Farm Progress

Researchers seek clues for honeybee decline

David Bennett 1, Associate Editor

January 13, 2012

5 Min Read

In recent years, as honeybee populationshave dived alarmingly, research funding has been lined up and scientists have rushed to find the cause of the insects’ strange behavior, massive die-offs and colony abandonment.

Despite the hard work, the malady — colony collapse disorder — is not yet fully understood and U.S. crop yields, which rely on the bees as chief pollinators, remain vulnerable.

Farm Press spoke with Jerry Hayes, chief of apiary inspection at the Florida Department of Agriculture, about where research stands, how beekeepers are dealing with the problem, and the cocktail of chemicals bees are regularly exposed to. Among his comments:

The latest on honeybees…

“Unfortunately, not much has changed since we last spoke a couple of years ago. Our latest survey showed, once again, about a 30 percent loss of honeybee colonies.”

Researchers have “found some viruses in honeybees. Other data have additional information on pesticides, nutrition, parasites, and other things.

“We haven’t been able to come up with any particular Best Management Practices or recommendations beyond what beekeepers already know. There’s nothing yet available to hang your hat on.”

Is there any sense that the causes of the collapse are coalescing around something? Or is everything still fuzzy at the edges?

“It’s still fuzzy at the edges. We do have clarification and confirmation of what many of us thought going back to the known suspects. Varroa mites (http://en.wikipedia.org/wiki/Varroa_mites) are parasites. They pierce a cuticle and leave open wounds, vector pathogens and send the dominoes falling.

“In my mind, controlling varroa mites is probably 80 percent to 85 percent of our problem. But we haven’t been able to do that very well. How do we do it? After all, killing an unwanted bug that’s on a beneficial bug is tough. Certainly, you can formulate chemicals that will kill the little bug. And that’s been done, but it has led to chronic exposure to those chemicals by the desirable bug, the honeybee.

On nutritional issues…

“Commercial, migratory beekeepers take their bees everywhere and must feed them artificial diets. There are so many colonies there aren’t usually enough natural resources to care for them.

“And when they do put them on natural resources, it’s for fee-based pollination – 500 acres of watermelons or 1,000 acres of almonds. That prevents a diversity of diet; they aren’t getting a diversity of amino acids and vitamins and minerals.

“Then, there are the introduced pathogens. We’ve had a lot of smart people with expensive equipment looking at these. If you or I don’t feel well, we go to the doctor. He’ll say, ‘Well, you’ve got a virus. Go home, drink fluids, go to bed for a couple of days and you’ll be okay.’ How do you take care of virus in a honeybee? We have yet to figure that out.”

On environmental toxins…

“There are environmental toxins affecting honeybees. The bees placed in production agriculture locations — and other locations — are exposed to a lot of chemicals.

“Not to pick on agriculture, or ag-chemical companies, but a lot of chemicals are used to control ‘bad’ bugs. We appreciate that. We eat very well in this country because we control pests and produce good crops.

“But again, honeybees are a bug and they’re exposed to these chemicals at times. Maybe they aren’t exposed in acute doses, but rather in chronic, sub-lethal doses” that build up.

“In some of our experiments, we’ve looked at residues of chemicals in beeswax, bees, broods, and pollen. We’ve come up with about 170 chemicals in beeswax and bees. Again, not in acute doses, but sub-lethal.”

On synergism…

“What happens when you mix 170 different chemicals in a beehive? What synergism is going on? We do know there is some synergism between some fungicides and pesticides. When growers tank mix things, it can increase the toxicity of the pesticides, sometimes as much as 1,000 percent.

“The only thing I can tell you for sure: I’m surprised all honeybees aren’t already dead. From what I’ve learned over the last five or six years, it’s obvious they’re tough.

“Darwinism is in action in many of these hives. Weak honeybees are killed off quicker. And there is some evidence that some honeybees have resistance to some chemicals, some miticides.”

On how beekeepers are keeping ahead of the collapse disorder…

“If it wasn’t for honeybee biology — allowing a beekeeper to basically artificially create a swarm, split a colony into two or three — we wouldn’t be having this discussion. I’d be saying, ‘Can I super-size that for you, sir?’ As long as beekeepers can keep doing that, we have hope. They might not be able to get ahead of the game, but they can stay even.

“That leads to a couple of questions: How long can that be sustained? Is there a tipping point in that approach? In the end, do consumers care where their food comes from?”

On Hayes’ research…

“We’ve been fortunate to receive resources from the state of Florida, which understands how important beekeeping is. As an extension, that work benefits the eastern United States, because commercial beekeepers travel to Florida to do some of the management work we talked about — splits and dividing hives.

“So, we’re partnering strongly with Dr. Jamie Ellis at the University of Florida on RNAi (http://en.wikipedia.org/wiki/RNAi) technology. With a private company, Beeologics (http://www.beeologics.com), we’ve looked at control of the acute paralysis virus.

“Now, we’re looking at control of the varroa mite using RNAi technology to target certain genes and be able to back away from use of some of the miticides.

“RNAi is precursor to DNA. All creatures have DNA and in the process of protein synthesis in insects we can target some of that with RNA and disrupt it. That leaves the mites less robust.”

“We want food security in this country. We go to the grocery store — the produce section, in particular — and read the labels to see where our produce comes from. I’m always suspicious of processes, products and treatments that aren’t allowed in the United States.

“I want growers in the United States to grow more things. But that means we must have a healthy honeybee population in order to provide the wide array of fruits, vegetables and nuts everyone wants.”

About the Author(s)

David Bennett 1

Associate Editor, Delta Farm Press

David Bennett, associate editor for Delta Farm Press, is an Arkansan. He worked with a daily newspaper before joining Farm Press in 1994. Bennett writes about legislative and crop related issues in the Mid-South states.

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