Despite widespread declines in honeybees over the past winter, supplies of hives for pollinating tree fruits in the Pacific Northwest were expected to be adequate.

Beekeepers from coast to coast have reported that bees mysteriously left their hives. The phenomenon is being called "colony collapse disorder," though some people involved in the bee industry think that a number of different factors might be at play.

Joe Traynor, a bee broker in Bakersfield, California, said losses were sporadic. "Some beekeepers definitely had bad losses, and other beekeepers are doing quite well," he said.

Dr. Eric Mussen, honeybee extension specialist at the University of California, Davis, said beekeepers always expect to lose some bees during the winter. At one time, they’d be content to lose up to 10 percent of their bees. After parasitic mites became a problem in the 1980s, losses of up to 20 percent seemed acceptable. But this year, beekeepers are reporting major losses—anywhere from 40 to 80 percent. One beekeeper in Washington State lost all but 8 of his 4,000 hives, Mussen said.

"It’s definitely out of the ordinary. We haven’t seen losses like those for some time."

Heavy bee losses have been reported in other areas of the country, from the East Coast to the Midwest, but not all bees have been affected, Mussen said.

Horrible time

"Interestingly, some people had a horrible time with it, and other beekeepers are sitting there thinking, ‘I don’t know what you’re talking about. There’s no problem with my bees.’"

A number of theories have been put forward to explain the disorder. Dr. Jerry Bromenshenk, biologist at the University of Montana, is investigating whether it is related to pesticide use on crops that bees come into contact with.

Dr. Diana Cox-Fisher at Pennsylvania State University and state apiarist Dennis vanEnglesdorp are researching whether some disease might be to blame for the severe losses reported in Pennsylvania. "We have lots of questions, and not that many definitive answers," Cox-Fisher said.

They have ruled out the idea that it is caused by certain toxins in the environment, although it is possible that exposure to some toxin might be making the bees more susceptible to disease, she said. She believes pathogens are part of the problem.

The disorder is not limited to migratory beekeepers and has affected hives that haven’t been moved around.

Winter bees

Mussen said summer bees live for about six weeks, then fly off into the field and die. Winter bees, however, usually survive from the fall, through the winter, and into February and March, when they’re needed to pollinate almonds. But this year, the winter bees were also going out and disappearing.

He thinks the losses might be related to poor pollen. If the winter bees that are doing the brood rearing are not getting enough nutrients, they use their own body resources to feed the young. Those young bees are the ones that are supposed to rear the next brood, and if they are malnourished, it creates a downward spiral, with the bees becoming progressively weaker and susceptible to diseases.

The main cause of poor pollen is drought, Mussen said, and in 2006, a huge portion of the United States suffered from drought conditions. He wonders if the pollen that the bees went out and collected had low nutritional value.

The bee losses became evident as beekeepers prepared to move their bees into California almond orchards in February.

Dan Cummings, a beekeeper and almond grower in Chico, California, said it takes about 1.4 million bee colonies—almost 70 percent of all the bees in the country—to pollinate California’s 600,000 acres of almonds.

Though the hives were weaker, there were enough to do the job, Traynor reported. "When all was said and done, the almond growers got their complement of bees. Some of the hives were not as good as they should have been, but the weather was good, and the crop shouldn’t suffer."

The colonies should have gained strength during almond pollination because almond pollen is very nutritious, and no problems were expected in supplying bees for the 250,000 acres of tree fruits in Washington.

Almost every beekeeper in the Pacific Northwest that puts bees in apples had them in almonds first, Traynor said. "Apple growers are really reaping a tremendous benefit off the almond bees."

Yakima, Washington, beekeeper Sue Olsen said losses over the past winter have been variable and depend to a large extent on beekeeping practices. She also expected adequate bees for apple pollination. "There will be enough bees, but I can’t say at what price," she said. "I think there will be plenty of people coming up here." Almond growers typically pay much more for bees—up to $140 per hive—compared with the $40 or less per hive that apple growers pay. Olsen said that’s because the economics of the crop are different. The price of almonds is sky-high, while apple growers are struggling to stay in business. Three years ago, when there was a shortage of bees in California, almond growers bid against each other to get the bees they needed. Almond acreage continues to increase.

Beekeeper Matthew Hutchins, of Dayton, Washington, said Washington orchardists have the almond industry to thank for the fact that they have adequate bees. Money he earns in California covers the cost of maintaining and transporting the bees, while the money he makes in Washington goes towards his living expenses. "If it wasn’t for the almonds in California, this whole bee industry would be dead right now," he said.

He brought his bees back from California in March, in time to pollinate apricots in Washington and had to settle for $38 per hive. He said he’s had difficulty keeping contracts because of competition from large bee suppliers who are undercutting the price. As smaller beekeepers go out of business, the remaining ones are getting larger. Hutchins has about 1,400 hives, which he considers about the right number for him to manage properly. He thinks the so-called colony collapse disorder is caused by a combination of factors, including pesticide poisoning, diseases, and mismanagement.

Some beekeepers are trying to keep their hives pumped up year round and staging them in California for the winter, he said. Hutchins thinks the bees have a natural cycle and need a rest period during the winter.