Feasibility and effects of a nano-scale feed supplement on honey bee colony performance during blueberry pollination

Abstract

 Highbush blueberry (Vaccinium spp.) production relies on pollination by the European honey bee (Apis mellifera (Linnaeus, 1758), Hymenoptera: Apidae). Yet, recruiting honey bees to blueberry flowers can be challenging due to floral traits that limit access to nectar and pollen. Beekeepers have also become increasingly reluctant to rent colonies for blueberry pollination because of concerns about post‑pollination declines in colony health associated with brood diseases and pesticide exposure. Nutritional supplements formulated at nano‑scale that can be readily consumed and shared through trophallaxis offer a promising yet understudied approach to improving colony performance and overall health during pollination in open‑field settings. This exploratory pilot trial evaluated the feasibility and potential impact of an easily deployable nano‑scale feed supplement, Nano‑B‑Feed™, on colony growth during blueberry pollination and returning forager activity. The trial occurred in a commercial 'Duke' blueberry field in northwest Washington, USA, using 30 colonies distributed equally between a Nano‑B‑Feed™ treatment and an untreated control. Colony strength was estimated using cluster counts before and after the pollination period, and returning forager activity was quantified on two dates. Nano‑B‑Feed™‑treated colonies exhibited greater increases in cluster counts compared with untreated colonies, suggesting enhanced brood production and adult worker population growth during the pollination period. No treatment differences were detected in returning forager counts. The product was simple to apply without opening colonies, offering practical advantages for beekeepers. These preliminary findings support further replicated trials of nano‑scale feed supplements like Nano‑B‑Feed™ as a tool to improve honey bee colony performance during crop pollination.