Alfred State College recently hosted a Pesticides and Pollinators symposium. Maryann Frazier, extension entomologist from Penn State, conducted a morning session that examined the role played by pesticides in the decline of North American pollinators, particularly honey bees. Dr. Gloria DeGrandi-Hoffman, research director of the USDA-ARS Honey Bee Pollination Lab in Tucson, AZ, along with Drs. Diana Sammataro, Dr. Kirk Anderson, and Dr. Mark Carroll, presented via the Internet. The researchers looked at other factors that contribute to the loss of bees, including viruses and parasites.
Of particular concern is Colony Collapse Disorder (CCD). Entomologists have long suspected a link between pesticides and the deaths of bees. While the neo-nicotinoid insecticides were found to directly kill honey bees, what was surprising was the significance of fungicides. Frazier found that of 887 samples taken of pollen, most contained multiple pesticide residues. These pesticides were often shown to have synergistic effects where the combinations are more deadly to bees that one would expect given their individual toxicity.
Because bees rely on various microorganisms to help digest their food, the use of fungicides can have a greater impact on declining bee populations. These pesticides kill the microflora in bees that enable the bees to metabolize protein from pollen. Scientific evidence presented suggests that pesticides also compromise the honey bees’ immune systems. Repeated exposure to pesticides causes cumulative effects that reduce toxic doses below what a one-time feeding would produce. Pesticides are believed to make honey bees more susceptible to stress and opportunistic infections by parasites such as the Varroa mite.
The symposium was attended by over 80 participants, most of whom are honey producers. People came from as far away as California and Michigan to attend. The Symposium was sponsored by Alfred State College and its Institute for Sustainability; The Western New York Honey Producers Association; The New York Sustainable Agriculture Working Group with USDA RMA; and Bee Culture - the Magazine of American Beekeeping.
See the Pesticide-Pollinator Workshop event page for links to view the presentations (PDFs).