Is hard living catching up with some of agriculture's most diligent workers?

Could be, according to Jerry Hayes, Assistant Chief at the Florida Department of Agriculture and Consumer Services' Bureau of Apiary Inspection. Beekeepers in Florida, Texas, Pennsylvania, California and other states are puzzled as to why adult bees have been dying in record numbers. Researchers like Hayes have dubbed the problem"fall dwindle disease."

Hayes co-authored a preliminary report published in December describing how seven commercial beekeepers have lost 30 to 90 percent of the adult bees in their hives. It speculated on possible causes, but came to no conclusions.

"IT'S A HEAD SCRATCHER."

Jerry Hayes, of the Florida Department of Agriculture's Bureau of Apiary Inspection, is one of those researching a recent a drastic decrease in the commercial honey bee population.

A couple of months after the report was issued, researchers say the answer is still elusive. "Basically, it's still a head scratcher," said Hayes. "There are a variety of suspicions, but really nothing to hang your hat on at this point."

The huge die-off problem surfaced late last summer when beekeepers across the country began notifying authorities that bees in seemingly healthy colonies were disappearing. Shortly afterward, Hayes and his Florida team, along with researchers at Pennsylvania State University, the University of Montana and the Pennsylvania Department of Agriculture, started making phone calls.

The researchers conducted extensive interviews with seven beekeepers in four states who had a few things in common. All were migratory beekeepers, meaning that they moved the colonies to different regions depending on where the need existed for pollination. All had a "dead out" rate of at least 30 percent, compared with the normal 10 percent. And they all added healthy bees to those colonies where bees had previously died in an effort to jump-start breeding.

Why is a bee die-off important? Honeybees are very important to the food supply. Besides producing honey, these bees are used to pollinate crops like citrus, blueberries, watermelons, cucumbers and squash. Without a supply of dependable honeybees in the field, many experts say crop production could decrease by a third.

It's not the first time in the past few years that honeybees have been under the gun. They've been attacked by a couple of dangerous types of mites. In addition, Africanized bees have been causing a scare and creating a PR problem for the good bees (European honeybees). To many people, anything that buzzes is a bee, and if one is scary, they all are.

What do the experts theorize? One thought has been repeated on blogs and in interviews with beekeepers and researchers alike. That is - bees live a tough life. "Look at beekeeping as a huge cooking pot," said a contributor to the blog forum Fall Dwindle Disease, what does it mean to you? (www.beesource.com). While not speaking for all beekeepers, the contributor wrote, "Inside that pot is a deadly brew of bad breeding, bad management, pesticides, chemicals, introduction of foreign pests and diseases, and about everything bad you can think of," he said, allowing that much of this is compounded not always by choice, but by necessity.

Varroa mites are a major threat to honeybee health. A varroa mite is shown on the back of this bee. Photo by Stephen Ausmus, USDA ARS images

"Bees are under tremendous stress," Hayes agrees. "I'm amazed that there are any honeybees alive. They're tough." Hayes points out that in addition to the threat of varroa mites and tracheal mites, that "everything commercial beekeepers must do to a beehive is, in fact, unnatural." Beehives, he says are not meant to be in those white boxes. They're not meant to be fed supplemental foods. They're not meant to be put on semi-trucks and driven 5,000 miles. "None of that is natural, so bees are tough. They keep doing what they do," Hayes said.

So could all that stress have a cumulative effect? Could all that adversity suddenly be coming to a head for certain colonies? That's what Hayes and other researchers are trying to determine. Perhaps there's a genetic component that makes some bees weaker and more susceptible to pests and disease. "We're trying to find out what the commonality is. Darwin could come into play and wipe out all the weak ones and leave the strong ones to repopulate," said Hayes.

Commonalities could come in many different packages: bacteria, weather patterns, buildup in honeycombs, even stress from the bees' migratory lifestyle.

Out of necessity, honeybees live in an unnatural environment that may contribute to stress and disease.

In the meantime, there is some progress in the research department. Whatever the cause is, it seems to be transferable, Hayes says. "Whether it's an organism, a virus, a fungus or something else, it can be transferred from colony to colony. In that vein, beekeepers are trying their best to maintain and replace the combs where bees live and work." One beekeeper, Hayes says, even had his equipment irradiated in order to re-use it with some degree of confidence.

Work continues to find a cause, prevention and cure. "We're interviewing beekeepers. We're looking at maps to see where those people have been, where they obtained the queens, what states they go to, what they've fed their bees, and what medications or chemicals they've used. Then we'll gather all this information to see if there's something that will let us say, "Aha. Right now, we may find two or three commonalities, but the fourth or fifth variables don't fit."

Hayes says samples have been sent to labs at the Universities of Florida and Montana as well as to Penn State, Kentucky State University and USDA. The investigation continues.

"We're sampling and dissecting and analyzing," Hayes said. "But nothing new is jumping out where we can say, 'Oh my goodness, it's a new disease.'"

The report, Fall Dwindle Disease: Investigations into the causes of sudden and alarming colony losses experienced by beekeepers in the fall of 2006, can be viewed at: www.ento.psu.edu/MAAREC/pressReleases/PrelimReportFallDwindle.pdf