By Jon Hurdle PHILADELPHIA, Feb 12 (Reuters) - A mysterious disease is killing off U.S. honeybees, threatening to disrupt pollination of a range of crops and costing beekeepers hundreds of thousands of dollars, industry experts said on Monday. Beekeepers in 22 states have reported losses of up to 80 percent of their colonies in recent weeks, leaving many unable to rent the bees to farmers of crops such as almonds and, later in the year, apples and blueberries. "It's unusual in terms of the widespread distribution and severity," said Jerry Bromenshenk, a professor at the University of Montana at Missoula and chief executive of Bee Alert Technology, a company monitoring the problem. Dave Hackenberg, a Pennsylvania beekeeper who reported the so-called Colony Collapse Disorder to researchers at Pennsylvania State University in November, said he had lost about 2,000 hives, which can each contain around 50,000 bees during the summer months. He estimated that he will lose as much as $350,000 after accounting for lost income and the cost of replacing bees. Researchers from state and federal agriculture agencies have been frustrated in their search for a cause because affected hives are often empty except for the queen and a few bees. The number of bees in a hive typically diminishes over a period of days to the point where there are very few or none left, Hackenberg said. There is no indication of where the bees have gone or what drove them away, he said. "The rate of loss is startling," said Jeff Pettis, a bee researcher at the U.S. Department of Agriculture in Beltsville, Maryland. Pettis said the bees may have been killed off by a combination of factors including parasitic mites and a lack of nectar in pollen. Scientists are also looking into whether there is a link with significant recent bee losses in some European countries, particularly Spain. Bromenshenk of the University of Montana said the symptoms are similar to "Dwindling Disease" that affected the U.S. bee population during the 1960s. Some beekeepers have told him that they have been seeing the problem for up to two years but have not reported it to authorities. "It remains to be seen whether this is something new," he said.
