Climate-Smart Agriculture and Cold Storage Practices: Exploring Sustainable Solutions for Honey Bee Conservation

Beekeepers in Pennsylvania face a critical challenge marked by overwintering colony losses that consistently surpass 40%. Survey efforts show that, nationally, 28% of colonies die each winter, on average (Bruckner et al. 2023). Mortality during the summer is also significant, with 18-32% mortality reported in a recent article (Bruckner et al. 2023). This alarming trend raises significant concerns about the long-term economic viability and sustainability of beekeeping. Many factors are at play here. One crucial factor is climate change and the unpredictable weather that has come to be the new normal. Fluctuating temperatures are stressful for honey bees, who struggle to maintain consistent nest temperatures, and for the flowers on which bees depend for food. These fluctuations are especially stressful during the colder months of the year. For example, Becsi et al (2021) showed that 20% of the fluctuation in winter mortality can be attributed to weather conditions. One progressive approach to mitigating the impacts of temperature fluctuations is the utilization of climate-controlled storage for honey bee colonies. The adoption of climate-controlled storage holds great promise as it offers multifaceted benefits, encompassing improved colony health and survival, novel means of pest control, and, subsequently, increased economic viability of beekeeping (Hopkins et al. 2020). 

The temperature fluctuations driven by climate change during the period from mid-October through mid-December create favorable conditions for a behavior known as robbing among honey bees and by yellow jackets. During this time, opportunistic insects attempt to pilfer honey reserves from weaker honey bee colonies. Robbing opens avenues for the transfer of parasitic varroa mites, pathogens, and various diseases between colonies, exacerbating health challenges in already stressed bee populations. Managing and mitigating the impact of robbing incidents is essential to safeguarding the overall well-being of honey bee colonies in Pennsylvania. As a case in point, during the fall of 2023, beekeepers in PA have described feeding their colonies gallons of thick sugar syrup in an attempt to bolster winter reserves only to find that, when hives were weighed after feeding, instead of being heavier, they were lighter. A combination of robbing by yellow jackets that were not halted by frost and a dearth of the usual fall sources of floral nectar conspired to cause this issue. Beekeepers are now scrambling to provide carbohydrate reserves for the winter, at great expense in terms of labor and resources. If these colonies had been moved into cold storage in early October, we believe they could have avoided robbing by yellow jackets and would have shut down brood production, allowing for improved food storage. We intend to test this with the funds for this project. 

Climate-controlled storage for honey bees presents a versatile solution that can be readily integrated into beekeeping operations of varying sizes. Not only can bringing bees into cold storage mitigate robbing issues in the fall, but the temperature and humidity-controlled units can be used year-round for various beekeeping activities. During this project, we will investigate the uses of cold storage units not only for overwintering full-size colonies, but also as a means of overwintering mated queens. Mated queens are hard to come by when they are most needed - in April and May. This results in the importation of queens from southern states. If, instead, queens can be overwintered in groups, called banks, they will be ready for sale in April/May, providing northern queens for northern beekeepers. We intend to overwinter banks of mated queens to investigate their survival and health. Cold storage units can also be used by beekeepers to warm or chill beekeeping equipment, depending on the need. We will use the units to heat honey prior to extraction, for ease of processing. We will also cool boxes of honey to kill pests, such as wax moths and small hive beetles, and to preserve the honey as the beekeeper prepares to extract it. These units will be a great benefit in these situations, making the units economically valuable.

This technology holds immense potential for the future of beekeeping, particularly in the face of ongoing climate change. As the challenges posed by shifting climate patterns persist, the adoption of climate-controlled storage stands as a promising strategy to bolster the resilience and sustainability of beekeeping in the mid-Atlantic region.