeding or adaption to local circumstances?
Comments:-
 If a mating nuc is given one Q cell then it will accept it as the
only available option. If it turns out to be substandard or deficient in
some way the bees will supersede it in an attempt to correct the deficiency.
 If we give 2 Queen cells to every mating nuc then the bees would
have the same choice that they usually have in nature.
Choosing between Queens:-
Possible Mechanisms:-
Assuming that both cells and occupants are close in age and development.
1, The first queen to emerge damages the other cell purely on a chance
basis.
2, One Virgin is retained in it's cell by the bees whilst the other
one emerges and then damages the entrapped one.
3, Both Virgins emerge, seek each other and fight with no intervention
by the bees.
4, Both Virgins emerge and are kept separate by the bees while they
 assess the relative 'quality' of the Virgins. The deselected Virgin
is then harassed and killed by the bees.
5, Other mechanisms.
Conclusions:-
 If items 1 or 3 are correct then selection is random.
 If 2 or 4 is right we can assume that the bees recognise some
superiority in one of the Virgins.
Proposal:-
 That all Queen rearing and mating systems be changed to include 2
Queen cells per mating nuc.
Positive and Negative:-
Negative:-
 The use of 2 cells obviously requires twice as many queen cells to
be available as was the case before.
 The generation of early extra queen cells requires additional
pollen and honey resources and adequate nursing labour at a time in the
queen rearing calendar when such resources are scarce.
 It is possible that some swarms would issue with a 'spare' full
quality virgin. The smallness and lack of crowding in the nuc would be
against this but as mating nucs are necessarily an artificial system the
possibility cannot be ignored. I have only ever had swarming from a mating
nuc when testing mated queens for brood rearing ability. These swarming
nucs consisted of 10 or 11 half width, full depth frames in half width
National brood boxes. I have not yet tried the 2 cell idea myself but I
intend to do so quite thoroughly over the next 3 years.
Positive:-
 If bees are able to make 'quality control judgements' then the
average quality of commercially/artificially reared queens would rise.
 The rate of 'BEE IMPROVEMENT' would speed up as I believe that the
bees would make better choices than the beekeepers.
 There would be fewer 'poor quality' queens and less disturbance to
developing colonies that would otherwise have been superseding such a poor
quality queen.
 The provision of extra queen cells would not be difficult,
particularly in high summer. When I use the Jenter or Nicot cell plug cages
I rarely use more than a third of the available larvae. A few extra cell
starting and cell raising colonies would be a small price to pay
for 'better bees'.
 I feel that the possible benefits outweigh any unsatisfactory
features by quite a large margin.
 I also intend to try raising pairs of Q cells within the mating
nucs themselves using special frames with small reservoirs of pollen
(freshly trapped from full size colonies) and other small reservoirs of
50/50 honey & water + 0.1% copper gluconate. I do not know if the bees
prefer cells they have raised themselves but I suspect they may.

Dave Cushman