Precocious foraging in honey bees due to pesticide stress

Commercial honey bee colonies have experienced rapid declines in the past two decades due to a synergy of stressors, such as pesticides and poor forage. Stress can have lasting physiological changes in worker bees, such as the accelerated depletion of internal nutrient stores. Experimental reductions in abdominal lipid have been linked to a behavior known as precocious foraging, wherein worker bees forage earlier in their adult lifespan. Precocious foragers have been speculated to be less effective, but the relationship between precocious foraging and reduced pollination services requires further investigation. In this study, we have found that pyriproxyfen, an insect growth regulator, negatively influences foraging behavior via the depletion of fat reserves. Additionally, bees treated with pesticide return with lower pollen yields than their unstressed cohort. These results demonstrate a potential link between ubiquitous agricultural stressors and reduced pollination services.