Relationship of Landscape Type on Neonicotinoid Insecticide Exposure Risks to Honey Bee Colonies: A Statewide Survey

Area of Science:

• Agricultural Science
• Environmental Science
• Entomology

Background:

• Neonicotinoid insecticide use is a suspected driver of honey bee colony decline.
• Previous studies reported low detection rates of neonicotinoids in field-collected honey bees.

Purpose of the Study:

• To assess honey bee colony exposure to neonicotinoid insecticides.
• To determine if landscape type or county pesticide use predicts neonicotinoid exposure in honey bees.

Main Methods:

• Collected honey bee, beebread, and pollen samples from apiaries in Virginia over two years.
• Analyzed samples for neonicotinoid insecticide residues, specifically imidacloprid.
• Correlated detections with landscape characteristics and county-level pesticide use data.

Main Results:

• Trace concentrations of imidacloprid were detected in honey bees (3.97 ng/g), beebread (11.5 ng/g), and pollen (12.6 ng/g).
• Imidacloprid was only detected in July and August samples.
• Landscape type and county pesticide use did not predict neonicotinoid detections in honey bees or beebread.

Conclusions:

• Field surveys may underestimate honey bee exposure to neonicotinoids due to low detection rates.
• Undetected or low-level exposures raise concerns about potential threats to honey bee health and other pollinators.
• Further research is needed to accurately assess pollinator exposure risks.