A new pesticide believed to be a successor to the banned neonicotinoids has resulted in total death among mason bees in a recent evaluation.
The pesticide in question, flupyradifurone, is considered to be less hazardous to pollinators and has therefore received global approval for application on crops that attract bees.
However, researchers from the University of Bristol and the University of Texas at Austin found, to their surprise, that the chemical was deadly to the bees known as Osmia lignaria when they were exposed to wildflowers treated with the pesticide.
Additionally, they observed several sublethal effects. Seven days after the application, bees released into areas with pesticide-treated plants showed reduced nesting behaviors, lower survival rates, and were less effective foragers, taking an average of 12.78% longer to gather pollen and nectar compared to control bees.
Harry Siviter, the lead author from Bristol’s School of Biological Sciences, stated: “These findings indicate that exposure to flupyradifurone presents a serious threat to vital pollinators and can negatively affect wild bee populations at concentrations realistic for field use.”
Bees play a crucial role in pollinating both crops and wild plants. Neonicotinoid pesticides have adversely affected pollinators, resulting in significant restrictions on their usage in the EU and other areas, thus increasing the quest for ‘novel’ insecticides.
Harry emphasized that “there is a pressing need to assess alternative crop treatments due to limitations in formal ecotoxicology evaluations.”
“These findings serve as a warning against replacing neonicotinoids directly with new insecticides.
“Our research contributes to an increasing array of evidence indicating that current pesticide risk assessments do not adequately safeguard wild bees from the harmful effects of pesticide usage.”
To prevent ongoing cycles of introducing and retracting novel pesticides—which adversely affects the environment—the researchers assert that a comprehensive collection of evidence should be analyzed before creating policies and regulations.
Harry suggested, “It would be prudent to restrict the application of commercial pesticides containing flupyradifurone to non-flowering crops while further studies are undertaken.”
“In the long run, as is already being witnessed in the EU, there is a need to adopt a more comprehensive risk assessment approach that takes into account the biology of non-Apis bees to enhance the protection of pollinators from the unintended negative effects of pesticides.”
The research team plans to expand their study to evaluate the effects of soil exposure on solitary bees.
