The effect of requeening in late July on honey bee colony development on the Northern Great Plains of North America after removal from an indoor winter storage facility

The effect of late summer requeening on the subsequent development of honey bee colonies during autumn (Harris, 2008b), and when confined in an indoor wintering facility (Harris, 2009) was extended with observations on sealed brood production, colony size and colony demographics every twelve days from 11 March until 14 August after they were removed from their winter quarters. Average adult populations declined for the first 48 days, and then recovered over the next 24 to 36 days once adult emergence consistently exceeded worker mortality. Rates of mortality for wintered workers were similar to those recorded for bees emerging in April, May, June, July and most of August. The last surviving bees from worker cohorts marked in September and October 1976 died between 3 June and 15 June 1977. Requeening treatment effects were quite variable and not statistically different. Requeened colonies were, however, generally larger than those headed by older queens when the experiment was terminated on 14 August and these colonies were killed and counted. The nine largest colonies belonged to the requeened treatments and contained on average 8,637 more bees (range 85 to 17,735) than the largest colony that had not been requeened. One of the requeened colonies was estimated to have contained slightly more than 80,000 adult bees at its peak population on 9 July.