Impact of controlled neonicotinoid exposure on bumblebees in a realistic field setting

This field study found that after a five week exposure to field realistic levels of clothianidin (5 ppb) bumble bee colonies had fewer adult workers, drones and gynes compared to untreated colonies.  The researchers did not find a difference in colony mass between the treated and untreated colonies.  By measuring foraging and pollen collection through multiple methods, the researchers were also able to identify subtle changes to the pattern of foraging activity.