In addition, the new study indicates that "the clothianidin-type neocotinoid pesticide (Bayer) also has the same negative effect." The Harvard team mentioned other studies that indicate that exposure to pesticides reduces the resistance of bees to parasites or mites, leading to the massive collapse of hives. In the new study they found the same amount of pathogens in both bees with and without a pesticide environment.
"We have demonstrated again in this study that neonicotinoids are highly responsible for triggering CCD Hive Collapse Disorder in bee hives that were healthy before the onset of winter," said lead author Chensheng (Alex) Lu , associate professor of environmental exposure biology at Harvard School of Public Health.
The scientists conclude that the cases of massive hive collapses detected from 2006 onwards were caused by pesticides, specifically neocotinoids.
Instead, to date, some studies have named other possible causes, such as pathogen infestation and beekeeping practices.
In field research in Australia's New England, in 2013 six out of 12 hives treated with pesticides were lost. In turn, only one was lost by an intestinal parasite called Nosema.
In the current study, bees with pesticides had a death rate of 50 percent. Instead in 2012, it was 95 percent. This also happened in the winter 2010-2011 at Masachssetts.
Manufacturers of neocotinoid chemicals and pesticides such as Bayer AG (BAYN), Syngenta AG (SYNN) and Dow Chemical Co. (DOW USA) are trying to avoid a congressional ban on their products, reported May 14. the Booberg media, arguing that the elimination of the products will do little to help bees, farmers and gardeners and will reinforce that they use products that are more harmful.
Dead bees are responsible for increased crop losses, which is why the US Department of Agriculture launched an annual survey of bee losses in May 2014.
Surveys reported by the Center for Disease Control show that a third of bees in an estimated 2.6 million colonies fail to survive the winter dormancy period.