Over the past three decades, bee researchers in the United States have struggled to understand the complex interactions and diagnosis of multiple co-occurring disorders of honey bees. Among scientists, the overall consensus is that there are a variety of underlying factors that affect the health of honey bees including parasites, nutrition deficiencies, diseases, weather, beekeeping practices, pesticides, genetic weakness and queen issues.
Recently published scientific studies have received significant attention, because they raised concerns about a possible connection between the use of neonicotinoids and bee colony health. However, comprehensive reviews of studies and databases comprising 15 years of research have been published by a diverse group of researchers and directly challenge claims against neonicotinoids as a significant cause of colony decline.
Two recent examples authoritatively challenge unsubstantiated claims against neonicotinoids as a cause of honeybee decline. In its recent 92-page report, the Australian Pesticides and Veterinary Medicines Authority examined the impact of that country’s extensive use of neonicotinoids, concluding, “the introduction of the neonicotinoids has led to an overall reduction in the risks to the agricultural environment from the application of insecticides,” and noted, “Australian honeybee populations are not in decline, despite the increased use of this group of insecticides in agriculture and horticulture since the mid-1990s.” A review by Fairbrother et al. (2014) criticized the overreliance of laboratory studies in evaluating risk, noting, “Assessing risks only under worst-case conditions with individual honeybees, divorced from properties provided by colony interactions, serves only to understand potential mechanisms of action of different chemicals but not their actual risks.” When considering the extensive body of existing research, the authors concluded that “it is not reasonable, therefore, to conclude that crop-applied pesticides in general, or neonicotinoids in particular, are a major risk factor for honeybee colonies.”
|The Environmental Protection Agency (EPA) is “not aware of any data indicating that honey bee declines...in the U.S. is correlated with the use of pesticides in general or with the use of neonicotinoids in particular.” (EPA petition response memo, 07/17/12)
It is important to note that laboratory studies that imply a connection between the use of neonicotinoids and colony decline focus on the response of individual bees to different pesticide application rates – including deliberate overexposure. Such research is useful for product evaluation, but results do not imply that they are transferable to “real world” field exposure conditions. Thus, care must be taken to draw the right conclusions from the findings of laboratory studies.
Neonicotinoid insecticides represent an important advancement in agricultural technology that has helped American farmers increase productivity and improve cost competitiveness. These products provide clear performance and environmental advantages over the older chemistries they replaced. The crop protection industry strongly endorses ongoing research and meaningful stewardship measures, including the adoption of best management practices, to protect honey bees and ensure colony health.