Bumblebees, Impact of Pesticides

University of Guelph

Pesticides affect bees' ability to locate flowers, drink nectar - Bumblebees exposed to even low levels of pesticides have trouble acquiring the pollination skills necessary to retrieve nectar from some wildflowers -- especially those with complex shapes.

Researchers found bumblebees exposed to to neonicotinoid insecticide took longer to collect pollen and sought pollen from different flowers than control bees.

"Bees rely on learning to locate flowers, track their profitability and work-out how best to efficiently extract nectar and pollen," senior study author Nigel Raine, the Rebanks Family Chair in Pollinator Conservation at the University of Guelph, said in a press release. "If exposure to low levels of pesticide affects their ability to learn, bees may struggle to collect food and impair the essential pollination services they provide to both crops and wild plants."

Previous studies have shown neonicotinoid pesticides can affect memory and learning abilities in honeybees.

In the experiments, pesticide-contaminated bumblebees actually collected more pollen than the control group. Researchers believe the control group bees split their time more evenly between collecting pollen and learning how to retrieve pollen from more complex flower shapes.

If pesticides limit bumblebees' ability to learn about and adapt to the natural world, wild bees could become increasingly vulnerable to environmental change.

"Our results suggest that current levels of pesticide-exposure could be significantly affecting how bees are interacting with wild-plants, and impairing the crucial pollination services they provide that support healthy ecosystem function," Raine said.