Continuous hive monitoring reveals colony growth and activity differences among mite-resistant and Italian honey bee stocks

Authors: Meikle, William; Weiss, Milagra; Ricigliano, Vincent

Submitted to: Apidologie
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/6/2025
Publication Date: 6/20/2025
Citation: Meikle, W.G., Weiss, M., Ricigliano, V.A. 2025. Continuous hive monitoring reveals colony growth and activity differences among mite-resistant and Italian honey bee stocks. Apidologie. 56. Article 61. https://doi.org/10.1007/s13592-025-01188-7.
DOI: https://doi.org/10.1007/s13592-025-01188-7

Interpretive Summary: There are many different varieties of honey bees, and the choice of variety can be important to beekeepers because different varieties behave different ways. Here we monitored three different varieties, including two varieties known to be resistant to Varroa mites (an important bee pest) and one that was commonly available from commercial breeders. We found that hives with the mite resistant varieties gained weight faster in the summer and lost weight slower in the winter than the commercial variety. We also found that one of the mite resistant varieties had smaller colonies (fewer adult bees and less brood) than the commercial variety, and one of the mite resistant varieties maintained higher CO2 concentrations than the other mite resistant variety. Finally, we found that the commercial variety had much higher mite levels than the mite resistant varieties. This information is important for commercial beekeepers because the mite resistant varieties may provide more honey with less need for mite control measures.

Technical Abstract: The choice of honey bee genetic stock represents an important management decision for beekeepers to improve resilience against biotic and abiotic stressors impacting their operations. Three different genetic stocks of honey bees (Pol-line, Russian and Italian) were monitored in southern Arizona field experiments for two successive nine month periods (June to Feb.). Continuous monitoring techniques and detailed hive assessments were used to measure differences in colony performance and behavior. On average, Italian colonies produced significantly more brood compared to both Pol-line and Russian bees and had significantly more foragers and adult bees on average than Pol-line colonies. However, both Pol-line and Russian colonies exhibited a faster rate of weight gain during the primary nectar and pollen flow season (June-Sept.) and slower weight loss during the dearth season (Oct.-Feb.) compared to Italian colonies. Pol-line colonies started flight activity 10 minutes later on average than Italian colonies and ended daily flight activity about 30 minutes later on average than Russian colonies. There were no internal hive temperature differences among bee stocks, but Pol-line colonies maintained the highest CO2 concentrations. Finally, Varroa mite levels in Pol-line and Russian colonies were significantly lower than Italian colonies. Our findings highlight the potential advantages of Russian and Pol-line bees for use in commercial beekeeping operations. These observed stock differences could translate to improved crop pollination efficiency and reduced reliance on chemical mite controls.