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Think bees are not important? Think again.
Don Coxe has alluded several times to the mystery of the disappearing bees, a problem which may have devastating effects on agriculture worldwide.
Two studies to be published in this month's Science journal., one by UK researchers and one in French researchers, suggest that neonicotinoid insecticides, could be the culprits and harm bee populations worldwide. These have been in use since the early 1990s.
Scientists have in the past proposed that pesticides could be partially to blame for the disappearing bees, but it's been unclear exactly how. In the last few years, much time has been devoted to the mysterious disappearance of bees, referred to as Colony Collapse Disorder. Honeybee populations have been decimated and bumblebee species have also gone missing.
In the US, the Environmental Protection Agency says on its website that France, Germany, Italy and Slovenia have all instituted bans on neonicotinoids over fears of their effect on bees, but says that "to the EPA's knowledge, none of the incidents that led to suspensions have been associated with Colony Collapse Disorder".
Not so says Dave Goulson of the University of Stirling, co-author on the British study: “Some bumblebee species have declined hugely. For example in North America, several bumblebee species which used to be common have more or less disappeared from the entire continent. In the U.K., three species have gone extinct,”
Dr. Goulson and his colleagues exposed developing bumblebee colonies to a neonicotinoid called imidacloprid at doses comparable to what they might find in the wild. These colonies were around 10% smaller than those that weren't exposed. They also produced 85% fewer queen bees (which means far fewer bee-leaders that can set up new colonies).
“Bumblebees pollinate many of our crops and wild flowers. The use of neonicotinoid pesticides on flowering crops clearly poses a threat to their health, and urgently needs to be re-evaluated,”
Lost. The French study stuck tiny RFID chips on to honeybees so they could track them as they buzzed in and out of their hives. The French National Institute for Agricultural Research (INRA) found that bees they had blasted with a sublethal dose of the neonicotinoid thiamethoxam got disorientated and couldn't find their way home.
Honeybees have a homing ability that lets them navigate back to their hives, which the researchers think was messed up by the pesticide. The lost honeybees were two to three times more likely to die outside the nest, pushing populations down to levels that would be difficult to recover from.
Says study author Mikaël Henry of INRA: "Our study raises important issues regarding pesticide authorization procedures. So far, they mostly require manufacturers to ensure that doses encountered on the field do not kill bees, but they basically ignore the consequences of doses that do not kill them but may cause behavioral difficulties," Read More
