Honey bee colonies confined to winter quarters were monitored from 5 December until 11 March to assess changes in sealed brood production, colony demographics and adult populations during winter confinement. Small amounts of sealed brood were observed to be continuously present in colonies throughout the winter. Enough brood was reared during the winter to produce a small but temporary increase in the adult bee population and to replace most of the adults that died during the winter. Requeened colonies produced slightly more sealed brood during winter than colonies that had retained their original package queen. Approximately 34 - 50% of the adults in colonies in March had been reared during the winter. In March, the average adult colony was composed of workers that ranged from a few days old to 192 days of age. Average spring adult populations were 13,274 ± 1,078 (range 5,000 to 20,746).