Hive loss is enigma

For many beekeepers, the mystery is as deep as the devastation. A hive begins as a set of wooden frames whose combs hold thousands of worker bees, pollinators of all manner of crops. Then the insects scatter without warning, deserting the colony and leaving the queen bee and her young to starve — and farmers scrambling to keep up their fruit and nut orchards.

The syndrome, colony collapse disorder, has gutted numerous beekeeping operations since its discovery two years ago. At the start of a new growing season in the Mid-Valley, many farmers — especially almond growers — must cope with a tightening stock of healthy bees as researchers continue looking for the cause of dying hives.

"This is the problem which has befuddled us the most," Eric Mussen, an entomologist at the University of California, Davis, said Tuesday. "Since we can't put a finger on why or how this is how it is, it's difficult to tell anybody how to treat it."

Various pests have racked U.S. apiaries in the last quarter century, most notoriously Varroa mites that suck the blood from honeybees. But no malady has frustrated researchers and farmers quite like colony collapse disorder, first discovered in Pennsylvania hives in 2006.

Though most Mid-Valley beekeepers have not yet reported the mortality rates of 50 percent or more seen in other parts of the country, the worry is acute because the region is an almond-growing center. The nut trees rely solely on bees moving from flower to flower — the journey the insects make to gather nectar for the honey that sustains their hives in winter — to fertilize blossoms and produce the next crop.

Mite infestations, poor rainfall and a lack of bee forage have forced apiaries to spend more on nutritional supplements and pesticides to keep up the insects' health. Local almond farmers have reported seeing the cost of hive rentals triple in the past four years, to $150 or more per colony. Almond orchards typically are served with one to three hives per acre.

"The strength of the hives available for pollination is a great concern to us," said Elaine Rominger, owner of 2,000 acres of almonds in Arbuckle.

A clear cause for the vanishing bee colonies remains elusive. Research has focused on possible suspects such as a paralytic virus or a more virulent form of the Nosema fungus. But Mussen, the UC Davis researcher, conceded none has yet been implicated in a certain cause and effect — or why some hives are destroyed while neighboring ones stay intact.

A major bee supplier in Yuba City, Valeri Severson of Strachan Apiaries, said her company has managed to keep up the number of colonies at the total of about 9,800 typical in late winter, partly through more and earlier feedings of supplemental food. But the enigma of colony collapse disorder's origin leaves apiaries coping not only with killer microbes but the whims of rainfall and the of pesticides that keep the insects healthier.

"Disease is the most important thing now," Severson said. "The climate we can deal with a little easier, but disease and not having the right stuff to treat them with — we have had several diff chemicals to kill mites, but the mites have become resistant."