I posted a question recently in "solstice and bees" wondering what cues
prompted the resumption of brood rearing.  No one seemed to have any
opinions on the subject.  I will try to rephrase the question in hope that I
can encourage someone discussion.
 
*FACTS* (maybe premises would be better, open to debate anyway):
 
1.  Even if my posting gave too long a broodless period (Allen mentioned a
study that found some brood in every month except November I believe) there
is a period of time when the Queen stops laying (in Canada anyway).
 
2.  It is not temperature dependent because she shuts down before the
coldest period and resumes laying around the hardest time imaginable to
maintain brood rearing temperatures and at a time when having to heat a
little patch of brood can prevent the cluster from moving around and
maintaining honey contact.  If there is a temperature relation it is not an
obvious one anyway.  I believe where people put bees in temperature
controlled storage the pattern of brood rearing is maintained.  Anyone do
this that could comment?
 
3.  If light (day length) is the "cue" then the relation is also not
immediately obvious and I believe that the pattern is maintained even if the
bees are wintered in the ground or without light. (comment?)
 
4.  My experience with receiving package bees from NZ and Australia is that
they start to build up very similarly to packages we used to get from
Florida, despite the fact that they are coming from a place where brood
rearing was shutting down (I assume).  If there is a biological clock
regulating this activity then it seems that it can be quickly reset.
 
5.  There seems to be a genetic component to this "instinct", or to the way
it works.  I believe that my Carniolans have a longer broodless period than
the Italians I used to get.
 
I would be most interested in knowing whether I could add "internal clock"
to the long list of other remarkable abilities that the bees have and which
give me much pleasure to wonder at.
 
I also am curious as to what the situation is with bees in other locations
where there may not be a winter.  If there is a dry and wet season do the
bees start to raise a lot of brood in the period of nectar shortage at the
end of the dry season so that they will be strong when the flowers pop after
the wet season starts?  Someone in the southern US once posted that their
main flow was in the fall with not too much before that.  I wonder if their
bees still built up like mad in the spring the way ours do here, or whether
it was delayed.
 
Happy New Year
Stan