Methods for determining the effect of pesticide exposure on bees

Category : 2014
Tags : bees, pesticides, entomology

December 3, 2014

Dr. Reed Johnson, Ohio State University

Reed Johnson

Reed M. Johnson, PhD is an Assistant Professor in the Department of Entomology at The Ohio State University – Ohio Agricultural Research and Development Center (OARDC) in Wooster, Ohio. Dr. Johnson received a B.A. from Wabash College, a M.S. from Wake Forest University and a Ph.D. in Entomology from the University of Illinois at Urbana-Champaign. His research focuses on determining how bees are exposed to pesticides and what effect exposure to pesticides has on the health of honey bees and other pollinators. He has published over 20 peer-reviewed papers on bees and bee health. He teaches courses in pesticide science and beekeeping at Ohio State.

In the 1960’s and 1970’s, as many new pesticide chemistries were being developed, the acute hazard to adult bees could be predicted and incorporated into pesticide label guidelines. While the LD50 continues to be a useful measure of pesticide toxicity to individual adult bees, there has been a growing realization that decisions based on this statistic alone do not consider the effects that exposure to a pesticide may have on the hive as a whole. Some pesticides may have a greater effect on immature bees than on adults. Pesticides may have different effects on the reproductive castes in a bee colony – the queen and drones – and the colony’s long-term ability to grow. Pesticide exposure may affect the performance of bees in a way that is not acutely lethal, but which may reduce a bees’ lifespan, affect its ability to do useful work, or increase its susceptibility to pests and pathogens. It might seem obvious that the simplest approach to all of these new questions would be to perform field tests of pesticides on whole bee colonies, but the complexities of bee biology and the challenges of beekeeping conspire to make field tests far from simple.

Bookmark the permalink.