However, Pettis and others said while the parasite nosema ceranae may be a factor, it cannot be the sole cause. The fungus has been seen before, sometimes in colonies that were healthy.
Recently, scientists have begun to wonder if mankind is too dependent on honeybees. The scientific warning signs came in two reports last October.
First, the National Academy of Sciences said pollinators, especially America's honeybee, were under threat of collapse because of a variety of factors. Captive colonies in the United States shrank from 5.9 million in 1947 to 2.4 million in 2005.
Then, scientists finished mapping the honeybee genome and found that the insect did not have the normal complement of genes that take poisons out of their systems or many immune-disease-fighting genes. A fruitfly or a mosquito has twice the number of genes to fight toxins, University of Illinois entomologist May Berenbaum.
What the genome mapping revealed was "that honeybees may be peculiarly vulnerable to disease and toxins," Berenbaum said.
University of Montana bee expert Jerry Bromenshenk has surveyed more than 500 beekeepers and found that 38 percent of them had losses of 75 percent or more. A few weeks back, Bromenshenk was visiting California beekeepers and saw a hive that was thriving. Two days later, it had completely collapsed.
Yet Bromenshenk said, "I'm not ready to panic yet." He said he doesn't think a food crisis is looming.
Even though experts this year gave what's happening a new name and think this is a new type of die-off, it may have happened before.
Bromenshenk said cited die-offs in the 1960s and 1970s that sound somewhat the same. There were reports of something like this in the United States in spots in 2004, Pettis said. And Germany had something similar in 2004, said Peter Neumann, co-chairman of a 17-country European research group studying the problem.
"The problem is that everyone wants a simple answer," Pettis said. "And it may not be a simple answer."
