Photoperiod is likely the primary cue at latitudes where light:dark 
periods at the solstice differ by a good number of hours.  In areas 
where the ratios are more similar, other factors may modulate more 
strongly, or hide the effects of photoperiod.  Around 32 degrees N 
(southern Louisiana, Houston) most colonies have a broodless period of 
about a month, centered around the solstice.  Manipulations like 
opening and smoking, or moving colonies can initiate brood rearing.  At 
greater latitudes (38 and higher), the broodless periods get 
progressively much longer, still center around the winter solstice and 
are probably more difficult to interrupt with manipulations or feeding.

Avitabile (Journal of Apicultural Research, 1978) summarizes his 
findings from studies in Cornell, NY:

From November to March in three consecutive winters, experimental 
colonies of honeybees were killed; eggs, larvae and pupae in them were 
counted, and adult bees were weighed. The average number of adult bees 
declined steadily from 20 800 in November to 12 000 in March. The 
amount of brood in the colonies was small prior to the winter solstice, 
but increased rapidly afterwards. It is believed that the brood-rearing 
cycle in the honeybee is controlled, at any rate in part, by changes in 
daylength.

John Kefuss (same journal, same year) ran colonies in chambers with 
different photoperiods and found that more brood was produced with 
longer daylengths.

 

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