Slow colony spring population buildup compared to colonies in the same location that expand normally; heavy winter deadouts, some apparently due to starvation; colonies not storing surplus honey compared to others in the same area that do store harvestable surpluses.
Stress is a general condition that is hard to assess. In the spring, nutritional stress can take the form of colonies being weak. Such colonies may need feeding of additional sugar or protein. In the fall, inadequate nutrition may interfere with colonies rearing the “fat” (fatty body rich) bees that will be able to live longer during the overwintering period. Spring colonies that fail to build up in comparison to others may be nutritionally stressed, due in part to imbalance of adult populations with adequate nurse bees to feed young, or which lack a sufficient forager population to leave the hive to collect nectar and pollen resources. The spring diseases of European foulbrood, chalkbrood, or sacbrood may add to colony stress; large numbers of brood not advancing to adult stage can complicate buildup via failure to meet the normal nutritional needs for colony expansion. Environmental factors such as a cool, wet spring or shortened falls, can interfere with colonies meeting proper nutritional needs.
Spring nutritional stress is often due to inadequate pollen availability. Fall nutritional stress may be due to inadequate fall pollen resources to rear the overwintering bees and/or inadequate nectar resources to permit colonies to store sufficient honey for overwintering cluster behaviors. Nutritional stress in the summer may be due to inadequate nectar resources to provide harvestable surplus. Nutritional stress may be due to location, environmental conditions, including climate change, or from overstocking an area so individual colonies lack adequate resources. Inadequate understanding of colony buildup or nutritional needs in spring, summer, or fall may lead to inadequate management choices. This can take the form of harvesting too heavily, leaving colonies with too little honey stores.
Nutritional stress with slow colony buildup may result in colonies not storing harvestable surplus, or in comparison with other colonies not storing as much when supering is done normally. Nutritional stress may also occur with colony queen replacementqueen replacement:
removal of an old queen and installation of a new queen in a bee colony
, when there is a break in a colony due to queen replacementqueen replacement:
removal of an old queen and installation of a new queen in a bee colony
. It can also occur if queen replacementqueen replacement:
removal of an old queen and installation of a new queen in a bee colony
happens in spring buildup, when the colony division of swarming disrupts the normal distribution of worker age cohorts in the colony, interfering with worker sequence of duties (division of labor).
Although colonies may experience nutritional stress conditions, determining actual stressors or that a colony is under stress is extremely difficult. Mitigation is usually in the form of feeding supplemental carbohydrate and/or protein, reducing colonies numbers in an area or moving colonies to a more resource favorable area.
Branchiccela B, et. al. 2019. Impact of nutritional stress on the honeybee colony health. Scientific Reports 9(10156). https://www.nature.com/articles/s41598-019-46453-9.
Corona M, et. al. 2023. Decoupling the effects of nutrition, age, and behavioral castecaste:
reproductive division of labor within female bee adults; a single reproductive female queen (via pheromone secretions) maintains more or less sterile female workers
on honey bee physiology, immunity, and colony health. Frontiers in Physiology 14. https://doi.org/10.3389/fphys.2023.1149840
