In a letter dated Monday and sent to U.S. Department of Agriculture head Tom Vilsack and Environmental Protection Agency chief Gina McCarthy, the scientists write that documented bee declines "are not sustainable," and stress that the pollinators play a crucial role "in our agricultural system and economies."
Beekeepers in the nation have been hit with average losses of nearly 30 percent for the past eight years, they write to Vilsack and McCarthy, who lead the months-old Pollinator Health Task Force.
Protecting the pollinators, they write, means listening to a body of scientific evidence that links a class of pesticides called neonicotinoids, or neonics, with lethal and sub-lethal harm to bees.
Neonics are persistent and systemic, the experts write, creating multiple paths of exposure, including from dust, pollen, or water droplets from treated plants, for bees to the pesticides.
The letter references a global analysis based on 800 peer-reviewed reports called the Worldwide Integrated Assessment of the Impact of Systemic Pesticides on Biodiversity and Ecosystems (WIA), which focused on neonics and found "clear evidence" that they posed threats to bees. In addition to studies linking neonics to harm to bees, the scientists note in the letter, research has also pointed to questionable efficacy of neonics on crop yields and production.
"The President’s Task Force should listen to the body of science that links pesticides to bee harm and bee declines," stated letter signatory Jim Frazier, PhD, an emeritus entomology professor at Pennsylvania State University and commercial beekeeper advisor who specializes in chemical ecology.
"These systemic pesticides are not only lethal to pollinators, but at low doses can disrupt critical brain functions and reduce their immunity—leaving them susceptible to common pathogens. The weight of the scientific evidence certainly incriminates neonicotinoids," he added.
Based on the threats neonics pose, the letter outlines three recommendations the scientists say the task force should prioritize: placing a moratorium on use of neonics; suspending registrations on neonics until the EPA completes its review, which won't happen before 2018; and increasing investment into looking for non-pesticide alternatives to neonics.
Further, the letter states,
the White House Task Force should recommend incentives for farmers to create healthy pollinator habitats in the form of diversified, pesticide-free landscapes as an alternative to our current system of intensive monoculture. Such landscapes support natural enemies also, and thus provide an alternative to pesticides. Maintaining high-quality habitats around farms aids in promoting pollinator richness and diversity. Thriving populations of beneficial insects result in a healthier and more resilient crop as well as benefiting the larger ecosystem.
The scientists' letter was timed to meet the deadline the Pollinator Health Task Force set for public comments following two "public listening sessions" this month.