Pesticides damage the brains of bees
A mysterious malady that has been killing honeybees en masse for several years appears to have expanded drastically in the last year, commercial beekeepers say, wiping out 40 percent or even 50 percent of the hives needed to pollinate many of the nation’s fruits and vegetables.
A conclusive explanation so far has escaped scientists studying the ailment, colony collapse disorder, since it first surfaced around 2005. But beekeepers and some researchers say there is growing evidence that a powerful new class of pesticides known as neonicotinoids, incorporated into the plants themselves, could be an important factor.
The pesticide industry disputes that. But its representatives also say they are open to further studies to clarify what, if anything, is happening.
“They looked so healthy last spring,” said Bill Dahle, 50, who owns Big Sky Honey in Fairview, Mont. “We were so proud of them. Then, about the first of September, they started to fall on their face, to die like crazy. We’ve been doing this 30 years, and we’ve never experienced this kind of loss before.”
In a show of concern, the Environmental Protection Agency recently sent its acting assistant administrator for chemical safety and two top chemical experts here, to the San Joaquin Valley of California, for discussions.
In the valley, where 1.6 million hives of bees just finished pollinating an endless expanse of almond groves, commercial beekeepers who only recently were losing a third of their bees to the disorder say the past year has brought far greater losses.
The Newcastle University study found that one in five bees exposed to imidacloprid from the neonicotinoid family of pesticides, that is commonly used on UK crops including oilseed rape, were “unable to learn”.
This means the whole colony is affected because the bees rely on memory to find flowers and bring back nectar to the hive, said the researchers.
The study, published in Nature Communications, comes amid mounting pressure on the UK Government to make a decision on whether neonicotinoids should be banned, as environmentalists fear the pesticides are causing a decline in pollinators.
But it was not published in a journal and was dismissed by some scientists as “flawed”.
The Newcastle University study found 18.5 per cent of bees exposed to imidacloprid over four days lost the ability to learn.
Some 30 per cent of bees also exposed to another chemical coumaphos, that is used by beekeepers to treat disease, performed poorly in memory tests.
Dr Geraldine Wright, a biologist at Newcastle University, said the study suggests bees in the wider environment are being affected by neonicotinoids.
“If bees are exposed to these neonicotinoids their ability to learn and remember is impaired. If they cannot do that they cannot feed and the whole colony suffers,” she said.
The University of Dundee, that also looked at the results, concluded for the first time that neonicotinoids have a direct impact on the actual physiology of bees’ brains.
However the Prof Francis Ratnieks, Professor of Apiculture at the University of Sussex, said the lab-based study used higher doses of neonicotinoids than would be found on oilseed rape.
“It’s no surprise that insecticides at high concentrations are harmful, but we don’t know whether the low levels of neonicotinoid insecticides in the nectar and pollen of treated plants, such as oil seed rape, are harmful in the real world.”
i mean really..do we even have to argue this?..of course its the pesticides..its fucking poison!
its not natural..so things dont work correctly..and its not climate change either!