Bees in decline due to common pesticides

Commonly used pesticides may be linked to declining numbers of bumble and honey bees, says two new European studies published Thursday.

Both studies, one British, the other French, found that neonicotinoid insecticides, often used on corn crops, not only killed pests but also spread to the nectar and pollen of flowering crops causing fatal harm to bees.

One study found that bumble bee colonies given doses of imidacloprid, a common insecticide used on crops since the 1990s, produced about 85 percent less queen bees than unexposed colonies, according to Bloomberg.

In the other study, according to AFP, French scientists glued tiny radio transmitters to the bees in order to track them when they left the hive.

Researchers found that those bees exposed to neonicotinoids were two to three times more likely not to return.

Read more on GlobalPost: Promiscuous queens have healthier hives

One explanation is that the bees lose their homing senses and are unable to find their way home.

In recent years scientists have been searching for explanations about massive declines in bee colonies.

"Where'd they go? We have no clue about that actually," said study author Mickael Henry, a bee ecologist for the French national agriculture institute, reported the Associated Press.

The scientist involved in both studies warned of the use of these pesticides before more research was done.

“I personally would like to see them not being used until more research has been done,” said David Goulson, an author of the bumblebee paper who teaches at the University of Stirling, in Scotland, reported the New York Times. “If it confirms what we’ve found, then they certainly shouldn’t be used when they’re going to be fed on by bees.”

The companies that produced the pesticides defended their use, stating that the studies used far too high levels of pesticides, reported the Associated Press.

The two studies were published in the journal Science.

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