Transportation sensitizes honey bees to insecticides
Zachary Y. Huang, Shudong Luo
Department of Entomology, Michigan State University, USA; Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing, China
Honey bees are critical pollinators whose managed populations face global declines due, in part, to an increased use of insecticides. Transportation of honey bees is necessary all over the world to meet the demands of fruit and vegetable pollination. We hypothesize that transportation weakens honey bees such that they are more prone to insecticide poisoning. We show that transportation and mock transportation both sensitize honey bees to neonicotinoid insecticides. We then tested whether this is because transportation makes bees age faster and that older bees are more sensitive to insecticides. Indeed, significantly higher juvenile hormone titers were found in mock transported bees than that in control bees. We also show that foragers are more sensitive to insecticides than newly emerged bees and nurses. These results suggest the mechanisms of sensitization are due to transportation making bees age faster and aged bees being more vulnerable to insecticides. Thus the widely-practiced transportation of honey bee colonies sensitizes them to insecticides, increasing their risk of pesticide poisoning. Further studies are needed to provide measures to counter these effects.