http://www.bloomberg.com/apps/news?pid=20601124&sid=aTRSdWWGdLOE&refer=home Bee Disease Spread From Commercial Hives, Study Finds By Alan Bjerga July 23 (Bloomberg) -- Wild bumblebees are probably contracting a disorienting and often fatal disease from their commercial cousins, contributing to the decline of pollinators in North America, a Canadian study concludes. Managed bumblebees, which pollinate crops worth about $19 billion worldwide, are introducing illnesses that have ravaged wild populations of the same species, according to the study, which is being published online today in the science journal PLoS One. Feral bee losses also harm commercial hives, which are built partly by collecting from the wild. Bumblebees are the second-biggest pollinating insect in the U.S. after honeybees, which are threatened by Colony Collapse Disorder, a separate ailment marked by the sudden, massive disappearance of bees that occurred in at least 35 states and three continents last year. The study's findings point to a need for commercial beehives of all species to be managed more effectively, said co-author Michael Otterstatter of the University of Toronto. ``Improved management of domestic bees is seemingly exactly what is needed -- greater attention to the types of parasites they have,'' said Otterstatter, who conducted his research with University of Toronto colleague James Thomson. Potentially `Devastating' ``Pathogen spillover, whether it's in bumblebees or in something like Colony Collapse Disorder, has the potential to be just devastating for the wild bee communities.'' In the study, the researchers examined bees at four Ontario sites near commercial greenhouses to see whether a parasite common in managed bumblebees was unusually prevalent in the wild population. The parasite robs bees of their ability to distinguish between flowers that contain nectar and those that don't, Otterstatter said. For commercial bees fed by their owners, that skill isn't important. For wild bees, its absence is deadly. ``Infected bees make an incredible number of mistakes,'' Otterstatter said. ``They visit empty flowers again and again'' as they slowly starve to death, he said. The study found that up to half the wild bees near greenhouses were infected with the pathogen, while no bees were infected far from greenhouses. The research model predicts that, over time, diseases transmitted from commercial bees will lead to widespread epidemics among wild bees. Pollination The finding is important because wild bees play a major role in pollinating crops ranging from apples to zucchini, Otterstatter said. And because it's nearly impossible to keep commercial bees of any species from mingling with feral cousins because of how they're used -- greenhouses have vents, and honeybees are released in open fields -- proper care and feeding of commercial beehives is essential, he said. Otterstatter said he hopes his study on bumblebees will spur similar inquiries on the disease relationship between wild and commercial honeybees. Scientists have gained little understanding about why more than a third of U.S. honeybees died during the past two winters, a phenomenon that may affect crop pollination next year, experts told a congressional committee last month. U.S. Research The University of Georgia received $4.1 million July 17 from the U.S. Department of Agriculture to search for the cause of Colony Collapse Disorder and find ways to improve bee health. ``Bees are an extremely valuable contributor to the overall productivity of American agriculture, but invasive pests, diseases and environmental stresses are putting U.S. bees at serious risk,'' Agriculture Secretary Ed Schafer said in a statement announcing the grant. The University of Toronto bumblebee study was funded by the Natural Sciences and Engineering Research Council of Canada and Ontario Graduate Scholarships. Nationally, the commercial honeybee population dropped more than 36 percent this year, according to a survey by the Apiary Inspectors of America. Commercial bees, which do most of the pollinating for a third of U.S. crops, have declined during the past two decades to about 2.3 million honey-producing colonies from about 3.5 million. Commercial bees add $15 billion annually in value to U.S. crops, according to the Agriculture Department. Pesticides, mites and viruses are the leading suspects behind colony collapse. Wild bees have a tougher time surviving than commercial bees, which are closely monitored, Pennsylvania State University beekeeper Maryann Frazier said last month. To contact the reporter on this story: Alan Bjerga in Washington at [log in to unmask] Last Updated: July 23, 2008 11:56 EDT **************************************************** * General Information About BEE-L is available at: * * http://www.honeybeeworld.com/bee-l/default.htm * ****************************************************