AAAS / Science
A bee with a transmitter glued to its back was one of the specimens in a study that used the radio technology to track what happened to bee colonies exposed to a widely used pesticide.
By Miguel Llanos, msnbc.com
A widely used crop pesticide first introduced in the 1990s has caused significant changes to bee colonies worldwide and removing it could be the key factor in restoring nature's army of pollinators, according to two studies released Thursday.
The scientists behind the studies called for regulators to consider banning the class of?chemicals known as neonicotinoid insecticides. In the U.S., the Environmental Protection Agency told msnbc.com that the studies would be incorporated into a review that's currently underway.
"Our study raises important issues regarding pesticide authorization procedures,"?stated Mikael Henry, co-author of a study on?honey bees. "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."
"There is an urgent need to develop alternatives to the widespread use of neonicotinoid pesticides on flowering crops wherever possible," added the authors of the second study on bumble bees.
The studies are the first?to go outside the lab and into the fields, where the experts said they?detected how the pesticide impacts bees as they collect pollen and pollinate flowers and crops.
Honey bee populations have been crashing around the world in recent years, and pesticides have been suspected, along with other potential factors such as parasites, disease?and habitat loss, in what's known as Colony Collapse Disorder. In the U.S., some beekeepers in 2006 began reporting losses of 30-90 percent of their hives, according to the U.S. Department of Agriculture.
Combating Colony Collapse Disorder is hardly an esoteric exercise. The USDA notes that "bee pollination is responsible for $15 billion in added crop value, particularly for specialty crops such as almonds and other nuts, berries, fruits, and vegetables.
"About one mouthful in three in the diet directly or indirectly benefits from honey bee pollination," it adds.
Published in the peer-reviewed journal Science, one study by?British scientists?looked at honey bees and the other by French scientists examined bumble bees, which unlike honey bees live in the wild but also are key pollinators.
In the?bumble bee study, researchers concluded that?colonies treated with?nonlethal levels of?the pesticide "had a significantly reduced growth rate and suffered an 85% reduction in production of new queens" compared to colonies without the pesticide.
"It was quite?massive,"?researcher Penelope Whitehorn said of the reduction?at a press conference Thursday.?(Click here for audio of the news conference.)
"Bumble bees have an annual life cycle and it is only new queens that survive the winter to found colonies in the spring," the authors noted. "Our results suggest that trace levels of neonicotinoid pesticides can have strong negative consequence for queen production by bumble bee colonies under realistic field conditions, and this is likely to have a substantial population-level impact."
In the honey bee study, radio transmitters were attached to the back of?bees?to see how they foraged in conditions with and without the pesticide.
The pesticide, the researchers concluded, impaired the homing ability of bees and exposed bees were two to three times more likely to die while away from the hive. That?"high mortality ...?could put a colony at risk of collapse" within a few weeks of exposure, especially in combination with other stressors,?they noted.
"We were actually quite surprised by the magnitude," Henry told reporters.
The EPA, contacted by msnbc.com, provided a statement saying that it has "begun reviewing the two studies ... and they will be considered as part of registration review." Non-EPA scientists will weigh in at a special meeting in the fall, it added.
The prevailing view among most scientists and regulators is that?"complex interactions among multiple stressors" are?to blame, the EPA stated.? "While our understanding of the potential role of pesticides in pollinator health declines is still progressing, we continue to seek to learn what regulatory changes, if any, may be effective."
The American Chemistry Council, which represents the chemical industry, told msnbc.com it would comment on the studies once its experts had reviewed them.
More content from msnbc.com and NBC News:
Follow US News on msnbc.com on Twitter and Facebook
san francisco earthquake terminator salvation terminator salvation jarhead montrose ronnie montrose marshawn lynch
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.