A fungus that caused widespread loss of bee colonies in Europe and Asia may be playing a crucial role in the mysterious phenomenon known as Colony Collapse Disorder that is now wiping out bees across the U.S., researchers said Wednesday.
Researchers have been struggling for months without success to explain the disorder, and the new findings at the University of California, San Francisco, represent the first solid evidence pointing to a potential cause.
But the results are “highly preliminary” and are from only a few hives from Le Grand in California’s Merced County, UCSF biochemist Joe DeRisi said.
Other researchers said Wednesday that they too had found the fungus, a single-celled parasite called Nosema ceranae, in affected hives from around the country – as well as in some hives that have continued to survive and live. Those researchers also have found two other fungi and a half-dozen viruses in the dead bees.
N. ceranae is “one of many pathogens” in the bees, said entomologist Diana Cox-Foster of Pennsylvania State University. “By itself, it is probably not the culprit…but it may be one of the key players.”
Cox-Foster was one of the organizers of a meeting in Washington, D.C., on Monday and Tuesday where about 60 bee researchers gathered to discuss Colony Collapse Disorder.
“We still haven’t ruled out other factors, such as pesticides or inadequate food resources following a drought,” she said.
Beekeepers in 28 states, Canada and England have reported large losses. About a quarter of the estimated 2.4 million colonies across the U.S. have been lost since last fall, said Jerry Hayes of the Florida Department of Agriculture and Consumer Services in Gainesville.
Besides honey production, commercial beehives are used to pollinate one-third of the country’s agricultural crops, including apples, peaches, pears, nectarines, cherries, strawberries and pumpkins. Ninety percent of California’s almond crop is dependent on bees, and a loss of commercial hives could be devastating.
