From IPM in the South
By Rosemary Hallberg
A study in Europe that tested bee health in neonicotinoid treated fields had different results in two countries, supporting previous statements that bee declines are the result of multiple factors.
The study, which was the largest field study ever conducted on bees and neonics, was featured in Science this past week. Scientists monitored bees in 33 locations in the United Kingdom, Germany and Hungary. Bees in each location were in canola fields, some of which had been treated with neonics and fungicides and others that were treated only with fungicides.
At the locations in Hungary and the United Kingdom, bees in the neonic-treated canola fields had more difficulty reproducing and surviving the winter. In Germany, however, bee colonies prospered no matter whether they were in the treated or untreated fields. In fact, honey bee colonies near the neonic-treated fields actually reproduced more than those in the fungicide treated fields.
Richard Pywell, the scientist from the Centre for Ecology & Hydrology who led the study, said that the environment may play a large part in bee health.
“We believe that other factors interact with neonicotinoid exposure to cause negative effects on honey bees and wild bees,” he told National Public Radio.
In Germany, bees had more flowers to choose from than just canola. In addition, the bees had fewer parasites than bees in the other countries.
A separate study in Canada found that bees exposed to neonics tended not to keep their hives clean and lost queens more often than unexposed bees.
Scientists say that the results of both studies point to multiple factors in the decline of bees.
“We shouldn’t just focus on insecticides,” Nigel Raine, a bee specialist at the University of Guelph, told NPR. “They’re part of the problem, but if we focus on that and then just say, ‘OK, we understand that now; the problem’s fixed,’ I don’t think that’s right. We need to be clear about how we’re managing the landscapes, both agricultural and urban and more natural landscapes, to support healthy biodiversity of pollinators.”