Insecticide's effect on bees

MONTREAL, Quebec -- Seeding is over for this year on Canadian corn and soy farms. But a student's research suggests the consequences on bees could last a long time.

MONTREAL, Quebec -- Seeding is over for this year on Canadian corn and soy farms. But a student's research suggests the consequences on bees could last a long time.

He has collected data that showed apiaries installed less than three kilometers (1.86 miles) from insecticide-treated fields had rate of mortality three times higher.

Human beings should take note. Pollination is responsible for 70 percent of cultivated plants, and for 35 percent of humans' overall food consumption. Fewer bees means fewer plants -- notably apples, strawberries, cucumbers -- and could ultimately mean a drop in the food supply.

The Quebec master's student, Olivier Samson-Robert, had attempted to put a figure on the noted decline in bee populations and detemine how much of it was linked to a certain type of insecticide.

The Laval University student released the first part of his study about bees' mortality around fields treated with neonicotinoid insecticides, one of the most widely used insecticides in the world.


"The neonicotinoid insecticide causes a higher mortality rate," Samson-Robert says.

Neonicotinoid insecticides have been allowed in Canada since 2004.

They are chemically similar to nicotine, which has a long tradition in agriculture. Tobacco has been used as an insecticide since at least the 15th century, according to the U.S. Environmental Protection Agency.

Samson-Robert says insecticide is ubiquitous, with 99 percent of corn seeds and 50 percent of soy seeds in Quebec coated with it, over a land mass that covers 500,000 hectares (1.24 million acres) of the province.

Particles from that insecticide escape into the air when the seeds are planted, Samson-Robert says. He argues that using a funneling device to steer the seeds straighter into the ground when seeding would help reduce contamination.

He says particles from insecticides fall onto bees, or onto the flowers that bees are visiting. Particles also are present in the water bees drink, he says.

According to Jean-Pierre Chapleau, spokesman for the Quebec Beekeepers' Federation, beekeepers want neonicotinoid insecticides banned.

Chapleau says beekeepers don't blame farmers, because they can't buy seeds that have not been treated with insecticides even if they want to.



The industry says that's not accurate.

Gilles Corno is regional director for Pride Seeds. He says it's possible to buy corn seeds in Canada that are not treated with neonicotinoids, if ordered at a certain time of the year.

He says Samson-Robert's findings are more anecdotal than scientific -- "observations and not a study."

Samson-Robert based his work on the observation of 12 apiaries in Monteregie and Estrie regions, every two days during seeding time from the beginning of May to mid-June.

Proving the effect of insecticides isn't so simple.

Chapleau says that, even if the contamination is real, it's not easy to spot in real-time.

Swarms of bees aren't dying suddenly, but over time, he says, and they have more health issues that lead to increased mortality rates.


"Beekeepers don't report problems because they don't see anything that prompts them to take a picture or to collect samples," Chapleau says.

"It's a chronic issue. We can't see it directly."

For him, neonicotinoid insecticides are not the only cause of bees' mortality.

He says varroa mites kill more bees than pesticides.

But pesticides do cause economic damage, Chapleau says.

He says they make apiaries less efficient -- with bees losing their olfactory memory and sense of direction. In the past 10 years, in Quebec, the apiary's honey productivity has decreased 30 percent, he says.

"It's not because we can't precisely assess the damages and it's not because there is no acute intoxication that there are no problems," Chapleau says. "A 5 percent or a 10 percent decrease of production is serious for beekeepers.

"That situation didn't exist before neonicotinoid insecticides were introduced."


Some researchers wonder whether neonicotinoids provide any benefit.

Several studies suggest the quantity of insect pests in the North American soil doesn't justify the use of neonicotinoid insecticides.

The Government of Canada has no current plan to ban neonicotinoids.

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