Quirks and Quarks

Pesticides Prevent Proper Pollination

Bumblebees dosed with neonicotinoid pesticides at the levels they would encounter in nature pollinate apple trees less well, and cause the trees to produce inferior fruit.

Neonicotinoid pesticides cause bumblebees to pollinate less effectively.

Bumblebee on an apple flower (Victoria Wickens/University of Reading)
Neonicotinoid pesticides are a widely used and effective way to prevent damage to important crops, but there are significant concerns about their impact on non-pest insects, especially pollinators like bees.

Research has already revealed that sub-lethal doses of these pesticides can affect bee behaviour, including reproduction. Now, new work by Dr.Nigel Raine from the School of Environmental Sciences at the University of Guelph, and his colleagues, has shown that bees who consume these chemicals are less effective pollinators.

In their study, they gave bumble-bees the kind of doses they might encounter in nature, and observed how well they pollinated apple trees. The bees were less efficient pollinators and the fruit production of the trees suffered as a result. This raises new concerns about how pesticides' impact on pollinators might affect both agricultural crop and wild plant productivity.

Related Links

- Paper in Nature
- University of Guelph release
- CBC News story
The Atlantic story
The Guardian story
Quirks feature: The Birds and the Bees - and the Pesticides
- Quirks story: Bees Get a Buzz from Pesticides