A recent study published in the Peer Community Journal and titled "Brood thermoregulation effectiveness is positively linked to the amount of brood but not to the number of bees in honeybee colonies" sheds light on the factors influencing the effectiveness of brood thermoregulation in honeybee colonies. The findings provide valuable insights into the role of colony size and meteorological conditions in maintaining optimal brood temperatures.

By using methods of experimental setup, colony monitoring and data analysis, the authors of the study, amongst whom B-GOOD researchers Ugoline Godeau, Maryline Pioz, Yves Le Conte and Cédric Alaux, monitored 29 honeybee colonies over a period of two years. They regularly measured both brood and adult population size over the beekeeping season and monitored the brood temperature over the 24 hours preceding the inspections of these colonies. The effectiveness of brood thermoregulation was evaluated via two criteria: the accuracy of the brood temperature and the stability of the temperature around the mean value.

Figure from article: Mean in-hive temperature (MeanT) predicted by the average model as a function of the observed MeanT, with first bisector in blue (Predicted MeanT=Observed MeanT), deviations from this line in grey and regression line of the point cloud as a dotted red line. 
 

The results revealed a strong correlation between meteorological conditions and brood thermoregulation. Additionally, the study found that the amount of brood had a positive impact on the mean brood temperature, while the stability of the temperature did not appear to be influenced by the number of bees in the colony. The study highlighted the remarkable ability of honeybee colonies to effectively regulate brood temperature, regardless of colony size.

To fully understand the potential of brood temperature as a proxy for estimating colony size, the researchers recommend further analysis of a wider range of colony size variations, including depopulated or collapsing colonies.

Read the full article here.