Bumblebee colonies at risk of extinction

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

Pesticide puts bumblebee colonies at risk

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 Monday in the journal Nature Ecology & Evolution.

“Bumblebee queens that were 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.

Ontario has taken the lead in North America by placing restrictions on the use of neonicotinoids, while Europe has imposed a moratorium on their use.

Recent research by York University showed neonicotinoids had spilled over from crops such as soy and corn in Ontario and Quebec into plants and wildflowers such as maple trees, dandelions and clover.

Raine wanted to examine the effects thiamethoxam and a common parasite had on the bumblebee queen’s ability to set up a colony, a crucial part of a bee’s life cycle.

Bumblebee queens, he explained, are quite different from honeybee queens in that they largely do all of the work themselves to start a colony, from foraging to nest building to raising their young before worker bees take over.

While there has been much study of the honeybee, not as much research has been conducted on the bumblebee, Raine said.

In his lab, Raine infected half the bumblebee queens he was studying with a parasite and then placed all the bees in a cold, dark room to force an artificial hibernation. Those that survived hibernation were then split into two more groups, one of which was exposed for two weeks to pesticide-laden pollen at “field realistic” levels found in the wild, he said.

Those queen bees were placed in different nest boxes and monitored for survival and signs of egg laying.

“There was very little effect of the parasite in our experiment,” Raine said.

But he did find a substantial impact on egg laying.

“We are trying to link all this up to the broader ecology and life history of these organisms,” Raine said.

He took that new data and plugged it into mathematical models to see what would happen over time.

“We’re seeing a substantial increase of the likelihood of them not surviving over a longer period of time and that’s obviously a serious concern with the current patterns of usage of these chemicals.”

If anything, Raine said, his study is conservative, considering he only examined the effects of one pesticide and one parasite, whereas there are many other factors in the wild that play a role in the bumblebee’s health, including disease and habitat destruction.

Liam Casey , The Canadian Press

Just Posted

Our Place celebrates Christmas in July

Afternoon barbecue serves up turkey burgers and Santa hats under the hot sun

Pedestrian struck on Quadra Street

A pedestrian was struck by a vehicle on Quadra Street at Hulford… Continue reading

Police respond after dog left in vehicle at the movies

West Shore RCMP determined the animal was not in distress

Affordable housing idea dead for Central Park, idea shifts to Royal Athletic Park lot

Underground parking with housing units above to be considered for existing lot

VIDEO: Trudeau shuffles familiar faces, adds new ones to expanded cabinet

Justin Trudeau shuffles his front bench Wednesday to install the roster of ministers that will be entrusted with leading the Liberal team into next year’s election.

Wildfires erupt in B.C. Okanagan forcing evacuation orders and a highway closure

Check out a list of up-to-date information on blazes happening within the Kamloops Wildfire Centre.

‘Amazing Race Canada’ competitors face B.C. challenge

They drove Corvettes, mastered falconry basics, and ate blueberry pie in the Cowichan Valley

Grizzly bear jumps in river, chases B.C. kayaker

The bear got a bit too close for comfort along the Elaho River near Squamish

Island man convicted of 1999 sex assault at Fraser Valley music festival

James Allen Redden, formerly of Nanaimo, was found guilty of three charges

Parks Canada looks to shine light on cloudy future for historic sites

A plan is in place to produce 10-year plans designed to turn around sagging attendance figures

B.C. poet shines a bright light on struggle with homelessness

Book launch for John La Greca’s Homeless Memorial is at Vernon’s Gallery Vertigo July 21.

Former Vike returns to lead women’s rowing program

Williams rowed for UVic, Oxford and Canada

Ontario police say attack on Muslim man was motivated by hate

Two men, aged 27 and 19, have been charged with assault in the incident

Most Read