Bumblebee colonies at risk of extinction after pesticide exposure, study says

A widely used pesticide is placing bumblebee populations at an increased risk of extinction, a new study from an Ontario researcher suggests.

Nigel Raine, an environmental science professor at the University of Guelph, discovered that thiamethoxam, a major neonicotinoid found in agricultural crops throughout the world, reduced the chances of bumblebee queens starting new colonies by more than a quarter.

The results were published in the journal Nature Ecology & Evolution.

“Bumblebee queens that were

Bees are crucial to agriculture.

exposed to the pesticide were 26 per cent less likely to lay eggs to start a colony,” Raine said of the research conducted in his lab with researchers from Royal Holloway, University of London.

“It was a bigger impact than I was expecting. And our modelling suggests it could have a major impact on population persistence and increases the chances a population could go extinct.”

Bees are crucial to agriculture. Published reports suggest about a third of the crops eaten by humans depend on insect pollination, with bees responsible for about 80 per cent of that figure.

But bee populations are declining worldwide as scientists try to figure out why.

Research has suggested the use of neonicotinoids is among the factors contributing to the declines.